The experiment was conducted to evaluate the performance of lactating Holstein cows fed diet with different replacement levels (0, 12, 24 and 36%) of forage cactus (Opuntia ficus indica Mill) for sorghum silage (Sorghum bicolor (L.) Moench). Eight cows were assigned to a two 4x4 latin square design. Each experimental period lasted 21 days, 14 days for adaptation and 7 days for data collection. The intakes of dry matter (DM) in kg/day, % of live weight (LW) and g/kg0,75, organic matter and total carbohydrates in kg/day, were not affected by the forage cactus levels (20.18, 3.41, 167.80, 18.86, and 14.85, respectively). The nonfiber carbohydrates (kg/day) intake increased and the intakes of neutral detergent fiber (kg/day and % of LW), acid detergent fiber, crude protein and ether extract (kg/day) linearly decreased as the forage cactus levels increased. The sodium intake was not affected by the inclusion of forage cactus, with average value of 29.45g/day. The potassium and magnesium intake increased and phosphorus intake linearly decreased. The milk production and fat corrected milk was not affected by the forage cactus levels (25.01 and 26.97 kg/day, respectively). There was a quadratic effect of levels of forage cactus on the milk fat concentration, with maximum milk fat of 4.08% with 20.51% of forage cactus. Feed:milk production ratio linearly decreased as the forage cactus levels increased.
forage cactus; intake; milk production; sorghum silage
