Re-emerging Equine Arteritis Virus (EAV) variants

n where p ¼ overall proportion of individual qPCR positive straws and n ¼ number of straws tested (Table 2). 95% Confidence Intervals were adjusted for the clustering of observations in the five ejaculates. The qPCR assay effectively identified T. equigenitalis DNA contaminating multiple straws of different ejaculates processed over four years. Extensive variation in Ct values within and between batches was possibly due to effects of semen collection and processing including addition of antibiotic-containing extender. In conclusion, this data suggested that > three straws per batch should be evaluated for 95% confidence of detecting T. equigenitalis in cryopreserved semen from a potential carrier stallion but the lower range of the 95% CI suggests a larger study is necessary to improve precision of this estimate. Infectivity of the bacterium after cryopreservation warrants further investigation.