Twenty two primiparous and 26 multiparous Holstein cows were distributed in three treatments in a completely randomized design. Diets were prepared to have 55:45 (RCS) and 75:25 (RCSH) forage to concentrate ratio, for normal corn silage, and 75:25 (BMR) for another diet based on the bm3 corn hybrid silage. No interaction was observed between treatment and parity. Alfalfa silage to corn silage ratio were 47.7:53.3 in the forage portion of the diets. Dry matter and crude protein intakes (kg/day)were higher for BMR and RCS (19.5 and 19.5; 3.41 and 3.42, respectively), as compared to the intakes for RCSH (17.6 and 3.14, respectively), while neutral detergent fiber had higher ingestion with BMR treatment (6.61) and lower with RCSH and RCS treatments (6.08 and 5.40, respectively). Acid detergent fiber was highly consumed (kg/day) for BMR and RCSH treatments (4.88 and 4.73, respectively). Milk production was higher for the treatment with high levels of concentrates (35.7kg/cow/day), followed by the BMR treatment (34.1kg/cow/day)and finally, by RCSH with lower production response (32.1kg/cow/day). Fat test in the milk was higher for high forage diets, while milk protein content followed the opposite pattern. Hybrid bm3, used in high forage diets, was efficient to maintain performance of high producing dairy cows, when compared to diets with normal or high forage diets based on different corn genetics.
corn silage; hybrids; bm3; high forage; milk; dairy cow
