Application Of PCR Diagnosis And Drug Sensitivity Detection In Prevention And Treatment Of Dairy Cow Mastitis

Mastitis not only harms the health of dairy cows,but also reduces the milk yield and the quality of dairy products.It is one of the most important causes of the economic losses of dairy farming in the world.Dairy cow mastitis is mainly divided into clinical mastitis and recessive mastitis.The clinical symptoms of clinical mastitis are obvious and easy to diagnose;however,recessive mastitis,in addition to the reduction of milk production in dairy cows,has no other obvious clinical symptoms.In actual production,it is hidden mastitis that causes greater harm.Therefore,timely and accurate diagnosis and finding effective prevention and treatment methods are extremely important for the prevention and control of cow mastitis.In order to explore and solve the above problems and improve the diagnosis and prevention efficiency of mastitis,the following research was conducted.Research content I.The infection of mastitis and the isolation and identification of pathogenic bacteriaResearch content 1:Infection of mastitis and isolation and identification of pathogenic bacteria.Using the PathoProof mastitis PCR diagnostic system,79 milk samples from a dairy farm in Taicang City were quickly isolated and identified as the main pathogens of cow mastitis.Pathogens were detected in 79 milk samples,and the detection rate was 100%.A total of 12 pathogens were detected,of which Staphylococcus infection rate was the highest,reaching 81.01%,followed by Streptococcus agalactiae,and the infection rate was 67.09%.Staphylococcus and Streptococcus agalactiae are the two main pathogens in the pasture.The infection was mainly cross-mixed,the cross-infection rate of the two kinds of bacteria was 27.85%,and the proportion of three or more kinds of bacteria infection was 63.29%.During the PCR assay,the ?-lactamase resistance gene was detected in most pathogens of the pasture.Research content 2;Detection of drug susceptibility of main pathogenic bacteria of mastitis.The OptiRead drug sensitivity detection system was used to carry out the susceptibility test of conventional antibacterial drugs to the main pathogens isolated.In the experiment,Staphylococcus was found to be sensitive to ceftiofur,ampicillin,erythromycin,etc.,among which ceftiofur was the best;Streptococcus agalactiae was sensitive to ampicillin,ceftiofur,penicillin,erythromycin,etc.Among them,ampicillin is the best;since most pathogens carry the?-lactamase resistance gene,it is recommended to use ?-lactam antibiotics carefully in combination with drug sensitivity results to avoid the emergence of drug-resistant strains.Research content 3.Application of PCR diagnosis and drug sensitivity detection in prevention and treatment of dairy cow mastitis.According to the results of the above two studies,the cows were treated,and the application of PCR and drug sensitivity detection technology in production practice was discussed by analyzing the cure rate,treatment cycle,incidence rate,and DHI index of large cylinder milk samples.During the experiment from March to June 2016,the average incidence of cow mastitis was 3.03%,which was 0.25%lower than 3.28%in the same period of 2015;the average quality cycle of 79 cows with mastitis was 5.14 days,cured.The rate was 96.20%,which was 0.97 days shorter than the average treatment period of 6.11 days in 2015.The average cure rate was 92.75%and the increase was 3.45%.The average recurrence rate of mastitis decreased by 1.7%.The somatic cell number of milk was four months after the experiment.There was also a significant decline during the period.Through the application of the above two detection technologies,not only the use of antibiotics is reduced,the treatment cycle is shortened,the cure rate is improved,the treatment cost is saved,the milk quality is improved,and the quality and safety of the milk products are guaranteed.In conclusion,it indicates that PathoProof mastitis PCR diagnosis technology and OptiRead drug sensitivity detection technology can provide guidance to dairy farms in actual production through systematic analysis of pathogenic bacteria detection and drug sensitivity of dairy cow mastitis.Provide guidance for clinical rational,targeted drug use and improve the prevention and treatment of dairy cow mastitis.