An experiment was carried out to characterize key reproduction and production
traits of sheep in southern Sinai. A free choice cafeteria feeding system was adopted
to study diet selection and voluntary food intake and to insure nutrition is not a limiting
factor. Eighty-five ewes in four groups were used. The control group was fed
according to NRC standards throughout. Ewes in the three experimental groups were
offered ad lib one of three basal roughages; berseem hay, one-third hay plus rice
straw and rice straw plus a molasses-urea mixture. Roughages were made available
ad lib throughout the experiment and comprised the sole ration during the early
pregnancy stage. Thereafter, and up to weaning of offspring they were offered free
choice in separate feeders ground corn grains and cottonseed meal. The hay-fed ewes appeared to select diets that satisfied their energy and
protein requirements during the different stages of the production cycle and
maintained optimum proportions of roughage and rumen degradable protein in their
daily dry matter intake. The straw-fed ewes, on the other hand, failed to control their
intake as per physical and physiological needs especially during early pregnancy and
through lactation At the start of the experiment the ewes were not in their optimum condition,
weighing only about 75% of adult weight. After lambing, control and hay-fed ewes
attained optimum weights whereas straw-fed ewes nearly maintained their weights
before breeding irrespective of receiving free choice concentrates during the late
pregnancy stage onward. Hay-fed ewes performed similar or better than the controls throughout. Straw-
fed ewes, even with free choice concentrates, had low fertility (lambing rates), high
lamb and ewe mortality, low milk production, smaller birth weights of offspring. The
ewe production index (kg lambs weaned per 100 ewes joined to ram) was 1765 and
1983 kg for the control and hay-fed ewes, and only 1197 and 672 kg for the hay-straw
and straw-Mufeed groups. However, these may not be the consequence of feeding straw per se. The
control diets contained straw contributing about one-third of the roughage in the diet or
about 15% of total dry matter intake. Rather, it is the art of balancing the rations in the
light of recent advances in nutrition and the allied sciences that makes the difference.