Fish L, Mazuz M, Molad T, Savitsky I, Shkap V
Division of Parasitology, Kimron Veterinary Institute, PO Box 12, Bet Dagan 50250, Israel.
Vet Parasitol. 2007 Nov 10;149(3-4):167-71. doi: 10.1016/j.vetpar.2007.08.009. Epub 2007 Sep 11.
First Israeli Neospora caninum isolates were obtained from brain tissues of aborted fetuses (NcIs491 and NcIs580) from dairy farms endemic for neosporosis and maintaining cattle on zero grazing. Tissues from different parts of the fetus brains were used to infect Vero cells. Tachyzoites of N. caninum were first observed in cultures from days 30 and 32 after infection. To confirm the identity of the isolated parasites, DNA extracts from brains and cultures were tested by PCR with specific primers based on the Nc5 gene. Specific fragments were amplified by PCR from infected cultures of both fetuses on day 25. Susceptible seronegative gerbils (Meriones tristrami) were inoculated intraperitoneally with 10(3) to 10(5) tenfold dilutions of subculture tachyzoites. The inoculated gerbils developed specific antibodies to N. caninum, with end-point serum dilution of 1:4096 in the IFA assay, whereas no neurological signs or deaths were seen during 4 months of observation.
首批以色列犬新孢子虫分离株是从新孢子虫病流行的奶牛场中流产胎儿的脑组织（NcIs491和NcIs580）获得的，这些奶牛场采用零放牧方式饲养牛群。取自胎儿脑不同部位的组织用于感染Vero细胞。感染后第30天和第32天，在培养物中首次观察到犬新孢子虫速殖子。为了确认分离出的寄生虫的身份，基于Nc5基因，用特异性引物通过PCR对脑和培养物的DNA提取物进行检测。在第25天，从两个胎儿的感染培养物中通过PCR扩增出特异性片段。将易感的血清阴性沙鼠（长爪沙鼠）腹腔接种10³至10⁵倍稀释的传代培养速殖子。接种的沙鼠产生了针对犬新孢子虫的特异性抗体，在IFA试验中终点血清稀释度为1:4096，而在4个月的观察期内未观察到神经症状或死亡。
