Isolation And Identification Of Pathogenic Bacteria Of Cow Endomertritis And Clinical Therapy

Endometritis is a major disease in the cattle obstetric aspect,and seriously hindering the development of cattle industry.It is mainly caused by pathogenic microorganism infection after birth with initially mucous or purulent local inflammation at endometrium,while without timely treatment,the inflammation would diffuse,causing oophoritis,salpingitis and peritonitis.And ultimately the following chronic inflammation would affect the health and reproductive performance of cattle,causing serious economic losses.To provide reference basis for treatment of endometritis in a cattle farm in Henan Province,isolation and identification of bacteria in the uterine contents of diseased and without clinical symptoms cattle,bacterial susceptibility test,bacterial pathogenicity test,clinical therapy and routine blood test were applied in this study.1.Isolation and identification of bacteria in the uterine contents: The result of cultivation,isolation and purification of uterine contents of 48 cows suffering from endometritis showed that there were 13 bacterial species(78 isolates)in total,42 gram-positive and 36gram-negative isolates.Automated microbiology system for identification and antimicrobial susceptibility testing revealed the main pathogen is Escherichia coli,Staphylococcus aureus,Moraxella osloensis,Bacillus thuringiensis,hemolytic Staphylococcus,Streptococcus uberis and Bacillus cereus.The result of cultivation,isolation and purification of uterine contents of 30 without clinical symptoms cows showed that there were 11 bacterial species(32isolates)in total,17 gram-positive and 15 gram-negative isolates,while 9 samples bore no bacteria.In addition,automated microbiology system for identification and antimicrobial susceptibility testing revealed the main bacteria is Escherichia coli,Moraxella osloensis,Staphylococcus aureus,Bacillus cereus and Streptococcus uberis.What is more,the 11 species isolated from without clinical symptoms cows were consistent with that from diseased cows.2.Bacterial susceptibility test: The results of automated microbiology system for identification and antimicrobial susceptibility testing showed that the isolated 13 bacterial species were all sensitive to amoxicillin,ampicillin,ceftiofur and compound sulfamethoxazole.The rational therapeutic schedule can be made by combining with the results of susceptibility test and the actual production status.3.Bacterial pathogenicity test: All of the 13 bacterial species were used in this test.70 mice were randomly divided into 14 groups.The experimental groups were intraperitoneally inoculated with 0.5m L bacterial suspension respectively,while the control group was injected with 0.5m L saline,observing and recording the morbidity and mortality.The results showed that: the Kunming mice in the groups inoculated with Escherichia coli,Staphylococcus aureus,Bacillus cereus,Bacillus thuringiensis and hemolytic Staphylococcus were all died in 2d after inoculation.Especially in the group inoculated with Escherichia coli,the Kunming mice were all died in 2-3h after inoculation.In addition,the infected strains can be recovered from the diseased organs.4.Routine blood test: The blood samples from 48 cows suffering from endometritis and 30 without clinical symptoms cows were detected in this study.Comparing to the relevant blood indexes detection of healthy cows,the blood indexes detection of diseased cows showed that the number of white blood cells increased significantly(P<0.01),the percentage and number of neutrophils were also significantly increasing(P<0.01),while the number of lymphocytes was not significantly increasing(P>0.05),and the percentage of lymphocytes significantly reduced(P<0.01).These results suggested that the disease might be caused by bacterial infection,which was consistent with the results of identification of pathogenic microorganisms above.5.Clinical therapy of cows suffering from endometritis: Randomly selected 4 diseased cows as a control group in the 44 diseased cows,while the control group was treated with saline;the 40 diseased cows were randomly divided into four groups,the experimental groups were treated with amoxicillin,ampicillin sodium,ceftiofur and compound sulfamethoxazole respectively,the cure rate of experimental groups were 80.0%,70.0%,90.0% and 60.0%.Therefore,the clinical therapy with amoxicillin,ampicillin and ceftiofur had significant effects,and the use of ceftiofur generated optimal therapeutic effects.