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Ten Generations Of Selection For Predicted Weight Of Testes In Swine: Direct Response And Correlated Response In Body Weight, Backfat, Age At Puberty, And Ovulation Rate, Rodger K. Johnson, Gregg R. Eckardt, Thomas A. Rathje, Denise K. Drudik
Ten Generations Of Selection For Predicted Weight Of Testes In Swine: Direct Response And Correlated Response In Body Weight, Backfat, Age At Puberty, And Ovulation Rate, Rodger K. Johnson, Gregg R. Eckardt, Thomas A. Rathje, Denise K. Drudik
Department of Animal Science: Faculty Publications
Selection for predicted weight of testes at 150 d of age (PWT) was practiced for 10 generations to determine the effect on reproductive and growth traits in swine. Mass selection among boars (line TS) or random selection (line C) was practiced beginning with the F3 generation of a Large White x Landrace composite population. Population size in each line was 40 to 45 litters by 15 sires per generation. Responses were estimated by regressions on cumulative selection differentials for PWT and on generation number and by mixed-model derivative-free REML procedures. The realized heritability of PWT was .35 ± .02 and …
Estimates Of Genetic Parameters For 320-Day Pelvic Measurements Of Males And Females And Calving Ease Of 2-Year-Old Females, L. A. Kriese, L. Dale Van Vleck, K. E. Gregory, K. G. Boldman, Larry V. Cundiff, R. M. Koch
Estimates Of Genetic Parameters For 320-Day Pelvic Measurements Of Males And Females And Calving Ease Of 2-Year-Old Females, L. A. Kriese, L. Dale Van Vleck, K. E. Gregory, K. G. Boldman, Larry V. Cundiff, R. M. Koch
Department of Animal Science: Faculty Publications
Records from 12 breed groups collected from 1983 to 1991, included in the Germ Plasm Utilization project at the U.S. Meat Animal Research Center, were analyzed separately by breed group and combined to estimate heritabilities and genetic correlations for 320-d male and female pelvic width, height, and area, and for 320-d male pelvic and female 2-yr-old calving ease. Calving ease was analyzed as a trait of the dam using 1) actual and 2) binary scale calving ease scores with a covariate of calf birth weight. A bivariate animal model and derivative-free REML incorporating sparse matrix techniques were used. When breed …