Neospora caninum detection in a goat fetus

CAMPERO, L. M.; GOS, M. L.; MOORE, D. P.; REJIDOR-CERRILLO, J.; UNZAGA, J.M.; MORÉ, G.; ORTEGA-MORA, L. M.; VENTURINI, M.C.

Conferencia; 26th International Conference of the World Association for the Advancement of Veterinary Parasitology (WAAVP 2017); 2017

WAAVP

Neospora caninum is an apicomplexan protozoan responsible for abortion in ruminants, however caprine neosporosis needs further investigation. An Anglo Nubian fetus of approximately 2-month gestation was studied by Indirect fluorescence antibody test (IFAT), Immunoblot (IB), histopathology (HP), immunohistochemistry (IHC) and molecular assays (PCR; microsatellite genotyping). Interferon gamma knock-out mice were inoculated with a pool of organs and bled 21 days after for serological screening. The mother had IFAT titers of 1:3200 and 1:400 for N. caninum and T. gondii respectively, and the fetus was negative to both parasites by IFAT and IB. The fetus had severe autolysis and a generalized subcutaneous hemorrhage, severe multifocal necrotizing myocarditis and hepatitis, moderate interstitial pneumonia, and nephritis. N. caninum tachyzoites in clusters within myocardiocytes, always associated to HP lesions, were stained by IHC. Neospora caninum-DNA was detected in heart, lungs, liver, kidney and muscle from the fetus, and was negative for T. gondii by PCR. Mice were seronegative to N. caninum and T. gondii by IFAT. Microsatellite genotyping revealed a unique genetic profile that differed from previously reported N. caninum genotypes in other animal species. Our results indicate that N. caninum was efficiently transmitted to the fetus. The immature immunological system, as shown by the negative serological results, could explain the severity of lesions and the outcome of the disease. We report the first case of direct detection of N. caninum in a goat fetus in Argentina and N. caninum microsatellite genotyping in naturally infected goat worldwide.