The Use of Home-Produced Palm Oil to Replace Concentrate Feed in the Diet of Partially-Suckled Tropical Cows

摘要

Dual purpose tropical dairy cows that are both milked and suckle calves are often fed imported concentrate feed as a nutritional supplement. Palm oil (Elaeis guineensis L. Jacq.) is a home-produced, sustainable alternative to concentrate feed, and anexperiment was, therefore, conducted for 120 days to examine the effects of this substitution on digestion and cow production and reproduction. The cows' daily concentrate ration of 3.5 kg (supplying 20 MJ Gross Energy) was replaced by either 250 g or 500 g palm oil (supplying 10 or 20 MJ Gross Energy, respectively), to which calcium was added to protect it from rumen degradation. The milk yield of the cows was reduced by the low but not the high level of palm oil, compared with the concentrate treatment. There was no effect of replacing concentrate with palm oil on the amount of milk provided by the cows for their calves or on the milk composition. However, cows fed the palm oil lost more weight and condition than those fed concentrates in the first six weeks of the experiment. This weight loss was particularly severe at the low level of substitution, and cows fed this level had a delayed interval to conception and required more inseminations per conception compared to the other two treatments. Therewas no effect of feeding the palm oil on the rate of feed degradation in the rumen, but at both the low and high level, rumen pH was elevated for four hours after it was fed. It is concluded that calcium-saponified palm oil can be used to replace concentrate food for tropical cows at a rate of 0.14 g palm oil per kg concentrate, with only small losses in cow production. If less palm oil is provided per unit concentrate, milk production is likely to be considerably reduced and reproductive performance adversely affected.