nutrient consumption and digestibility of sugar cane diets supplemented with soybean meal or urea

The present work was developed aiming to verify the effect on intake and digestibility of diets based on sugar cane, whose CP levels were supplemented with concentrate based on soybean meal or different levels of urea, fed to dairy cows. Twelve Holstein dairy cows were used, arranged in three 4 x 4 Latin squares distributed according to the lactation period. After analysing the variance, we proceeded to compare the non-orthogonal contrasts. There was no difference (P>0.05) for the consumption of dry matter/material (DM), organic matter (OM), crude protein (CP), ether extract (EE), total carbohydrates (CHO), non-fibrous carbohydrates (NFC), neutral detergent fiber (NDF), and DM (g/kg 0.75) between diets. Between different levels of urea, a linearly decreasing effect for the consumption of NDF kg/day and NDF (% body weight) was verified. There was no difference (P>0.05) for apparent digestibility coefficients of DM, OM, CP, EE, NDF, and NFC when comparing different diets. There was linear increase between treatments of urea for CHO digestibility and total nutrient digestive. The soybean meal in the concentrate is not necessary in diets based on sugarcane supplemented with urea. The inclusion of urea is not necessary in diets based on sugar cane supplemented with a base concentrate of soybean meal for dairy cows producing 20 kg/day.