The responses of lactating dairy cows to feeding of high molasses levels

Abstract

Molasses has been fed to dairy cows for about a century. Extensive studies have shown that its energy value is worth from 75 to 100% that of maize when up to 10% of molasses is fed in a complete diet and high molasses inclusion in the diet can be detrimental to the responses of the animals. Nevertheless, the maximum inclusion rate of molasses in a diet that cows can tolerate has still been unclear. Few publications are available to describle the responses of cows to very high molasses feeding. This is a question, however, that both farmers and advisers are concious of. The present experiment was designed to evaluate the effects on milk yield and composition, feed intake, liveweight gain and health of lactating cows fed on very high levels of molasses, in comparision with those fed a relatively low level.Fifteen British Friesian late lactation cows (168 ± 6 days calved) all in second lactation or more were randomly allocated to a 3 x 3 changeover experiment with 21 day periods. The cattle were fed individually through Broadbent Calan Gates ad libitum on a complete diet of silage plus a liquid supplement including molaferm 20 (a mixture of 80% cane molasses with 20% condensed molasses solubles supplied by United Molasses Ltd.), soyabean meal and fish meal.