A backcross pedigree using dairy East Friesian rams and non-dairy Dorset ewes was established specifically to map quantitative trait loci (QTL) affecting milk production in sheep. Ninety nine microsatellite markers of an initial set of 120 were successfully genotyped and informative on 188 animals of this backcross pedigree. Test-day milk records on individual ewes were used to estimate several...

Phosphodiesterase9A (PDE9A) is a cyclic guanosine monophosphate (cGMP)-specific enzyme widely expressed among the tissues, which is important in activating cGMP-dependent signaling pathways. In our previous genome-wide association study, a single nucleotide polymorphism (SNP) (BTA-55340-no-rs(b)) located in the intron 14 of PDE9A, was found to be significantly associated with protein yield. In ...

Leptin and leptin receptor genes are considered as production traits markers in dairy or beef cattle. The aim of this study was to verify the associations of polymorphisms in bovine LEP and LEPR genes with production and reproduction traits in Slovak Spotted and Pinzgau cows. Long-life production was evaluated: milk, protein, and fat yield and reproduction traits: age at first calving, calving ...

In Australia, dairy cattle account for ~12% of the nation’s agricultural greenhouse-gas (GHG) emissions. Genetic selection has had a positive impact, reducingGHGemissions fromdairy systemsmainly due to increased production per cow,which has led to (1) requiring fewer cows to produce the same amount ofmilk and (2) lowering emissions per unit of milk produced (emission intensity). The objective o...

Preweaning and weaning records on 457 calves and weights and milk production of their dams were used to evaluate breed of dam effects, breed of sire effects, and individual heterosis effects. Hereford and Tarentaise dams were mated to Hereford and Tarentaise sires and calves were born from 1987 to 1991. Calf traits were birth weight, proportion calving difficulty, weaning weight, weaning height...

the aim of this study was using bayesian approach via gibbs sampling (gs) for estimating genetic parameters of production, reproduction and health traits in iranian holstein cows. data consisted of 320666 first- lactation records of holstein cows from 7696 sires and 260302 dams collected by the animal breeding center of iran from year 1991 to 2010. (co) variance components were estimated using ...

Breed additive and non-additive effects, and genetic parameters of lactation milk yield (LYD), 305-day milk yield (305YD), lactation length (LL), milk yield per day of lactation (DM) and lifetime milk yield (LTYD) were estimated in Ethiopian Boran cattle and their crosses with Holstein in central Ethiopia. The data analyzed included 2360 lactation records spread over 15 years. Ethiopian Boran c...

In Australia, dairy cattle account for ~12% of the nation’s agricultural greenhouse-gas (GHG) emissions. Genetic selection has had a positive impact, reducingGHGemissions fromdairy systemsmainly due to increased production per cow,which has led to (1) requiring fewer cows to produce the same amount ofmilk and (2) lowering emissions per unit of milk produced (emission intensity). The objective o...

Genetic and phenotypic parameters for body condition score (BCS), days to first service (DFS), non-return rate (NRR), somatic cell score (SCS), and 305-day milk, fat and protein yields were estimated, using 38930 multiple lactation records of cows across 1830 herds. The cows were daughters of 243 different sires. Singleand multi-trait repeatability animal models were used to estimate parameters...