- Volume 19 Issue 2
In order to know the main causative agent and distribution of the agents in Gram-negative bacillus infections of bovine udders, one hundred and forty-eight cultures of Gram-negative bacilli isolated from clinical cases of mastitis during lactation over a period of 2 years in 6 herds of 180 Holstein cows were studied. Escherichia coli occupied 54.7% of the isolates was the most frequently isolated Gram-negative bacillus. 30 of the isolates (20.3%) were Enterobacter aerogenes, but Enterobacter cloacae was not isolated. Remaining isolates were Klebsiella pneumoniae, Proteus spp., Preudomonas aeruginosa and Alcaligenes faecalis. Most of the isolates (75.0%) were isolated from rear quarters.