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Full-Text Articles in Life Sciences
Genetic Parameters, Heterosis, And Breed Effects For Body Condition Score And Mature Cow Weight In Beef Cattle, André Mauric F. Ribeiro, Leticia P. Sanglard, Warren M. Snelling, R. Mark Thallman, Larry A. Kuehn, Matthew L. Spangler
Genetic Parameters, Heterosis, And Breed Effects For Body Condition Score And Mature Cow Weight In Beef Cattle, André Mauric F. Ribeiro, Leticia P. Sanglard, Warren M. Snelling, R. Mark Thallman, Larry A. Kuehn, Matthew L. Spangler
Department of Animal Science: Faculty Publications
Understanding the genetic relationship between mature cow weight (MWT) and body condition score (BCS) is useful to implement selection programs focused on cow efficiency. The objectives of this study were to estimate genetic parameters, heterosis, and breed effects for MWT and BCS. In total, 25,035 and 24,522 overlapping records were available for MWT and BCS on 6,138 and 6,131 cows, respectively, from the Germplasm Evaluation program, a crossbred beef population at the U.S. Meat Animal Research Center. Pedigree was available for 48,013 individuals. Univariate animal models were used to estimate heritabilities for each trait by parity. …
Model Definition For Genetic Evaluation Of Purebred And Crossbred Lambs Including Heterosis, Napoleón Vargas Jurado, David R. Notter, Joshua B. Taylor, Daniel J. Brown, Michelle R. Mousel, Ronald M. Lewis
Model Definition For Genetic Evaluation Of Purebred And Crossbred Lambs Including Heterosis, Napoleón Vargas Jurado, David R. Notter, Joshua B. Taylor, Daniel J. Brown, Michelle R. Mousel, Ronald M. Lewis
Department of Animal Science: Faculty Publications
Crossbreeding is a common practice among commercial sheep producers to improve animal performance. However, genetic evaluation of U.S. sheep is performed within breed type (terminal sire, semi-prolific, and western range). While incorporating crossbred records may improve assessment of purebreds, it requires accounting for heterotic and breed effects in the evaluation. The objectives of this study were to: 1) describe the development of a paternal composite (PC) line, 2) determine the effect of direct and maternal heterosis on growth traits of crossbred lambs, 3) estimate (co)variance components for direct and maternal additive, and uncorrelated maternal environmental, effects, and 4) provide an …
Breed And Heterotic Effects For Mature Weight In Beef Cattle, Madeline J. Zimmermann, Larry A. Kuehn, Matthew L. Spangler, R. M. Thallman, Warren M. Snelling, Ronald M. Lewis
Breed And Heterotic Effects For Mature Weight In Beef Cattle, Madeline J. Zimmermann, Larry A. Kuehn, Matthew L. Spangler, R. M. Thallman, Warren M. Snelling, Ronald M. Lewis
Department of Animal Science: Faculty Publications
Cow mature weight (MWT) is heritable and affects the costs and efficiency of a breeding operation. Cow weight is also influenced by the environment, and the relationship between the size and profitability of a cow varies depending on production system. Producers, therefore, need tools to incorporate MWT in their selection of cattle breeds and herd replacements. The objective of this study was to estimate breed and heterotic effects for MWT using weight-age data on crossbred cows. Cow's MWT at 6 yr was predicted from the estimated parameter values-asymptotic weight and maturation constant (k)-from the fit of the Brody function to …
Estimation Of Breed-Specific Heterosis Effects For Birth, Weaning, And Yearling Weight In Cattle, Lauren N. Schiermiester, R. M. Thallman, Larry Kuehn, Stephen D. Kachman, Matthew L. Spangler
Estimation Of Breed-Specific Heterosis Effects For Birth, Weaning, And Yearling Weight In Cattle, Lauren N. Schiermiester, R. M. Thallman, Larry Kuehn, Stephen D. Kachman, Matthew L. Spangler
Department of Animal Science: Faculty Publications
Heterosis, assumed proportional to expected breed heterozygosity, was calculated for 6834 individuals with birth, weaning and yearling weight records from Cycle VII and advanced generations of the U.S. Meat Animal Research Center (USMARC) Germplasm Evaluation (GPE) project. Breeds represented in these data included: Angus, Hereford, Red Angus, Charolais, Gelbvieh, Simmental, Limousin and Composite MARC III. Heterosis was further estimated by proportions of British × British (B × B), British × Continental (B × C) and Continental × Continental (C × C) crosses and by breed-specific combinations. Model 1 fitted fixed covariates for heterosis within biological types while Model 2 fitted …
Effects Of Age, Weight, And Fat Slaughter End Points On Estimates Of Breed And Retained Heterosis Effects For Carcass Traits, A. Ríos-Utrera, L. V. Cundiff, K. E. Gregory, R. M. Koch, M. E. Dikeman, M. Koohmaraie, L. Dale Van Vleck
Effects Of Age, Weight, And Fat Slaughter End Points On Estimates Of Breed And Retained Heterosis Effects For Carcass Traits, A. Ríos-Utrera, L. V. Cundiff, K. E. Gregory, R. M. Koch, M. E. Dikeman, M. Koohmaraie, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
The influence of different levels of adjusted fat thickness (AFT) and HCW slaughter end points (covariates) on estimates of breed and retained heterosis effects was studied for 14 carcass traits from serially slaughtered purebred and composite steers from the US Meat Animal Research Center (MARC). Contrasts among breed solutions were estimated at 0.7, 1.1, and 1.5 cm of AFT, and at 295.1, 340.5, and 385.9 kg of HCW. For constant slaughter age, contrasts were adjusted to the overall mean (432.5 d). Breed effects for Red Poll, Hereford, Limousin, Braunvieh, Pinzgauer, Gelbvieh, Simmental, Charolais, MARC I, MARC II, and MARC III …
Effects Of Age, Weight, And Fat Slaughter End Points On Estimates Of Breed And Retained Heterosis Effects For Carcass Traits, A. Ríos-Utrera, L. V. Cundiff, K. E. Gregory, R. M. Koch, M. E. Dikeman, M. Koohmaraie, L. Dale Van Vleck
Effects Of Age, Weight, And Fat Slaughter End Points On Estimates Of Breed And Retained Heterosis Effects For Carcass Traits, A. Ríos-Utrera, L. V. Cundiff, K. E. Gregory, R. M. Koch, M. E. Dikeman, M. Koohmaraie, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
The influence of different levels of adjusted fat thickness (AFT) and HCW slaughter end points (covariates) on estimates of breed and retained heterosis effects was studied for 14 carcass traits from serially slaughtered purebred and composite steers from the US Meat Animal Research Center (MARC). Contrasts among breed solutions were estimated at 0.7, 1.1, and 1.5 cm of AFT, and at 295.1, 340.5, and 385.9 kg of HCW. For constant slaughter age, contrasts were adjusted to the overall mean (432.5 d). Breed effects for Red Poll, Hereford, Limousin, Braunvieh, Pinzgauer, Gelbvieh, Simmental, Charolais, MARC I, MARC II, and MARC III …
Effects Of Inbreeding And Heterozygosity On Preweaning Traits In A Closed Population Of Herefords Under Selection, L. Dale Van Vleck, M. D. Macneil
Effects Of Inbreeding And Heterozygosity On Preweaning Traits In A Closed Population Of Herefords Under Selection, L. Dale Van Vleck, M. D. Macneil
Department of Animal Science: Faculty Publications
Records of five inbred lines at the Livestock and Range Research Laboratory were used to evaluate effects of inbreeding and heterozygosity on preweaning traits. Members of each line were descendants of a single founder Hereford bull. A total of 8,065 records of birth weight and 7,380 records of preweaning daily gain and weaning weight were analyzed by derivative-free REML using a model that included fixed effects of sex, combination of year and month of birth and parity of dam, with covariates for direct and maternal genetic fractions of inheritance from the genetic groups, inbreeding, and heterozygosity fractions. Heterozygosity fractions were …
Changes In Ovulation Rate, Uterine Capacity, Uterine Dimensions, And Parity Effects With Selection For Litter Size In Swine, Luis L. T. Gama, R. K. Johnson
Changes In Ovulation Rate, Uterine Capacity, Uterine Dimensions, And Parity Effects With Selection For Litter Size In Swine, Luis L. T. Gama, R. K. Johnson
Department of Animal Science: Faculty Publications
This study was conducted with random samples of pigs of a line (LS) selected for eight generations for litter size and a randomly selected control line (RS) in the Nebraska Gene Pool population and of crosses of these lines with a Large White- Landrace composite line (I) that was selected for an index of ovulation rate and embryonic survival to 50 d of gestation. Two experiments were done to obtain information on ovulation rate, uterine dimensions, and uterine capacity. In Exp. 1, 103 gilts were slaughtered 9 to 16 d after their second estrus to obtain reproductive tracts for evaluation …
Individual Heterosis And Breed Effects For Postweaning Performance And Carcass Traits In Four Breeds Of Swine, D. G. Mclaren, D. S. Buchanan, R. K. Johnson
Individual Heterosis And Breed Effects For Postweaning Performance And Carcass Traits In Four Breeds Of Swine, D. G. Mclaren, D. S. Buchanan, R. K. Johnson
Department of Animal Science: Faculty Publications
Individual heterosis and direct and maternal breed effects for postweaning average daily gain (ADG), off-test age (AGE) and probed backfat thickness (BF) were estimated from data on 1,664 pigs produced in a complete diallel mating system involving the Duroc, Yorkshire, Landrace and Spotted breeds. The same genetic parameters were estimated for various carcass traits by analyses of data collected on 269 barrow carcasses. Significant breed x environment (i.e., year-season farrowed, parity and sex) interactions were found for ADG, AGE and BF. Specific heterosis estimates for ADG and AGE were all highly significant and reasonably consistent among crosses. Overall heterosis for …
Simulation Of Heterosis Effects On Costs Of Pork Production, G. L. Bennett, M. W. Tess, G. E. Dickerson, R. K. Johnson
Simulation Of Heterosis Effects On Costs Of Pork Production, G. L. Bennett, M. W. Tess, G. E. Dickerson, R. K. Johnson
Department of Animal Science: Faculty Publications
Individual plus maternal heterotic effects on swine production were simulated with a bioeconomic model by changing performance levels of eight traits: -8 d in age at puberty, +3% in conception rate, +.94 in pigs born/litter, +.035 kg in pig birth weight, +2.05 Mcal•sow-1•d -1 in maximum milk output, +8% in preweaning survival, +10.8% in protein growth rate and +17.3% in fat growth rate. Associated heterosis simulated for other traits, such as weaning weights and postweaning gain/feed, was similar to experimental results. Effects of heterosis on biological (feed Mcal/kg) and economic ($/kg) costs were evaluated by simulating two- and …
Individual And Maternal Additive And Heterotic Effects On 205-Day Weight In Beef Cattle, M. D. Macneil, C. A. Dinkel, L. Dale Van Vleck
Individual And Maternal Additive And Heterotic Effects On 205-Day Weight In Beef Cattle, M. D. Macneil, C. A. Dinkel, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Weaning weight records on 47,652 calves in 371 contemporary groups were obtained from the South Dakota Beef Cattle Improvement Association and used to estimate breed individual and maternal additive effects and heterotic effects on 205-d weight. A mixed model was used. Individual additive effects were -22.6 ± 1.3 kg for Red Angus, -19.0 ± 1.1 for Hereford, -12.2 ± .9 for Angus, -11.5 ± 3.1 for Polled Hereford, -10.1 ± 2.2 for Shorthorn, -7.5 ± 4.9 for Tarentaise, 5.3 ± 1.6 for Gelbvieh, 9.5 ± 1.8 for Limousin, 11.4 ± 3.1 for Chianina, 12.4-± 1.2 for Charolais, 14.6 ± 1.2 …
Breed Comparisons For Age And Weight At Puberty In Gilts, L. K. Hutchens, R. L. Hintz, R. K. Johnson
Breed Comparisons For Age And Weight At Puberty In Gilts, L. K. Hutchens, R. L. Hintz, R. K. Johnson
Department of Animal Science: Faculty Publications
Data on 213 purebred and 524 crossbred gilts produced in a four-breed diallel crossing design involving the Duroc (D), Yorkshire (Y), Landrace (L) and Spotted (S)breeds were analyzed for age and weight at puberty. The breed of sire x breed of dam interaction was significant for both age and weight at puberty. However, differences among reciprocals were not significant, and thus, reciprocal means were combined. Crossbreds were younger (7.9 d) and heavier (1.2 kg) at puberty than purebreds. Significant heterosis for age at puberty was found for D X L (-14.3 d),S x D (-12.8 d) and S x L …
Crossbreeding In Swine: Experimental Results, Rodger K. Johnson
Crossbreeding In Swine: Experimental Results, Rodger K. Johnson
Department of Animal Science: Faculty Publications
A review of recent swine crossbreeding experiments is presented and integrated with earlier work. Variation among experiments in observed heterosis for specific crosses was large for reproduction and sow productivity traits. However, standard errors of estimates were also large. It seems likely that heterosis, expressed in absolute values or in percentage units, is different for specific crosses. It is unclear whether these differences are large enough to warrant the use of unique parameter values for comparisons of alternate mating systems. In addition to average heterosis values, average direct and maternal genetic effects are given.