Henderson described a method to reduce the number of mixed-model equations when estimating additive and nonadditive genetic variances or predicting additive and nonadditive genetic merits. The extension to a maternal effects model is straight-forward. When maternal genetic effects are strictly additive, an algebraic identity was found that reduces by a factor of two the order of a matrix that m...

breeding programs strategies depends on genetical mechanism of selection traits. in the present research, generation mean analysis with joint scaling test was performed to determine the gene action. f1, f2 and f3 generations, derived from roushan and kavir cross along with their parents were sown in a partial lattice design with two replications under stress condition at the research field of s...

in this study records of 15723, 12108 and 5236 zel sheep for birth weight (bw), weaning weight (ww) and 6-month weight (6mw) traits were used. data has been collected by the jahad-e-keshavarzi organization of province of mazandaran during 1994-2009. the heritability of direct and maternal of growth traits was estimated using the univariate analysis with restricted maximum likelihood (reml). in ...

Studying genetic parameters and genetic changes in Santa Ines sheep is important, because it is the commonest breed in Brazil. This study obtained genetic data from 37,735 pedigree records of lambs over 12 years (2003-2014) from 33 flocks in 10 Brazilian States; 11,851 records of performance were available. (Co)variance components, genetic parameters and breeding values estimates were obtained ...

Heritabilities of and genetic correlations between additive direct and maternal genetic effects for calf market weight, and additive direct genetic effects for carcass traits, were estimated for Japanese Black cattle by REML procedures under 2-trait animal models. Data were collected from calf and carcass markets in Hyogo and Tottori prefectures and analyzed separately by prefecture. Calf marke...

to study general and specific combining ability of some rice varieties for grain physical properties and milling quality, a diallel design with five parents (hashemi, vandana, kadous, shahpasand and ir36) was used. parents and their f1 progenies (25 genotypes) were grown in a randomized complete blocks design with three replications in the research field of rice research institute of iran (rrii...

the data set used in this study contained 8793 records of lamb's longevity (days) from 320 sires and 2349 dams collected during 1989 to 2014, from the lori-bakhtiari flock at shooli station in shahrekord, iran. genetic parameters (partitioned into autosomal, sex-linked and maternal) and breeding values of cumulative lamb's longevity from birth up to yearling age (at 1, 2, 3, 6, 9 and ...

Covariance components and genetic parameters of weekly live body weight from hatching to six weeks of age and age of sexual maturation were estimated in a laying type Japanese quail line. The univariate and bivariate animal model analysis included hatching group and sex as fixed effects. Each trait was analysed with animal as random effect to fit the additive direct effect. Additional random ef...

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...