Rahimi M R, Khoramian B, Drillich M, Azizzadeh M
Graduated from Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran.
Department of Clinical Sciences, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran.
Iran J Vet Res. 2021 Fall;22(4):326-330. doi: 10.22099/IJVR.2021.40046.5805.
The somatic cell count (SCC) of individual cow samples is a useful proxy for monitoring udder health status.
The present study aimed to provide updated information about udder health in Iranian Holstein dairy cattle, and to quantify the effectiveness of the mastitis control program.
A total of 17,990 monthly test-day records from 1,663 Holstein dairy cattle in 10 "regular" herds and 2,389 test-day records from 386 Holstein dairy cattle in 2 herds that were assigned to the 10-point mastitis control program ("controlled" herds) were included. Each test-day record comprised the date of recording, daily milk production (kg), fat and protein (%), days in milk, parity, and SCC.
Median (Q1-Q3) SCC × 10 for "regular" and "controlled" herds were 136 (52-391) and 64 (24-204) cells/ml, respectively. Also, the percentage of records containing SCC >200,000 cells/ml (elevated SCC) for these groups were 40.3% and 25.5%, respectively. Mixed effects logistic analysis revealed that milk records from cows in the first lactation, early lactation, and with >40 kg daily milk yield had lower odds of elevated SCC. The odds of elevated SCC were lower in summer and autumn than in winter.
Host and environmental characteristics influence SCC. This should be considered for the interpretation of SCC results. Mastitis control programs can support dairy producers to reach a standard level of udder health.
个体奶牛样本的体细胞计数（SCC）是监测乳房健康状况的有用指标。
本研究旨在提供有关伊朗荷斯坦奶牛乳房健康的最新信息，并量化乳腺炎控制计划的有效性。
纳入了来自10个“常规”牛群的1663头荷斯坦奶牛的17990条月度测定日记录，以及来自2个实施10分制乳腺炎控制计划牛群（“受控”牛群）的386头荷斯坦奶牛的2389条测定日记录。每条测定日记录包括记录日期、日产奶量（千克）、脂肪和蛋白质含量（%）、泌乳天数、胎次和体细胞计数。
“常规”和“受控”牛群体细胞计数×10的中位数（四分位数间距）分别为136（52 - 391）和64（24 - 204）个/毫升。此外，这些组中体细胞计数>200,000个/毫升（体细胞计数升高）的记录百分比分别为40.3%和25.5%。混合效应逻辑分析显示，头胎泌乳期、泌乳早期且日产奶量>40千克的奶牛的牛奶记录中体细胞计数升高的几率较低。体细胞计数升高的几率在夏季和秋季低于冬季。
宿主和环境特征会影响体细胞计数。在解释体细胞计数结果时应考虑这一点。乳腺炎控制计划可以帮助奶农达到乳房健康的标准水平。
