Mycobacterium avium subsp. paratuberculosis as an Emergent Pathogen in Raw Ovine Milk Produced in Central Italy

This study was performed to verify the safety of raw ovine milk and its role as a vehicle for Mycobacterium avium subsp. paratuberculosis (MAP) transmission. Milk samples from 697 randomly chosen adult sheep, reared in 17 dairy flocks in central Italy, were examined using Ziehl Neelsen (ZN) staining, bacteriological culture (BC), and indirect ELISA tests. Using ELISA, we identified 70 % of MAP-infected ovine dairy farms. MAP infection was confirmed in 24.3 and 21.6 % of ELISA-positive milk samples (n = 37) by ZN staining and BC, respectively. A fair (k = 0.43) and slight (k = 0.33) agreement was observed between ELISA–ZN and ELISA–BC, respectively. The presence of MAP in raw ovine milk produced in central Italy confirmed a risk of potential transmission to humans through consumption of milk and cheese manufactured from unpasteurized milk.