| reliability of environmental sampling to quantify mycobacterium avium subspecies paratuberculosis on california free-stall dairies. | the reliability of environmental sampling to quantify mycobacterium avium ssp. paratuberculosis (map) based on collector and time was evaluated. fecal slurry samples were collected using a standardized protocol simultaneously by 2 collectors of different experience levels. samples were collected from 30 cow pens on 4 dairies every other day on 3 occasions while cow movements between pens were minimal. the 4 study herds had moderate map seroprevalence and were housed in free-stall dairies in cent ... | 2009 | 19620644 |