Abstract:
The aim of the study was to evaluate the influence of the milking phase on somatic cell count (SCC) in milk obtained from the cisternal and alveolar parts of udders of selected Polish Holstein-Friesian cows. The study also assessed the impact of other genetic and environmental factors on SCC variability in cisternal and alveolar milk, including: the individual cow, lactation stage, age of cow, production level, milking speed, fat-to-protein ratio, and milking type. The research included 15 cows of Polish Holstein-Friesian breed at different ages, lactation stages, and with varying daily milk yield. A total of 210 milk observations were conducted, including 105 for 1 min milking and 105 for 8 min milking. The results obtained in the study indicated that milk obtained during two different milking phases exhibited similar SCC levels (F for LOGSCC = 0.79). The average actual SCC in milk produced by 15 cows in 105 observations for 1 min milking was 219,000 cells/mL, while for 8 min milking it was 229,000 cells/mL. The results were inconclusive, suggesting that SCC in cisternal and alveolar milk must be influenced by factors other than the milking phase. The analysis of variance conducted for this purpose provided the basis for stating a highly statistically significant effect of the individual cow (F for LOGSCC = 147.9), lactation stage (F for LOGSCC = 54.64), age of cow (F for LOGSCC = 12.39), daily production level (F for LOGSCC = 34.49), milking speed (F for LOGSCC = 17.56), and fat-to-protein ratio (F for LOGSCC = 22.99) on the variability of characteristics defining SCC in milk. In summary, SCC is characterized by high variability, influenced by a range of environmental and genetic factors such as the individual cow, lactation stage, age of cow, milking speed, and dietary fat-to-protein ratio. The influence of milking phase (1 min or 8 min) and milking type (morning or evening) should be considered inconclusive based on the entire population studied. For half of the cows, SCC in cisternal milk was higher than in alveolar milk, while for the other half, the situation was reversed. Further observations are required to confirm the hypothesis regarding the extent to which cows\' immunological response to bacterial infections is concentrated in the cisternal or alveolar part of the udder under national environmental conditions.
摘要:
该研究的目的是评估挤奶期对从选定的波兰荷斯坦-弗里斯奶牛乳房的胸骨和肺泡部分获得的牛奶中体细胞计数(SCC)的影响。该研究还评估了其他遗传和环境因素对池和肺泡乳中SCC变异性的影响,包括:个体牛,哺乳期,牛的年龄,生产水平,挤奶速度,脂肪与蛋白质的比例,和挤奶类型。这项研究包括15头不同年龄的波兰荷斯坦-弗里斯犬母牛,哺乳期,每天的牛奶产量也在变化。总共进行了210次牛奶观察,包括1分钟挤奶105和8分钟挤奶105。研究中获得的结果表明,在两个不同的挤奶阶段获得的牛奶表现出相似的SCC水平(LOGSCC的F=0.79)。在105个观察中,15头奶牛挤奶1分钟的牛奶中的平均实际SCC为219,000个细胞/mL,而挤奶8分钟是229,000个细胞/mL。结果尚无定论,这表明胸腔和肺泡乳中的SCC必须受到挤奶期以外的其他因素的影响。为此目的进行的方差分析为说明单个母牛的高度统计显着影响提供了基础(LOGSCC的F=147.9),泌乳期(LOGSCC的F=54.64),奶牛的年龄(LOGSCC的F=12.39),日产量水平(LOGSCC的F=34.49),挤奶速度(LOGSCC的F=17.56),和脂肪蛋白质比(LOGSCC的F=22.99)对定义牛奶中SCC的特征的变异性。总之,SCC的特点是高变异性,受一系列环境和遗传因素的影响,如个体奶牛,哺乳期,牛的年龄,挤奶速度,和膳食脂肪与蛋白质的比例。挤奶阶段(1分钟或8分钟)和挤奶类型(早晨或晚上)的影响应根据所研究的整个人群被认为是不确定的。对于一半的奶牛来说,胸腔乳中的SCC高于肺泡乳中的SCC,而对于另一半,形势逆转了。在国家环境条件下,奶牛对细菌感染的免疫反应集中在乳房的水箱或肺泡部分的程度,需要进一步的观察来证实这一假设。