Guideline for the management of the nutrition of flocks in West Asia during the dry and mating periods: what information do we have and what we need?
1995
Treacher, T.T. (Cordoba Univ. (Spain). Dept. de Produccion Animal)
Lambing percentages of less than 80 percent are common in Awassi flocks in West Asia. Although the Awassi breed is inherently seasonal in its oestrous activity, surveys show great seasonality of lambing, with a peak in winter which appears to relate to the increase in oestrous activity which occurs when nutrition improves in summer and autumn when stubbles and residues of irrigated crops are grazed. This offers the prospect that improved management of nutrition could lead to increased lambing percentages. Increasing fertility, without any change in ewe fecundity, from 80 percent to 95 percent, would result in a 19 percent increase in potential flock performance. This paper reviews recent work on effects of body condition and nutrition at mating on ovulation rate, on stocking rate and supplementation on the performance of ewes grazing stubble and mineral and vitamin deficiencies, which offer tentative guide-lines for managing Awassi ewes in the dry and mating periods
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