introduction small ruminants, especially native breed types, play an important role in livelihoods of a considerable part of human population in the tropics from socio-economic aspects. therefore, integrated attempt in terms of management and genetic improvement to enhance production is of crucial importance. knowledge of genetic variation and co-variation among traits is required for both the ...

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...

Pedigree yearling records from 1021 local Tuli calves born at Matopos Research Station were analyzed for non genetic factors, genetic parame ers and trends on the yearling weight. It was found that s re year of b rth, sex of calf age of dam had s gn f cant effect (p < 0.01) on a growth trait. The nconsistency o literature estimates indicated the importance o est mation o environmental factors t...

Genetic parameters of mature weight are needed for effective selection and genetic evaluation. Data for estimating these parameters were collected from 1963 to 1985 and consisted of 32,018 mature weight records of 4,175 Hereford cows that were in one control and three selection lines that had been selected for weaning weight, for yearling weight, or for an index combining yearling weight and mu...

the objective of this study was to estimate genetic parameters and to investigate the type of gene action in controlling androgenesis in wheat. two wheat cultivars of grebe and houtman were reciprocally crossed with two synthetic genotypes of do1 and pol and then a complete set of the parents, f1, reciprocal f1 (rf1), f2 and back-cross generations (bc1 and bc2) of each cross were used for anthe...

Estimates of genetic parameters resulting from various analytical models for birth weight (BWT, n = 4,155), 205-d weight (WWT, n = 3,884), and 365-d weight (YWT, n = 3,476) were compared. Data consisted of records for Line 1 Hereford cattle selected for postweaning growth from 1934 to 1989 at ARS-USDA, Miles City, MT. Twelve models were compared. Model 1 included fixed effects of year, sex, age...

Genetic parameters for nuclear and cytoplasmic genetic effects were estimated from preweaning growth data collected on three synthetic lines of beef cattle differing in mature size. Lines of small-, medium-, and large-framed calves were represented in each of two research herds (Rhodes and McNay). Variance components were estimated separately by herd and size line for birth weight and 205-d wei...