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The effect of reduction in daylength, level of feeding and age on the reproduction of young female sheep mated at an induced ovulation

Published online by Cambridge University Press:  02 September 2010

R. M. H. Al-Wahab  and
M. J. Bryant
R. M. H. Al-Wahab
Affiliation:
Department of Agriculture and Horticulture, University of Reading Ear ley Gate, Reading, RG6 2 AT
M. J. Bryant
Affiliation:
Department of Agriculture and Horticulture, University of Reading Ear ley Gate, Reading, RG6 2 AT
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Abstract

Fifty-six young female Suffolk × (Cadzow Improver × Scottish Blackface) sheep were used in a 2 × 2 × 2 factorial experiment investigating: (i) change in daylength (constant C v. reduced R), (ii) level of feeding (to appetite, H, v. 75% of that allowance, L), and (iii) age at hormone treatment (20 v. 28 weeks). At the appropriate age, the sheep were treated with a progestagen (MAP) and 750 i.u. PMS, inseminated, and slaughtered 26 days later. In a second experiment, change in daylength and level of feeding only were investigated. Hormone treatment took place at 20 weeks of age. In both years, all sheep showed oestrous behaviour and ovulated. A greater number of sheep yielded embryos on C than on R treatments (P<0·05 in Year 2), but no effect of feed level or age was found. Of those sheep not yielding embryos, a greater number on R than on C treatments showed a second ovulation at 20 weeks but not at 28 weeks.

Type
Research Article
Information
Animal Production , Volume 26 , Issue 3 , June 1978 , pp. 317 - 324
Copyright
Copyright © British Society of Animal Science 1978

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References

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