Gonzalo C, Carriedo J A, Beneitez E, Juárez M T, De La Fuente L F, San Primitivo F
Departamento de Producción Animal, Facultad de Veterinaria, Universidad de León, 24071-León, Spain.
J Dairy Sci. 2006 Feb;89(2):549-52. doi: 10.3168/jds.S0022-0302(06)72117-8.
A total of 9,353 records for bulk tank total bacterial count (TBC) were obtained over 1 yr from 315 dairy ewe flocks belonging to the Sheep Improvement Consortium (CPO) in Castilla-León (Spain). Analysis of variance showed significant effects of flock, breed, month within flock, dry therapy, milking type and installation, and logSCC on logTBC. Flock and month within flock were important variation factors as they accounted for 22.0 and 22.1% of the variance, respectively. Considerable repeatability values were obtained for both random factors. Hand milking and bucket-milking machines elicited highest logTBC (5.31), whereas parlor systems with looped milkline (5.01) elicited the lowest logTBC. The implementation of dry therapy practice (5.12) showed significantly lower logTBC than when not used (5.25). Variability in logTBC among breeds ranged from 5.24 (Awassi) to 5.07 (Churra). However, clinical outbreaks of contagious agalactia did not increase TBC significantly. A statistically significant relationship was found between logTBC and logSCC, the correlation coefficient between the variables being r = 0.23. Programs for improving milk hygiene should be implemented for both total bacterial count and somatic cell count variables at the same time.
在一年时间里，从西班牙卡斯蒂利亚-莱昂地区绵羊改良协会（CPO）所属的315个奶羊养殖场获取了9353条关于散装罐总细菌数（TBC）的记录。方差分析表明，养殖场、品种、养殖场内月份、干奶期处理、挤奶类型及设施以及对数体细胞数（logSCC）对对数总细菌数（logTBC）有显著影响。养殖场和养殖场内月份是重要的变异因素，分别占方差的22.0%和22.1%。两个随机因素都获得了相当高的重复性值。手工挤奶和桶式挤奶机的对数总细菌数最高（5.31），而带有环形奶管的 parlour 系统（5.01）的对数总细菌数最低。实施干奶期处理（5.12）时的对数总细菌数显著低于未实施时（5.25）。不同品种间对数总细菌数的变异范围为5.24（阿瓦西羊）至5.07（丘拉羊）。然而，传染性无乳症的临床暴发并未使总细菌数显著增加。发现对数总细菌数与对数体细胞数之间存在统计学上的显著关系，变量间的相关系数r = 0.23。应同时针对总细菌数和体细胞数变量实施改善牛奶卫生的方案。
