Estimates of heritability within herd (h(WH)(2) ) that were generated with daughter-dam regression, daughter-sire regression, and REML were compared, and effects of adjusting lactation records for within-herd heritability on genetic evaluations were evaluated. Holstein records for milk, fat, and protein yields and somatic cell score (SCS) from the USDA national database represented herds in the...

A total of 138,869 lactation milk yields (305 d, milked twice daily, mature equivalent) from the first three parities of 68,063 New York Holstein cows were used to estimate variance components that were due to additive direct genetic effects, cow permanent environmental effects (cow within sire for sire model), sire by herd interaction effects, and cytoplasmic line effects. The original data we...

Climate change is rapidly altering the thermal environment in terrestrial and aquatic systems. Transgenerational plasticity (TGP) – which occurs when temperatures experienced by parental generation prior to fertilization of gametes results a offspring reaction norms may mitigate effects climate change. Although “maternal effects” have been widely studied, relatively little known about TGP verte...

One hundred sixteen spring-calving Polled Hereford x Angus cows were milked using milking machines after receiving 20 IU of oxytocin. Sires of the cows had been divergently selected on yearling weight (YW) and total maternal (MAT) EPD to form four groups: high YW, high MAT EPD; high YW, low MAT EPD; low YW, high MAT EPD; and low YW, low MAT EPD. Average milk production after 12-h calf separatio...

the aims of this research were to estimate of genetic parameters for pre-weaning traits and lamb survival in iran-black sheep. for this purpose 6344 records for birth weight (bw) and lamb survival (ls) and 5264 records for weaning weight (ww), average daily gain (adg) and kleiber ratio (kr) were available, which collected by abbasabad animal breeding and rearing station, over the period from 19...

Five alternative models were applied for analysis of dystocia and stillbirth in first and second parities. Models 1 and 2 were included only to estimate the parameters required for model 4, and models 3 and 5 are included only as comparisons to the model 4 estimates. Variance components were estimated by multi-trait REML, including cows with valid calving records for both parities. For the effe...

Quality measures of lamb longissimus dorsi were evaluated in 514 crossbred wether lambs to assess sire breed differences. Wethers were produced over 3 yr from single-sire matings of 22 Columbia, 22 U.S. Meat Animal Research Center (USMARC)-Composite (Composite), 21 Suffolk, and 17 Texel rams to adult Rambouillet ewes. Lambs were reared to weaning in an extensive western rangeland production sys...

The purpose of this study was to evaluate the effect of adjusting for heterogeneous variances across breed groups on prediction of breeding values (PBV) of selected sires and on breed of sire effects. Data on weights at birth (BWT), 200 d (WW), and 365 d (YW) of purebred and crossbred calves from matings of Angus (A), Hereford (H), Polled Hereford, Charolais, Shorthorn, Simmental, Limousin, Mai...

OBJECTIVE This study was conducted to estimate breed-specific variance components for total number born (TNB), number born alive (NBA) and mortality rate from birth through weaning including stillbirths (MORT) of three main swine breeds in Korea. In addition, the importance of including maternal genetic and service sire effects in estimation models was evaluated. METHODS Records of farrowing ...

The genetic model for fetal effect on production of the dam is described, and studies on genetic and economic implications are reviewed. The effect on production from the sire of the cowhas 1.58 to 3.02 times as much economic value as the effect from the sire of the fetus. The use of mate records in evaluating a sire in addit ion to daughter records could increase economic gain from selection b...