Cow endometritis is common obstetrics in puerperal disease for bacterial infection, which causes large economic losses. The study included 12 cows with normal puerperium and 42 cows with endometritis on different farms in Heilongjiang province.All of bacteria in uterus secretions were cultured in anaerobic and aerobic conditions.8 bacteria were isolated in normal cows and 14 bacteria were isolated in cows with endometritis.The dominant pathogen in cows with endometritis were Escerichia coli, Staph...