Random regression models were used to estimate the types and orders of random effects of (co)variance functions in the description of the growth trajectory of the Simbrasil cattle breed. Records for 7049 animals totaling 18,677 individual weighings were submitted to 15 models from the third to the fifth order including as fixed effects sex, contemporary group, feeding regimen, and type of repro...

the mode of agronomic traits inheritance was investigated in safflower (carthamus tinctorius l.) in drought stress as a new report. five generation including p1, p2, f1, f2 and f3 that derived from the cross of il.111 (drought sensitive) ×mex.22-191 (drought tolerance) were used in a randomized complete block design with two replications. generation mean analysis was used to estimate genetic pa...

Dominance and additive x additive genetic variances were estimated for birth and weaning traits of calves from three synthetic lines of beef cattle differing in mature size. Data consisted of 3,992 and 2,877 records from lines of small-, medium-, and large-framed calves in each of two research herds located at Rhodes and McNay, IA, respectively. Variance components were estimated separately by ...

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...

autoselection is a kind of natural selection, that occurs in reproductive traits by inequality of offspring generation and therefore by virtue of the nature of its genes transmission to next generations. in this study, the effects of autoselection on heritability and selection response in reproductive traits by using univariate stochastic computer simulation in artificial selected and unselecte...