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Full-Text Articles in Animal Sciences
Combined Purebred And Crossbred Genetic Evaluation Of Columbia, Suffolk, And Crossbred Lamb Birth And Weaning Weights: Systematic Effects And Heterogeneous Variances, Napoleón Vargas Jurado, David R. Notter, Joshua B. Taylor, Daniel J. Brown, Michelle R. Mousel, Ronald M. Lewis
Combined Purebred And Crossbred Genetic Evaluation Of Columbia, Suffolk, And Crossbred Lamb Birth And Weaning Weights: Systematic Effects And Heterogeneous Variances, Napoleón Vargas Jurado, David R. Notter, Joshua B. Taylor, Daniel J. Brown, Michelle R. Mousel, Ronald M. Lewis
Department of Animal Science: Faculty Publications
Despite the benefits of crossbreeding on animal performance, genetic evaluation of sheep in the U.S. does not directly incorporate records from crossbred lambs. Crossbred animals may be raised in different environments as compared to purebreds. Systemic factors such as age of dam and birth and rearing type may, therefore, affect purebred and crossbred performance differently. Furthermore, crossbred performance may benefit from heterozygosity, and genetic and environmental variances may be heterogeneous in different breeds and their crosses. Such issues must be accounted for in a combined (purebred and crossbred) genetic evaluation. The objectives of this study were to i) determine the …
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 …
Responses To 19 Generations Of Litter Size Selection In The Ne Index Line. Ii. Growth And Carcass Responses Estimated In Pure Line And Crossbred Litters, D. B. Petry, J. W. Holl, R. K. Johnson
Responses To 19 Generations Of Litter Size Selection In The Ne Index Line. Ii. Growth And Carcass Responses Estimated In Pure Line And Crossbred Litters, D. B. Petry, J. W. Holl, R. K. Johnson
Department of Animal Science: Faculty Publications
Our objective was to estimate responses in growth and carcass traits in the NE Index line (I) that was selected for 19 generations for increased litter size. Differences between Line I and the randomly selected control line (C) were estimated in pure line litters and in F1 and three-way cross litters produced by mating I and C females with males of unrelated lines. Contrasts of means were used to estimate the genetic difference between I and C and interactions of line differences with mating type. In Exp 1, 694 gilts that were retained for breeding, including 538 I and …
Responses To 19 Generations Of Litter Size Selection In The Nebraska Index Line. I. Reproductive Responses Estimated In Pure Line And Crossbred Litters, D. B. Petry, Rodger K. Johnson
Responses To 19 Generations Of Litter Size Selection In The Nebraska Index Line. I. Reproductive Responses Estimated In Pure Line And Crossbred Litters, D. B. Petry, Rodger K. Johnson
Department of Animal Science: Faculty Publications
Our objective was to estimate responses in reproductive traits in the Nebraska Index line (I) after 19 generations of selection for increased litter size. Responses were estimated in dams producing pure line, F1, and three-way cross litters. A total of 850 litters were produced over six year-seasons, including 224 pure line litters, 393 F1 litters produced from I and C females mated with DanbredNALandrace (L) or Duroc- Hampshire (T) boars, and 233 litters by F1 L x I and L x C females mated with T boars. Contrasts of means were used to estimate the genetic …
Estimates Of Parameters Between Direct And Maternal Genetic Effects For Weaning Weight And Direct Genetic Effects For Carcass Traits In Crossbred Cattle, R. K. Splan, Larry V. Cundiff, M. E. Dikeman, L. Dale Van Vleck
Estimates Of Parameters Between Direct And Maternal Genetic Effects For Weaning Weight And Direct Genetic Effects For Carcass Traits In Crossbred Cattle, R. K. Splan, Larry V. Cundiff, M. E. Dikeman, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Estimates of heritabilities and genetic correlations were obtained for weaning weight records of 23,681 crossbred steers and heifers and carcass records from 4,094 crossbred steers using animal models. Carcass traits included hot carcass weight; retail product percentage; fat percentage; bone percentage; ribeye area; adjusted fat thickness; marbling score, Warner- Bratzler shear force and kidney, pelvic and heart fat percentage. Weaning weight was modeled with fixed effects of age of dam, sex, breed combination, and birth year, with calendar birth day as a covariate and random direct and maternal genetic and maternal permanent environmental effects. The models for carcass traits included …
Estimation Of Direct And Maternal Breed Effects For Prediction Of Expected Progeny Differences For Birth And Weaning Weights In Three Multibreed Populations, F. A. Rodriguez-Almeida, L. Dale Van Vleck, K. E. Gregory
Estimation Of Direct And Maternal Breed Effects For Prediction Of Expected Progeny Differences For Birth And Weaning Weights In Three Multibreed Populations, F. A. Rodriguez-Almeida, L. Dale Van Vleck, K. E. Gregory
Department of Animal Science: Faculty Publications
Direct and maternal breed effects on birth and 200-d weights were estimated for nine parental breeds (Hereford [H], Angus [A], Braunvieh [B], Limousin [L], Charolais [C], Simmental [S], Gelbvieh [G], Red Poll [R], and Pinzgauer [P]) that contributed to three composite populations (MARC I = ¼B, ¼C, ¼L, ⅛H, ⅛A; MARC II = ¼G, ¼S, ¼H, ¼A; and MARC III = ¼R, ¼P, ¼H, ¼A). Records from each population, the composite plus pure breeds and crosses used to create each composite, were analyzed separately. The animal model included fixed effects of contemporary group (birth year-sex-dam age), proportions of individual and …
Prediction Of Breeding Values For Tenderness Of Market Animals From Measurements On Bulls, K. L. Barkhouse, L. Dale Van Vleck, Larry V. Cundiff, M. Koohamaraie, D. D. Lunstra, J. D. Crouse
Prediction Of Breeding Values For Tenderness Of Market Animals From Measurements On Bulls, K. L. Barkhouse, L. Dale Van Vleck, Larry V. Cundiff, M. Koohamaraie, D. D. Lunstra, J. D. Crouse
Department of Animal Science: Faculty Publications
Data were tenderness measures on steaks from 237 bulls (Group II) slaughtered after producing freezable semen and on 1,431 related steers and heifers (market animals, Group I ) from Angus, Hereford, Pinzgauer, Brahman, and Sahiwal crosses from the Germ Plasm Evaluation project at the U.S. Meat Animal Research Center. Tenderness was assessed through Warner-Bratzler Shear Force (SF), taste panel tenderness (TPT), marbling score (MS), and myofibrillar fragmentation index (MFI). For all traits, as fraction Bos indicus inheritance increased, implied tenderness decreased. Heritability estimates were generally not significantly different from zero. Genetic correlations generally indicated favorable associations among the traits. The …
Estimated Breeding Values For Meat Characteristics Of Crossbred Cattle With An Animal Mode1, L. Dale Van Vleck, A. F. Hakim, Larry V. Cundiff, R. M. Koch, J. D. Crouse, K. G. Boldman
Estimated Breeding Values For Meat Characteristics Of Crossbred Cattle With An Animal Mode1, L. Dale Van Vleck, A. F. Hakim, Larry V. Cundiff, R. M. Koch, J. D. Crouse, K. G. Boldman
Department of Animal Science: Faculty Publications
Longissimus muscle area, shear force measure, and sensory panel scores for flavor, juiciness, and tenderness, and marbling score were obtained from 682 steer carcasses, resulting from crosses among five Bos taurus and Bos indicus breeds. The single-trait model used included birth year and as covariates breed fractions, weaning age, and days on feed. The numerator relationship matrix was for 1,350 animals (682 steers, 74 pure breed and 52 F1-cross sires and 542 dams). The coefficient matrix was inverted to examine standard errors of prediction. Estimated breeding value is the sum of the estimate of genetic deviation and the weighted (fractions) …
Sow Productivity Comparisons For Four Breeds Of Swine: Purebred And Crossbred Litters, H. R. Gaugler, D. S. Buchanan, R. L. Hintz, R. K. Johnson
Sow Productivity Comparisons For Four Breeds Of Swine: Purebred And Crossbred Litters, H. R. Gaugler, D. S. Buchanan, R. L. Hintz, R. K. Johnson
Department of Animal Science: Faculty Publications
Data were collected from 366 litters produced in a four-breed (Duroc, Yorkshire, Spotted and Landrace) diallel mating system. Purebred and crossbred litters were farrowed during five consecutive (fall and spring) farrowing seasons (fall 1976 through fall 1978). Litters were produced by randomly mating boars of each breed to at least one female of each breed. Litter size and weight at birth, litter size and weight at 42 d and pig survival to 42 d were analyzed. There were significant parity effects for all traits except survival rate, and significant year and season effects for litter size at birth and 42 …
Simulation Of Breed And Crossbreeding Effects On Costs Of Pork Production, G. L. Bennett, W. M. Tess, G. E. Dickerson, R. K. Johnson
Simulation Of Breed And Crossbreeding Effects On Costs Of Pork Production, G. L. Bennett, W. M. Tess, G. E. Dickerson, R. K. Johnson
Department of Animal Science: Faculty Publications
A bio-economic model of swine production was used to simulate expected performance effects of breeds in alternative breeding systems on total costs/100 kg of live weight (EWW) or/l00 kg lean (ELW) for marketing at 100 kg live weight and on costs/100 kg lean for marketing at mean 185-d weight (ELA). Effects of heterosis and of six U.S. breeds were simulated for integrated industry purebred (P), two-breed specific (2S), backcross (2B) and rotation cross (2R), and three-breed specific (3S) and rotation cross (3R) breeding systems. Traits considered were age at puberty (-PUB), conception rate (CR), litter size born alive (NBA), preweaning …
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 …
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.