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A note on observations on the effect of photostimulation and hormone treatment on the oestrous activity and lambing performance of North Country Cheviot ewes

Published online by Cambridge University Press:  27 March 2009

J. J. Robinson  and
J. C. Gill
J. J. Robinson
Affiliation:
Rowett Research Institute, Buchsburn, Aberdeen, Ab2 9 Sb
J. C. Gill
Affiliation:
Rowett Research Institute, Buchsburn, Aberdeen, Ab2 9 Sb
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Summary

Twelve non-pregnant and 20 pregnant North Country Cheviot ewes due to lamb in April 1969 were subjected to an 18 h daylength during the previous December. Thereafter daylength was reduced by 25 min per week. Eight ewes mated naturally in late May and early June and 22 of the remainder mated within 6 days after treatment with progesterone and gonadotrophin. Five of the photostimulated and 14 of the photostimulated plus hormone-treated ewes subsequently lambed in November 1969. The lambs were weaned at 28 days and 16 of the ewes were returned to fertile rams immediately after weaning. All 16 ewes were re-mated to naturally occurring oestrus during January-February 1970 and 13 proved pregnant.

Type
Short Note
Information
The Journal of Agricultural Science , Volume 77 , Issue 2 , October 1971 , pp. 343 - 345
Copyright
Copyright © Cambridge University Press 1971

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