Goldsmith Katelyn, Lefler Josh, Embree Mallory, VandeHaar Michael J
Department of Animal Science, Michigan State University, East Lansing 48824.
Native Microbials Inc., San Diego, CA 92121.
JDS Commun. 2022 Oct 28;4(1):31-34. doi: 10.3168/jdsc.2022-0250. eCollection 2023 Jan.
We evaluated the effects of 2 direct-fed microbial (DFM) supplements containing 4 native rumen microorganisms on the production of dairy cows. Ninety Holstein cows (43% primiparous) were fed a common diet. Mean days in milk, milk yield, and body weight at the beginning of the study (mean ± standard deviation) were 92 ± 23 d, 45 ± 10 kg/d, and 659 ± 86 kg, respectively. After 14 d, they were blocked by parity, days in milk, and energy-corrected milk (ECM) per unit of metabolic body weight. Within block, cows were randomly assigned to treatments, which were top-dressed daily for the next 112 d. Treatments were 150 g of ground corn mixed with (1) no live DFM (CON), (2) 5 g of a live DFM (Galaxis 2.0; G2), and (3) 5 g of a live DFM (Galaxis 2.0 Plus; G2P). G2 and G2P were products of Native Microbials Inc. (San Diego, CA) and contained the same organisms but in different concentrations. Supplementation with DFM did not alter yield of total milk, protein, or fat, but slightly decreased body weight gain and body condition score gain with no difference between G2 and G2P. The DFM tended to decrease dry matter intake (DMI) and tended to improve ECM/DMI. The DFM did not alter digestibility of fiber, starch, or protein and did not alter concentrations of glucose or nonesterified fatty acids, but tended to decrease concentration of insulin in plasma. Direct-fed microbials decreased somatic cell counts in milk with no difference between G2 and G2P. In conclusion, supplementation with native DFM had little impact on animal production and efficiency.
我们评估了两种含有4种天然瘤胃微生物的直接投喂微生物（DFM）补充剂对奶牛生产性能的影响。90头荷斯坦奶牛（43%为初产牛）饲喂相同的日粮。研究开始时的平均泌乳天数、产奶量和体重（平均值±标准差）分别为92±23天、45±10千克/天和659±86千克。14天后，根据胎次、泌乳天数和每单位代谢体重的能量校正乳（ECM）进行分组。在每组内，奶牛被随机分配到不同处理组，并在接下来的112天里每天进行顶部添加。处理组分别为：150克磨碎的玉米与（1）不添加活的DFM（对照组，CON）、（2）5克活的DFM（Galaxis 2.0；G2）和（3）5克活的DFM（Galaxis 2.0 Plus；G2P）混合。G2和G2P是Native Microbials Inc.（加利福尼亚州圣地亚哥）的产品，含有相同的微生物，但浓度不同。添加DFM并未改变总奶量、蛋白质或脂肪的产量，但略微降低了体重增加和体况评分增加，G2和G2P之间无差异。DFM有降低干物质采食量（DMI）的趋势，并有提高ECM/DMI的趋势。DFM未改变纤维、淀粉或蛋白质的消化率，也未改变葡萄糖或非酯化脂肪酸的浓度，但有降低血浆中胰岛素浓度的趋势。直接投喂微生物降低了牛奶中的体细胞数，G2和G2P之间无差异。总之，添加天然DFM对动物生产性能和效率影响不大。
