Feeding whole grain wheat to drought affected Angora goats, the influence of roughage on adaptation and estimate of energy requirements for maintenance

Abstract: This work investigated the feeding of whole grain wheat to goats to determine the requirement if any, for roughage during maintenance feeding; the amount of wheat required to maintain goats; and the health of goats fed whole grain wheat. The experiment used 30 drought affected Angora goats (mean live weight 20.1±0.4kg) for 23 weeks. Wheat (ME 13.73MJ/kg DM) or wheat, 800 and chopped hay 200g/kg (total ration ME 13.22MJ/kg DM) were fed as sole rations, at maintenance, for 23 weeks and some goats were grazed on drought affected pasture with strategic supplementation of wheat and hay when required. Despite careful introduction of whole wheat, three goats were removed for inappetence. Only one half of goats adapted to entire wheat diets within 4 weeks. The remaining goats exhibited cycles of rejection of whole wheat and required on average 350g/kg of hay in order to consume a maintenance diet. Even with a diet notionally of 800g/kg whole wheat plus 200g/kg hay some goats required an average intake of 350g/kg of hay in order to maintain live weight, with the average intake of hay in this treatment being 236g/kg of dry matter. There was no affect of diet on mohair growth or quality. Plasma Vitamin E concentration was significantly higher for goats grazing pasture than those on wheat, and those with access to hay had significantly higher concentrations than those on wheat only (2.79, 1.02, and 0.67mg/l respectively; P<0.001). The ME requirement for live weight maintenance was 428kJ/kg0.75/d. The energy diverted to mohair growth at maintenance averaged 7.4kJME/kg0.75/d. It was concluded that long-term feeding of whole wheat to Angora goats requires the provision of 250g/kg roughage to ensure adequate energy intake and animal health. When feeding whole grain wheat, managers must adequately protect goats against acidosis, enterotoxaemia and Vitamin E deficiency. [Copyright &y& Elsevier]