约旦北部阿瓦西绵羊临床和亚临床乳腺炎的流行病学研究。

Epidemiological studies of clinical and subclinical ovine mastitis in Awassi sheep in northern Jordan.

作者信息

Lafi S Q, al-Majali A M, Rousan M D, Alawneh J M

机构信息

Department of Veterinary Clinical Sciences, Faculty of Veterinary Medicine, Jordan University of Science and Technology, Irbid, Jordan.

出版信息

Prev Vet Med. 1998 Jan;33(1-4):171-81. doi: 10.1016/s0167-5877(97)00048-2.

DOI:10.1016/s0167-5877(97)00048-2

PMID:9500172

Abstract

Forty-six Awassi sheep flocks selected by stratified random sampling were subjected to a cross-sectional study to determine the prevalence of intramammary infections, to assess the influence of flock size and parity on the prevalence of somatic cell count (SCC) and to identify major udder pathogens. Of the 3472 udder halves examined, 29.8% had over 10(6) SCC/ml and 0.03% had dry teats due to chronic mastitis. Flocks with 30-49 milking ewes (small flock size) were much younger (P < 0.001) than flocks with 50-99 ewes (medium) and flocks with > or = 100 ewes (large). Pairwise analysis of the InSCC of both halves of the udders revealed significant mean differences for small and large flock size (P < 0.05), and for medium and large flock size (P < 0.001). Mean InSCC was lower (P < 0.05) in samples obtained from the left half compared with samples of the right half of the udder. Multiparous ewes had higher (P < 0.001) mean InSCC than primiparous ewes. Also, ewes with twin lambs had higher (P < 0.001) mean InSCC in the right half of the udder compared with single-lamb ewes. Samples collected in January (winter) had lower (P < 0.05) mean InSCC compared with samples collected in June. The most common organisms isolated from subclinical mastitis cases were coagulase-negative Staphylococci (17.8%), E. coli (13.6%), Streptococcus agalactiae (6.8%) and Staphylococcus aureus (6.8%). Of the 46 flocks, 20 were monitored monthly for 9 consecutive months to determine the incidence of clinical mastitis diagnosed by shepherds or/and sheep farmers with major pathogens. The incidence of clinical mastitis (expressed as the number of clinical cases per 100 ewe-months) were 2.1 +/- 1.9 (SD), 1.9 +/- 1.1, and 1.2 +/- 2.1 for small, medium and large flocks size strata, respectively. The overall population estimate was 1.7 +/- 0.02 cases per 100 ewe-months. The most-common clinical isolates were S. aureus (22% of all clinical isolates) and E. coli (14.2%).

摘要

通过分层随机抽样选取了46个阿瓦西羊群进行横断面研究，以确定乳房内感染的患病率，评估羊群规模和胎次对体细胞计数（SCC）患病率的影响，并识别主要的乳房病原体。在检查的3472个乳房半侧中，29.8%的乳房半侧SCC超过10⁶/ml，0.03%的乳房半侧因慢性乳腺炎出现干奶。拥有30 - 49只产奶母羊的羊群（小群体规模）比拥有50 - 99只母羊的羊群（中等群体规模）和拥有≥100只母羊的羊群（大群体规模）年轻得多（P < 0.001）。对乳房两侧的InSCC进行两两分析发现，小群体规模和大群体规模之间（P < 0.05）以及中等群体规模和大群体规模之间（P < 0.001）存在显著的平均差异。与从乳房右侧采集的样本相比，从乳房左侧采集的样本平均InSCC较低（P < 0.05）。经产母羊的平均InSCC高于初产母羊（P < 0.001）。此外，与单羔母羊相比，产双羔的母羊乳房右侧的平均InSCC更高（P < 0.001）。1月份（冬季）采集的样本平均InSCC低于6月份采集的样本（P < 0.05）。从亚临床乳腺炎病例中分离出的最常见微生物是凝固酶阴性葡萄球菌（17.8%）、大肠杆菌（13.6%）、无乳链球菌（6.8%）和金黄色葡萄球菌（6.8%）。在46个羊群中，连续9个月每月对20个羊群进行监测，以确定由牧羊人或/和养羊户诊断出的主要病原体引起的临床乳腺炎发病率。小、中、大群体规模层的临床乳腺炎发病率（以每100只母羊 - 月的临床病例数表示）分别为2.1±1.9（标准差）、1.9±1.1和1.2±2.1。总体人群估计发病率为每100只母羊 - 月1.7±0.02例。最常见的临床分离株是金黄色葡萄球菌（占所有临床分离株的22%）和大肠杆菌（14.2%）。