Use of direct fed microbial for mid lactation dairy cows

Abstract

Fifteen Holstein cows, with 156 ± 53 days in milk, average milk yield of 31.4 ± 0.5 kg/d and body weight of 665 ± 16 kg were used with the objective of evaluating the use of microbial additives in the diet. The experiment was arranged in a 3 x 3 Latin square design with five replications. The treatments were: DFM-B (Ruminobacter amylophilum, Ruminobacter succinogenes, Succinovibro dextrinsolvens, Bacillus cereus, Lactobacillus acidophilus, Ente-rococus faecium in calcium carbonate); DFM-BL (Bacteria and inert vehicle associated with 6x10 9 /g live cells and 2x10 8 / g dead cells of Sacharomyces cerevisiae) or Control-10g of calcium carbonate. The additives were supplied in capsules by forced ingestion twice a day. Supplementation of animals in the middle lactation with DFM-B or DFM-BL did not alter dry matter intake, milk production and composition, feed efficiency, body weight and body condition score. However, animals supplemented with DFM-B tended to have lower ruminal pH, lower alanine excretion, higher nitrogênio uréico no leite (MUN) and lower digestibility of dry matter. Animals supplemented with DFM-BL tended to have lower somatic cell count in milk and increased daily mastication time, suggesting that the associated supplementation of bacteria and yeasts has greater beneficial potential than the use of only bacteria.