Effects of different concentrate levels in the diet and gender on weight gain of F1 crossbred cattle (BBB × Zebu cross) from 7 to 24 months of age in Tra Vinh
The experiment was conducted to determine the effects of different concentrate levels in the diet and gender on the weight gain performance of F1 crossbred cattle (BBB × Zebu cross) during the 7–24 month growth phase. The study was arranged in a completely randomized 2-factor design, including the effects of three diets with different concentrate-to-roughage ratios (30%, 40%, and 50%) and gender (12 heifers, 12 bulls, and 12 castrated bulls) on weight gain. A total of nine treatments were applied, with four replicates per treatment. The results indicated that both diet and gender significantly affected the average daily gain (ADG) of F1 crossbred cattle. The diet with a 50% concentrate-to-roughage ratio resulted in the highest weight gain, and bulls exhibited higher ADG (0.72 – 1.04 kg/head/day) compared to castrated bulls (0.70 - 1.00 kg/head/day) and heifers (0.61–0.90 kg/head/day). Cattle fed diets with a 50% concentrate ratio had lower average feed conversion ratios compared to those fed diets with a 30% ratio. Bulls had the lowest feed conversion (10.20 kg DM/kg weight gain), while heifers had the highest (10.99 kg DM/kg weight gain). Economic analysis showed that F1 bulls (BBB × Zebu cross) provided the highest monthly profit (592,991 VND/month), and the 50% concentrate ratio diet offered the best economic efficiency (563,639 VND/month). The interaction between diet and gender was also significant, with bulls on a 50% concentrate diet achieving the highest profit (634,425 VND/month). Conversely, heifers had the lowest profit, particularly when fed a 30% concentrate diet (438,045 VND/month).
