The effects of liveweight, and of the quality of the feed given previously, on the ad libitum intakes of a poor quality hay by sheep of 5 breeds of different mature liveweights

摘要

Systems exist to predict the daily rate at which a sheep will eat a particular food In these, it is conventional to describe the sheep only by some function of it's liveweight, W. Such systems predict that sheep of breeds with different values of mature liveweight (A), will, at the same W, have the same daily rate of food intake. There is no reason a priori why this should be so, but there is little experimental evidence for or against. On high quality foods, which do not constrain the rate of intakethrough their bulk, there are reasons (Emmans et al, 1987, Animal Production, 44, 476) for expecting intake, at a given W, to differ between sheep of different A. The purpose of the work described here was to measure the intakes of a poor quality hay (H) at different values of W for sheep of breeds with a range of values of A. The effect of the quality of the food given until, and between, the tests on the intake of H was also measured.