Hurri E, Alvåsen K, Widgren S, Ohlson A, Aspán A, Pedersen K, Tråvén M
Department of Clinical Sciences, Swedish University of Agricultural Sciences, SE-750 07 Uppsala, Sweden; Department of Animal Health and Antimicrobial Strategies, Swedish Veterinary Agency (SVA), SE-751 89 Uppsala, Sweden.
Department of Clinical Sciences, Swedish University of Agricultural Sciences, SE-750 07 Uppsala, Sweden.
J Dairy Sci. 2025 Jan;108(1):845-855. doi: 10.3168/jds.2024-25304. Epub 2024 Oct 9.
Mycoplasma bovis is an important pathogen causing pneumonia, mastitis, and arthritis in cattle all over the world entailing reduced animal welfare and economic losses. In this longitudinal study, we investigated the presence of M. bovis antibodies in bulk tank milk (BTM) and in milk from primiparous (PP) cows at 4 sampling occasions over 2 yr. Herd characteristics associated with a positive antibody test result in PP cows were investigated. The participating dairy herds (n = 149) were situated in southern Sweden, samples were collected and analyzed with ID Screen antibody ELISA. Information on herd characteristics was retrieved from the national DHI database. To identify herd characteristics associated with the presence of antibodies in PP cows, mixed linear regression with herd and sample as random factors were used. The apparent herd-level prevalence of M. bovis infection based on antibodies in BTM was 17%, but with the addition of PP cows, the prevalence increased to 28%. The results showed that larger herds and introduction of cattle was associated with higher antibody levels in PP cows. In conclusion, this study showed a clear difference in the apparent prevalence of M. bovis infection based on antibodies in BTM or in PP cows: The number of positive herds was almost doubled when including PP cows. This motivates repeated sampling of a few PP cows to find newly infected herds in an early stage. Finally, the results showed that introduction of cattle influences the level of M. bovis antibodies. This is important in the control and prevention of further spread of the infection. It is essential for free herds to know their M. bovis status, and antibody testing is highly recommended if introducing cattle.
牛支原体是一种重要的病原体，可在全球范围内导致奶牛发生肺炎、乳腺炎和关节炎，从而降低动物福利并造成经济损失。在这项纵向研究中，我们在两年内的4个采样时间点调查了散装罐奶（BTM）和初产（PP）奶牛的牛奶中牛支原体抗体的存在情况。我们还调查了与PP奶牛抗体检测呈阳性结果相关的畜群特征。参与研究的奶牛场（n = 149）位于瑞典南部，采集样本并用ID Screen抗体ELISA进行分析。畜群特征信息从国家奶牛性能测定（DHI）数据库中获取。为了确定与PP奶牛抗体存在相关的畜群特征，我们使用了以畜群和样本为随机因素的混合线性回归分析。基于BTM中抗体的牛支原体感染的表观畜群水平患病率为17%，但加入PP奶牛后，患病率升至28%。结果表明，规模较大的畜群和引入牛只与PP奶牛中较高的抗体水平相关。总之，本研究表明基于BTM或PP奶牛中抗体的牛支原体感染表观患病率存在明显差异：纳入PP奶牛时，阳性畜群数量几乎翻倍。这促使对少数PP奶牛进行重复采样，以便在早期发现新感染的畜群。最后，结果表明引入牛只影响牛支原体抗体水平。这对于控制和预防感染的进一步传播很重要。对于无病畜群来说，了解其牛支原体状况至关重要，如果引入牛只，强烈建议进行抗体检测。
