The utilization of Hyparrhenia veld for the nutrition of cattle in the dry season II. Veld hay compared with in situ grazing of the mature forage, and the effects of feeding supplementary nitrogen

Abstract

Three methods of utilizing the natural Hyparrhenia grasslands for the dry-season nutrition of ranch cattle were tested in grazing trials. The feed regimes were:(A) Late-cut veld hay plus aftermath grazing.(B) The accumulated, seasonal growth of mature grass left as ‘standing hay’ for dry-season grazing.(C) A combination of both practices in which half the area was cut for hay, and half left as ‘standing hay’. These treatments were compared with and without the feeding of supplementary protein.Mature Hyparrhenia veld whether cut for hay or left as ‘standing hay’ was a stemmy, low-quality forage deficient in protein. The qualitative deficiency was such that all unsupplemented treatments were equally ineffective in preventing large cattle weight losses in the dry season.The only significant treatment effect was that due to feeding a protein supplement. Otherwise, there were no differences between the three managements, i.e. there was no marked benefit from conserving forage as veld hay compared with in situ grazing of the standing grass.The voluntary intake of veld hay was low; and with heifers, declined to negligible amounts. The feeding of supplementary nitrogen, either as protein or urea, increased the daily hay intake by 140%. As a result, a diet deficient in energy was altered into a productive ration, with consequent cattle weight gains.Although the cattle preferentially sought-after, and grazed the aftermath from late-cut veld hay; its practical nutritional value was slight, and was not reflected in cattle weight gains.