Twenty-five crossbred Holstein-Zebu cows was used to evaluate the effect of body condition score at calving on milk yield and composition and evaluate the body reserves mobilization by variation of body condition score during the first 120 days of lactation. The cows were allocated in two classes according to the body condition score at calving (BCSC), using a scale from 1 (very thin) to 5 (very fat): class 1, cows with of BCSC > 3.25; and class 2, cows with BCSC <3.25. As expected the two classes of BCSC were significantly different at calving, showing mean values of 3.71 and 2.58 for class 1 and 2, respectively. From calving to 120 days of lactation cows of class 1 showed greater change in body condition score (CBCS) than cows of class 2 with mean cows, showed values of -0,57 and -,12 units of BCS for class 1 and 2, respectively. The body condition score at calving did not influence milk yield, but milk yield adjusted to 3.5% fat, fat percentage and production were different between cows of class 1 and 2. The crossbred cows Holstein-Zebu with a BCSC greater to 3.0 showed higher milk yield corrected to 3.5% fat and yield fat in this study.
body reserve mobilization; body score; crossbred dairy cows; milk composition and yield
