The use of PCR to detect Neospora caninum DNA in the blood of naturally infected cows.

Twelve 2-year old heifers in their fifth month of gestation when pregnancy tested were used in this study. Six heifers aborted at approximately 4 months of gestation and had blood samples drawn less than 6 weeks after the abortions were identified. Blood samples were also drawn from three sero-positive pregnant and three sero-negative pregnant heifers. DNA was isolated from the samples and a 350 bp fragment of the Nc-5 gene was PCR amplified using primer pair Np21+ and Np6+. Also, the Internal Transcribed Spacer 1 (ITS1) was PCR amplified using Tim 3 and Tim 11 primer pair. The Nc-5 gene fragment was cloned, sequenced and the sequence BLAST-tested. Similarly, the ITS1 product was sequenced and BLAST-tested. The BLAST test results revealed that Neospora caninum DNA was present in these blood samples indicating that polymerase chain reaction can be used in the detection of N. caninum DNA in the blood of sero-positive cows.