Hertl Julia A, Schukken Ynte H, Tauer Loren W, Welcome Francis L, Gröhn Yrjö T
Section of Epidemiology, Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853.
Royal GD, 7418 EZ Deventer, the Netherlands.
JDS Commun. 2023 Apr 20;4(4):288-292. doi: 10.3168/jdsc.2022-0354. eCollection 2023 Jul.
The objective of this observational study was to estimate effects of clinical mastitis (CM) cases caused by different pathogens ( spp., , spp., , spp., and CM cases with no growth) occurring in the first 100 d in lactation 1, of a dairy cow on the future rate of occurrence of different types of CM during a cow's full lifetime. The outcomes were occurrence of spp., , spp., , spp., and CM cases with no growth, after the first 100 d of lactation 1, until a cow's removal through death or sale in that or a subsequent lactation. Data, including information on CM cases, milk production, and event dates (including death or sale dates), were collected from 14,440 cows in 5 New York State Holstein herds from January 2004 until February 2014. Generalized linear mixed models with a Poisson distribution and log link function were fit for each pathogen. The individual cow was the unit of analysis. was a predictor of future occurrence of , spp., and CM cases with no growth. Early-occurring spp. was a predictor of future cases of spp. Cases with no growth were predictors of future occurrence of spp., , spp., and cases with no growth. Thus, and cases with no growth occurring early in lactation 1 appear to be consistent risk factors for future cases of CM, whether cases with the same pathogen or a different pathogen. In this study, farm effects on later pathogen occurrence differed somewhat, so treatment protocol and culling strategy may play a role in the findings. Nevertheless, the findings may help farmers in managing young cows with CM in early productive life, especially those with or cases with no growth, in that they may be more susceptible to future CM cases in their later productive life, thus meriting closer attention.
本观察性研究的目的是评估奶牛泌乳期第1个100天内由不同病原体（无乳链球菌、停乳链球菌、金黄色葡萄球菌以及无细菌生长的临床型乳房炎病例）引起的临床型乳房炎（CM）病例对奶牛整个生命周期内不同类型CM未来发生率的影响。观察结果为泌乳期第1个100天后直至奶牛因死亡或出售（在该泌乳期或随后的泌乳期）而被淘汰期间，无乳链球菌、停乳链球菌、金黄色葡萄球菌以及无细菌生长的临床型乳房炎病例的发生情况。从2004年1月至2014年2月，收集了纽约州5个荷斯坦奶牛场14440头奶牛的数据，包括CM病例信息、产奶量以及事件日期（包括死亡或出售日期）。针对每种病原体，拟合了具有泊松分布和对数链接函数的广义线性混合模型。以个体奶牛作为分析单位。无乳链球菌是未来无乳链球菌、停乳链球菌以及无细菌生长的临床型乳房炎病例发生的预测因素。早期发生的停乳链球菌是未来金黄色葡萄球菌病例的预测因素。无细菌生长的病例是未来无乳链球菌、停乳链球菌、金黄色葡萄球菌以及无细菌生长的病例发生的预测因素。因此，泌乳期第1个100天早期出现的无乳链球菌和无细菌生长的病例似乎是未来CM病例的一致风险因素，无论病例是否由相同病原体或不同病原体引起。在本研究中，农场因素对后期病原体发生的影响略有不同，因此治疗方案和淘汰策略可能对研究结果有影响。尽管如此，这些研究结果可能有助于奶农在奶牛生产早期管理患有CM的年轻奶牛，特别是那些患有无乳链球菌或无细菌生长的病例，因为它们在后期生产生活中可能更容易发生未来的CM病例，因此值得密切关注。
