Department of Veterinary Clinical Medicine, University of Illinois Urbana-Champaign, Champaign, IL, USA.
Department of Microbiology and Immunology, Institute of Biosciences, São Paulo State University, Botucatu, Brazil, USA.
Sci Rep. 2017 Aug 14;7(1):8067. doi: 10.1038/s41598-017-08790-5.
Preventive infusion of antibiotics in the mammary gland of cows consumes 11 tons/year of medically relevant antimicrobials, yet, this practice might not be critical to prevent new infections in the healthy mammary gland of cows. Here, we used next-generation sequencing and quantitative real-time PCR to determine the impact of dry cow therapy without antibiotics on milk microbiome and bacterial load, respectively. Cows diagnosed as negative for mastitis at dry off were randomly allocated to receive antibiotic (intramammary ceftiofur hydrochloride) and teat sealant or just teat sealant. Firmicutes was the most abundant phylum, and Corynebacterium, Acinetobacter, and Staphylococcus, often involved in mastitis cases, were the most abundant genera across treatments and time. However, there were no effects of antimicrobial on milk microbiome and bacterial load. Bacterial load was greater at seven days postpartum than at dry off. Dry cow therapy based on teat sealant without antibiotics can be used with no detrimental impacts on milk microbiome and bacterial load in cows with a healthy mammary gland.
预防奶牛乳腺灌注抗生素每年消耗 11 吨具有医学相关性的抗菌药物，但这一做法对于预防健康奶牛乳腺的新感染可能并非关键。在这里，我们使用下一代测序和定量实时 PCR 分别确定了不使用抗生素的干奶疗法对牛奶微生物组和细菌负荷的影响。在干奶时被诊断为乳腺炎阴性的奶牛被随机分配接受抗生素（乳房内盐酸头孢噻呋）和乳头封闭剂或仅乳头封闭剂。厚壁菌门是最丰富的门，而经常与乳腺炎病例相关的棒状杆菌属、不动杆菌属和葡萄球菌属是所有处理和时间中最丰富的属。然而，抗菌药物对牛奶微生物组和细菌负荷没有影响。产后 7 天的细菌负荷高于干奶时。基于不使用抗生素的乳头封闭剂的干奶疗法可用于具有健康乳腺的奶牛，而不会对牛奶微生物组和细菌负荷产生不利影响。
