| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
* Department of Animal Science and
and
Department of Statistics, Iowa State University, Ames 50011
2 Correspondence:
109 Kildee Hall, Iowa State University, Ames, IA 50011 (phone: 515-294-6728; fax: 515-294-5698; E-mail:
tjbaas{at}iastate.edu).
Records on 361,300 Yorkshire, 154,833 Duroc, 99,311 Hampshire, and 71,097 Landrace pigs collected between 1985 and April of 2000 in herds on the National Swine Registry Swine Testing and Genetic Evaluation System were analyzed. Animal model and REML procedures were used to estimate random effects of animal genetic, common litter, maternal genetic, and the covariances between animal and maternal for lean growth rate (LGR), days to 113.5 kg (DAYS), backfat adjusted to 113.5 kg (BF), and loin eye area adjusted to 113.5 kg (LEA). Fixed effects of contemporary group and sex were also in the statistical model. Based on the single-trait model, estimates of heritabilities were 0.44, 0.44, 0.46, and 0.39 for LGR; 0.35, 0.40, 0.44, and 0.40 for DAYS; 0.48, 0.48, 0.49, and 0.48 for BF; and 0.33, 0.32, 0.35, and 0.31 for LEA in the Yorkshire, Duroc, Hampshire, and Landrace breeds, respectively. Estimates of maternal genetic effects were low and ranged from 0.01 to 0.05 for all traits across breeds. Estimates of common litter effects ranged from 0.07 to 0.16. A bivariate analysis was used to estimate the genetic correlations between lean growth traits. Average genetic correlations over four breeds were -0.83, -0.37, 0.44, -0.07, 0.08, and -0.37 for LGR with DAYS, BF, and LEA, DAYS with BF and LEA, and BF with LEA, respectively. Average genetic trends were 2.35 g/yr, -0.40 d/yr, -0.39 mm/yr, and 0.37 cm2/yr for LGR, DAYS, BF, and LEA, respectively. Results indicate that selection based on LGR can improve leanness and growth rate simultaneously and can be a useful biological selection criterion.
Key Words: Genetic Parameters • Genetic Trend • Growth • Pigs
This article has been cited by other articles:
|
|
 |
|
  C. R. Schwab, T. J. Baas, K. J. Stalder, and J. W. Mabry Deposition rates and accretion patterns of intramuscular fat, loin muscle area, and backfat of Duroc pigs sired by boars from two time periods J Anim Sci, June 1, 2007; 85(6): 1540 - 1546. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. R. Schwab, T. J. Baas, K. J. Stalder, and J. W. Mabry Effect of long-term selection for increased leanness on meat and eating quality traits in Duroc swine J Anim Sci, June 1, 2006; 84(6): 1577 - 1583. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. B. Edwards, R. J. Tempelman, and R. O. Bates Evaluation of Duroc- vs. Pietrain-sired pigs for growth and composition J Anim Sci, February 1, 2006; 84(2): 266 - 275. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Chen, T. J. Baas, J. W. Mabry, and K. J. Koehler Genetic correlations between lean growth and litter traits in U.S. Yorkshire, Duroc, Hampshire, and Landrace pigs J Anim Sci, July 1, 2003; 81(7): 1700 - 1705. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Chen, T. J. Baas, J. C. M. Dekkers, K. J. Koehler, and J. W. Mabry Evaluation of strategies for selection for lean growth rate in pigs J Anim Sci, May 1, 2003; 81(5): 1150 - 1157. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
