Gonzalo C, Carriedo J A, Blanco M A, Beneitez E, Juárez M T, De La Fuente L F, Primitivo F San
Departamento de Producción Animal, Facultad de Veterinaria, Universidad de León, 24071-León, Spain.
J Dairy Sci. 2005 Mar;88(3):969-74. doi: 10.3168/jds.S0022-0302(05)72764-8.
Between January and December 2002, a total of 21,685 records for bulk tank milk somatic cell count (BTSCC) were obtained from 309 dairy ewe herds belonging to the Sheep Improvement Consortium in Castilla-Leon, Spain. Based on the first statistical model, ANOVA detected significant effects of herd, breed, month within herd, dry therapy, type of milking, contagious agalactia, and installations within machine milking on logBTSCC. A second statistical model was used on herds with machine milking to study the effect of the vacuum level and pulsation rate on BTSCC. Herd and month within herd were important variation factors as they explained 48.4 and 16.1% of the variance in BTSCC. Variability in logBTSCC among breeds ranged from 5.84 (Castellana) to 6.09 (Awassi and Spanish Assaf). Implementing dry-ewe therapy (5.91) significantly reduced logBTSCC compared with when it was not implemented (6.10). Hand milking elicited greater logBTSCC (6.07) than machine milking (5.94). Machine milking of ewes in milking parlors (logBTSCC: 5.88 to 5.94) was associated with better udder health than was the use of bucket-milking machines (6.04). Reduced vacuum levels and elevated pulsation rate during machine milking optimized BTSCC. In all cases, clinical outbreaks of contagious agalactia increased BTSCC. As a result, dry therapy was proposed as the main tool to reduce BTSCC. Optimization of milking-machine standards and parlor systems also improved udder health in dairy sheep.
2002年1月至12月期间，从西班牙卡斯蒂利亚-莱昂地区绵羊改良协会的309个奶羊养殖场收集了总计21685条散装罐牛奶体细胞计数（BTSCC）记录。基于第一个统计模型，方差分析（ANOVA）检测到养殖场、品种、养殖场内月份、干奶期治疗、挤奶类型、传染性无乳症以及机械挤奶设备等因素对logBTSCC有显著影响。对采用机械挤奶的养殖场使用第二个统计模型，研究真空度和脉动率对BTSCC的影响。养殖场和养殖场内月份是重要的变异因素，因为它们分别解释了BTSCC变异的48.4%和16.1%。各品种间logBTSCC的变异范围为5.84（卡斯蒂利亚纳品种）至6.09（阿瓦西品种和西班牙阿萨夫品种）。实施干奶期母羊治疗（logBTSCC为5.91）与未实施时（6.10）相比，显著降低了logBTSCC。手工挤奶的logBTSCC（6.07）高于机械挤奶（5.94）。在挤奶厅对母羊进行机械挤奶（logBTSCC：5.88至5.94）与使用桶式挤奶机（6.04）相比，乳房健康状况更好。机械挤奶过程中降低真空度和提高脉动率可优化BTSCC。在所有情况下，传染性无乳症的临床暴发都会增加BTSCC。因此，建议将干奶期治疗作为降低BTSCC的主要手段。优化挤奶机标准和挤奶厅系统也改善了奶羊的乳房健康状况。
