ABSTRACT Compared with cow fertility, genetic analyses of bull fertility are limited and based on relatively few animals. The aim the present study was to estimate parameters for semen characteristics Norwegian Red bulls at artificial insemination (AI) center (Geno AI station, Stange, Norway) correlations between some these traits andrology measured performance test station. data from ...

Assumptions of normality in most animal breeding applications may make inferences vulnerable to the presence of outliers. Heavy-tail densities are viable alternatives to normal distributions and provide robustness against unusual or outlying observations when used to model the densities of residual effects. Our objective is to compare estimates of genetic parameters by fitting multivariate norm...

embryo transfer (et) in holstein dairy cattle became an important commercial enterprise after the introduction of non-surgical recovery technique. embryo transfer could increase the reproductive rate of genetically superior cows. the objectives of the present study were to evaluate the use of et in iranian holstein dairy cattle to increase selection intensity on the dam side, economically; esti...

This study examined the heritability of brain grey matter structures in a subsample of older adult twins (93 MZ and 68 DZ twin pairs; mean age 70 years) from the Older Australian Twins Study. The heritability estimates of subcortical regions ranged from 0.41 (amygdala) to 0.73 (hippocampus), and of cortical regions, from 0.55 (parietal lobe) to 0.78 (frontal lobe). Corresponding structures in t...

In this study test-day records of milk (kg), fat (g), and protein (g) yields, somatic cell score (SCS, cells/ML) collected by Animal Breeding Center of Iran during 2007 and 2009 were used to estimate genetic parameters using random regression model. Models with different order of Legendre polynomials were compared using Bayesian information criterion (BIC).For milk, fat yield and SCS genetic an...

the purpose of this study was to describe the association between grain yield and its components. the experiment was conducted in a randomized complete block design with three replicatsions. results of analysis showed that similar trends were observed for genotypic and phenotypic correlations and in most cases, the value for genetic correlation was greater than phenotypic value. 100-seed weight...

The decline of fertility in the UK dairy herd and the unfavorable genetic correlation (r(a)) between fertility and milk yield has necessitated the broadening of breeding goals to include fertility. The coefficient of genetic variation present in fertility is of similar magnitude to that present in production traits; however, traditional measurements of fertility (such as calving interval, days ...

The objective of this study was to estimate genetic correlations between calving difficulty score and carcass traits in Charolais and Hereford cattle, treating first and later parity calvings as different traits. Genetic correlations between birth weight and carcass traits were also estimated. Field data on 59,182 Charolais and 27,051 Hereford calvings, and carcass traits of 5,260 Charolais and...