Molasses and urea in the feeding of dairy cows during the dry season

Abstract

A mixture of 90% molasses and 10% urea was fed during the winter dry season to supplement mature pasture as feed for crossbred dairy cows. Twelve cows, in 6 sequences, were used in an 84 day "Switchback-type" trial. Three treatments were tested: I) A mixture of molasses and urea furnishing approximately two-thirds of the protein nitrogen needed by the cows, II) the same mixture furnishing one-third of the nitrogen needed (the remaining two-thirds was supplied by a concentrate mixture), III) the needed protein nitrogen furnished by concentrates. The resulting average daily milk production (4% FCM) was: Treatment I - 8.42 kg, Treatment II - 8.91 kg, Treatment III - 9.09 kg. The difference between treatments I and III was significant (P<0.05). There was no significant difference in fat content. Considering only feed and milk prices in August of 1968, the best return was obtained by treatment II (NCr$ 2,00 per cow/day). Treatment III yielded (NCr$ 1,95) and treatment I (NCr$ 1,92). Cows in all treatments registered slight gains in weight. No harmful effects were observed in any of the animals.