Author: Marc Stephen TaylorPublisher:
ISBN:
Category : Heterosis
Languages : en
Pages : 110
Book Description
Abstract.
Heterosis and Productivity Estimates for Preweaning Traits in Brahman Crossbred Beef Cattle
Author: Marc Stephen TaylorPublisher:
ISBN:
Category : Heterosis
Languages : en
Pages : 110
Book Description
Abstract.
Estimation of Maternal Heterosis of Preweaning Traits and Prediction of Rotational Crossbreeding Performance in Beef Cattle
Author: Richard Peterson McDonaldPublisher:
ISBN:
Category :
Languages : en
Pages : 108
Book Description
Estimation of Direct and Maternal Additive and Heterotic Effects for Preweaning Growth Traits in Cattle Breeds Represented in the Southern Region
Author: Wayne Edward WyattPublisher:
ISBN:
Category : Cattle
Languages : en
Pages : 40
Book Description
Estimation of Maternal Heterosis in Pre-weaning Traits and Prediction of Rotational Crossbreeding Performance in Beef Cattle
Author: Richard Peterson McDonaldPublisher:
ISBN:
Category : Beef cattle
Languages : en
Pages : 108
Book Description
Heterotic and Environmental Effects in Rotational Crossbreeding of Beef Cattle
Author: Cristo Nazaré Barbosa Do NascimentoPublisher:
ISBN:
Category :
Languages : en
Pages : 168
Book Description
To determine the productivity of Brahman, Hereford, and crossbred cattle measured by pregnancy, calving and weaning percentages of cows and weaning weight of calves. To estimate the yield of milk produced by crossbred, Brahman and Hereford cows. To determine the relationship of yield of milk produced by Brahman, Hereford and crossbred cows to growth rates and weaning weights of their calves. To evaluate the effect of sex, year and month of birth as well as breed or cross of calf, and age of dam on calf weaning weight.
Heterosis and Heterosis Retention for Reproductive and Maternal Traits in Brahman X Hereford Crossbred Cows
Author: Lydia BoenigPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Calf crop born, calf crop weaned, calf birth weight, calf weaning weight, and cow weight at weaning were evaluated from 1996 to 2009 in Brahman (B) and Hereford (H) straightbred and crossbred cows (n = 1,515). The objective of these analyses was to estimate heterosis for F1 and F2 females for these reproductive and maternal traits. Breed groups included B, H, F1 Hereford-sired (HB) and Brahman-sired (BH) cows (n = 114 purebreds, 55 F1, 52 F2). Second generation breed groups included cows sired by HB and out of HB dams (F2HB) and BH dams (HBxBH); and cows sired by BH and out of HB dams (BHxHB) and BH dams (F2BH). Least squares means were calculated for calf crop born, calf crop weaned, and calf birth and weaning weights, using numerous different models, where the trait was the dependent variable. Previous research and these preliminary analyses showed that the effects of year and cow age are real as is their interaction each other and with breed type. In each attempted model designed to remove these effects, different breed groups received excessive adjustments, rendering the resultant heterosis estimates inappropriate. To more clearly assess differences, presentation and visual evaluation of unadjusted means were conducted. The model for mature cow weight (cows at 6 years of age) included breed group as fixed effects and cow within breed group and year as random effects. F2 cows appeared to retain approximately 39% of F1 heterosis for calf crop born and approximately 50% for calf crop weaned. HB x BH cows delivered the lightest calves at 33.9 (4.74) kg and F2BH had the heaviest calves at birth at 36.6 (5.37) kg. BH cows weaned the heaviest calves at 240.9 (38.1) kg and F2BH cows weaned the lightest calves at 208.4 (31.9) kg. Sire breed of calf and age of cow appear to be important factors regarding weight traits. Retained heterosis for cow weight at weaning was higher than expected at 73%. Sire breed group differences (HB vs. BH) for these traits in F2 cows may merit further investigation.
Livestock Productivity and Trypanotolerance
Author: International Livestock Centre for AfricaPublisher: ILRI (aka ILCA and ILRAD)
ISBN:
Category :
Languages : en
Pages : 180
Book Description
Journal of Animal Science
Author: Abstracts - American Society of Animal Science
Author: Publisher:
ISBN:
Category : Animal culture
Languages : en
Pages : 660
Book Description
Consists of abstracts of papers presented at the national and sectional meetings of the American Society of Animal Science.
Author: