SURVIVABILITY OF MYCOPLASMA AGALACTIAE STRAINS IN CAPRINE MILK

The survivability of five strains of Mycoplasma agalactiae (2290, X-te ramo, 4941, 6/5277 and 549) causing caprine mastitis from different ge ographical locations, in artificially infected goat milk were investig ated. The assay was carried out using colour changing units (ccu/0.05 mi) in microplates as indicators of residual M. agalactiae at thermost atically controlled temperatures of 4, 18.2, 37 and 41 degrees C excep t for the room temperature from 0 to 5 days. All the strains tested we re more viable at 4 OC throughout the incubation period but showed dec line in number(s) by more than 4 logs at days 4-5. Similar patterns of decline were also noticed at temperatures of 37-41 degrees C, at whic h time no organism survived, beyond day 3. Three strains 2290, X-teram o and 6/52.27 survived at temperatures of 37 and 41 degrees C, respect ively. The gradual fall in the mean pH value of the infected milk from 6.90 +/- 0.04 at day 0 of infection to 4.10 +/- 0.69 at 41 degrees C did not appear to adversely affect the survival of the strains. It is concluded that there is a likely chance of recovery of some strains of M. agalactiae in milk at a temperature of 41 degrees C within 3 days.