Multiple supplements containing spineless cactus enriched with urea forcattle

ABSTRACT. This study was realized to evaluate the effect of the ‘multiple supplements’ containing spineless cactus enriched with urea (0, 1, 2 and 3% on dry matter basis - DM) as a replacement to a traditional supplement (control) on ruminal parameters and microbial protein synthesis in crossbred steers. Five steers(½ Holstein x Zebu) can nulated in the rumen, with an average initial body weight of 240 ± 22.1 kg were used in a 5 × 5 Latin square. A quadratic effect was observed for DM intake and N retention, with maximum values of 6.97 kg d-1 and 50.9 gd-1 with the inclusion of 1.8 and 2.1% urea, respectively. Maximum concentrations of 16.2, 23.2 and 24.3 mg dL-1of N-NH3were recorded in animals fed spineless cactus enriched with 1, 2, and 3% of urea. There was a quadratic effect on ruminal pH, with a value of 6.45 at 4.08 hours after feeding. Microbial synthesis efficiency of 103 g CPkg-1 TDN was obtained with the inclusion of 1.6% urea. Multiple supplements containing spineless cactus enriched with 1.6 up to 1.8% urea in replacement of a traditional supplement is recommended for cattle.