Abstract: Domestic dogs are unique from other animal models of cancer in that they generally experience spontaneous disease. In addition, most types of cancer observed in humans are found in dogs, suggesting that canines may be an informative system for the study of cancer genetics. Domestic dogs are divided into over 175 breeds, with members of each breed sharing significant phenotypes. The breed barrier enhances the utility of the model, especially for genetic studies where small numbers of genes are hypothesized to account for the breed cancer susceptibility. These facts, combined with recent advances in high-throughput sequencing technologies allows for an unrivaled ability to use pet dog populations to find often subtle mutations that promote cancer susceptibility and progression in dogs as a whole. The meticulous record keeping associated with dog breeding makes the model still more powerful, as it facilitates both association analysis and family-based linkage studies. Key to the success of these studies is their cooperative nature, with owners, scientists, veterinarians and breed clubs working together to avoid the cost and unpopularity of developing captive populations. In this article we explore these principals and advocate for colony-free, genetic studies that will enhance our ability to diagnose and treat cancer in dogs and humans alike.

Abstract: This study examined the fecal bacterial diversity of 15-weekold pigs from three purebred lines: Duroc, Landrace, and Yorkshire. Taxon-dependent and -independent analyses were performed to evaluate differences in the fecal bacterial communities and to identify bacterial genera that can be used to discriminate breeds, following high-throughput pyrosequencing of 16S rRNA genes. Among the breeds evaluated, Landrace had the most diverse bacterial community composition. Prevotella, Blautia, Oscillibacter, and Clostridium were detected in all samples regardless of breed. On the other hand, Catenibacterium, Blautia, Dialister, and Sphaerochaeta were differentially detected among breeds, as demonstrated by the canonical loading plot. The discriminant analysis of principal components plot also showed clear separation of the three purebred pig lines, with a certain degree of similarity between Landrace and Yorkshire pigs and a distinct separation between Duroc pigs and the other two breeds. Other factors not related to breed, such as season or time of sampling and pen effects, may contribute to shaping the gut microbiota of pigs.

Abstract: Iteroparity is an adaptive response to uncertainty in reproductive success. However, spreading reproductive success over multiple reproduction events during a lifetime is constrained by adult mortality and the stochasticity associated with interactions between external factors and physiological states. The acquisition of information about environmental conditions during the growth of progeny and sufficient resources during the non-reproductive period are key factors for breeding success. Consequently, we hypothesized that long-lived animals may skip a breeding opportunity when information about unfavourable environmental conditions is available. In addition, nutritional constraints could prevent an animal from replenishing its reserves sufficiently to invest in the current breeding period. We investigated these questions using capture–recapture data from a 5-year study on a large population of yellow-bellied toads in a forest in north-eastern France. We took advantage of various advances in multi-state capture–recapture models (e.g. unobservable states and mixture models) to test our hypotheses. Our results show that the combined effects of rainfall deficit and the breeding/non-breeding state of individuals during the past breeding season affect breeding probability during the following breeding opportunity. We also found that females breed less frequently than males, suggesting that the overall energy cost of reproduction differs between genders. Finally, the results indicate that toad survival appears to be negatively influenced by rainfall deficits. We discuss the yellow-bellied toad’s reproductive behaviour in term of bet-hedging strategy and life history trait evolution.

Abstract: Although differences in breeding lifespan are an important source of variation in male fitness, the factors affecting the breeding tenure of males have seldom been explored. Here, we use cross-species comparisons to investigate the correlates of breeding lifespan in male mammals. Our results show that male breeding lifespan depends on the extent of polygyny, which reflects the relative intensity of competition for access to females. Males have relatively short breeding tenure in species where individuals have the potential to monopolize mating with multiple females, and longer ones where individuals defend one female at a time. Male breeding tenure is also shorter in species in which females breed frequently than in those where females breed less frequently, suggesting that the costs of guarding females may contribute to limiting tenure length. As a consequence of these relationships, estimates of skew in male breeding success within seasons overestimate skew calculated across the lifetime and, in several polygynous species, variance in lifetime breeding success is not substantially higher in males than in females.

Abstract: Data from 9296 calves born to 2078 dams over 9 years across five sites were used to investigate factors associated with calf mortality for tropically adapted breeds (Brahman and Tropical Composite) recorded in extensive production systems, using multivariate logistic regression. The average calf mortality pre-weaning was 9.5% of calves born, varying from 1.5% to 41% across all sites and years. In total, 67% of calves that died did so within a week of their birth, with cause of death most frequently recorded as unknown. The major factors significantly (P < 0.05) associated with mortality for potentially large numbers of calves included the specific production environment represented by site-year, low calf birthweight (more so than high birthweight) and horn status at branding. Almost all calf deaths post-branding (assessed from n = 8348 calves) occurred in calves that were dehorned, totalling 2.1% of dehorned calves and 15.9% of all calf deaths recorded. Breed effects on calf mortality were primarily the result of breed differences in calf birthweight and, to a lesser extent, large teat size of cows; however, differences in other breed characteristics could be important. Twin births and calves assisted at birth had a very high risk of mortality, but <1% of calves were twins and few calves were assisted at birth. Conversely, it could not be established how many calves would have benefitted from assistance at birth. Cow age group and outcome from the previous season were also associated with current calf mortality; maiden or young cows (<4 years old) had increased calf losses overall. More mature cows with a previous outcome of calf loss were also more likely to have another calf loss in the subsequent year, and this should be considered for culling decisions. Closer attention to the management of younger cows is warranted to improve calf survival.

Abstract: The aim of the present study was to demonstrate the influence of boar breed and season on semen parameters. The research material consisted of 31 boars: Polish Large White (PLW), Polish Landrace (PL), and Duroc × Pietrain (D × P), aged 8 to 24 months. The analysed material consisted of 1390 ejaculates, collected during the period January 2010 to October 2012. Semen samples were assessed in terms of semen volume (mL), sperm concentration (× 10 6 m/mL), total number of sperm (× 10 9 ), total number of live sperm (× 10 9 ) and number of insemination doses obtained from one ejaculate (n). In winter, an increase in sperm concentration was observed for the PLW breed. Moreover, an increase in the volume of semen produced for this breed was noted in summer and autumn. Differences between breeds for the total number of sperm and total number of live sperm were observed for the winter and spring periods. The largest semen volume was noted for the PLW breed (276.4 ± 9.66 mL). However, in the analysis of other sperm parameters, boars of this breed demonstrated the poorest results. The highest insemination dose was obtained from breed D × P in winter (26.0 ± 0.51). Correlation analyses indicated that PLW and D × P boars are the least resistant to higher ambient temperatures, and in summer and autumn this resulted in a reduction in sperm concentration (–0.26 and –0.20, respectively). Keywords: Breed, boars, ejaculate, season, semen quality

Abstract: The objective of the study was to determine the effects of animal related factors on bruising in slaughter cattle, creatine kinase (CK) and beef quality. Three hundred and twenty one cattle from three breeds (108 Bonsmara, 130 Beefmaster and 83 Brahman) were used in this study. The animals were grouped as follows: Group 1 (16 months old), Group 2 (18 months old) and Group 3 (24 months old). At exsanguinations, blood samples for CK determination were collected using disposable vacutainer tubes. Muscularis longissimus thoracis et lumborum (LTL) was collected 24 h after slaughter to determine the colour (L*, a*, and b*) and ultimate pH (pHu) of beef. Breed, sex and age had significant effects (p<0.05) on bruising score, CK levels and beef quality. Bonsmara breed had the highest (80%) bruising score percentage, CK (705.3±80.57 U/L) and pHu (6.3±0.05) values while the Bonsmara had the highest L* (24.8±0.78) a* (17.5±0.53) and b* (12.8±0.53) values. Higher CK levels were also observed in winter compared to summer, spring and autumn respectively. Therefore, animal factors (sex, breed and animal age at slaughter) contribute to the development of bruises and have an effect on the levels of CK and meat quality. It was also concluded that there is no significant relationship between meat parameters (L,* a*, and b*) and CK levels.

Abstract: The objective of this study was to evaluate, using three different genotype density panels, the accuracy of imputation from lower- to higher-density genotypes in dairy and beef cattle. High-density genotypes consisting of 777,962 single-nucleotide polymorphisms (SNP) were available on 3122 animals comprised of 269, 196, 710, 234, 719, 730 and 264 Angus, Belgian Blue, Charolais, Hereford, Holstein-Friesian, Limousin and Simmental bulls, respectively. Three different genotype densities were generated: low density (LD; 6501 autosomal SNPs), medium density (50K; 47,770 autosomal SNPs) and high density (HD; 735,151 autosomal SNPs). Imputation from lower- to higher-density genotype platforms was undertaken within and across breeds exploiting population-wide linkage disequilibrium. The mean allele concordance rate per breed from LD to HD when undertaken using a single breed or multiple breed reference population varied from 0.956 to 0.974 and from 0.947 to 0.967, respectively. The mean allele concordance rate per breed from 50K to HD when undertaken using a single breed or multiple breed reference population varied from 0.987 to 0.994 and from 0.987 to 0.993, respectively. The accuracy of imputation was generally greater when the reference population was solely comprised of the breed to be imputed compared to when the reference population comprised of multiple breeds, although the impact was less when imputing from 50K to HD compared to imputing from LD.

Abstract: The aim of genomic prediction is to pre- dict breeding value from genomic data. We describe the development of genomic prediction equations and accu- racies for molecular breeding values (MBV) for indus- try use, focusing on the methodology used to deal with predictions for the New Zealand sheep population struc- ture. This is made up of a mixture of pure and crossbred animals, but principally Romney based. In particular, we used pedigree-based EBV for 8 traits (weaning weight as a direct effect, weaning weight as a maternal effect, live weight at 8 mo, live weight at 12 mo, greasy fleece weight at 12 mo, lamb fleece weight, adult fleece weight, and number of lambs born) and Illumina OvineSNP50 BeadChip genotypes from 13,420 animals to investi- gate BLUP with different genomic relationship matrices (GRM) based on SNP markers and to investigate varying sets of older animals (training sets) to predict the MBV of younger animals (validation sets). The GRM tested included modifications to account for allele frequency differences between breeds, rescaling so that the mean GRM is equal to the mean of the traditional pedigree numerator relationship matrix A, and combining of the GRM with A using a convex combination with a weight estimated by maximizing a conditional restricted likeli- hood. We found that these modifications were beneficial and recommend using a breed-adjusted GRM combined with A. Training data sets with Romney, Coopworth, and Perendale animals all together usually predicted bet- ter than using just a pure breed training data set for all traits. But predictions for the breed Perendale were more accurate with a Perendale training set for 3 of the 8 traits. We concluded that using a mixed-breed training set for all combinations of traits and breeds was best but advise that increasing the number of Perendale animals geno- typed should be a priority to increase the MBV accura- cies obtained for that breed.

Abstract: The accuracy of genomic prediction depends largely on the number of animals with phenotypes and genotypes. In some industries, such as sheep and beef cattle, data are often available from a mixture of breeds, multiple strains within a breed or from crossbred animals. The objective of this study was to compare the accuracy of genomic prediction for several economically important traits in sheep when using data from purebreds, crossbreds or a combination of those in a reference population. The reference populations were purebred Merinos, crossbreds of Border Leicester (BL), Poll Dorset (PD) or White Suffolk (WS) with Merinos and combinations of purebred and crossbred animals. Genomic breeding values (GBV) were calculated based on genomic best linear unbiased prediction (GBLUP), using a genomic relationship matrix calculated based on 48 599 Ovine SNP (single nucleotide polymorphisms) genotypes. The accuracy of GBV was assessed in a group of purebred industry sires based on the correlation coefficient between GBV and accurate estimated breeding values based on progeny records. The accuracy of GBV for Merino sires increased with a larger purebred Merino reference population, but decreased when a large purebred Merino reference population was augmented with records from crossbred animals. The GBV accuracy for BL, PD and WS breeds based on crossbred data was the same or tended to decrease when more purebred Merinos were added to the crossbred reference population. The prediction accuracy for a particular breed was close to zero when the reference population did not contain any haplotypes of the target breed, except for some low accuracies that were obtained when predicting PD from WS and vice versa. This study demonstrates that crossbred animals can be used for genomic prediction of purebred animals using 50 k SNP marker density and GBLUP, but crossbred data provided lower accuracy than purebred data. Including data from distant breeds in a reference population had a neutral to slightly negative effect on the accuracy of genomic prediction. Accounting for differences in marker allele frequencies between breeds had only a small effect on the accuracy of genomic prediction from crossbred or combined crossbred and purebred reference populations.

Abstract: The recent availability of sheep genome-wide SNP panels allows providing background information concerning genome structure in domestic animals. The aim of this work was to investigate the patterns of linkage disequilibrium (LD), the genetic diversity and population structure in Valle del Belice, Comisana, and Pinzirita dairy sheep breeds using the Illumina Ovine SNP50K Genotyping array. Average r 2 between adjacent SNPs across all chromosomes was 0.155 ± 0.204 for Valle del Belice, 0.156 ± 0.208 for Comisana, and 0.128 ± 0.188 for Pinzirita breeds, and some variations in LD value across chromosomes were observed, in particular for Valle del Belice and Comisana breeds. Average values of r 2 estimated for all pairwise combinations of SNPs pooled over all autosomes were 0.058 ± 0.023 for Valle del Belice, 0.056 ± 0.021 for Comisana, and 0.037 ± 0.017 for Pinzirita breeds. The LD declined as a function of distance and average r 2 was lower than the values observed in other sheep breeds. Consistency of results among the several used approaches (Principal component analysis, Bayesian clustering, FST, Neighbor networks) showed that while Valle del Belice and Pinzirita breeds formed a unique cluster, Comisana breed showed the presence of substructure. In Valle del Belice breed, the high level of genetic differentiation within breed, the heterogeneous cluster in Admixture analysis, but at the same time the highest inbreeding coefficient, suggested that the breed had a wide genetic base with inbred individuals belonging to the same flock. The Sicilian breeds were characterized by low genetic differentiation and high level of admixture. Pinzirita breed displayed the highest genetic diversity (He, Ne) whereas the lowest value was found in Valle del Belice breed. This study has reported for the first time estimates of LD and genetic diversity from a genome-wide perspective in Sicilian dairy sheep breeds. Our results indicate that breeds formed non-overlapping clusters and are clearly separated populations and that Comisana sheep breed does not constitute a homogenous population. The information generated from this study has important implications for the design and applications of association studies as well as for development of conservation and/or selection breeding programs.

Abstract: Bull breeds are commonly kept as companion animals, but the pit bull terrier is restricted by breed-specific legislation (BSL) in parts of the United States and throughout the United Kingdom. Shelter workers must decide which breed(s) a dog is. This decision may influence the dog's fate, particularly in places with BSL. In this study, shelter workers in the United States and United Kingdom were shown pictures of 20 dogs and were asked what breed each dog was, how they determined each dog's breed, whether each dog was a pit bull, and what they expected the fate of each dog to be. There was much variation in responses both between and within the United States and United Kingdom. UK participants frequently labeled dogs commonly considered by U.S. participants to be pit bulls as Staffordshire bull terriers. UK participants were more likely to say their shelters would euthanize dogs deemed to be pit bulls. Most participants noted using dogs' physical features to determine breed, and 41% affected by BSL indicated they would knowingly mislabel a dog of a restricted breed, presumably to increase the dog's adoption chances.

Abstract: The Marchigiana is famous for its large body size and favorable dressing percentage. A myostatin (MSTN) gene mutation (a G to T transversion) was identified in the breed. The homozygote "GG" yields a "normal" phenotype, the homozygote "TT" yields a double muscled body shape but sometimes causes survival problems, and the heterozygote genotype produces an extremely muscled body without defects. In practice, Marchigiana "TT" homozygotes are culled from reproduction, but the heterozygotes are chosen as sires. The objective of this study was to assess genes involved in Marchigiana muscle development to improve selection procedures. The effects of the MSTN and myogenic factor 5 (MYF5) genes on the growth and muscle traits in the Marchigiana breed were assessed. The effects of MSTN together with the genotype of the causative mutation (g.874G > T) and the effects of the two SNP in the promoter were studied (g.-371T > A and g.-805G > C). The SNP effects were evaluated in a comparison between the means of the several genotypes or for the average gene substitution and dominance effect. Two hundred forty-nine bullocks were evaluated using a performance test. At the beginning and end of the trial, the animals were weighed and their bodies were measured every 21 d up to 12 mo of age. In addition to these observations, morphological scores and the BLUP indices were estimated at the end of the performance test. The obtained results suggested that the MSTN g.874G > T and MYF5 SNP could be considered in the selection program of the Marchigiana breed. A MSTN g.874G > T genotyping service for the breeders could help to avoid the "TT" genotype and to select for the "GT" genotype. The "AA" MYF5 SNP genotype could also be selected for even if good muscle development yields a certain size reduction.

Abstract: A cross sectional study was conducted from July to October 2013 to estimate prevalence and identify different species of ectoparasites infesting chicken in semi-intensive and backyard chicken farms in and around Ambo Town, West Shewa, Ethiopia. A total of 390 chickens were randomly selected. Age, sex, breed and management system of the study population was simultaneously recorded. Ectoparasites were collected from different parts of the body including shank scraping and identified with stereomicroscopy or light microscopy. An overall 67.95% (265/390) prevalence was recorded and five species of ectoparasites under three orders (Phthiraptera (lice), Siphonaptera (flea) and mite were identified. The prevalence of pediculosis, flea infestation and mange were 52.1%, 44.36% and 34.62%, respectively. Three species of lice (Cuclotogaster heterographa (50%), Menacanthus stramineus (1.28%) and Lipeurus caponis (6.15%)), one species of flea (Echidnophaga gallinacean (44.36%)) and mite (Cnemidocoptes mutans (34.62%)) were identified. Higher prevalence rate was recorded in male (83.89%) than female (58.09%), young (74.45%) than adult (61.79%) and local (87.55%) than exotic (26.4%) breed chicken. There was no infestation of chicken with ectoparasite in semi-intensive farming system while 87.46% (265/303) of chickens kept under extensive management system were infested. Statistically, there was significance difference between categories of sex (χ2=28.145, p<0.05), age (χ2=8.083, p<0.05), management (χ2=2.37, p<0.05) and breed (χ2=1.458, p<0.05) groups in prevalence of ectoparasite infestation (p<0.05). Male, young and local breed chicken groups were 3.757 (CI=2.265-6.234), 1.883 (CI=1.214-2.921) and 19.6 (11.427-33.618) times more likely infested by ectoparasite than female, adult and cross breed groups, respectively. In conclusion, infestation of chicken with ectoparasites was important constraint in poultry production sector. Therefore, application of integrated control strategy, good management practices, creation of awareness and further detailed study were recommended.

Abstract: Improving the traits that underlie meat quality is a major challenge in the beef industry. The objective of this paper was to detect QTL linked to sensory meat quality traits in 3 French beef cattle breeds. We genotyped 1,059, 1,219, and 947 young bulls and their sires belonging to the Charolais, Limousin, and Blonde d'Aquitaine breeds, respectively, using the Illumina BovineSNP50 BeadChip (Illumina Inc., San Diego, CA). After estimating relevant genetic parameters using VCE software, we performed a linkage disequilibrium and linkage analysis on 4 meat traits: intramuscular fat content, muscle lightness, shear force, and tenderness score. Heritability coefficients largely ranged between 0.10 and 0.24; however, they reached a maximum of 0.44 and 0.50 for intramuscular fat content and tenderness score, respectively, in the Charolais breed. The 2 meat texture traits, shear force and tenderness score, were strongly genetically correlated (-0.91 in the Charolais and Limousin breed and -0.86 in the Blonde d'Aquitaine breed), indicating that they are 2 different measures of approximately the same trait. The genetic correlation between tenderness and intramuscular fat content differed across breeds. Using a significance threshold of 5 × 10(-4) for QTL detection, we found more than 200 significant positions across the 29 autosomal chromosomes for the 4 traits in the Charolais and Blonde d'Aquitaine breeds; in contrast, there were only 78 significant positions in the Limousin breed. Few QTL were common across breeds. We detected QTL for intramuscular fat content located near the myostatin gene in the Charolais and Blonde d'Aquitaine breeds. No mutation in this gene has been reported for the Blonde d'Aquitaine breed; therefore, it suggests that an unknown mutation could be segregating in this breed. We confirmed that, in certain breeds, markers in the calpastatin and calpain 1 gene regions affect tenderness. We also found new QTL as several QTL on chromosome 3 that are significantly associated with meat tenderness in the Blonde d'Aquitaine breed. Overall, these results greatly contribute to the goal of building a panel of markers that can be used to select animals of high meat quality.

Abstract: Poor udder health represents a serious problem in dairy production and has been investigated intensively, but heifers generally have not been the main focus of mastitis control. The aim of this study was to evaluate the prevalence, risk factors and consequences of heifer mastitis in Switzerland. The study included 166,518 heifers of different breeds (Swiss Red Pied, Swiss Brown Cattle and Holstein). Monthly somatic cell counts (SCCs) provided by the main dairy breeding organisations in Switzerland were monitored for 3 years; the prevalence of subclinical mastitis (SCM) was determined on the basis of SCCs ≥100,000 cells/mL at the first test date. The probability of having SCM at the first test date during lactation was modelled using logistic regression. Analysed factors included data for the genetic background, morphological traits, geographical region, season of parturition and milk composition. The overall prevalence of SCM in heifers during the period from 2006 to 2010 was 20.6%. Higher frequencies of SCM were present in heifers of the Holstein breed (odds ratio, OR, 1.62), heifers with high fat:protein ratios (OR 1.97) and heifers with low milk urea concentrations combined with high milk protein concentrations (OR 3.97). Traits associated with a low risk of SCM were high set udders, high overall breeding values and low milk breeding values. Heifers with SCM on the first test day had a higher risk of either developing chronic mastitis or leaving the herd prematurely.

Abstract: This paper reviews two factors (breed and feed) affecting the carcass and meat quality of sheep. The quality of livestock products has acquired greater importance from the distinct perspectives of the different participants in the agricultural food chain. Consumers, producers and the industry give different levels of importance to the parameters of meat and carcass quality. Nevertheless, all the participants in the meat production chain must ensure quality to improve their competitiveness. The quality of the carcass and meat can be influenced by different factors such as breed and type of feed. The breed can influence weight, yields, and the conformation of the carcass, among other variables, as well as the pH level and the fatty acid composition of the meat, whereas the feed mainly affects carcass conformation and several physicochemical and organoleptic parameters of meat quality such as proximal composition, the fatty acid profile, tenderness and color. Consequently, the effects of breed and feed type should be considered to obtain a quality product that satisfies consumer demand.

Abstract: Genomic technologies, such as high- throughput genotyping based on SNP arrays, provided background information concerning genome structure in domestic animals. The aim of this work was to inves- tigate the genetic structure, the genome-wide estimates of inbreeding, coancestry, effective population size (N e ), and the patterns of linkage disequilibrium (LD) in 2 eco- nomically important Sicilian local cattle breeds, Cinisara (CIN) and Modicana (MOD), using the Illumina Bovine SNP50K v2 BeadChip. To understand the genetic rela- tionship and to place both Sicilian breeds in a global context, genotypes from 134 other domesticated bovid breeds were used. Principal component analysis showed that the Sicilian cattle breeds were closer to individuals of Bos taurus taurus from Eurasia and formed non- overlapping clusters with other breeds. Between the Sicilian cattle breeds, MOD was the most differentiated, whereas the animals belonging to the CIN breed showed a lower value of assignment, the presence of substruc- ture, and genetic links with the MOD breed. The average molecular inbreeding and coancestry coefficients were moderately high, and the current estimates of N e were low in both breeds. These values indicated a low genetic variability. Considering levels of LD between adjacent markers, the average r 2 in the MOD breed was compa- rable to those reported for others cattle breeds, whereas CIN showed a lower value. Therefore, these results sup- port the need of more dense SNP arrays for a high-power association mapping and genomic selection efficiency, particularly for the CIN cattle breed. Controlling molec- ular inbreeding and coancestry would restrict inbreeding depression, the probability of losing beneficial rare alleles, and therefore the risk of extinction. The results generated from this study have important implications for the development of conservation and/or selection breeding programs in these 2 local cattle breeds.

Abstract: Most donkey and local horse breeds are vulnerable to extinction as mechanization of agriculture progress throughout the world. The present study analyzed the pedigree and herd records of the donkey Asinina de Miranda breed (RAM), identifying genealogical and human factors that may affect the breed genetic diversity in the future and suggesting suitable strategies to breed preservation, early on the conservation program. The breeding rate was very low, with a ratio of foaling/live animals of 0.23 (178/760). The estimated number of founders and ancestors contributing to the reference population was 128 and 121. The number of founder herds in the reference population was 64, with an effective number of founder herds for the reference population of 7.6. The mean age of herd owners was 65.50±0.884 years, with a negative association among the herd size and owner’s age (P<0.001). In contrast, the size of the herd and the ownership of a male were both positively associated (P<0.001) with the herd number of in-born foals. Both the owners’ age and the herd location (RAM home region v. dispersal region) were negatively associated with the foaling number (P<0.001). The main identified risk factors were: low breeding rates; low number of males and their unequal contribution to the genetic pool; unequal contribution of the herds to genetic pool; and advanced age of herd owners.