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...

Traditional methods of variance component estimation for traits under maternal influence consist of partitioning the variance into direct additive genetic, maternal additive genetic, permanent maternal environmental, and error variance components. This partitioning is based on the assumption that each calf is nurtured and fed exclusively by its own dam. However, under extensive pastoral systems...

BACKGROUND Autism spectrum disorder (ASD) has both genetic and environmental origins, including potentially maternal effects. Maternal effects describe the association of one or more maternal phenotypes with liability to ASD in progeny that are independent of maternally transmitted risk alleles. While maternal effects could play an important role, consistent with association to maternal traits ...

The objective of this study was to examine the feasibility of using random regression-spline (RR-spline) models for fitting growth traits in a multibreed beef cattle population. To meet the objective, the results from the RR-spline model were compared with the widely used multitrait (MT) model when both were fit to a data set (1.8 million records and 1.1 million animals) provided by the America...

The purpose of this study was to compare estimates of genetic parameters for sequential growth of beef cattle using two models and two data sets. Growth curves of Nellore cattle were analyzed using body weights measured at ages 1 (birth weight) to 733 d. Two data samples were created, one with 71,867 records sampled from all herds (MISS), and the other with 74,601 records sampled from herds wit...

This study aimed to elucidate the maternal and paternal genetic effects of physiological quality hybrid seed corn over time, as well contribution heterosis for this trait. The seeds single hybrids, reciprocals parents were obtained by manual crosses in a complete diallel cross scheme. analyses germination accelerated aging performed data analyzed with Tukey test Griffing method. quadratic compo...

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...

Estimates of covariances and sire expected progeny differences of additive and nonadditive direct and maternal genetic effects for birth and weaning weights were obtained using records from 1,581 straightbred and crossbred calves from the Angus-Brahman multibreed herd at the University of Florida. Covariances were estimated by Restricted Maximum Likelihood, using a Generalized Expectation-Maxim...

this study was conducted to investigate direct and maternal effects on some economic traits in north iranian native fowls. traits considered were body weight at 1 day of age (bw1), body weight at 8 weeks of age (bw8), body weight at 12 weeks of age (bw12), egg number (en) during the first 12 weeks of laying period, egg weight at 1st day of laying (ew1), mean egg weight at 28th, 30th and 32nd we...