Ott S L, Wells S J, Wagner B A
Center for Epidemiology, US Department of Agriculture, Fort Collins, CO 80521, USA.
Prev Vet Med. 1999 Jun 11;40(3-4):179-92. doi: 10.1016/s0167-5877(99)00037-9.
Johne's disease ('paratuberculosis') is a chronic, infectious, wasting disease that affects dairy cattle. Estimation of its impact on herd productivity and corresponding economic loss on US dairy operations was part of the USDA National Animal Health Monitoring System's (NAHMS) 1996 national dairy study. Johne's-positive herds experience an economic loss of almost US$ 100 per cow when compared to Johne's-negative herds due to reduced milk production and increased cow-replacement costs. For Johne's-positive herds that reported at least 10% of their cull cows as having clinical signs consistent with Johne's disease, economic losses were over US$ 200 per cow. These high-prevalence herds experienced reduced milk production of over 700 kg per cow, culled more cows but had lower cull-cow revenues, and had greater cow mortality than Johne's-negative herds. Averaged across all herds, Johne's disease costs the US dairy industry, in reduced productivity, US$ 22 to US$ 27 per cow or US$ 200 to US$ 250 million annually.
约内氏病（“副结核病”）是一种影响奶牛的慢性、传染性消耗性疾病。评估其对牛群生产力的影响以及美国奶牛场相应的经济损失，是美国农业部国家动物健康监测系统（NAHMS）1996年全国奶牛研究的一部分。与约内氏病阴性牛群相比，约内氏病阳性牛群每头奶牛的经济损失近100美元，原因是产奶量下降和奶牛更换成本增加。对于报告至少10%的淘汰奶牛有与约内氏病相符临床症状的约内氏病阳性牛群，每头奶牛的经济损失超过200美元。这些高患病率牛群的奶牛产奶量每头减少超过700千克，淘汰的奶牛更多，但淘汰奶牛的收入更低，且奶牛死亡率高于约内氏病阴性牛群。在所有牛群中平均计算，约内氏病使美国奶牛业因生产力下降，每头奶牛损失22至27美元，或每年损失2亿至2.5亿美元。
