Abstract:
Two trial were conducted to determine the possible effects of season, protein supplementation, age and birth status on the reproduction rate (ovulation rate and rate of twinning) of ewes. In Trial 1 the weight, age and birth status if ewes were recorded. 144 ewes were randomly allocated in two treatment groups (urea and mix protein group) synchronised, mated and the number of corpora lutea, foetuses observed, lambs born per ewe and the mass of the ewe after lambing were also recorded. Lambing status or the 1-year-old (0.993 ± 0.316) and 2-year-old (1.233 ± 0.134) ewes were lower (p < 0.05) than that of the 6- year-old ewes (1.897 ± 0.248). The lambing status and the number of corpora lutea of the single born ewes (1.179 ± 0.131; 1.274 ± 0.138) were lower (p < 0.0001) than that of the twin born ewes (1.614 ± 0.139; 1.782 ± 0.147), within the urea treatment. In Trial 2, 75 ewes were randomly allocated in four treatment groups (raw lupins, cooked lupins, cottonseed oil-cake and Fescue grass), synchronised and the number of corpora lutea were recorded. The weight, age and birth status of the ewes were also recorded. The number of corpora lutea from the cooked lupin group (1.815 ± 0.184) was significantly higher than that from the cottonseed oilcake group (1.048 ± 0.209), within the twin born ewe group. It was concluded that season, protein supplementation, age and birth status influenced the reproduction rate of ewes. Copyright
