This study was conducted to evaluate replacement of ground corn grain with cassava scrapings on nutrient intake, digestibility, and production of primiparous Holstein lactating dairy cows receivind diets containing forage cactus (Opuntia ficus indica, Mill), sorghum silage and concentrate. Five cows averaging 60±15 of days in milk and initial body weight (BW) of 448 kg were randomly assigned to a 5 × 5 Latin square with increasing levels of cassava scrapings in the diet: 0, 25, 50, 75 or 100%. Intakes of dry matter (DM) (kg, %BW and g/BW kg0.75), organic matter (OM), crude protein (CP), ether extract (EE), nonfiber carbohidrates (NFC), total carbohydrates (TCHO), acid detergent fiber (ADF), neutral detergent fiber (NDF), and total digestible nutrients (TDN) all were not affected by replacing ground corn with cassava scrapings in the diet. Similarly, increasing the dietary levels of cassava scrapings did not affect apparent digestibilities of nutrients (P>0.05). However, milk yield, milk yield corrected for 3.5% fat, and fat yield decreased linearly by 20, 30 and, 1.15 g/day, respectively, when corn grain was replaced with cassava scrapings. Feed efficiency, expressed as kg of 3.5% fat corrected milk per kg of DM, also decreased linearly by 0.001 per each unit of cassava scrapings added to the diet. No significant differences for milk fat content were observed among treatments in this trial.
digestibility; fat yield; intake; feed efficiency; milk yield
