Institute of Veterinary Public Health, University of Veterinary Medicine, 1210, Vienna, Austria.
Data, Statistics and Risk Assessment, Austrian Agency for Health and Food Safety (AGES), 8010, Graz, Austria.
J Dairy Sci. 2019 May;102(5):4452-4463. doi: 10.3168/jds.2018-15657. Epub 2019 Mar 7.
Bovine mastitis is the most frequently reported disease among dairy cows worldwide. Treatment of udder disease often involves the use of antimicrobial substances, which is difficult to justify with respect to their possible effect on the development and spread of antimicrobial resistance. Prevention of udder disease is therefore always preferable to treatment. The study presented here statistically analyzed the probability of mastitis occurring during 3,049 lactation periods on 208 farms and attempted to ascertain which on-farm management factors contributed to the occurrence of this udder disease in Austria. Farm management was assessed via online surveys completed by 211 farmers (211/251; response rate = 84.1%) as well as national milk performance recorders observing milking technique and herd veterinarians evaluating farm hygiene levels. Veterinary treatment records were used as a basis for mastitis reporting. The analysis was carried out using a generalized linear mixed model. The study population was not randomized but was part of a larger observational study. More than three fourths of the study farms were run conventionally, and the remainder were organic. Freestalls (and straw yards) made up 66% of the study population, and 34% of farms had tiestalls. Herd size ranged from 8 to 94 dairy cows (mean = 26.9; median = 21), with the most common breed (74% of all cows) being dual-purpose Simmental (Austrian Fleckvieh). A mastitis risk of 14.4% was reported via veterinary treatment records. The following factors were shown to be associated with a reduction in the risk of mastitis occurring: regular access to pasture (odds ratio, OR = 0.73), automatic milking machine shut-off (OR 0.67), and access to feed immediately after milking (OR = 0.43). Detrimental effects, which were likely to increase the probability of mastitis occurring, included lactation number (OR = 1.18), farming part time (OR = 1.55), and udders on the farm being classed by herd veterinarians as medium to severely soiled (OR = 1.47). The study presented here was able to confirm several management factors recommended to reduce the probability of mastitis occurring during a cow's lactation period, with particular relevance for the small dairy herds common to Austria.
奶牛乳腺炎是全世界奶牛中最常报告的疾病。乳房疾病的治疗通常涉及使用抗菌物质，但就其对抗菌药物耐药性的发展和传播的可能影响而言，这种做法很难证明是合理的。因此，预防乳房疾病始终优于治疗。本研究通过对 208 个农场的 3049 个泌乳期进行统计分析，试图确定奥地利农场管理因素中哪些与这种乳房疾病的发生有关。农场管理通过 211 名农民（211/251；回应率=84.1%）在线调查以及观察挤奶技术的国家牛奶性能记录器和评估农场卫生水平的兽医进行评估。使用兽医治疗记录作为乳腺炎报告的依据。分析采用广义线性混合模型进行。研究人群不是随机的，但属于更大规模的观察性研究的一部分。超过四分之三的研究农场采用传统方式经营，其余农场采用有机方式。自由卧床（和草垫场）占研究人群的 66%，34%的农场采用系留卧床。畜群规模从 8 头到 94 头奶牛不等（平均值=26.9；中位数=21），最常见的品种（所有奶牛的 74%）是乳肉兼用西门塔尔牛（奥地利弗莱克维赫牛）。通过兽医治疗记录报告乳腺炎风险为 14.4%。以下因素与降低乳腺炎发生风险相关：定期放牧（优势比，OR=0.73）、自动挤奶机关闭（OR=0.67）和挤奶后立即进食（OR=0.43）。可能增加乳腺炎发生概率的不利因素包括泌乳次数（OR=1.18）、兼职养殖（OR=1.55）和农场兽医认为牛只乳房中等至严重污染（OR=1.47）。本研究能够证实一些管理因素，这些因素被推荐用于降低奶牛泌乳期乳腺炎发生的概率，对于奥地利常见的小型奶牛场尤其相关。
