| bovine mastitis in ontario due to mycoplasma agalactiae subsp. bovis. | bovine mastitis caused by mycoplasma agalactiae subsp. bovis was first diagnosed in 16 of 55 cows in an ontario herd in feburary 1972. a total of 182 of 598 (30.4%) cows from 33 of 64 (51.5%) farms in widely separated areas of the province were culturally positive. herd incidence varied from 15 to 40% with one closed herd having an incidence of 61%. four herds were investigated culturally and serologically by the growth inhibition test for 15 months. in the acute phase the organism was present i ... | 1976 | 1000385 |