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Book Estimation of Breed specific Heterosis Effects for Birth Weaning and Yearling Weight in Cattle

Download or read book Estimation of Breed specific Heterosis Effects for Birth Weaning and Yearling Weight in Cattle written by Lauren N. Schiermiester and published by . This book was released on 2014 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt: Genetic selection decisions are important components of improved beef production efficiency. Exploiting heterosis and breed complementarity can improve economically relevant traits and system efficiency. The objective of the current study was to estimate breed-specific heterosis for the seven largest beef breeds (according to registrations) for birth, weaning and yearling weight. Birth, weaning and yearling weights were recorded for steers, heifers and bulls (n= 6,834) from Cycle VII and advanced generations of the Germ Plasm Evaluation project of the U.S. Meat Animal Research Center. Breeds represented in these data included: Angus, Hereford, Red Angus, Charolais, Gelbvieh, Simmental, Limousin and composite MARC III. Model 1 estimated heterosis assuming different levels within and between biological types (British or Continental). Model 2 estimated breed-specific heterosis (a different level of heterosis for each pair of breeds). Heterosis was assumed proportional to expected breed heterozygosity. Direct heritability estimates (SE) for birth, weaning and yearling weight for Model 1 were 0.42 (0.04), 0.22 (0.03) and 0.39 (0.05), respectively. The direct heritability estimates (SE) for Model 2 were the same as Model 1 except yearling weight heritability was 0.38 (0.05). There were differences in levels of heterosis based on biological type (Model 1) and breed (Model 2). Model 1 results for the British x British (BxB), British x Continental (BxC) and Continental x Continental (CxC) heterosis estimates for birth weight were 0.47 (0.37), 0.75 (0.32) and 0.73 (0.54) kg, respectively. The BxB, BxC and CxC heterosis estimates for weaning weight were 6.43 (1.80), 8.65 (1.54) and 5.86 (2.57) kg, respectively. Yearling weight estimates for BxB, BxC and CxC heterosis were 17.59(3.06), 13.88 (2.63) and 9.12 (4.34) kg, respectively. Breed differences exist and can lead to varying levels of heterosis. Specific estimates of heterosis could be useful when selecting breeds for a crossbreeding system and developing composite populations for various production environments and could be useful in multibreed evaluations as heterosis and breed differences are needed to accurately adjust records to produce genetic predictions..

Book Estimation of Direct and Maternal Additive and Heterotic Effects for Preweaning Growth Traits in Cattle Breeds Represented in the Southern Region

Download or read book Estimation of Direct and Maternal Additive and Heterotic Effects for Preweaning Growth Traits in Cattle Breeds Represented in the Southern Region written by Wayne Edward Wyatt and published by . This book was released on 1986 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Identifying Breed Effects for Cow Mature Weight

Download or read book Identifying Breed Effects for Cow Mature Weight written by Madeline J. Zimmermann and published by . This book was released on 2018 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mature weight (MWT) in beef cattle has increased over the past 30 yr. In general, larger cows are costlier to maintain than smaller cows, and their profitability depends on their production environment. A wide range of beef production environments exist in the United States. There are also a variety of beef cattle breeds that can be chosen and mated to create a type of cow which will be optimally suited to excel in a given environment. However, there remains a need for tools allowing effective comparison among breeds to facilitate such decision making. Unfortunately, estimated progeny differences (EPD) for MWT are not currently available in most breeds. However, understanding growth to maturity and estimating breed effects for MWT can facilitate more informed breeding systems that rely on MWT as a proxy for cow maintenance costs. First, growth from weaning to maturity was studied using weight data of crossbred cows from the Germplasm Evaluation Program (GPE) at the U.S. Meat Animal Research Center in Clay Center, Nebraska. Brody, spline, and quadratic functions were fitted. For the spline and quadratic functions, MWT was estimated at 6 yr of age from fitted parameters. The spline function seemed to fit these data best, but the Brody function was more reliable for estimating MWT. Its estimated values were consistent even when weights taken at younger ages were used to estimate MWT, with few extreme MWT estimates generated. Second, MWT estimates from the aforementioned functions were analyzed by fitting an animal model including fixed effects of breed fractions and birth year-season contemporary group, and linear covariates of direct and maternal heterosis. Resulting breed covariate solutions were divided by 2 to obtain breed of sire solutions. Breed of sire solutions were adjusted for sire sampling to determine the breed effect for MWT in each of 18 commonly-used beef cattle breeds represented in the GPE population. Since MWT EPD were not available for most breeds, yearling weight EPD was used as a proxy. The breed effects calculated can help seedstock producers identify appropriate breeds that will suit their operation's unique environments and breeding goals.

Book Beef Cattle Breeding

Download or read book Beef Cattle Breeding written by United States Agricultural Research Service and published by . This book was released on 1977 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Beef Cattle Breeding

Download or read book Beef Cattle Breeding written by Larry V. Cundiff and published by . This book was released on 1977 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Heterosis and Heterosis Retention for Reproductive and Maternal Traits in Brahman X Hereford Crossbred Cows

Download or read book Heterosis and Heterosis Retention for Reproductive and Maternal Traits in Brahman X Hereford Crossbred Cows written by Lydia Boenig and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Book Agriculture Information Bulletin

Download or read book Agriculture Information Bulletin written by and published by . This book was released on 1949 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Pegmatites in West Greenland

Download or read book Pegmatites in West Greenland written by Hans Ramberg and published by . This book was released on 1956 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Heterosis and Heterosis Retention for Reproductive and Maternal Traits in Nellore Angus Crossbred Cows

Download or read book Heterosis and Heterosis Retention for Reproductive and Maternal Traits in Nellore Angus Crossbred Cows written by Mohammad Diya Talal Hamed Obeidat and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Calving rate, weaning rate, birth weight, weaning weight, and ADG from 1997 to 2011 were investigated in Angus, Nellore, F_(1) Nellore-Angus, first generation 3/8 Nellore 5/8 Angus produced as following: (1/2 Nellore 1/2 Angus sires and 3/4 Angus 1/4 Nellore dams, 3/4 Angus 1/4 Nellore sires and 1/2 Angus 1/2 Nellore dams, and 3/4 Nellore 1/4 Angus sires and Angus dams), and second generation 3/8 Nellore 5/8 Angus cows. The objectives were to estimate heterosis in Nellore-Angus crosses for cow reproductive traits and maternal effects on traits of their calves. The F_(1) cows expressed 0.20 ± 0.02 heterosis for calving rate, while both first and second generation 3/8 Nellore 5/8 Angus expressed 0.13 ± 0.02. the first generation 3/8 Nellore 5/8 Angus produced out of 3/4 Angus 1/4 Nellore sires and 1/2 Nellore 1/2 Angus dams expressed 0.14 ± 0.03 heterosis for calving rate. The F1 Nellore-Angus expressed 0.23 ± 0.03 heterosis for weaning rate and the 3/8 Nellore 5/8 Angus produced out of 3/4 Angus 1/4 Nellore sires × 1/2 Nellore 1/2 Angus dams and the second generation 3/8 Nellore 5/8 Angus expressed 0.14 ± 0.07 and 0.15 ± 0.05, respectively. No heterosis was expressed for birth weight in any breedtype group. Multiple attempts to analyze weaning weight and ADG and estimate heterosis resulted in excessive adjustments to least squares means. Young and oldest cows weaned lighter calves than others. F_(1) cows weaned heavier calves at most ages. Nellore-sired F_(1) calves were heavier at weaning than the reciprocal cross. Calves out of cows of intermediate ages had larger preweaning ADG than calves born to 2- and 3-yr-old and to aged cows. Generally, calves out of F_(1) Nellore-Angus cows had larger ADG than those out of cows of other breedtypes. Nellore-sired F_(1) heifers had lower ADG than Angus-sired F_(1) heifers. In general, bull calves had larger ADG than heifers. Non-F_(1) crossbred cows expressed slightly larger heterosis than what would be expected by the dominance model. Heterosis expressed by second generation 3/8 Nellore 5/8 Angus for calving and weaning rate did not appear to differ from the first generation. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/151235

Book Guidelines for Uniform Beef Improvement Programs

Download or read book Guidelines for Uniform Beef Improvement Programs written by Dixon D. Hubbard and published by . This book was released on 1981 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Effects of Sire Misidentification on Estimates of Genetic Parameters for Birth Weight and Weaning Weight in Hereford Cattle

Download or read book Effects of Sire Misidentification on Estimates of Genetic Parameters for Birth Weight and Weaning Weight in Hereford Cattle written by Sandra L. Senneke and published by . This book was released on 2002 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Estimation of Direct and Maternal Additive and Heterotic Effects for Measures of Size Growth and Maturing Pattern in Cattle

Download or read book Estimation of Direct and Maternal Additive and Heterotic Effects for Measures of Size Growth and Maturing Pattern in Cattle written by Mohamed Ariff Omar and published by . This book was released on 1984 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt: