Arnaud Lamy

Sandrine Costa

Céline Vial
email: celine.vial@inrae.fr

Ikpidi Badji

Myriam Carrère

Pascaline Rollet

Marie Josephe Amiot

Horsemeat consumption in France: determinants and sustainable market perspectives

Keywords: Horse meat, meat acceptance, sustainability, consumer surveys, nutritional values

In France, the horsemeat market has been declining for about 50 years and has become a specialized market. Our study aims to understand this decline with regard to the drivers and practices of consumers and non-consumers of this meat, in order to estimate the potential for this market development. To study horsemeat consumption, we analyze two sets of data: two large-scale surveys carried out on the French general population, and one ad-hoc survey focusing more specifically on the representations of horses and horsemeat. Our results underline the potential for increasing horsemeat consumption from a sustainability perspective. The question of moral acceptance remains a determining factor in the consumption of this meat. Once this factor is taken into account, horsemeat appears relevant in the diversification of animal protein consumption because of its particular nutritional and environmental properties and similar culinary use to that of other red meats. Horsemeat can thus lay claim to becoming a sustainable alternative to beef consumption.

Introduction

Considering the issues involved in the production and consumption of meat, horsemeat has a particular status, combining several advantages but also disadvantages.

From a nutritional quality perspective, horsemeat contains more iron and zinc than other meats, and has a low fat content with a good lipid profile due to the equine digestive physiology that allows the transfer of n-3 polyunsaturated fatty acids (PUFAs) from pasture to meat [START_REF] Belaunzaran | Horsemeat for human consumption -Current research and future opportunities[END_REF][START_REF] Lorenzo | Horsemeat: Increasing Quality and Nutritional Value[END_REF]. Consequently, horsemeat consumption increases the status of PUFA content in the erythrocytes of consumers [START_REF] Del Bò | Horse meat consumption affects iron status, lipid profile and fatty acid composition of red blood cells in healthy volunteers[END_REF].

From an environmental point of view, horse breeding has ecological benefits linked to the inherent nature of equines as non-ruminant herbivores (equine grazing), and to their specific land use in areas where other livestock are currently absent. In terms of equine grazing specificities, the absence of rumination leads to lower methane emissions compared to cattle (117.9 kg CH4/dairy cow/year and 20.7 kg CH4/horse/year in France) [START_REF] Rzekęć | Green Assets of Equines in the European Context of the Ecological Transition of Agriculture[END_REF]. In addition, the breeding of heavy horses for meat in France allows the maintenance of nine threatened local heavy breeds and keeps areas open through grazing or agrotourism [START_REF] Bigot | Productions et activités équines en France : quelles contributions à la durabilité de l'agriculture ?[END_REF].

Moreover, the maintenance of horse slaughter (and consequently horsemeat consumption) enables the avoidance of food waste as well as the possibility of ending horses' lives in respectful conditions, instead of keeping them in poor conditions without any care [START_REF] Saastamoinen | Promoting slaughtering of horses and consumption of horsemeat -ethical horse keeping and meat production[END_REF].

We understand the term "sustainable market" to mean the set of production modes and commercial practices that fulfill the needs of current generations without compromising those of future generations, taking into account the environmental, economic, social and health impacts of these activities.

All these aspects imply that in sustainability terms, horsemeat could be a good substitute for beef. It would thus be desirable to increase its consumption [START_REF] Belaunzaran | Horsemeat for human consumption -Current research and future opportunities[END_REF]. Nevertheless, any increase in this consumption is conditional upon its acceptance [START_REF] Belaunzaran | Horsemeat for human consumption -Current research and future opportunities[END_REF]. For instance, [START_REF] Popoola | Free word association perceptions of red meats; beef is 'yummy', bison is 'lean game meat', horse is ' limits[END_REF] show that horsemeat is not associated with food among Canadian consumers and that its consumption would be unacceptable to them. By contrast, hippophagy was legally authorized in France in 1866 and is still practiced in the country (Lamy et al., 2020).

All meat consumption is strongly modulated by psychological determinants, personal convictions and beliefs. The concept of the "meat paradox" reflects the internal conflict within the meat eater, divided between the pleasure of eating animal flesh and the moral discomfort of killing the animal [START_REF] Loughnan | The role of meat consumption in the denial of moral status and mind to meat animals[END_REF][START_REF] Loughnan | The Psychology of Eating Animals[END_REF]. This cognitive conflict is stimulated by the phenomenon of anthropomorphism and the rise in empathy toward animals, which have a deterrent effect on meat consumption in general [START_REF] Niemyjska | Too humanlike to increase my appetite: Disposition to anthropomorphize animals relates to decreased meat consumption through empathic concern[END_REF][START_REF] Zickfeld | Too sweet to eat: Exploring the effects of cuteness on meat consumption[END_REF]. Eaters who are most uncomfortable then use strategies to reduce the dissonance between these contradictory cognitions (Séré de [START_REF] Séré De Lanauze | Dissonance cognitive et stratégies du consommateur face à une information critique : le cas de la consommation de viande[END_REF]. These strategies include the denial or downplaying of the emotional and moral capacities of livestock [START_REF] Bastian | Don't Mind Meat? The Denial of Mind to Animals Used for Human Consumption[END_REF][START_REF] Bratanova | The effect of categorization as food on the perceived moral standing of animals[END_REF] and, conversely, the attribution of such capacities to non-consumable animals. From this point of view, horses are then perceived as being mentally gifted, and their meat is perceived as non-consumable, according to a survey conducted in Australia, for example [START_REF] Bastian | Don't Mind Meat? The Denial of Mind to Animals Used for Human Consumption[END_REF].

As [START_REF] Belaunzaran | Horsemeat for human consumption -Current research and future opportunities[END_REF] point out, there are strong cultural differences between countries concerning the consumption of horsemeat and consequently strong differences in the quantities consumed. The present article focuses on the consumption of horsemeat in France. Indeed, France weighs significantly in the international horsemeat market, since it is one of the main importing and exporting countries [START_REF] Belaunzaran | Horsemeat for human consumption -Current research and future opportunities[END_REF]. It is also one of the countries where per capita availability is higher than the world average [START_REF] Belaunzaran | Horsemeat for human consumption -Current research and future opportunities[END_REF]. However, national horsemeat consumption was divided by 10 between 1980 and 2018, while over the same period, the population increased by 25%. Per capita consumption dropped from 1.67 kg/capita/year to 0.15 kg/capita/year, which suggest an irreversible trend in consumption.

Analyzing the determinants and practices of horsemeat consumers and non-consumers could provide additional information to help to understand the situation, as well as levers to increase horsemeat consumption with the aim of furthering the sustainable development of the equine sector within a sustainable market perspective. Thus, we examine horsemeat consumption in the French context. To this end, we propose a short literature review on the specific status and acceptance of horsemeat. Next, we analyze the individual characteristics of horsemeat consumers and non-consumers through two large-scale surveys (INCA2, Kantar WorldPanel). Finally, through an ad-hoc quantitative survey, we study the representations that consumers and non-consumers have of horses, as well as potential levers for and obstacles to increasing horsemeat consumption, in particular among current non-consumers.

Literature review: Horsemeat status, history and market

Specific features of horses linked to their status and utilizations

The horse is an animal with a particular status stemming from its various uses: domestic animal for leisure and sport, working animal for transportation, tourism or agriculture, and livestock for meat and milk.

From a historical point of view, the use of horses for working activities has long been dominant, while their use in leisure and sports activities is more recent and has become extensive. Finally, their use as food has always existed, although with notable spatio-temporal differences.

Regarding the cultural dimension, societies differ in terms of the (real and symbolic) status that they bestow upon horses. For example, [START_REF] Ferret | Hippophiles et Hippophages[END_REF] compares Yakutia (Russian republic in the Far East)

with France. This author shows that the Yakuts (semi-nomadic people) are horse people, and the animal is also the emblem of their nation. This animal is venerated and has a multi-purpose role, as it is used as a worker, for transportation, and for the production of milk, meat, fat, horsehair and fur. Ferret reports the more unidirectional purpose of horses in France, mainly oriented towards leisure activities.

Short overview of the history of horsemeat consumption in France

From the Middle Ages, French people rejected the consumption of horsemeat for symbolic, religious and health reasons, and this lasted for a long period of the country's history. Nevertheless, the availability of horsemeat following the slaughter of an old or injured animal gave rise to opportunistic consumption. Consequently, horsemeat consumption was negatively perceived: it was seen as unmentionable, taboo, only acceptable in times of crisis like famine or war. Gradually, the consumption of horsemeat took on an immoral, or even shameful character.

A change occurred in the 19th century. Some European countries bordering France, such as Germany and Belgium, took the decision to legalize the consumption of horsemeat [START_REF] Gade | Horsemeat as human food in France[END_REF]. Part of the medical, hygienist and naturalist scientific community at that time seized upon this issue and positioned themselves in favor of hippophagy. Two individuals actively promoted horsemeat consumption in France: Isidore Geoffroy Saint-Hilaire (1805-1861), administrator and professor at the Museum of Natural History in Paris, andEmile Decroix (1821-1901), chief veterinarian for the French army and president of the French association for the protection of animals [START_REF] Gade | Horsemeat as human food in France[END_REF][START_REF] Leteux | Is hippophagy a taboo in constant evolution? Menu[END_REF][START_REF] Otter | Hippophagy in the UK: a failed dietary revolution[END_REF][START_REF] Pierre | L'hippophagie au secours des classes laborieuses[END_REF]. After demonstrating that horsemeat was safe, healthy and nutritious, both sought to promote its consumption among populations that were deprived of regular protein intakes. Among the working classes, horsemeat could provide a nutritious and high-quality protein intake at a lower cost, as it was less expensive than other meats. They also encouraged the consumption of horsemeat for ethical reasons linked to the animal. In the 19 th century, considerations about animal suffering were still limited, and horse owners pushed their animals to work to their limits. In such conditions, slaughter seemed to be a better fate for these horses than death from exhaustion [START_REF] Roche | La culture équestre de l'Occident, XVIe-XIXe siècle: l'ombre du cheval[END_REF]. The promotional work was done through the organization of banquets, scientific presentations, and the distribution of free meat to people in need [START_REF] Leteux | Is hippophagy a taboo in constant evolution? Menu[END_REF]. This challenging approach succeeded in increasing the acceptance of hippophagy. The Administrative Police Court of Paris legally authorized the practice for human consumption in 1866 [START_REF] Digard | Hippophagie[END_REF][START_REF] Leteux | Is hippophagy a taboo in constant evolution? Menu[END_REF][START_REF] Lizet | Le Cheval Français en Morceaux. Statut de l'Animal[END_REF][START_REF] Pierre | L'hippophagie au secours des classes laborieuses[END_REF].

At the end of the 19th and the beginning of the 20th centuries, the medical community recommended the consumption of horsemeat for its flesh and blood, in order to prevent and fight against prevalent diseases such as tuberculosis [START_REF] Pierre | L'hippophagie au secours des classes laborieuses[END_REF]. The sector then became more professional with the arrival of a specific venue for trading in horsemeat: the horse butcher's shop. Unlike traditional butchers, they could sell only horsemeat to customers. The sector quickly got organized through a professional syndicate. Demand for horsemeat rose to the point that imports became necessary from 1904 [START_REF] Pierre | L'hippophagie au secours des classes laborieuses[END_REF]. The number of shops increased, especially in Paris and in the large and medium-sized towns of France. In 1913, there were more than 300 horse butcher shops in the city of Paris alone [START_REF] Roche | La culture équestre de l'Occident, XVIe-XIXe siècle: l'ombre du cheval[END_REF].

From the second half of the 20th century, the consumption of horsemeat gradually declined (Figure 1), due to the convergence of several factors.

First, the perception of its health benefits regressed, particularly following several health crises such as salmonellosis (1967) and trichinosis (between 1975 and 2000) [START_REF] Ancelle | A multifocal outbreak of trichinellosis linked to horse meat imported from North America to France in 1993[END_REF][START_REF] Pozio | Horse trichinellosis, an unresolved puzzle[END_REF][START_REF] Simoons | Eat not this flesh: food avoidances from prehistory to the present[END_REF][START_REF] Touratier | A challenge of veterinary public health in the European Union: human trichinellosis due to horse meat consumption[END_REF]. Nutritional trends in the scientific literature of the time also argued in favor of a more plant-based and less meat-based diet [START_REF] Darmon | Une alimentation bonne pour la santé est-elle compatible avec une alimentation bonne pour l'environnement[END_REF].

Second, on the economic and social levels, horsemeat reflected a low social status, contrasting with the strong symbolic status that remained associated with the animal [START_REF] Simoons | Eat not this flesh: food avoidances from prehistory to the present[END_REF]. The socioprofessional category of workers that consumed more horsemeat than the other social categories in

France declined sharply (Marchand, 2010). Third, even if horsemeat consumption is decreasing, imports continue to be necessary to meet national demand, because horse slaughter has been steadily declining, with a fall of 40% between 2010 and 2020 in France.

Fourth, the number of horse butcher's shops has decreased dramatically whereas half of the supply of horsemeat relies on them. The other half is distributed through supermarkets, direct sales and small local markets representing a very small part of the market [START_REF] Cazes-Valette | Les déterminants du rapport à la viande chez le mangeur français contemporain[END_REF].

Fifth, horsemeat is now among the most expensive meats per kilo, with the price exceeding that of veal in 2014 (Figure 2). Even though the data represented in Figure 2 are overall prices (including all types of meat), horsemeat has remained comparatively the most expensive over the last 7 year period. Finally, on the cultural level, horsemeat consumption has struggled to gain a foothold elsewhere than in already established areas (Centre -North of France). French cuisine shows little interest in the product, and horsemeat is rarely served in restaurants. Finally, the number of defenders of the practice had diminished, unlike its detractors, such as animal protection and welfare associations [START_REF] Lizet | Le Cheval Français en Morceaux. Statut de l'Animal[END_REF].

The rapprochement between animals and man brings us back to the question of the moral acceptability of meat consumption and the anthropological categories of edible animals according to their proximity to humans [START_REF] Leach | L'unité de l'homme et autres essais[END_REF][START_REF] Merdji | L'imaginaire du dégoût : une approche anthropologique de l'univers émotionnel de l'alimentation[END_REF]. The consumption of horsemeat is a particularly pertinent example. Over the course of the 20th century, horses gradually shifted from working activities to leisure activities, thus developing a more hedonic and sentimental relationship with humans [START_REF] Digard | Hippophagie[END_REF]. In their work on horsemeat consumption in the Finnish context, [START_REF] Leipämaa-Leskinen | A semiotic analysis on cultural meanings of eating horsemeat[END_REF] show that the meanings related to a living horse can be transferred to those of horsemeat, influencing cultural barriers that determine whether this meat is suitable or not for food consumption. Although horsemeat has followed the general structural downward trend in the same way as other meats, it clearly has its own specific characteristics. Compared to other types of animal production that are only dedicated to food consumption (such as cattle, sheep and pork), the moral acceptability of horsemeat consumption is socially disputed. The historical perspective testifies to the fragility of this acceptability.

Methodology

This paper relies on three complementary analyses. Two of them use pre-existing large-scale surveys, one on households' food purchases and the other on food consumption. These datasets have a certain number of limits. First, there is a risk that people may consume horsemeat outside of the survey and are considered as non-consumers whereas they are in fact consumers. Second, people may hide their horsemeat consumption as it can be considered socially unacceptable. These two biases could thus lead to an underestimation of horsemeat consumers. However, we consider these biases to be relatively weak. The third is an ad-hoc survey enabling us to study horse and horsemeat representations among consumers and non-consumers.

3.1.

Kantar survey

Kantar data

The data used come from the "Kantar WorldPanel" surveys of 2015 and 2017, enrolling respectively 5031 and 5131 French household panellists. They reported their purchases for at least 22 weeks and provided their socio-demographic and economic variables: age, sex, height, weight, education level, income, occupation status, presence or not of a child in the household, information on potential production of food at home in terms of the presence of a garden or fruit trees, and location of the family home (rural versus urban, North versus South of France).

The dataset provides detailed information on all purchases of food products, including products without a bar code and fresh products (meat, fish, fruits and vegetables). This database contains quantities and expenditures for several food products and therefore provides information on food consumption at home.

Note that this database does not provide information on food consumption outside the home, nor on self-made product consumption.

Probability estimation

Since the households included in the sample were observed over a variable number of consecutive weeks (at least 22 weeks), we first standardized the quantity of horsemeat purchased by each household. We computed the average yearly quantity of horsemeat purchased per consumption unit (according to the Organization for Economic Co-operation and Development (OECD) definition) for each household as:

𝑞𝑚𝑒𝑎𝑛 ∑ 𝑞 , 𝑤 * 𝑈𝐶
Where q i,k is the quantity of horsemeat purchased by household i during week k w i is the total number of consecutive weeks observed for household i (𝑤

22)

UC i is the size of household i expressed in consumption units (UC) according to the OECD definition (1 UC for the first adult in the household + 0.5 UC for other persons aged 14 or over + 0.3 UC for children under 14).

The overwhelming majority of households never purchased horsemeat within the time window selected for the study: 88.7% (respectively 90.5% in 2017) of households did not buy horsemeat over the 22 consecutive weeks surveyed. This implies that we have an over-representation of zero values in our horsemeat purchase data. This is why we cannot use the Ordinary Least Squares method [START_REF] Greene | Econometric Analysis[END_REF] to analyze the household's propensity to buy horsemeat: this method will not yield consistent estimates due to the over-representation of zero values. Importantly, it would lead to an underestimation of predictions of purchased quantities, and would bias the estimation of the coefficients associated with the explanatory variables. Several alternatives are commonly used to counteract such biases. One of the most widely used is the Tobit model, developed by Tobin in the 1950s [START_REF] Tobin | Estimation of Relationships for Limited Dependent Variables[END_REF]. However, this model assumes that the variables involved in the probability of purchasing horsemeat are also those that determine the quantity of meat purchased. Furthermore, the Tobit model assumes that the explanatory variables exert the same influence (i.e.: increase vs decrease) on the quantity of horse meat and on the probability of buying horse meat. However, it turns out that in our case, we cannot rule out the possibility that both decision-making processes are supported by different determinants. Therefore, we cannot hypothesize that they will have the same impact on each decision. Under these conditions, the Cragg model [START_REF] Cragg | Some Statistical Models for Limited Dependent Variables with Application to the Demand for Durable Goods[END_REF]) would be more appropriate than the Tobit model. Indeed, it removes the twofold constraint of the Tobit model. The Cragg model, also known as the double-hurdle model, proceeds in two stages. First, the probability of buying horsemeat is estimated with a Probit model (the selection model). Next, the impact of the individual determinants on the quantity of meat purchased is estimated with a truncated regression (the decision model: only quantities > 0 are taken into account).

Thus, the Cragg model consists of the following components:

The selection equation:

P 1 if P * 0 with P * αz u and u ~Ν 0, 1 (1)

otherwise

Where P* is a latent variable that takes the value 1 if the household buys horsemeat at least once in the year and 0 otherwise, z a vector of household characteristics and α a vector of parameters.

The decision model:

y y * if y * 0 and P * 0 with y * x β ε and ε ~Ν 0, σ (2)

otherwise

Where yi is the Napierian logarithm of the extrapolation of the yearly quantity of horsemeat purchased by consumption unit (according to the OECD definition), x is a vector of household characteristics and β is a vector of parameters.

𝑦𝑖 ln 𝑞𝑚𝑒𝑎𝑛 * 52 if 𝑞𝑚𝑒𝑎𝑛 0, 𝑦𝑖 0 if 𝑞𝑚𝑒𝑎𝑛 0
Finally, we also estimated the Tobit model, as the successive steps of the analysis led us to hold the same explanatory variables in both equations. Then we tested which model was the more appropriate.

We proceeded to a Chi-square test based on the likelihood ratio. The LR statistic is the following [START_REF] Greene | Econometric Analysis[END_REF]:

LR 2 lnL lnL lnL ~χ k
Where LT is the likelihood of the Tobit model, LP is the likelihood of the Probit model, LTR is the likelihood of the truncated regression model and k is the number of independent variables in the equations.

Finally, the Chi-square test elected the Cragg model (p-value = 0.000) for both samples (2015 and 2017) and confirmed our first assumption.

Kantar explanatory variables

The explanatory variables are: age of the panellist (person responsible for household purchases) (3 classes), education level of the panellist (4 levels), occupational status of the panellist (6 categories), income per consumption unit (in monthly euros), size of the municipality (3 categories, region (North versus South of France), availability of an orchard (in the main or secondary residence), availability of a vegetable garden (in the main or secondary residence), body mass index of the panellist (6 categories), and presence or not of a child in the household.

INCA2 survey

The

Quantitative exploratory analysis of horsemeat representations

This work relies on an ad-hoc quantitative survey. First, the aim is to explore consumers' and nonconsumers' representations of horses. Then the rationale for non-consumption of horsemeat (as reported by non-consumers) provides a glimpse of potential future consumption. The last sub-section focuses on how non-consumers perceive the mental capacities of horses [START_REF] Bastian | Don't Mind Meat? The Denial of Mind to Animals Used for Human Consumption[END_REF].

The quantitative survey was conducted in December 2018 through an online sampling company (Survey Sampling International). The sample includes 1005 people representative of the French adult population in terms of age, gender and socio-professional category.

Before starting the investigation, we asked participants to tell us what horses mean to them by spontaneously giving us 3 representative words (see Appendix 2). This question was asked before questioning people on their consumption of meat and horsemeat, such that participants' representations would not be influenced by the purpose of the survey. Finally, the last part of the study aims to measure participants' perceptions of the emotional and cognitive capabilities of horses. We use the 10-item scale of [START_REF] Bastian | Don't Mind Meat? The Denial of Mind to Animals Used for Human Consumption[END_REF]: "In your opinion, are horses capable of feeling hunger / fear / pleasure / pain / anger" and "In your opinion, are horses capable of self-control / moral sense / memory / empathy / planning". Answers were given on a 5-level Likert scale from "strongly disagree" to "strongly agree".

Results

Horsemeat purchases

According to the Kantar surveys, 11.25% of households bought horsemeat in 2015. This proportion decreased to 9.5% in 2017.

Among buyers, the average quantity was 1.36 kg/year/CU in 2015 and 1.20 kg/year/CU in 2017. These quantities differ according to the socio-demographic and economic characteristics of households. In 2015, the average quantities purchased by households whose panellists were in the 18-44 y-old category were 18% and 27.7% lower than the 45-64 y-old and >65 y-old categories, respectively.

Households with an education level below the baccalaureate bought 5% more than those with a higher education level (Bachelors' degree and above).

All these descriptive results were confirmed by econometric estimates to quantify the specific effects of each variable on the probability of buying horsemeat (Probit models) and on the quantity purchased (truncated models). Both models (2015 -table 1 and 2017 -table 2) highlight the fact that panellists under 44 years are less likely to purchase horsemeat and that they purchase lower quantities per year than others. Both models also show that the proportion of northern French households buying horsemeat is significantly higher than that among southerners. But there is no significant difference between northerners and southerners regarding the quantities bought by horsemeat consumers. In 2015, the results show that households owning a vegetable garden were more likely to consume horsemeat. Both models also provide evidence that households whose panellists are overweight are more inclined to buy horsemeat. But weight has no impact on the quantities purchased, except in 2015 for severe and morbid obese panellists who purchased more horsemeat.

In both the 2015 and 2017 models, the presence of one or more children in the household seems to increase the probability of consuming horsemeat. Moreover, the 2015 results also indicate that households with an income below the poverty level have a higher probability of buying horsemeat, but at the same time, that high-income horsemeat consumers buy higher quantities than the former. Both models (2015 and 2017) show that intermediate professions have a lower probability of buying horsemeat than the reference category of "employees/workers". The results are more ambiguous regarding "senior executives" and "students and unemployed people". On the one hand, the 2015 M3

model shows that a level of education above baccalaureate + 1 year (or more) is negatively associated with the probability of purchasing horsemeat, and on the other hand, the level of education below the baccalaureate is positively associated horsemeat consumption.

Horsemeat consumption

Table 3 summarizes the characteristics of individuals from the INCA2 survey. People are between 45 and 47 years old on average (no significant differences were found between Non-Consumers NC and Declared Consumers DC that include Factual Consumers FC). Men are significantly more represented in the sub-sample of horsemeat consumers (47% of DC sub-sample) than in the whole sample (41.3%).

Chi² tests highlight the differences among genders, socio-professional categories and regions of residence. Furthermore, the majority of NC of horsemeat are senior executives and higher intellectual professions, whereas consumers of horsemeat are employees (21%), pensioners (20%) and people without a professional activity (17%), or manual workers (15%). Last, horsemeat eaters are much more represented in the northern regions of France. respondents do not buy horsemeat because they do not like the taste or the color of this meat (4,9% of the whole sample).

An analysis of the representations of horses was first carried out for the whole sample. The responses are grouped into 12 different categories, which are detailed in Appendix 2.

Table 4

Number of citations of horse representations by category (quantitative exploratory survey, 2018).

The "meat" category is poorly represented, with only 32 occurrences (see Table 4). Representations related to the concrete physical features of the animal (67 occurrences) are in the minority compared to the qualifiers and attributes of horses (physical qualification: 632 occurrences), with a lexical field that is more complete and abstract. The vast majority of these terms have a positive connotation, highlighting the beauty, nobility or grace of horses. These qualifiers contribute to a form of idealization of the animal, testifying to an imagery that is still present in the lineage of the aristocratic status of the horse [START_REF] Leteux | Is hippophagy a taboo in constant evolution? Menu[END_REF]. Among the categories of occurrences, a macro-category (887 occurrences) can be created by grouping together three categories linked by the interaction between man and animal (racing with 381 occurrences, leisure with 290 occurrences, relationship with 216 occurrences). Finally, the results obtained underline the ambivalent status of the horse, which oscillates in a continuum with man at one pole and the animal at the opposite pole. The "animality" category (269 terms) brings the horse closer to the animal pole, while the anthropomorphic category of "abilities and characters" (235 terms) brings the horse closer to the human pole. Thus, the status and position of the horse within the human-animal relationship remains undecided.

Category

Representations do not differ between horsemeat consumers and non-consumers. However, among non-consumers, the representations are significantly different between those who express affective and moral reasons and those who have other reasons for not eating horsemeat (Khi2=62,7; p=2,8.10 -9 ), see table 5. The next part focuses on current non-consumers who do not invoke affective and moral arguments for not consuming horsemeat. Actually, the greatest potential for an increase in the consumption of horsemeat relies on this category. In terms of representations, these survey participants cite emphatic physical descriptions less often and horseraces more often, showing more utilitarian representations of horses than affective and moral non-consumers do. They also talk less often about horses' abilities and characters and more often about "animal" attributes, which reflects a status closer to the animal for these individuals (compared to affective and moral non-consumers). Now turning to the perception of the emotional and cognitive abilities of horses, these people credit horses with significantly fewer emotional and cognitive abilities than those who maintain affective and moral reasons for non-consumption (table 6). We may then assume that the consumption of horsemeat might be morally acceptable [START_REF] Bastian | Don't Mind Meat? The Denial of Mind to Animals Used for Human Consumption[END_REF] for these people. Their reasons for non-consumption are mainly related to supply, whereby it would be possible to increase their consumption if the supply changed, including changes in the places where products are sold, their prices and the visibility of products on the shelves. Some of them, however, do not want to eat horsemeat because of its taste or its color (some participants say they don't like red meat). To convince these consumers to consume horsemeat, it would be necessary to further develop communications on the nutritional benefits of horsemeat and to propose recipes that hide the taste and color, due to their preferences.

Discussion

From a sustainability perspective, horsemeat could be a good substitute for beef because of its environmental and nutritional benefits, provided that its consumption tallies with consumer preferences.

Our results show that the development of the horsemeat market is not only possible, but also that it can easily be steered in a sustainable direction.

Possible horsemeat market increase

Two groups of consumers have been identified as being likely to increase their consumption of horsemeat. On the one hand, households and individuals who already consume small quantities of horsemeat, and on the other hand, non-consumers of horsemeat who do not consume it for supply reasons. The potential for increasing horsemeat consumption through its current consumers is substantial. Indeed, Study 1 shows that horsemeat-buying households buy horsemeat only infrequently (on average they buy horsemeat one week in ten), and, according to the results of Study 2, only onesixth of reported consumers of horsemeat consumed it during the week of the survey.

Furthermore, according to the results of Study 3, a significant proportion (30%) of respondents who do not consume horsemeat would be likely to consume it. These consumers do not eat horsemeat because they do not think about it, or cannot find it. The potential for growth in the horsemeat market therefore appears to be considerable, once this rate of "potential consumers" is extrapolated to the proportion of non-consumers observed in Study 2.

5.2.

How can such an increase in the consumption of horsemeat respond to sustainability issues?

As highlighted in the introduction, horsemeat is nutritionally and environmentally attractive as a substitute for large ruminant meat. Moreover, it is a red meat with a taste which is quite similar to beef and is usually identified as a substitute for beef by French consumers (Lamy et al, 2020). In France, adult bovines (mainly beef) represent around a quarter of total meat consumption in France. The substitution of part of beef consumption by horsemeat would thus meet the sustainability challenges facing French food systems. Moreover, due to its nutritional qualities, eating horsemeat instead of beef could lead to a reduction in the total quantity of meat consumed, as consumers do not need to eat as much horsemeat as beef to get the same amount of iron, for example. Furthermore, horsemeat eaters have a lower socio-economic status (study1 and study 2), which is commonly associated with overweight [START_REF] Vernay | Association of socioeconomic status with overall overweight and central obesity in men and women: the French Nutrition and Health Survey[END_REF]. From a nutritional point of view, our results show that current consumers of horsemeat are heavy consumers of beef (study 2) and are rather overweight (study 1). Substituting some of the beef consumed by horsemeat among these populations is therefore particularly beneficial from a nutritional point of view, thanks to its low fat content and high fat quality. This nutritional perspective, added to the fact that horsemeat is more environmentally friendly than beef, means that a substitution of beef by horsemeat would lead to a reduction in the environmental impact of food systems, and an improvement in the nutritional quality of the diet.

The sustainability of food systems requires, among other things, food and nutrition security. One of the conditions for food security is that food should respect individual preferences. Thus, imposing the consumption of horsemeat on consumers or populations for whom it is not acceptable for affective, moral or taste preference reasons (aversion to red meat) would ultimately be contrary to the spirit of sustainability. Our results (study 3) show that a significant proportion of current non-consumers do not consume and do not buy horsemeat for affective and moral reasons. The market development plan for horsemeat must therefore respect these preferences and target other consumers. Thus, the targets identified in this research are either already consumers of horsemeat or non-consumers for whom the consumption of horsemeat is acceptable. Based on the results of Study 1 and Study 3, we estimate that these consumers would represent about 30-40% of the population.

5.3.

What policies and strategies are needed to make this increase in consumption possible and sustainable?

A critical element of the effects of horsemeat consumption on sustainability is the meat it replaces. For horsemeat to substitute beef as much as possible, communication actions should emphasize the benefits associated with this substitution.

But, the strategy to be adopted should differ according to the target.

Current non-consumers who would be prepared to eat it do not do so at present because they do not think about it and because they cannot find it (study 3). This underlines the need for a policy to promote this meat, and a distribution strategy to make it more visible, which includes increasing supply. The promotion of the consumption of horsemeat could be achieved on the one hand by a communication policy targeting the nutritional and environmental qualities of this meat, associated with a larger distribution making it possible to find horsemeat in all meat outlets. Moreover, it would be useful to develop and promote recipes and prepared dishes. On the other hand, an increase in the supply of horsemeat in the catering sector (commercial or collective) could encourage those who have never eaten it to try it.

Most current horsemeat eaters have a low socio-economic status and live in the north of France. Such characteristics suggest a cultural heritage of food traditions inherited from the emergence of hippophagy in France [START_REF] Digard | Hippophagie[END_REF]Leteux, 2005;[START_REF] Roche | La culture équestre de l'Occident, XVIe-XIXe siècle: l'ombre du cheval[END_REF]. Horsemeat preferences could also be due to a collective imagery that associates this meat with strength and virility. Promoting the image of strength and virility of horsemeat would reinforce its attractiveness among the working class and low socioeconomic status groups, which is one target. Nevertheless, its relatively high price may be an obstacle to increased consumption among these people. It is possible to find a high diversity of meats between beef, veal and lamb, with a high price variance depending on the cut of meat, whereas the choice between horsemeat cuts marketed at present is narrow, with only the most noble ones, so the most expensive, on offer. A diversification of cuts of horsemeat marketed would thus lead to a wider range of prices for this meat, and a more diversified use. An increase in consumption among people with a low socio-economic status would then be easier. For current consumers with a higher economic status, pricing will not be decisive whereas environmental and nutritional arguments could be.

Conclusion

In conclusion, the three studies performed in this research show that it is possible to increase the consumption of horsemeat in France. Given the targets identified, this increase could be achieved by substituting beef, thus leading to environmental and nutritional benefits. The principle of respect for individual preferences, which is necessary for a sustainable diet, would entail the targeting of consumers who are willing to consume horsemeat. This research thus identifies two targets (current consumers and non-consumers willing to consume it), and discusses the policies to be put in place to make this increase in consumption effective and sustainable.

Figure 1 :

 1 Figure 1: Evolution of horsemeat consumption in France since 1970 (IFCE)

Figure 2 :

 2 Figure 2: Evolution of retail meat prices since 2001 (IFCE)

  data come from the cross-sectional survey INCA2 carried out by ANSES (French Agency for Food,

	Environmental	and	Occupational	Health	&	Safety)	in	2006	and	2007

(https://www.anses.fr/fr/system/files/PASER-Sy-INCA2EN.pdf).

Only adult meat consumers were considered in our study, resulting in a sample of 1006 men and 1430 women, among whom 1595 adults declared never consuming horsemeat (hereafter, "non-consumers (NC)"), 841 were raw or cooked horsemeat consumers (hereafter, "declared consumers (DC)"), among them 60 reported having consumed horsemeat during the surveyed week (hereafter, "factual consumers (FC)"). Our INCA2 sample is divided into three sub-samples such that 65.5% are NC, 34.5% are DC among them 2.5% are FC (due to the very short period -one week -of dietary reporting). To compare the profiles of individuals between samples, we run non-parametric tests such as Wilcoxon's test and Chi² tests.

Table 1

 1 Impact of sociodemographic and economic variables on purchases of horsemeat in 2015 (estimated

	coefficients with the Cragg model)
		M1		M2		M3
	Variables	Truncated Probit	Truncated Probit	Truncated Probit
	Age
	18-44*	-0.22 +	-0.37** -0.20	-0.35** -0.20	-0.29**
		(0.125)	(0.060) (0.125)	(0.060) (0.133)	(0.063)
	45-64 (Ref : reference)	Ref	Ref	Ref	Ref	Ref	Ref
	65+	0.38**	0.08	0.40**	0.07	0.35**	0.05
		(0.121)	(0.065) (0.122)	(0.065) (0.124)	(0.065)
	Country size
	Rural areas		-0.04		-0.04		-0.05
			(0.063)		(0.063)		(0.063)
	Urban areas of 2000 to 199,999		Ref		Ref		Ref
	inhabitants
	Urban areas of 200,000 inhabitants		0.10 +		0.10 +		0.12*
	and more + Paris
			(0.058)		(0.058)		(0.058)
	Region of residence
	North	0.18	0.20**	0.19 +	0.19**	0.19 +	0.18**
		(0.112)	(0.052) (0.112)	(0.052) (0.112)	(0.052)
	South	Ref	Ref	Ref	Ref	Ref	Ref
	Orchard owner
	Yes		0.01		0.01		0.02
			(0.058)		(0.057)		(0.058)
	No		Ref		Ref		Ref
	Vegetable garden
	Yes		0.11 +		0.11 +		0.10 +
			(0.058)		(0.058)		(0.058)
	No		Ref		Ref		Ref
	Monthly income €/CU
	Poverty line	0.14	0.15 +
		(0.159)	(0.078)
	Poverty line to median income	0.08	0.08
		(0.135)	(0.065)
	Median income to 7th decile	Ref	Ref
	>7th decile	0.35*	-0.05
		(0.152)	(0.071)
	Body Mass Index
	Thinness	-0.17	-0.11	-0.08	-0.11	-0.16	-0.11
		(0.350)	(0.151) (0.351)	(0.152) (0.353)	(0.152)
	Normal weight	Ref	Ref	Ref	Ref	Ref	Ref
	Overweight	-0.07	0.17**	-0.08	0.17**	-0.08	0.16**
		(0.117)	(0.055) (0.116)	(0.055) (0.117)	(0.056)
	Moderate obesity	0.20	0.28**	0.16	0.29**	0.17	0.27**
		(0.154)	(0.077) (0.154)	(0.077) (0.155)	(0.077)
	Severe and morbid obesity	0.39 +	0.31**	0.35 +	0.32**	0.36 +	0.30**
		(0.210)	(0.108) (0.209)	(0.108) (0.210)	(0.108)
	No answer	-0.54	0.28	-0.55	0.27	-0.53	0.28

Table 2

 2 Impact of sociodemographic and economic variables on purchases of horsemeat in 2017 (estimated coefficients with the Cragg model).

		M1		M2		M3
	Variables	Truncated Probit	Truncated Probit	Truncated Probit
	Age
	18-44*	-0.35**	-0.29** -0.36**	-0.26** -0.34*	-0.24**
		(0.128)	(0.063) (0.132)	(0.063) (0.135)	(0.065)
	45-64	Ref	Ref	Ref	Ref	Ref	Ref
	65+	0.20	0.13 +	0.19	0.11 +	0.19	0.10
		(0.124)	(0.066) (0.127)	(0.067) (0.125)	(0.067)
	Country size
	Rural		0.03		0.01		0.01
			(0.064)		(0.064)		(0.064)
	UB 2,000 to 199,999 inhabitants		Ref		Ref		Ref
	UB of 200,000 inhabitants and Paris		0.14*		0.15*		0.15*
			(0.060)		(0.061)		(0.061)
	Region of residence
	North	0.10	0.15**	0.11	0.15**	0.11	0.14**
		(0.114)	(0.054) (0.115)	(0.054) (0.114)	(0.054)
	South	Ref	Ref	Ref	Ref	Ref	Ref
	Orchard owner
	Yes		0.02		0.03		0.02
			(0.058)		(0.058)		(0.058)
	No		Ref		Ref		Ref
	Vegetable garden
	Yes		0.03		0.02		0.03
			(0.059)		(0.059)		(0.059)
	No		Ref		Ref		Ref
	Monthly income €/CU
	Poverty line	-0.13	0.10
		(0.181)	(0.089)
	Poverty line to median income	-0.17	-0.06
		(0.155)	(0.074)
	Median income to 7th decile	Ref	Ref
	>7th decile	-0.05	-0.06
		(0.170)	(0.082)
	Body Mass Index
	Thinness	-0.38	0.10	-0.38	0.10	-0.38	0.10
		(0.304)	(0.143) (0.304)	(0.143) (0.304)	(0.143)
	Normal weight	Ref	Ref	Ref	Ref	Ref	Ref
	Overweight	0.08	0.14*	0.09	0.13*	0.08	0.13*
		(0.122)	(0.058) (0.122)	(0.058) (0.122)	(0.058)
	Moderate obesity	0.26	0.17*	0.26	0.16*	0.22	0.16*
		(0.162)	(0.078) (0.161)	(0.078) (0.161)	(0.078)
	Severe and morbid obesity	0.16	0.38**	0.17	0.38**	0.14	0.38**
		(0.201)	(0.106) (0.202)	(0.106) (0.201)	(0.105)
	No answer	0.51	-0.34	0.49	-0.37	0.47	-0.37
		(0.661)	(0.264) (0.662)	(0.267) (0.663)	(0.268)

Table 3

 3 Individual characteristics from INCA2 survey(2006)(2007).

				Whole	Non-	Declared	Factual
	Characteristics			sample (n = 2436)	consumer (n=1595)	consumer (n= 841)	consumer (n= 60)
	Age			45,44 ( +/-15,28)	45,69 ( +/-15,31)	44,98 ( +/-15,24)	47,5 ( +/-15,50)
	Gender	1: Men 2: Women		1006 (41.3%) 1430 (58.7%)	38,31 % 61,69 %	46,97 % (*) 40 % 53,03 % (*) 60 %
		1: Farmers		33 (1,36%)	1,63 %	0,83 %	3,33 %
		2: Craftsmen, traders, business leaders	67 (2,75%)	2,26 %	3,69 %	3,33 %
		3: Executives, higher intellectual professions	227 (9,32%)	10,28 %	7,5 % (*)	5 %
	Socio-Professional	4: Professions Intermediate	410 (16,84%)	17,74 %	15,12 %	13,33 %
	Category (SPC)	5: Employees	549 (22,55%)	23,45 %	20,83 %	16,67 %
		6: Manual workers	289 (11,87%)	10,47 %	14,52 % (*) 15 %
		7: Retired		490 (20,12%)	19,94 %	20,48 %	23,33 %
		8: activity No	professional	370 (15,20%)	14,23 %	17,02 %	20 %
		0: North West	369 (15,15%)	12,16 %	20,81 % (*) 26,67 % (*)
		1: East		260 (10,67%)	10,85 %	10,34 %	6,67 %
		2: Ile de France	328 (13,46%)	13,04 %	14,27 %	23,33 % (*)
	Zone	3: West 4: Centre		375 (15,39%) 265 (10,88%)	17,18 % 11,16 %	12,01 % (*) 6,67 % (*) 10,34 % 5 %
		5: Central East	297 (12,19%)	12,48 %	11,65 %	8,33 %
		6: South West	238 (9,77%)	10,72 %	7,97 % (*)	8,33 %
		7: South East	304 (12,48%)	12,41 %	12,6 %	15 %

Table 5

 5 Number of citations of horse representations by category, depending on the reasons for not eating horsemeat (quantitative exploratory survey, 2018).

		Number		%
	Category	Love and moral Other reasons	Affective moral reasons and	Other reasons
	Animality	90	62	9	11
	Other	72	69	7	12
	Ability, personality	82	40	9	7
	Racing	106	98	11	17
	Physical features	15	19	2	3
	Elite	17	7	2	1
	Leisure	101	66	10	11
	Nature	34	22	4	4
	Emphatic physical description	247	99	26	17
	Relationship	77	21	8	4
	Nothing	29	41	3	7
	Senses	93	43	10	7
	Meat	1	3	0	1
	Total	964	590	100	100

Table 6 .

 6 Attribution of emotional and intellectual capacities to horses by horsemeat non-consumers (for affective and moral reasons, or other reasons) and consumers (quantitative exploratory survey, 2018).

		Horsemeat non-consumers Affective Other and moral (1) (2) reasons reasons	Horsemeat consumers (3)	Comparison (1) to (2) tvalue (p)	Comparison (2) to (3) tvalue (p)
	Emotions	4.62 (0.72)	4.41 (0.82)	4.51 (0.76)	-3.03 (p=0.0026) -1.42 (p=0,15)
	Intellectual capacity	3.55 (1.06)	3.13 (1.10)	3.19 (1.01)	-4.41 (p<.0001)	-0.67(p=0.5)

Acknowledgements:

This work was supported by the Scientific Council of the French Institute for Horse and Riding.

Characterization of horsemeat consumption among adults

FC report consuming horsemeat mainly during meals taken at home (87.5%), with the family (66.7%), generally at lunch (79%) rather than dinner (21%), with an average of 133g per meal.

What about the consumption of other meats?

The INCA2 survey reveals that DC and FC of horsemeat eat more meat of all types than those who reported never eating horsemeat. The proportion of consumers of beef, pork, veal and lamb is higher among consumers of horsemeat (91.1%) than among non-consumers (70%), and consumers also consume more rabbit meat (no significant difference with pork and lamb). DC of horsemeat had a higher consumption of beef than those who did not consume horsemeat during the survey week. Moreover, FC of horsemeat consumed less beef (43.3% did not eat it during the survey week) than DC.

Horsemeat representations

Concerning the perception of cognitive and emotional capacities, an exploratory factor analysis led to a two-axis structure: the first one deals with emotions, the second one with intellectual capacities. Both have good statistical properties (see Appendix 3). Factor 1 includes 5 items (hunger, fear, pleasure, pain, anger), and factor 2 includes 3 items (self-control, moral sense, planning). This analysis led to the description of two variables: An "emotions" variable corresponding to the average of the 5 items in the "emotions" factor, and a "capacities" variable corresponding to the average of the 3 items in the "capacities" factor.

Statements on meat and horsemeat consumption (see Appendix 1) show that currently 91% of the sample are meat eaters, and 37% have already consumed horsemeat several times. Women and people aged 18-34 years are statistically less likely to consume horsemeat (respectively Khi2=24,3, p<0,0001 and Khi2=41,6, p<0,0001). Fifty-four percent of the whole sample have never eaten horsemeat but report eating other meats. However, among them, 331 respondents state that they cannot imagine eating horsemeat, either because they love the animal too much or for other moral reasons (33 % of the whole sample). For those who do not currently consume horsemeat, the respondents indicated that possible consumption of this kind of meat could be envisaged in the future. Thus 162 persons (16% of the whole sample) do not eat horsemeat because it is too expensive, it is too hard to find, it is not Frenchproduced meat or they do not instinctively think about buying this kind of meat (16% of the whole sample). All these reasons might be related to production, marketing and retailing strategies. 49 other


Mathieu Lavandier
email: lavandiermn@cardiff.ac.uk

Philippe Herzog
email: herzog@lma.cnrs-mrs.fr

Sabine Meunier
email: meunier@lma.cnrs-mrs.fr

Évariste Sanchez-Palencia

Physical and perceptual estimation of differences between loudspeakers

Keywords: Acoustics, Loudspeaker, Measurement Acoustique, Enceinte, Mesure

Differentiating the restitution of timbre by several loudspeakers may result from standard measurements, or from listening tests. This work proposes a protocol keeping a close relationship between the objective and perceptual evaluations: the stimuli are musical excerpts, and the measuring environment is a standard listening room. The protocol involves recordings made at a listener position, and objective dissimilarities are computed using an auditory model simulating masking effects. The resulting data correlate very well with listening tests using the same recordings, and show similar dependencies on the major parameters identified from the dissimilarity matrices.

Version française abrégée

L'objectif principal de ce travail est de proposer une méthode d'évaluation objective de la différence de reproduction du timbre par des enceintes acoustiques, telle qu'elle donne des résultats aussi proches que possible de ceux de tests d'écoute. Il s'agit uniquement d'évaluer des différences, et non d'estimer la qualité intrinsèque des enceintes. Pour que les évaluations objectives et perceptives soient aussi proches que possible, elles utilisent exactement les mêmes signaux de mesure.

Nous avons ainsi choisi d'enregistrer des signaux musicaux, reproduits par les différentes enceintes placées à la même position dans une salle d'écoute. La prise de son fait appel à une paire de microphones en configuration stéréophonique « AB ORTF », située à la place de l'auditeur. Les différences entre ces enregistrements sont alors évaluées au casque, par paires. Les mêmes enregistrements sont soumis à des méthodes d'analyse objectives, pour lesquelles ont été défini des « métriques » qui permettent de remplir des matrices de dissemblances similaires à celles issues des tests d'écoute. Ce protocole favorise ainsi le lien entre les deux évaluations, au détriment des caractéristiques spatiales de la reproduction du fait de l'écoute au casque, ce qui nous restreint à l'étude de la reproduction du timbre.

Des mesures ont été conduites à partir d'un échantillon de douze enceintes, qui reproduisaient trois extraits musicaux variés, et dont les dissemblances ont été évaluées par vingt-sept auditeurs non entraînés. Les résultats des tests d'écoute de l'ensemble des auditeurs ont permis d'établir une matrice de dissemblance moyenne, à laquelle ont été corrélées les neuf matrices de dissemblances objectives issues des métriques que nous avons proposées. Cette matrice perceptive moyenne a également fait l'objet d'une analyse statistique multidimensionnelle, qui a révélé que les différences perçues peuvent être représentées selon deux dimensions. La même démarche a été appliquée à chaque matrice de dissemblances objectives, et les espaces résultants ont alors été comparés visuellement à l'espace perceptif.

Parmi les différentes techniques d'analyse mises en jeu pour définir nos métriques, celles qui conservent toutes les informations du signal ont conduit à une corrélation relativement faible avec les résultats perceptifs. L'utilisation de densités spectrales de puissance, qui éliminent l'information de phase, a sensiblement amélioré cette corrélation. Elle est cependant encore nettement meilleure en utilisant des modèles auditifs qui prennent en compte le masquage fréquentiel et temporel (voir Fig. 1).

Cette hiérarchie est conservée en considérant, à la place d'une corrélation, la comparaison entre les espaces multidimensionnels issus de l'analyse des matrices de dissemblances : seules les métriques utilisant des modèles perceptifs semblent donner des espaces objectifs proches des espaces perceptifs (Fig. 2).

Introduction

Physical measurements used nowadays to differentiate loudspeakers do not take into account the mechanisms of perception. Conversely, the perceived characteristics of loudspeakers are evaluated rigorously through standard listening tests [START_REF]Sound system equipment -Part 13: Listening tests on loudspeakers[END_REF]. The aim of the present work is to propose a method for measuring loudspeakers that combines physical and perceptual points of view, so that the two approaches can be linked.

To achieve our goal, physical as well as psychoacoustical measurements were done in parallel, on a large panel of loudspeakers. We focused on the differences between loudspeakers, instead of a direct evaluation of their quality. Our main objective was to find a physical method of analysis that allows the loudspeakers to be differentiated from objective measurements in the same way as they are differentiated perceptually. To avoid many cultural biases, we did not try to evaluate the perceived quality of the loudspeakers. Such a quality evaluation might be a further work, if a reliable and non biased link between perception and physics could be established, eventually leading to methods for predicting the specific qualities of individual loudspeakers.

In this preliminary approach of estimating only the dissimilarities between loudspeakers, we have kept the objective and perceptual measurement protocols as close as possible, so that they could share almost the same data. This builds several constraints, which prevent the evaluation of spatial components of the reproduction: as most of these have probably been filtered out by our proposed protocols, we focus on the reproduction of timbre.

Experimental protocol

The protocol consists in recording separately the acoustical field radiated by each loudspeaker, ensuring that all loudspeakers are at the same position in the same room, with the microphones located at a fixed listening position, as specified by tests standards [START_REF]Sound system equipment -Part 13: Listening tests on loudspeakers[END_REF]. For estimating perceptive dissimilarities, these recordings are played to listeners via headphones in a soundproof room. In parallel, objective dissimilarities are estimated by analysing the same recordings using different signal processing techniques. This protocol keeps both estimations close together, but it induces distortions into the sound transmitted to the listeners' ears. As we are looking for differences between loudspeakers, we assume that these distortions do not influence our dissimilarity results because they are almost identical for all loudspeakers. However, this protocol prevents a rigorous study of the spatial components of the sound reproduction, because of headphone listening. Spatial aspects may indeed influence such a listening, but they cannot be studied in this way.

The stimuli were three musical excerpts, selected to cover a wide range of spectra and dynamics: Kan'nida ('Konsyans', percussions, 1.7 s), Mc Coy Tyner ('Miss Bea', jazz, 3.3 s) and Vivaldi ('L'Europa Galante', symphonic orchestra, 4.7 s). Twelve loudspeakers were involved, each one facing the microphones, in a monophonic reproduction situation. The influence of stereophonic reproduction has been studied, and does not significantly change the dissimilarity results [START_REF] Lavandier | The influence of stereophony on the restitution of timbre by loudspeakers[END_REF]. The field radiated by the loudspeakers has been recorded using a stereophonic AB ORTF technique. Two other recording techniques have also been tested: stereophonic MS and monophonic. As they do not lead to different conclusions, they are not presented here, but the corresponding results can be found in [START_REF] Lavandier | The restitution of timbre by loudspeakers in a listening room: perceptual and physical measurements[END_REF].

Perceptual and objective dissimilarities

Perceptual dissimilarities have been estimated from listening tests involving twenty-seven listeners, without training. Three tests were run, one for each musical excerpt. The loudness of the recordings has been equalized to avoid that listeners make their judgments on level differences, and pay less attention to other aspects. This loudness was set to a level of roughly 70 phons, as judged by the experimenters during informal listening sessions, and none of the listeners reported any level difference during the experiment. Paired comparisons were then used to evaluate dissimilarities between the different loudspeakers, using stereophonic headphones for reproducing the sound field recorded in the room for each single loudspeaker.

Pairs of recordings were thus presented in random order to the listeners. They were requested to quantify the dissimilarity within each pair by moving a cursor on a line displayed on a screen. The two end points of the line were labelled 'very similar' and 'very dissimilar'. The final dissimilarity matrix, from which the statistical analysis was done, was obtained by averaging the individual perceptual dissimilarities.

Our aim requires also to build dissimilarity matrices from the objective analyses, so that the objective and perceptual approach can be compared. To fill such matrices, we defined 'metrics' giving a single value from the differences between objective analyses of the recordings of the different loudspeakers. These objective analyses use exactly the same recordings as the listening tests. The right and left channels of the recordings have been analysed separately, but the figures below show the mean of both channels.

Nine metrics have been proposed (see [START_REF] Lavandier | The restitution of timbre by loudspeakers in a listening room: perceptual and physical measurements[END_REF] for details). They are differentiated by the letters (a) to (i) thereafter. Three of them involve the signals 'as is': temporal (a), spectral (b) and time/frequency (c) representations. Three metrics are calculated from weighted power spectral densities of the signals: linear weighting (d), A-weighting (e), and equal-loudness contour at 70 phons [START_REF]Acoustics -normal equal-loudness level contours[END_REF] (f). Weightings for (e) and (f) result from average properties of hearing. The last three metrics were calculated from the output of auditory models. These models have been proposed by Zwicker and Fastl [START_REF] Zwicker | Psychoacoustics: Facts and Models[END_REF] to calculate loudness, and try to model auditory masking. These models analyse the signals in terms of specific loudness, which is the loudness of the signal along the bark scale, i.e. a 'perceptual' frequency scale.

The model involved in the seventh metric takes into account only frequency masking, and evaluates loudness of the signal as a whole, from its overall mean spectrum (g). A more elaborated model takes into account both frequency and temporal masking, calculating the 'time-varying specific loudness' at short time intervals (every 10 ms). Dissimilarities between two specific loudnesses can thus be calculated every 10 ms, and a metric is defined as the temporal integration of this single time-varying dissimilarity (h). The last metric is based on the dissimilarity calculated between the two temporal means of the two time-varying specific loudnesses (i).

Comparison between perceptual and objective results

A comparison can then be made between the dissimilarity matrices resulting from both approaches, which rely on common signal recordings. Subsequent discussions deal with the mean of the results obtained using the three musical excerpts, but it should be noted that the same tendencies are observed on each excerpt. Another approach could thus have been to use physical measurements totally independent of the musical signal, as the frequency response of loudspeakers, but our main concern was to keep the perceptual and objective measurements very close to each other.

Direct comparison of dissimilarities

Correlations between perceptual and objective dissimilarities were calculated for the two channels of each musical excerpt. Fig. 1 shows the average of these correlations.

Dissimilarities based on temporal (a), frequency (b) and time/frequency (c) representations give equivalent results when they are compared to perceptual dissimilarities. This is not surprising, because all three contain the same information on the signal.

When the dissimilarities are evaluated on metrics based on the power spectral density ((d) to (f)), the correlations are higher, suggesting that the information carried by the phase, which is not taken into account in the power spectral density, is not pertinent in relation to our listening conditions. It even seems to mask somewhat the suitable information, as in dissimilarities based on a full representation ((a) to (c), taking into account the phase). The weightings applied to the power spectral density yield a small increase of the correlation for the comparison showed here (see (e) and (f)), but this result was not confirmed by other studies [START_REF] Lavandier | The influence of stereophony on the restitution of timbre by loudspeakers[END_REF][START_REF] Lavandier | Perceptual and physical evaluation of differences among a large panel of loudspeakers[END_REF] and seems to be dependent on the signal [START_REF] Lavandier | The restitution of timbre by loudspeakers in a listening room: perceptual and physical measurements[END_REF].

On Fig. 1, the last three bars correspond to the correlation between perceptual dissimilarities and objective dissimilarities calculated using auditory models. One can observe that taking into account auditory model to evaluate objective dissimilarities greatly improves the correlation with perceptual dissimilarities.

Multidimensional comparison of dissimilarities

Multidimensional scaling analysis (MDS) has been applied to each dissimilarity matrix to build the corresponding spaces [START_REF] Borg | Modern Multidimensional Scaling. Theory and Applications[END_REF]. The MDS is used to represent each loudspeaker in a multidimensional space, so that all the distances between the loudspeakers in this space are as close as possible to the values from the initial dissimilarity matrix. Each dimension of this multidimensional space reveals a significant component of the dissimilarities, although MDS does not provide any interpretation of the underlying nature of these components.

Comparison between MDS analysis of the two matrices resulting from objective and perceptual measurements provides more information than correlation, as it shows if both approaches are using similar components for estimating dissimilarities. It abandons the criterion of linearity to take into account the multidimensional nature of our perception of sound reproduction. The main perceptual dimensions used by listeners to discriminate the recordings are revealed, and the comparison of objective and perceptual spaces tells us if an objective analysis seems appropriate to extract these dimensions from the recordings. On the other hand, such a comparison is done yet only by visual examination, resulting in less reliable conclusions. Fig. 2 (left graphs) shows the 'perceptual spaces' obtained for two excerpts: Kan'nida and Vivaldi. It can be observed that the listeners have used at least two dimensions to differentiate the recordings. The dimension 1, which is predominant, seems to be linked to the bass/treble balance of recordings. The dimension 2 would be linked to the amount of medium frequencies, and could be associated with the notion of sound clarity [START_REF] Lavandier | The restitution of timbre by loudspeakers in a listening room: perceptual and physical measurements[END_REF].

Nine objective spaces (one per metric) have been obtained for each channel of each musical excerpt. Only the metrics based on auditory models that take into account both frequency and temporal masking led to objective spaces similar to the perceptual ones. As an example, Fig. 2 shows objective spaces obtained using the temporal mean of the time-varying specific loudness, for the right channel of Kan'nida and the left channel of Vivaldi. When overall specific loudness is used, the objective and perceptual spaces may differ for some signals. This last result implies that it is important to take into account the temporal variations of the signal during analysis, just as the listeners most probably do.

Conclusion

This research concerns objective and perceptual evaluation of the restitution of timbre by loudspeakers. It shows that auditory models can be used as a tool for signal analysis, in order to define objective metrics that behave similarly to an 'average' listener. The auditory models used here are based on auditory masking and were developed to measure loudness [START_REF] Zwicker | Psychoacoustics: Facts and Models[END_REF]. This study suggests a reason why standard measurements of frequency responses in anechoic environment, usually used to evaluate loudspeakers, cannot be straightforwardly linked to perceptual evaluation: these measurements cannot take into account the time-varying auditory mechanisms responsible for masking effects.

The study does not conclude on the specific contribution of the various aspects of the metrics proposed from auditory models (different ways of summing, time scales, . . . ). More experimental data are needed to clarify these points. Other definitions for metrics could be proposed, and these could lead to an ever tighter link between objective and perceptual measurements. This has also to be developed further.

Fig. 1 .

 1 Fig. 1. Correlation between perceptual and objective dissimilarities averaged within the three musical excerpts: (a) temporal domain, (b) spectral domain, (c) time/frequency domain, (d) power spectral density, (e) A-weighting, (f) equal-loudness at 70 phons weighting, (g) overall specific loudness, (h) time-varying specific loudness, (i) temporal mean of time-varying specific loudness.

Fig. 1 .

 1 Fig. 1. Corrélations entre les différences perceptives et objectives, prises en moyenne sur les trois extraits musicaux : (a) domaine temporel, (b) spectre complexe, (c) plan temps/fréquence, (d) densité spectrale de puissance, (e) spectre pondéré A, (f) spectre pondéré par la courbe isosonique à 70 phones, (g) sonie spécifique globale, (h) moyenne de sonie spécifique instantanée, (i) moyenne temporelle de la sonie spécifique instantanée.

Fig. 2 .

 2 Fig. 2. Perceptual (left) and objective(right) spaces for musical excerpts Kan'nida and Vivaldi. Objective spaces are based on temporal mean of the time-varying specific loudness of the signals. The same scale is used for all space.

Fig. 2 .

 2 Fig. 2. Espaces perceptifs (gauche) et objectifs (droite) pour les extraits musicaux Kan'nida et Vivaldi. Les espaces objectifs sont basés sur la moyenne temporelle de la densité spécifique de sonie instantanée des signaux. Les échelles sont communes à tous les espaces.


Nicolas Nagot

Roselyne Vallo

Vinh Vu

Oanh Khuat

Thi Hai

Delphine Rapoud

Giang Hoang

Pham Catherine Quillet

Minh Khue

Thanh Thi

Tuyet Nham

Alarming tuberculosis rate among people who inject Drug (PWID) in Vietnam

ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

ALARMING TUBERCULOSIS RATE AMONG PEOPLE WHO INJECT DRUGS (PWID) IN VIETNAM

NIDA ROI DA041978 / ANRS 12353 Nicolas Nagot 1 , Vinh Vu Hai 3 , Thuy Dong Thi Thu 2 , Oanh Khuat Thi Hai 4 , Delphine Rapoud 1 , Giang Hoang Thi 5 , Catherine Quillet 1 , Khue Pham Minh 5 , Roselyne Vallo 1 , Thanh Tuyet Thi Nham 4 , Jean-Pierre Moles 1 , Don C Des Jarlais 6 , Lan Nguyen Phuong 2 , Hoi Le 7 , Luan Vo 2 , Huong Duong Thi 5 and Didier Laureillard

Methods

Results

Tuberculosis (TB) remains a major public health threat in South-East Asia despite international and national efforts to reach TB elimination. The epidemic is not homogeneous but presents high transmission clusters, such as People who inject drugs (PWID).

Background

We conducted 2 large community-based respondent-driven sampling (RDS) surveys [1] in October 2016 and October 2017 among PWID, which fueled a prospective cohort of HIV positive participants and a prospective cohort of HIV negative participants who were not on methadone.

The RDS eligibility criteria were: aged 18 years or more, currently injecting drug, positive urine for heroin or methamphetamine and recent skin marks of injection.

The 2 cohorts had similar follow-up visits every 6 months, including questionnaires (sexual behaviors & drug use behaviors), HIV and HCV testing.

The study design was a cross-sectional survey during a cohort followup (12 and 6 months after the first and second RDS, respectively).

Urgent dedicated interventions including large TB

screening, contact tracing of cases, improved referral for care or treatment of latent TB are needed to control TB among PWID, not only to reduce morbidity and mortality, but also to impact on the TB dynamics in the rest of the population. All participants from both cohorts were screened for TB

The screening algorithm started with a set of question on TB symptoms: Fever, cough >1 week, night sweats, weight loss, intense fatigue.

-> If at least one symptom was present, the participants were invited to have a chest X-ray.

-> If the X-ray was abnormal, a sputum was collected for genexpert® MTB/RIF assay -> All participants with a positive genexpert® MTB/RIF were confirmed to be TB infected and were treated according to national guidelines

OUTCOME

-We estimated the prevalence of active TB with a 95% confidence interval.

-In a sensitivity analysis, we assumed that all participants who dropped from the screening cascade had a similar probability to have a confirmed TB than those who completed the screening and we calculated the corrected prevalence of active TB.

Among HIV-positives: 90% were on ART, 82% had a viral load below 1000 copies/mL, their median CD4 count was 472 cells/µL

Figure1. TB algorithm

Conclusion

The prevalence of TB among PWID is very high, ranging from 1.6% to 5.7%. PWID are 30 to 100 times more at risk of active TB than the general population.

Interestingly, the TB burden is very similar between HIV-positive and HIV negative PWID.

In this cross sectional study, we showed that community-based screening was feasible and highly effective to identify TB cases in this hard-to-reach population.

Estimation of TB prevalence:

Conservative approach: HIV positive: 1.8%[95%CI: 0.8;3.5] HIV negative: 1.6%[95%CI: 0.6;3.3] Sensitivity analysis: HIV positive: 4.4%[95%CI: 2.7;6.8] HIV negative: 5.8% [95%CI: 3.8;8.4]

[ 1 ]

 1 Des Jarlais, D.,Duong, H.T., Pham Minh, K., Khuat, O.H.T., Nham, T.T.T., Arasteh, K., Feelemyer, J., Heckathorn, D.D., Peries, M., Moles, J.P., Laureillard, D., Nagot, N., (The Drive Study Team), 2016. Integrated respondent-driven sampling and peer support for persons who inject drugs in Haiphong, Vietnam: a case study with implications for interventions. AIDS Care 28, 1312-1315. https://doi.org/10.

0719 Objective To estimate the prevalence of TB among PWID in Hai Phong city, Vietnam

  1,8 Supporting Community Development Initiatives, Hanoi, Vietnam; 5 Haiphong University of Medicine and Pharmacy, Haiphong, Vietnam; 6 New-York University, NY, USA; 7 National Lung Hospital, National TB control program, Hanoi, Vietnam; 8 Infectious Diseases Department, Caremeau University Hospital, Nîmes, France ;

1 Pathogenesis and control of chronic infections, INSERM, Etablissement Français du Sang, University of Montpellier, Montpellier, France; 2 Friends for International TB relief, Hanoi, Vietnam; 3 Dept of

Infectious and Tropical Diseases, Viet Tiep Hospital, Haiphong, Vietnam; 4

Figure 1. Flow chart of the 2 cohorts

	Table 1. Participant characteristics who have answer the questionnaire:
		HIV negative	HIV positive	Total
		PWID (n=434)	PWID (n=451)	(n=885)
	Socio demographic
	Median age [IQR]	42.5	41.0	42
		[35.0;50.0]	[37.0;45.0]	[36.0;47.0]
	Gender %:
	Female	9.2	5.8	7.5
	Male	90.3	94.2	92.3
	Transgender	0.5	0.0	0.2
	Marital status %:
	Single	27.6	41.9	34.9
	Legally married	34.8	30.2	32.4
	Living in couple	3.9	4.7	4.3
	Divorced/Separated	31.8	21.7	26.7
	Widowed	1.8	1.6	1.7
	Salaried/work %:	82.0	74.5	78.2
	Drug Use in last 6 months
	Heroin use%
	No more	38.2	32.4	35.3
	Recreative only	25.1	36.6	31.0
	Regular/frequent	36.6	31.0	33.8
	On methadone%	50.7	75.2	63.2
	Health%
	Previous TB episode reported 8.6*	33.7	21.4*
	Cough> 1 week	0.6	1.2	0.0
	Night sweats	28.8	37.7	33.3
	Weight loss	17.1	23.1	20.1
	Chest pain/ Difficulty breathing 34.8	41.7	38.3
	Fever	9.2	12.9	11.1
	Fatigue	38.5	49.0	43.8
	* 2 missing value
	References

1080/09540121.2016.1178698


Audrey Monnin

Nicolas Nagot

Marianne Peries

Roselyne Vallo

Nicolas Meda

Mandisa Singata-Madliki

James K Tumwine

Chipepo Kankasa

Pascal Reynier

Thorkild Tylleskär

Lopinavir/ritonavir Induces Mitochondrial Toxicity in HIV-exposed Uninfected Children

à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers,

Lopinavir/ritonavir Induces Mitochondrial Toxicity in HIV-exposed Uninfected Children

Audrey Monnin [START_REF] Aldrovandi | An r etroviral exposure and lymphocyte mtDNA content among uninfected infants of HIV-1-infected mothers[END_REF] , Nicolas Nagot [START_REF] Aldrovandi | An r etroviral exposure and lymphocyte mtDNA content among uninfected infants of HIV-1-infected mothers[END_REF][START_REF] Kohler | A Brief overview of mechanisms of mitochondrial toxicity From NRTIs[END_REF] , Marianne Peries 1 , Roselyne Vallo 1 , Nicolas Meda 3 , Mandisa Singata-Madliki 4 , James K. Tumwine 5 , Chipepo Kankasa 6 , Pascal Reynier 7 , Thorkild Tylleskär 8 , Philippe Van de Perre [START_REF] Aldrovandi | An r etroviral exposure and lymphocyte mtDNA content among uninfected infants of HIV-1-infected mothers[END_REF][START_REF] Kohler | A Brief overview of mechanisms of mitochondrial toxicity From NRTIs[END_REF] , Jean-Pierre Molès [START_REF] Aldrovandi | An r etroviral exposure and lymphocyte mtDNA content among uninfected infants of HIV-1-infected mothers[END_REF] , for the PROMISE PEP consor.um ANR S 12174 1 University of Montpellier, INSERM, EFS, Montpellier, France, 2 CHU Montpellier, Montpellier, France, [START_REF] Nagot | Lopinavir/ritonavir versus Lamivudine peri-exposure prophylaxis to prevent HIV-1 transmission by breas eeding: the PROMISE-PEP trial Protocol ANRS 12174[END_REF] University of Ouagadougou, Ouagadougou, Burkina Faso, 4 University of Fort Hare, East London, South Africa, 5 University of Makerere, Kampala, Uganda, 6 University Teaching Hospital, Lusaka, Zambia, 7 CHU Angers, Angers, France, 8 University of Bergen, Bergen, Norway Mitochondrial DNA copy number at day 7 and a er one year of PrEP  Overall, the mtDNA copy number per cell markedly decreased a er one year of prophylac c treatment and irrespec v e of the drug used.

 Children from Burkina Faso and Uganda presented similar levels of mtDNA copy number per cell at W50. Children from Zambia showed the highest whereas those from South Africa showed the lowest.

A er adjustment, LPV/r treatment was associated with a mtDNA deple on a er one year of PrEP.

 Overall, the propor on of deleted mtDNA remained unchanged a er one year of prophylac c treatment, despite being high at day 7.

Propor on of dele ted mtDNA at day 7 and a er one year of PrEP

 Adverse outcomes in HIV-exposed uninfected (HEU) children have been reported, including mitochondrial toxicity (1).

 HEU children are exposed to HIV and ARV during the pregnancy and breas eeding periods.

 Pre-exposure prophylaxis (PrEP) is widely deployed in popula ons at risk of acquiring HIV but s ll not widely promoted among HEU children.

 Beside the well-known side e ect of NRTI on mitochondria (2), protease inhibitors such as LPV/r were not reported to be mitotoxic.  At day seven (D7), children were randomized to receive either 3TC or LPV/r as PrEP un l the end of breas eeding (max 50 weeks W50).

 Children from Burkina Faso and Uganda presented the highest rates of deleted mtDNA, children from Zambia and South Africa the lowest. Seven children (5 in the LPV/r arm and 2 in the 3TC arm), all in Burkina Faso, presented a dele on r ate over 40% (red dots•).  We used de ni ons of mitochondrial DNA parameters according to a reference center for mitochondrial disorders :

-mtDNA deple on at W50 was de ned by a mtDNA copy number per cell (mtDNA) 30% lower than its value at D7.

-% deleted mtDNA at W50 was considered at risk when it exceeds 40%.

 Wilcoxon rank test was used to compare con nous variables.

Mul v ariate logis c regression were performed to iden f y the risk factors associated with a mtDNA deple on and an increase propor on of deleted mtDNA at W50. qPCR mtDNA copy number qPCR % deleted mtDNA  14.9% of children (19.6% in the LPV/r arm and 10.6% in the 3TC arm) presented a mtDNA deple on, the vast majority of them were in South Africa. There was signi c antly more children with a mtDNA deple on for the LPV/r treatment in this site compared to the 3TC one.

Burkina Faso Uganda South Africa Zambia

During the follow-up, 51.8% of children presented an increase in the propor on of deleted mtDNA (55.3% in the LPV/r arm and 44.7% in the 3TC arm).



  The aim of this study was to quan f y the mitochondrial toxicity of lopinavir/ritonavir (LPV/r) and lamivudine (3TC) used as PrEP among breas ed HEU children.  201 children from the ANRS 12174 trial were randomly included in this study with a sex and treatment ra o ar ound 1.  The ANRS 12174 trial was conducted in four african countries (Burkina Faso, South Africa, Uganda and Zambia) between 2009 and 2014. 1273 breas ed HEU children born to HIV-infected mothers were recruited (3).



  design. PMTCT, preven o n of mother-to-child transmission  A marked decrease of mtDNA copy number per cell was observed in children under PrEP, significantly and independently more important for those taking LPV/r regimen. Unexpectedly, the proportion of deleted mtDNA, assessed for the first time in this population, was high at birth and remained unchanged at the end of the prophylaxis period.  Mitochondrial toxicity of LPV/r came as a surprise since LPV/r was not reported as responsible for this adverse event in the literature. At an individual level, whether none of the children included in this study presented any clinical symptom of mitochondrial diseases, several of them showed level of mtDNA content and/or level of deleted mtDNA consistent with mitochondrial disorders.  Because mitochondrial toxicity in HEU children was reported to be persistent until 3 years and reversible in some circumstances, This work was funded by the Pierre Bergé endowment fund in collabora.o n with Sidac on and sponsored by the French Na o nal Agency for Research on AIDS and Viral Hepa s [ANRS#12174].



  Photo credit:Shu erstock

Risk factors associated with a mtDNA deple.on a er one year of PrEP

	Independent variable	OR	95% CI p value AOR	95% CI p value
	Gender
	Boy versus Girl	1.44 0.66-3.19	0.36
	Site
	Burkina Faso versus Zambia	5.44 0.61-48.40		6.33 0.70-57.61
	South Africa versus Zambia	33.19 4.25-259.3	<0.01	49.94 6.05-412.5 <0.01
	Uganda versus Zambia	3.20 0.32-31.83		4.22 0.41-43.55
	PrEP
	LPV/r versus 3TC	2.06 0.95-4.59	0.08	3.

OR, odd ra.o; A OR, adjusted odd ra o; CI, con dence interval

13 1.22-8.04 0.02 Dura o n of pre-partum maternal ARV treatment (weeks

) 1.09 1.01-1.17 0.

02 Dura o n of breas eeding (weeks)

	0.97 0.94-1.01	0.11

Mother plasma HIV RNA (copies/mL)

	Uncontrolled (≥1000) versus Controlled (<1000) at D7	1.70 0.78-3.71	0.18	2.22 0.89-5.49 0.09
	Uncontrolled (≥1000) versus Controlled (<1000) at W38 1.11 0.48-2.57	0.81

Gesta onnal ag e (weeks) 0

.88 0.70-1.10 0.

26 Weight of the baby at D7 (kg) 0

.58 0.24-1.43 0.

24 Haemoglobin concentra on a t D7 (g/dL) 1

.00 0.93-1.07 0.98

factors associated with an increase deleted mtDNA rate a er one year of PrEP

					Poster #878
	Burkina Faso	Uganda		Zambia	South Africa
	Independent variable		OR	95% CI	p value AOR 95% CI p value
	Gender
	Boy versus Girl		0.98 0.56-1.70	0.93
	Site
	Burkina Faso versus South Africa		3.75 1.64-8.59	2.99 1.27-7.04
	<0.01 0.10 1.42 0.79-2.57 0.25 3.88 1.70-8.85 <0.01 4.04 1.73-9.45 1.75 0.79-3.92 1.69 0.74-3.85 1.60 0.91-2.80 Dura o n of pre-partum maternal ARV treatment (weeks) 0.99 0.93-1.04 Uganda versus South Africa Zambia versus South Africa PrEP LPV/r versus 3TC 0.61 Dura o n of breas eeding (weeks) 1.00 0.98-1.03 0.89	A er adjustment, LPV/r treatment was not associ-ated with an increase pro-por on of deleted mtDNA a er one year of PrEP.
	Mother plasma HIV RNA (copies/mL)
	Uncontrolled (≥1000) versus Controlled (<1000) at D7	0.91 0.52-1.59	0.76
	Uncontrolled (≥1000) versus Controlled (<1000) at W38 0.64 0.35-1.16	0.14 0.42 0.20-0.88 0.02
	Gesta onnal ag e (weeks)		1.05 0.89-1.24	0.58
	Weight of the baby at D7 (kg)		0.39 0.20-0.78	0.01 0.37 0.18-0.75 0.01
	Haemoglobin concentra on ( g/dL)		0.99 0.95-1.04	0.70

Presented at the 25th Conference on Retroviruses and Opportunis c I nfec ons, March 4-7, 2018, Boston, United States of America Risk OR, odd ra o; A OR, adjusted odd ra o; CI, con dence interval