Johne's Disease: Mycobacterium paratuberculosis Super-shedders
Detection and Contribution to Passive Shedding (False-positive Fecal Cultures)
DOI:
https://doi.org/10.21423/aabppro20064769Keywords:
John's disease, super-shedder, MAP, passive shedding, dairy cattleAbstract
This report further documents the critical importance of identifying super-shedders, since they contribute billions of MAP CFU daily to the environment, serving to disseminate MAP to susceptible cattle. In many herds, this results in significant numbers of culture-positive fecal samples through passive shedding. The frequency of super-shedders among culture-positive cattle in infected herds is unknown. However, our preliminary investigations have shown that each of three current herds has at least one super-shedder cow, with five super-shedder cows having been identified among the 7.1% ( 41 of 575) of culture-positive cattle in the herds. Our preliminary estimates are that 10% of heavy shedders (or about 2 to 3% of all culture-positive cattle at a single time-point) may be super-shedders, excreting >10 billion CFU MAP per cow per day.