为了研究复合益生菌菌液对奶牛产奶量、乳品质量、牛群健康和肠道菌群的影响，选择20头条件相近的健康奶牛随机分为试验组和对照组，采用菌液与饲料混合的方法饲喂牛群，考察其对奶牛产奶量，肠道菌群乳品质量和牛群健康的影响。结果表明，食用复合益生菌液的每头牛比对照组平均每天可以多产2.9 kg牛奶，提高产奶量14.8%，差异极显著 （P<0.01 ），经济效益显著；复合益生菌菌液可以促进肠道菌群调整，使有益菌主要是乳酸菌成为优势菌群，并可以抑制霉菌和降解霉菌毒素，降低牛乳中体细胞数，预防隐性乳腺（房）炎。

To study the effect of Probiotic Complex on the milk yield, milk quality, physical condition and intestinal flora of dairy cow, twenty Holstein cows with substantially the same age, birth parity, lactation month and milk yield were selected and divided into test group and control group. The test group was fed with fodder mixed with probiotic complex, and its effect on intestinal flora of dairy cow was examined through plate count and PCRDGGE. Califomia Mastitis Test (CMT) was conducted to investigate its effect on milk quality and physical condition of cows. Results showed that the cows fed with Probiotic Complex could produce 2.9 kg more milk than the control group, milk yield rose by 14.8%, the difference was significant (P<0.01) and this will make significant economic benefits. Probiotic Complex may help intestinal flora to adjust so that the beneficial bacteria mainly Lactobacillus become dominant. Furthermore, it will inhibit mildew and degrade mycotoxins, reduce the number of somatic cells in milk, and prevent recessive breast (room) inflammation.