Effect of Winter Nutrition and Lactation on Ovulation and Ovulation Rate in Ewes in Autumn
نویسنده
چکیده
The effect of undernutrition during July-September on oestrus and ovulation rate in Janury-April was investigated in lactating and dry Corriedale ewes. The low levels of nutrition imposed from July resulted in a 5 to 10 kg difference in liveweight in September but thereafter liveweights had equilibrated with control ewes by December. This undernutrition decreased the probability of ovulating early in the breeding season but had no effect on the proportion of ewes with multiple ovulations at any time. The effect of lactation in July-September resulted in a lower incidence of oestrus and also reduced ovulation rate in the following Autumn. It is concluded that following a Winter drought producers ought to delay joining or extend the normal joining period.
منابع مشابه
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