Abstract
Twelve local cows in an early lactation stage (2nd-3rd lactation) were assigned to 4 treatments having 3 animals in each group. All cows were offered rice straw ad libitum, 0.5 kg rice bran and 3 to 4 hours roadside grazing a day. Treatments were arranged in a 2 x 2 factorial design, in which 2 levels of urea-molasses-block (UMB) (0 and 400 OW) and 2 levels of green grass (0 and 2 kg/h/d) were considered as the factors. Total dry matter intake (D MI) and milk yield were higher (P‹ 0.05) in animals provided with U MB. UMB and green grass interacted significantly (P/0.05) to increase the total DM intake and milk yield. The most economical return was obtained with 400 g UMB with 2 kg green grass/11/d where the feed conversion was 2.93 (kg DivII/kg milk).
INTRODUCTION
Rice straw is the principal feed for cat-tle throughout the year in Bangladesh. But after the flood or drought there is an acute shortage of cattle feed or even of straw. in this situation, urea-molasses-block (U MI3) may be a valuable supplement to a straw based ration. The UMB supplies energy, ni-trogen and minerals to the animals and thus improves condition of rumen microbes to ferment the ingested feed and provide mi-crobial protein. It also supplies some bypass nutrients to the animals (An-lanai and Mirza, 1986). Soetanto (1987) indicated the poten-tiality of UMB as a supplement for cattle in straw based diets. The present experiment was conducted to study the effect of UMB during scarcity period on the milk produc-tion performance of local cows in village condition.
MATERIALS AND METHODS
The feeding trial was carried out from December, 1988 to February, 1989 after the devastating flood of 1988 in Gokulnagar, a village 2 km north west to Bangladesh Live-stock Research Institute BL 1), Savar, Dhaka. Twelve local cows at an early lacta-tion stage (2nd-3rd lactation) having 144-1_.1.2 kg body weight were assigned to 4 treat-ments with 3 animals in each group were offered ad libitum rice straw, 0.5 kg rice bran and 3 to 4 hours grazing.
The composition of UMB is presented in Tat* 1. The feeding period lasted for 60 days alter an adjustment period of 15 days. Data on feed intake and milk production were recorded daily. Animals were weighed initially,
The DM and CP content of UMB were 85.5 and 19.8%, whereas DM and CP of rice straw and green grass were 88.6, 2.9 and 198 and 6.4% respectively.
