Sandhu K S, Ball M S, Kumar H, Sharma S, Sidhu P K, Sreekumar C, Dubey J P
Department of Epidemiology and Preventive Veterinary Medicine, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana 141004, India.
J Parasitol. 2007 Dec;93(6):1374-7. doi: 10.1645/GE-1317.1.
Neospora caninum is now recognized as a major cause of abortion in cattle worldwide, but there is no report of N. caninum infection in cattle in India. Serum samples from 427 dairy cattle and 32 dairy water buffaloes from 7 organized dairy farms located in Punjab, India, were tested for N. caninum antibodies using a commercial monoclonal antibody-based competitive enzyme-linked immunosorbent assay (ELISA). Antibodies to N. caninum were found in 35 of 427 cattle from 6 of the 7 farms; 9.6% of cows, 5.1% of heifers, and 5.0% of calves were seropositive, suggesting postnatal transmission of N. caninum on the farm. Antibodies to N. caninum were found in 16 of 32 buffaloes tested from 2 dairy farms. In total, 64 cattle and 16 buffalo sera already tested by ELISA were also evaluated by an indirect fluorescent antibody test (IFAT) to verify ELISA results. Of the 64 cattle samples, 29 sera were negative by both tests and of the 35 ELISA-positive sera, 12 had IFAT titers of 1:100 or higher (1 had IFAT titer of 100, 2 had IFAT titer of 200, and 9 had IFAT titers of 400 or higher). Of the 16 buffalo sera positive by ELISA, 1 had an IFAT titer of 1:400. Thus, antibodies to N. caninum were demonstrated in cattle sera by 2 serologic methods. To our knowledge this is the first report of N. caninum infection in cattle and buffaloes in India.
犬新孢子虫现已被公认为是全球范围内牛流产的主要病因，但印度尚无牛感染犬新孢子虫的报道。采集了印度旁遮普邦7个规模化奶牛场的427头奶牛和32头奶水牛的血清样本，采用基于商业单克隆抗体的竞争酶联免疫吸附测定（ELISA）检测犬新孢子虫抗体。在7个农场中的6个农场的427头牛中，有35头检测到犬新孢子虫抗体；9.6%的母牛、5.1%的小母牛和5.0%的犊牛血清呈阳性，提示犬新孢子虫在农场存在产后传播。在2个奶牛场检测的32头水牛中，有16头检测到犬新孢子虫抗体。总共对64份已通过ELISA检测的牛血清和16份水牛血清也采用间接荧光抗体试验（IFAT）进行评估，以验证ELISA结果。在64份牛样本中，29份血清两种检测均为阴性，在35份ELISA阳性血清中，12份IFAT效价为1:100或更高（1份IFAT效价为100，2份IFAT效价为200，9份IFAT效价为400或更高）。在16份ELISA阳性的水牛血清中，1份IFAT效价为1:400。因此，通过两种血清学方法在牛血清中均检测到犬新孢子虫抗体。据我们所知，这是印度牛和水牛感染犬新孢子虫的首次报道。
