Calving complications have an incidence on the economic profitability of dairy herds. In the Walloon Region of Belgium, calving ease data recording is being done on voluntary basis since 2000. This allows now the implementation of a genetic evaluation of Holstein dairy cattle addressing the need of dairy breeders to select bulls in order to reduce frequency of calving problems. Calving ease sco...

In this paper, we demonstrate how simulation studies can be used to answer questions about identifiability and consequences of omitting effects from a model. The methodology is presented through a case study where identifiability of genetic and/or individual (environmental) maternal effects is explored. Our study system is a wild house sparrow (Passer domesticus) population with known pedigree....

Field records from the American Simmental Association were used to estimate genetic parameters for direct and maternal effects of traits associated with dystocia. Estimates of the additive genetic variances of direct and maternal effects and of the additive genetic covariances of direct and maternal effects were calculated by equating the sire variance component, maternal grandsire variance com...

combining ability, gene action, heritability and other genetic parameters in bread wheat under drought stress condition were evaluated using half diallel design. nine wheat cultivars and 36 derived f1 assessed in a randomized complete block design with three replications in shahid bahonar university of kerman research field in 2013. evaluated genotypes showed high diversity for all traits. gene...

Genetic evaluations in Brazil are performed within each animal breed; however, with the wide range of extant genetic groups in the country and the increased use of genetic crossing as a form of rapid meat production, more elaborate programs that can jointly evaluate animals of different genetic groups are needed. Genetic evaluation of a composite breed is difficult because of the variation in t...

a selection program is being implemented to improve meat production in makooei sheep. increasing litter size per ewe is the main objective, but possible repercussions on weight traits of lambs should be considered. the aim of this study was to estimate heritability along with genetic and phenotypic correlations between ewe's reproductive vs. weight traits in makooei ewes. data were comprised of...

Direct additive, dominance and genetic parameters for ultrasound scan traits of a multi-breed population involving European, British, Sanga and Brahman breed types were estimated. A generalized ridge regression technique was used to eliminate high associations among some of the genetic effects in the model. Clear breed type effects were observed for all scanned traits. European breeds had negat...