A5088472236- Genetic and phenotypic traits in livestock
- Agriculture and Rural Development Research
- Milk Quality and Mastitis in Dairy Cows
- Genetic Mapping and Diversity in Plants and Animals
- Effects of Environmental Stressors on Livestock
- Agriculture Sustainability and Environmental Impact
- Reproductive Physiology in Livestock
- Animal Genetics and Reproduction
- Prion Diseases and Protein Misfolding
- Animal Behavior and Welfare Studies
- Ruminant Nutrition and Digestive Physiology
- Livestock Farming and Management
- French Urban and Social Studies
- Meat and Animal Product Quality
- Rangeland Management and Livestock Ecology
- Helminth infection and control
- Cancer-related molecular mechanisms research
- Food Supply Chain Traceability
- Genetic diversity and population structure
- Genetics and Plant Breeding
- Wheat and Barley Genetics and Pathology
- Animal Nutrition and Physiology
- Coccidia and coccidiosis research
- Insects and Parasite Interactions
- Animal Diversity and Health Studies
Institut de l’Elevage
2016-2025
Génétique Physiologie et Systèmes d'Elevage
1996-2022
Département Biologie et Amélioration des Plantes
2002-2013
BP (France)
2010
Weatherford College
2000
University of Aberdeen
1975
Dar al Athar al Islamiyyah
1975
United States Department of the Army
1975
Cardinal Health (Australia)
1975
St. Augustine College
1975
Abstract Background Bias has been reported in genetic or genomic evaluations of several species. Common biases are systematic differences between averages estimated and true breeding values, their over- under-dispersion. In addition, comparing accuracies pedigree versus predictions is a difficult task. This work proposes to analyse the evaluation milk yield Manech Tête Rousse dairy sheep, over years, by testing five models using estimators linear regression method. We tested with without...
Abstract Recombination is a complex biological process that results from cascade of multiple events during meiosis. Understanding the genetic determinism recombination can help to understand if and how these are interacting. To tackle this question, we studied patterns in sheep, using approaches data sets. We constructed male maps dairy breed south France (the Lacaune breed) at fine scale by combining meiotic rates large pedigree genotyped with 50K SNP array historical sample unrelated...
Breeding sheep for enhanced resistance to gastrointestinal parasites is a promising strategy limit the use of anthelmintics due now widespread these molecules. This paper reports genetic parameters estimated parasite and resilience traits in Blond-faced Manech dairy breed putative impacts selection nematodes (GIN) on farms. Two datasets were used. First, rams scheme artificially infected twice with L3 Haemonchus contortus larvae. Faecal egg counts (FEC) packed cell volume (PCV) loss measured...
(1) Background: Sheep have been selected to improve their milk production. Some local dairy breeds, such as the Blond-Faced Manech (BFM) in south-west France, also select for resistance mastitis and gastro-intestinal nematodes. However, genetic selection can deteriorate certain traits, benefit of improving others. Breeders are particularly concerned about infections by digestive protozoa Cryptosporidium Eimeria genus, which infect lambs at an early age compromise future careers. (2) Methods:...
The objective of the study was two-fold and is as follows: (i) to investigate genotype-by-environment (G × E) interactions for milk yield composition in purebred Lacaune sheep reared intensively Greece semi-extensively France, (ii) estimate potential genetic gain selection based on evaluations jointly calculated both countries compared each country separately. A total 1658 ewes from 4 intensive farms Northern 4859 186 semi-extensive Southern France were used. Ewes two daughters or...
In conventional small ruminant breeding programs, only pedigree and phenotype records are used to make selection decisions but prospects of including genomic information now under consideration. The objective this study was assess the potential benefits on genetic gain in French sheep goat designs today. Traditional scenarios were modeled with deterministic methods for 3 programs. models included decisional variables related male candidates, progeny testing capacity, economic weights that...
Recent genomic evaluation studies using real data and predicting genetic gain by modeling breeding programs have reported moderate expected benefits from the replacement of classic selection schemes (GS) in small ruminants. The objectives this study were to compare cost, monetary economic efficiency GS meat sheep industry. Deterministic methods used model based on multi-trait indices a program. Decisional variables related male candidates progeny testing optimized maximize annual (AMGG),...
Homozygous recessive deleterious mutations can cause embryo/fetal or neonatal lethality, genetic defects that affect female fertility and animal welfare. In livestock populations under selection, the frequency of such lethal may increase due to inbreeding, drift, and/or positive pleiotropic effects heterozygous carriers on selected traits.By scanning genome 19,102 Lacaune sheep using 50 k single nucleotide polymorphism (SNP) phased genotypes pedigree data, we identified 11 deficient...
The collective economic and environmental interest of the whole dairy sheep sector is to reduce feed costs negative impact milk production on environment. Thus, this study focused characterization genetic selection potential efficiency in Lacaune breed. Estimates for ewes are limited, mainly due a lack individual intake measurements sheepfold or pasture. We estimated parameters two approximated (not entirely based data) traits (lactation conversion ratio (LFCR) residual energy (REI)) daily...
Abstract Background Genomic evaluation is usually based on a set of markers assumed to be linked with causal mutations. Selection and precise management major genes the remaining polygenic component might improved by including polymorphisms in models. In this study, various methods involving known mutation were used estimate prediction accuracy. The SOCS2 gene, which influences body growth, milk production somatic cell scores, proxy for mastitis, was studied as an example dairy sheep....
Abstract Background Recessive deleterious variants are known to segregate in livestock populations, as humans, and some may be lethal the homozygous state. Results We used phased 50 k single nucleotide polymorphism (SNP) genotypes pedigree data scan genome of 6845 Manech Tête Rousse dairy sheep search for deficiency haplotypes (DHH). Five deficient (MTRDHH1 5) were identified, with a ranging from 84 100%. These located on Ovis aries chromosome (OAR)1 (MTRDHH2 3), OAR10 (MTRDHH4), OAR13...
The identification of loci associated with resistance to mastitis or the causative mutations may be helpful in breeding programs for dairy sheep as it is cattle worldwide. Seven genomic regions that control milk somatic cell counts, an indirect indicator udder infection, have already been identified (Spanish Churra, French Lacaune and Italian Sardinian–Lacaune backcross populations). In this study, we used a 960 custom-designed ovine single nucleotide polymorphism (SNP) chip Manech Tête...
Purpose The purpose of this paper is to investigate the role instruments defined as artefacts, rules, models or norms, in articulation between knowing‐in‐practice and knowledge, learning processes. Design/methodology/approach focuses on a distributed, knowledge‐intensive instrumented activity at core any collective action: qualification. particular case breeding activities livestock sector has been studied, where practices animal qualification for have studied. Qualitative data stemming from...
Genetic selection has proven to be a successful strategy for the sustainable control of gastrointestinal parasitism in sheep. However, little is known on relationship between resistance parasites and production traits dairy breeds. In this study, we estimated heritabilities genetic correlations milk blond-faced Manech breed. The 951 rams from scheme was measured through fecal egg counts (FEC) at 30 days post-infection under experimental conditions. Six [milk yield (MY), fat (FY), protein...
Les travaux conduits en ovins laitiers dès 1993 dans des élevages atteints de tremblante ont permis connaître la fréquence allèles sensibles du gène PrP selon les races considérées, vérifier le risque accru pour ces génotypes, et tester faisabilité d’une sélection sur son efficacité troupeaux. Ils ainsi contribué à l’émergence l’outil génétique éradiquer atteints. Depuis 2002, programme d’éradication mis place France par Ministère l’Agriculture, est fondé génotypage : il vise court moyen...
La variabilité génétique est la marge de progression, le carburant sélection, et il apparaît d’autant plus important d’en réaliser un état des lieux que l’arrivée sélection génomique chez les ovins laitiers en France devrait s’accompagner d’une diminution l’intervalle génération augmentation du progrès génétique. Une analyse rétrospective gestion races ovines laitières françaises à partir informations généalogiques a été réalisée sur 40 dernières années. bien maîtrisée dans Lacaune (LL)...
Spanish Latxa and French Manech are dairy sheep breeds that split into Blond (Latxa Cara Rubia, LCR; Tête Rousse, MTR) Black Negra of Navarre, LCN; Noire, MTN) strains. Exchange genetic material (artificial insemination doses) is becoming more frequent across these breeds, within color, to boost both genomic precision using a larger reference population progress selection base. This exchange leads some rams having descendance countries. However, additional gains can only be achieved if the...
Some mutations (or 'major genes') have a desirable effect in heterozygous carriers but an undesirable homozygous carriers. When these affect trait of significant economic importance, their eradication, depending on and frequency, may be counterproductive. This is especially the case major genes affecting ovulation rate thus prolificacy meat sheep populations. To manage such situations, mating design based genotypes reproducers has to optimized. Both gene cost genotyping candidates at this...