COMPENSATORY GROWTH IN SHEEP AND CATTLE .1. GROWTH-PATTERN AND FEED-INTAKE

Sheep and cattle often exhibit compensatory growth following nutrition al restriction. Complete compensation, that is the same weight at the same age as non-restricted contemporaries, has often been observed in sheep but not in cattle.In this experiment the compensatory growth of sheep and cattle was measured after their nutrition had been restricte d sufficiently to induce losses in body weight. The growth, feed intak e and feed conversion efficiency of the compensating sheep and cattle, measured during re-alimentation, was compared to control animals fed ad libitum throughout the experiment. A high-quality diet was used to maximize the opportunity for compensatory growth. The cattle exhibited compensatory growth for the 11 months between re-alimentation and the end of the experiment, and were able to compensate completely. Compen satory growth did not persist as long in the sheep as in the cattle, a nd they remained lighter than the controls at the end of the experimen t. During the first 12 weeks of re-alimentation there was no differenc e in the feed intake of the compensating and control animals in both s pecies. Compensatory growth during this time was due to the greater ef ficiency of the compensating animals. After this initial 12 weeks the feed intake of the compensating animals increased, and the subsequent compensatory growth could be fully accounted for by greater feed intak e. The greater persistence of compensatory growth in the cattle was du e to their intake remaining elevated longer.