Millward Sam, Mueller Karin, Smith Robert, Higgins Helen M
Oakhill Veterinary Centre, Preston, United Kingdom.
Department of Livestock Health and Welfare, Institute of Veterinary Science, University of Liverpool, Liverpool, United Kingdom.
Front Vet Sci. 2019 Dec 12;6:451. doi: 10.3389/fvets.2019.00451. eCollection 2019.
The aim of this study was to estimate the prevalence of macroscopic reproductive tract abnormalities in a sample of female cattle in the UK. To our knowledge, this type of post-mortem survey has not been conducted in the UK since the 1970s. Over the last 40 years significant changes have occurred with respect to management and genetics. Moreover, there have been changes in growth rates in beef animals, elevated milk yields and a decline in fertility in dairy cattle. It was hypothesised that differences may exist in the extent and type of lesions occurring compared with previous studies. Between May and July 2017, the reproductive tracts of cattle () were examined post-mortem at an abattoir in the north west of England. All female cattle slaughtered on visit days were eligible. In total 680 tracts were examined, constituting 88% of those eligible. Macroscopic abnormalities were recorded using a standard format and definitions. The majority of cattle were a dairy breed (73%) with Holstein-Friesian accounting for over half of these. Median age at slaughter for dairy breeds was 5.1 years (range 1.7-13.8 years) and 3.9 years (0.92-16.8 years) for beef breeds. A total of 141 out of the 680 reproductive tracts examined exhibited at least one lesion, giving an overall prevalence of abnormalities of 20.7%, with 95% confidence interval (CI) 17.9-23.9%. This is double the last similar UK-based study carried out in the late 1970s. There were 20 different types of abnormality identified, with 207 individual lesions in 141 abnormal tracts. The ovary was the most common anatomical location displaying abnormalities, accounting for 70.2% of all abnormal tracts. Ovaro-bursal adhesions were the most common abnormality found at 5.3% (CI 3.9-7.2%) and half of these were classified as severe. The second most common lesion was follicular cystic ovarian disease at 4.6% (CI 3.2-6.4%), followed by anoestrus at 4.1% (CI 2.9-5.9%). Double the prevalence of macroscopic reproductive tract lesions is a concern. Greater use of post-mortem material for disease surveillance and further studies into risk factors, especially for the most prevalent lesions, is warranted.
本研究的目的是估计英国母牛样本中宏观生殖道异常的患病率。据我们所知，自20世纪70年代以来，英国尚未进行过此类尸检调查。在过去40年里，管理和遗传学方面发生了重大变化。此外，肉牛的生长速度、奶牛的产奶量有所提高，而奶牛的繁殖力有所下降。据推测，与以前的研究相比，所发生病变的程度和类型可能存在差异。2017年5月至7月，在英格兰西北部的一家屠宰场对牛的生殖道进行了尸检。在访问日屠宰的所有母牛都符合条件。总共检查了680个生殖道，占符合条件者的88%。使用标准格式和定义记录宏观异常情况。大多数牛是奶牛品种（73%），其中荷斯坦-弗里生牛占一半以上。奶牛品种的屠宰中位年龄为5.1岁（范围1.7 - 13.8岁），肉牛品种为3.9岁（0.92 - 16.8岁）。在检查的680个生殖道中，共有141个至少出现了一处病变，总体异常患病率为20.7%，95%置信区间（CI）为17.9 - 23.9%。这是英国20世纪70年代末进行的上一次类似研究结果的两倍。共识别出20种不同类型的异常，141个异常生殖道中有207处个体病变。卵巢是显示异常的最常见解剖部位，占所有异常生殖道的70.2%。卵巢囊粘连是最常见的异常，占5.3%（CI 3.9 - 7.2%），其中一半被归类为严重粘连。第二常见的病变是卵泡囊肿性卵巢疾病，占4.6%（CI 3.2 - 6.4%），其次是发情期停止，占4.1%（CI 2.9 - 5.9%）。宏观生殖道病变患病率翻倍令人担忧。有必要更多地利用尸检材料进行疾病监测，并进一步研究风险因素，特别是针对最常见的病变。
