School of Veterinary Medicine, Faculty of Agriculture and Natural Resources, University of Namibia, Windhoek, P. Bag 13301, Namibia.
Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa.
Trop Anim Health Prod. 2020 Nov;52(6):3099-3107. doi: 10.1007/s11250-020-02332-4. Epub 2020 Jun 23.
Cattle production is the major livestock production activity and the mainstay of Namibia's economy. Sustained beef exports are contingent on a sound sanitary environment where diseases such as brucellosis are under control. In this retrospective study, 49,718 bovine brucellosis testing results from 2004 to 2018 were analyzed to determine the proportion of sero-positive cattle and herds, and the spatial distribution of positive reactors from commercial and communal areas. In total, 244 positive reactors were identified based on the Rose Bengal Test (RBT) and the Complement Fixation Test (CFT) in series, giving an overall proportion of infected animals of 0.49% (244/49,718; 95% CI, 0.43-0.56%) and an overall proportion of infected herds of 9.26% (78/842; 95% CI, 7.49-11.41%). There was a higher proportion of sero-positive communal herds (33.09%) and cattle (10.27%) than commercial herds (4.67%) and cattle (0.24%; p < 0.05). Annually, the proportion of positive reactors was 0-1.37% in the commercial area and 0-52.38% in the communal areas, with a clear decline in positive reactors in the communal areas. Within the commercial sector, the proportion of positive reactor dairy, beef, and export cattle was 0.19% (51/27,067; 95% CI, 0.14-0.25%), 0.30% (48/16,098; 95% CI, 0.22-0.40%), and 0.33% (16/4811; 95% CI, 0.20-0.54%), respectively. Abortions were found to be the major reason for Brucella testing in the communal areas. About 12.65% (96/759) of abortion-linked sera tested positive in the communal areas, but none were positive in beef or dairy cattle. Widespread vaccination of cattle and robust planned surveillance is recommended to reduce the incidence of the disease, its associated production losses and public health risk.
牛只生产是纳米比亚主要的畜牧生产活动，也是纳米比亚经济的支柱。持续的牛肉出口取决于健全的卫生环境，其中包括控制布鲁氏菌病等疾病。在这项回顾性研究中，对 2004 年至 2018 年的 49718 份牛布鲁氏菌病检测结果进行了分析，以确定商业和社区地区血清阳性牛和牛群的比例，以及阳性反应牛的空间分布。基于虎红平板凝集试验（RBPT）和补体结合试验（CFT）的串联检测，共发现 244 头阳性反应牛，感染动物的总体比例为 0.49%（244/49718；95%CI，0.43-0.56%），感染牛群的总体比例为 9.26%（78/842；95%CI，7.49-11.41%）。社区牛群（33.09%）和牛（10.27%）的血清阳性比例高于商业牛群（4.67%）和牛（0.24%；p<0.05）。每年，商业区域的阳性反应牛比例为 0-1.37%，社区区域的阳性反应牛比例为 0-52.38%，社区区域的阳性反应牛数量明显减少。在商业部门，阳性反应奶牛、肉牛和出口牛的比例分别为 0.19%（51/27067；95%CI，0.14-0.25%）、0.30%（48/16098；95%CI，0.22-0.40%）和 0.33%（16/4811；95%CI，0.20-0.54%）。流产被认为是社区区域布鲁氏菌检测的主要原因。在社区区域，约 12.65%（96/759）与流产相关的血清检测呈阳性，但在肉牛和奶牛中均未呈阳性。建议广泛接种牛只疫苗并进行强有力的计划监测，以降低疾病发病率、相关生产损失和公共卫生风险。
