Detection of Neospora caninum DNA in semen of experimental infected rams with no evidence of horizontal transmission in ewes

Study on the use of toltrazuril to eliminate Neospora caninum in congenitally infected lambs born from experimentally infected ewes

“…An S/P ratio of ≥11.8% was regarded as positive as described by Reichel et al (2008). Sera from all ewes were also tested one month post-inoculation with a western blot as described previously (Syed-Hussain et al, 2013) to confirm their infection status and all sera from 12 week old lambs were similarly tested.…”

Vertical transmission in experimentally infected sheep despite previous inoculation with Neospora caninum NcNZ1 isolate

“…These were prepared and administered as previously described (Syed-Hussain et al, 2013). These had been passaged approximately 20 times in cell culture since the original isolation.…”

“…All sera collected were tested as previously described (Syed-Hussain et al, 2013) using a commercial ELISA test kit (Chekit* N. caninum Antibody Test Kit, IDEXX Laboratories, Australia). An S/P ratio of ≥11.8% was regarded as positive as described by Reichel et al (2008) who reported a sensitivity of 100% and specificity of 98%.…”

“…All sera from ewes were tested one month post inoculation to confirm their infectivity status while all sera from lambs in Year 1 and 2 respectively were also analyzed using Western blot as described previously (Syed-Hussain et al, 2013). This assay uses reduced antigens and for this study, sera that recognized at least one IDA with molecular weight (MW) of 17, 25-29, 30-33 or 37 kDa were considered positive for N. caninum.…”

“…One experimental study found that using the local NcNZ isolates, sheep aborted in a dose dependent manner and at least 5000 tachyzoites were required to induce abortion when inoculated into ewes at Day 90 of gestation (Weston et al, 2009). An additional study has shown that transmission via semen is unlikely to occur, even when rams were inoculated with a large challenge (Syed-Hussain et al, 2013). Sheep, like cattle, can be infected by ingesting oocysts, however in the single report using the NC-2 isolate, the inoculation dose was high (10 4 oocysts) (O'Handley et al, 2002).…”