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Opportunities and possible methods to improve reproduction in the pig

Published online by Cambridge University Press:  27 February 2018

Rodger K. Johnson
Affiliation:
Animal Science Department, University of Nebraska, Lincoln NE 68583-0908
Steven M. Neal
Affiliation:
Agricultural Technical Institute, The Ohio State University, Wooster OH 44691
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Extract

Genetic selection for litter size received little attention either by scientists or commercial pig breeders until recently. Low heritability of litter size, its sex-limited expression and the fact that it cannot be measured until reproductive maturity are often given as reasons. But the major reason may be that the reproductive rate of pigs is already quite high, and the economic value of genetic changes in litter size have been small relative to those of efficiency and composition of growth.

The economics of pig production have changed and technological and biological advances have caused us to re-examine the economic value of traits. Reducing fat in the carcass and more efficient conversion of feed to lean meat have always been, and will continue to be, high priority selection objectives for pig breeders. But expensive, environmentally controlled gestation, farrowing and nursery houses are the norm of modern pig production and increasing litter size will result in a significant reduction in the cost of producing lean meat (Tess et al., 1983).

Type
Trait Improvement
Copyright
Copyright © British Society of Animal Production 1988

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References

LITERATURE CITED

Avalos, E. and, Smith, C. 1987. Genetic improvement of litter size in pigs. Anim. Prod. 44: 153164.Google Scholar
Bichard, M. and, David, P. 1985. Effectiveness of genetic selection for prolificacy in pigs. J. Reprod. Fert., Suppl. 33: 127138.Google ScholarPubMed
Cunningham, P. J., England, M. E., Young, L. D, and, Zimmerman, D. R. 1979. Selection for ovulation rate in swine: Correlated response in litter size and weight. J. Anim. Sci. 48: 509516.Google Scholar
Hill, W. G. and, Webb, A. J. 1982. Genetics of reproduction in the pig. In Control of Pig Production (ed. Cole, D. J. A. and Foxcroft, G. R.), pp. 541564. Butterworths, London.Google Scholar
Johnson, R. K., Zimmerman, D. R. and, Kittok, R. J. 1984. Selection for components of reproduction in swine. Livest. Prod. Sci. 11: 541558.CrossRefGoogle Scholar
Legault, C. 1983. Breeding for large litters in swine. Prod. Pork Industry Conf., Urbana, Ill. pp. 126.Google Scholar
Legault, C. 1985. Selection of breeds, strains and individual pigs for prolificacy. J. Reprod. Fert., Suppl. 33: 151166.Google ScholarPubMed
Leymaster, K. A., Christenson, R. K. and, Young, L. D. 1986. A biological model to measure uterine potential for litter size in swine. Proc. 3rd World Cong. Genet. Appl. Livest. Prod. 11: 209214.Google Scholar
Neal, Steven M. 1987. Selection for components of litter size in swine. Response to five generations of selection and expected response for alternate selection methods. Ph.D. Dissertation. University of Nebraska, Lincoln.Google Scholar
Ollivier, L. and, Bolet, G. 1981. Selection for litter size in the pig: results of a 10 generation selection experiment. Journées de la Recherche Porcine en France 13: 261268.Google Scholar
Ollivier, L. 1982. Selection for prolificacy in the pig. Pig News and Information 3: 383388.Google Scholar
Rutledge, J. J. 1980. Fraternity size and swine production. I. Effect on fecundity of gilts. J. Anim. Sci. 51: 868870.Google Scholar
Tess, M. W., Bennett, G. L. and, Dickerson, G. E. 1983. Simulation of genetic changes in life cycle efficiency of pork production. II. Effects of components on efficiency. J. Anim. Sci. 56: 354368.Google Scholar
Tomes, G. T. and, Nielsen, H. E. 1985. Some aspects of selection for increased reproductive performance in sow herds. Anim. Breed. Abstr. 53: 1494 (Abstr.).Google Scholar
Van Der Steen, H. A. M. 1983. Maternal and genetic influences on production and reproduction in pigs. Ph.D. Dissertation. Agricultural University, Wageningen, Netherlands.Google Scholar