Compensatory Growth of Cattle on the Natural Grasslands of Northern Rhodesia

Abstract

ON the natural grasslands of Northern Rhodesia cattle gain weight during the rainy season, but during the subsequent dry season they frequently lose up to 15 per cent, and in some cases as much as 25 per cent, of their previous maximum weight. It is well known that the greater the restriction in feed supply the greater the gain in weight on subsequent realimentation^1–4. The degree of compensatory growth was measured for the indigenous (Bos indicus) Sanga and Zebu cattle (oxen). The level of nutrition was varied during the dry season to produce a range of changes in weight from slightly above maintenance to large losses, and the gains in the following rainy season were observed when all the cattle were grazed as one herd on the natural veld. A summary of the results is given in Table 1. Each age-group trial began at the end of a rainy season during which all the cattle had been under the same conditions. About one-fifth of the cattle were used in more than one year. The stocking-rate was such that ample forage was available during the rains, and the nutrition of the cattle was restricted only by the seasonal decline in the nutritive quality of the grasslands.