Author : Adiarto

Summary : Responses of lactating cows to varying levels of concentrate supplementation to rice straw were studied using 16 Holstein-friesian cows arranged in randomized complete block (RCB) design with four treatments. The study was conducted at Baturraden Breeding Center, Purwokerto, Indonesia for 120 days. Concentrate supplement containing 18-20 percent crude protein (CP) and 60-70 percent total digestible nutrient (TDN) was given to the animals based on their milk production at the ratio of 1:1 (kg of concentrate to kg of milk) for treatment I, 1:1.5 for treatment II, and 1:2 for treatment III. Rice straw-Molasses-Water Mixture (RSMW) was fed ad libitum. Animals under treatment IV, which served as control, were given concentrate and napier grass following the usual feeding management of Baturraden Breeding Center. Animals under treatment I consumed significantly (P<0.05) more dry matter (19.01 kg/day) than those under treatment II (15.52 kg/day), treatment III (14.17) kg/day) and treatment IV (11.71 kg/day). Likewise, the animals under treatment I had significantly (P<0.05) higher intakes of CP and TDN intakes of treatments I - IV were 2.50 kg and 11.13 kg, 1.65 kg and 8.40 kg, 1.19 kg and 7.10 kg, and 1.30 kg and 7.60 kg, respectively. Although milk production of the animals under treatment I was the highest among the four treatments, daily milk production and total milk production of treatment I were only significantly different from those under treatment III. While fat and protein contents of milk produced by the cows under treatments I and IV were similar, their values were significantly lower than those under treatments III and II (except with milk protein content in treatment II). Income over feed cost of treatment I was the highest among the four treatments but although it was not significantly different from that of treatments II and IV. Results indicated that rice straw can be used as the sole roughage source for dairy cows provided that concentrate supplement with high protein (18-20 percent CP) and...