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Effect of boar exposure on expression of genetic potential for age of puberty in gilts

Published online by Cambridge University Press:  02 September 2010

T. J. Safranski
Affiliation:
Department of Animal Sciences, University of Missouri, Columbia, Missouri 65211, USA
W. R. Lamberson
Affiliation:
Department of Animal Sciences, University of Missouri, Columbia, Missouri 65211, USA
R. O. Bates
Affiliation:
Department of Animal Sciences, University of Missouri, Columbia, Missouri 65211, USA
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Abstract

Genotype × environment interaction for age at puberty was evaluated using gilts from the Nebraska Gene Pool population derived from lines selected randomly (RS; no. = 48) or for seven generations for decreased age at puberty (AP; no. = 73). Age at puberty was evaluated in two environments: boar exposure for 15 min daily (BE) or no boar exposure (NBE). Pigs were randomly assigned to treatment and mixed into groups of 20 in pasture lots. Oestrous detection was initiated when the oldest gilt in a pen was 125 days of age. Blood samples were taken weekly and assayed for progesterone. Gilts were considered to have expressed oestrus if they exhibited lordosis or had consecutive weekly blood samples with progesterone values above 6·4 × 109 mol/1 (2 μ, g/l). Gilts were removed from the pen upon confirmation of puberty or at 250 days of age. Two gilts failed to reach puberty by 250 days so this value was assigned as their age at puberty. Least-squares analyses of variance were used to analyse the data. A model including line, sire within line, farrowing group, treatment and line × treatment interaction was fitted to the dependent variables age at puberty and percentage cycling by 185 days. Line and treatment each affected age at puberty (P < 0·05) but did not interact. Least-square mean ages at puberty were 154 (s.e. 4·5), 164 (s.e. 4·7), 164 (s.e. 6·1) and 179 (s.e. 5·9) days for AP-BE, AP-NBE, RS-BE and RS-NBE, respectively. Treatment affected percentage of gilts cycling by 185 days (P < 0·05). Least-square percentages were 91 (s.e. 6·9), 76 (s.e. 71), 84 (s.e. 9·2) and 65 (s.e. 8·9) % for AP-BE, AP-NBE, RS-BE and RS-NBE, respectively. These results indicate that expression of response to selection for decreased age at puberty in the gilt is not dependent on stimuli from the boar.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1991

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References

REFERENCES

Bronson, F. H. and Maruniak, J. A. 1975. Male-induced puberty in female mice: evidence for a synergistic action of social cues. Biology of Reproduction 13: 9498.CrossRefGoogle ScholarPubMed
Deligeorgis, S. G., Lunney, D. C. and English, P. R. 1984. A note on efficacy of complete v. partial boar exposure on puberty attainment in the gilt. Animal Production 39: 145147.Google Scholar
Drickamer, L. C. 1979. Acceleration and delay of first vaginal estrus in wild stocks of Mus musculus. Journal of Mammology 60: 215216.CrossRefGoogle Scholar
Drickamer, L. C. 1981a. Selection for age of sexual maturation in mice and the consequences for population regulation. Behavioral and Neural Biology 31: 8289.CrossRefGoogle Scholar
Drickamer, L. C. 1981b. Acceleration and delay of sexual maturation in female house mice previously selected for early and late first vaginal oestrus. Journal of Reproduction and Fertility 63: 325329.CrossRefGoogle ScholarPubMed
Flowers, B., Cantley, T. C., Martin, M. J. and Day, B. N. 1989. Effect of elevated ambient temperatures on puberty in gilts. Journal of Animal Science 67: 779784.CrossRefGoogle ScholarPubMed
Harvey, W. R. 1987. User's guide for LSMLMW mixed model least-squares and maximum likelihood computer program PC-1 version. Ohio State Univ., Columbus. (Mimeo).Google Scholar
Hemsworth, P. H., Hansen, C., Winfield, C. G. and Barnett, J. L. 1988. Effects on puberty attainment in gilts of continuous or limited exposure to boars. Australian Journal of Experimental Agriculture 28: 469472.CrossRefGoogle Scholar
Hughes, P. E. 1982. Factors affecting the natural attainment of puberty in the gilt. In Control of Pig Reproduction (ed. Cole, D. J. A. and Foxcroft, G. R.), pp. 117138. Butterworths, London.CrossRefGoogle Scholar
Jensen, A. H., Yen, J. T., Gehring, M. M., Baker, D. H., Becker, D. E. and Harmon, B. G. 1970. Effects of space restriction and management on preand post-puberal response of female swine. Journal of Animal Science 31: 745750.CrossRefGoogle Scholar
Karlbom, I. 1981/1982. Attainment of puberty in female pigs: influence of boar stimulation. Animal Reproduction Science 4: 313319.CrossRefGoogle Scholar
Kinsey, R. E., Carlson, R., Proud, C. and Zimmerman, D. R. 1976. Influence of boar component stimuli on age at puberty in gilts. Journal of Animal Science 42: 1362 (Abstr.).Google Scholar
Kirkwood, R. N., Forbes, J. M. and Hughes, P. E. 1981. Influence of boar contact on attainment of puberty in gilts after removal of the olfactory bulbs. Journal of Reproduction and Fertility 61: 193196.CrossRefGoogle ScholarPubMed
Kirkwood, R. N. and Hughes, P. E. 1980. A note on the efficacy of continuous v. limited boar exposure on puberty attainment in the gilt. Animal Production 31: 205207.Google Scholar
Lamberson, W. R., Johnson, R. K., Zimmerman, D. R. and Long, T. E. 1991. Direct responses to selection for increased litter size, decreased age at puberty or random selection following selection for ovulation rate in swine. Journal of Animal Science In press.Google Scholar
Mavrogenis, A. P. and Robison, O. W. 1976. Factors affecting puberty in swine. Journal of Animal Science 42: 12511255.CrossRefGoogle ScholarPubMed
Melrose, D. R., Reed, H. C. B. and Patterson, R. L. S. 1971. Androgen steroids associated with boar odour as an aid to the detection of oestrus in pig artificial insemination. British Veterinary Journal 127: 497502.CrossRefGoogle Scholar
Pearce, G. P., Hughes, P. E. and Booth, W. D. 1988. the involvement of boar submaxillarly salivary gland secretions in boar-induced precocious puberty attainment in the gilt. Animal Reproduction Science 16: 125134.CrossRefGoogle Scholar
Salmon-Legagneur, E. 1970. [A study of some of the factors in the variation of age and weight of Large White sows at first oestrus.] Journées de la Recherche Porcine en France, pp. 4146. Animal Breeding Abstracts 39: (1971), 554 (Abstr.).Google Scholar
Scheimann, C. A., England, D. C. and Kennick, W. H. 1976. Initiating estrus in prepubertal confinement gilts. Journal of Animal Science 43: 210 (Abstr.).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. Journal of Animal Science 56: 354368.CrossRefGoogle Scholar
Vandenbergh, J. G. 1967. Effect of the presence of a male on the sexual maturation of female mice. Endocrinology 81: 345349.CrossRefGoogle ScholarPubMed
Vandenbergh, J. G. 1969. Male odor accelerates female sexual maturation in mice. Endocrinology 84: 658660.CrossRefGoogle ScholarPubMed
Zimmerman, D. R., Carlson, R. and Nippert, L. 1969. Age at puberty in gilts as affected by daily heat checks with a boar. Journal of Animal Science 29: 203 (Abstr.).Google Scholar