Objective: Estimation of genetic parameters for Kleiber ratio (KR) and genetic trends for pre-weaning weights of Arabi sheep has not been previously conducted.Methods: Data and pedigree information were collected at the Khuzestan Ramin Agricultural and Natural Resources University, Animal Science Research Station, located in southwest Iran, from 2001 to 2008. (Co)variance components and corresp...

Estimates of covariance components were obtained for milk production of beef cows, measured by the weigh-suckle-weigh method, and weaning weight and preweaning growth of their calves for a herd of Polled Herefords and a herd of a multibreed synthetics, so-called Wokalups. Analyses were carried out by restricted maximum likelihood fitting an animal model incorporating both direct and maternal ge...

introduction: genetic resources in any country are valuable materials which needed to be conserved for a sustainable agriculture. an animal phenotype is generally affected by genetic and environmental factors. to increase mean performance in a population under consideration not only environmental conditions, but also genetic potential of the animals should be improved. although, environmental i...

A total of 11,815 weight records from 23,94 Japanese Black calves was used to estimate direct, maternal, direct permanent environmental, and maternal permanent environmental effects on growth from birth to 356 d of age. The data were collected from a herd of Japanese Black cattle in Shiroshi city, Miyagi prefecture, Japan. A random regression model, including parity of dam and year-season of ca...

a total of 2000 records of egg quality of 746 birds and body weight data from 17th generation of fars native fowl breeding station were used to estimate the genetic parameters of egg quality and body weight traits. six univariate animal models with different random effects were fitted for each trait. a model with direct additive genetic and maternal permanent environmental effects was the most ...