Investigation On Occult Mastitis Of Dairy Cows In Lingshou County And Evaluation Of Treatment Effect

Subclinical mastitis in cows is a common disease that hinders the development of the dairy industry in Lingshou County.The use of Western medicine for treatment yields quick results but has led to increasing concerns over bacterial resistance and drug residues.Traditional Chinese medicine treatment,while residue-free,is slow in effectiveness and thus has not been widely adopted.Combining these two treatment methods adaptively to treat subclinical mastitis in cows can provide groundbreaking guidance for the scientific prevention and control of dairy farms in Lingshou County.Therefore,this study focuses on selected large-scale dairy farms in Lingshou County to investigate the incidence of subclinical mastitis,isolate and identify pathogens,conduct drug sensitivity tests,and formulate prevention and control measures.Throughout 2019,a survey on the incidence of subclinical mastitis was conducted in four different scale dairy farms in Lingshou County using the LMT method,and the collected data were analyzed and summarized.Subsequently,50 cows with subclinical mastitis were selected,and 125 milk samples were collected for bacterial isolation,cultivation,and biochemical identification.Drug sensitivity tests were performed on the isolated pathogens.Finally,10 healthy cows were selected as the blank group,and 80 cows with subclinical mastitis were randomly divided into control group,traditional Chinese medicine treatment group,Western medicine treatment group,and combined Chinese-Western medicine treatment group,with 20 cows in each group.Feeding experiments were conducted on days 0,4,and 8 after treatment,and data were recorded.The LMT method and SCC method were used to assess treatment effectiveness.The results are as follows:(1)In 2019,a total of 46,430 cows were tested in four dairy farms in Lingshou County.Among them,16,351 cases of subclinical mastitis were detected,with an average incidence rate of 35.21%.The occurrence of subclinical mastitis in cows was found to be related to the month and season,with the highest incidence in summer.The incidence of subclinical mastitis in cows was positively correlated with parity and age,with a significant increase in cows with more than four parities.The incidence rate of subclinical mastitis in cows with seven or more parities reached75%.The incidence also increased significantly in cows over five years old,with the highest incidence rate occurring in cows over eight years old,reaching 66.67%.Additionally,there was a positive correlation between the lactation period of cows and the incidence of subclinical mastitis.The highest incidence rate was observed in cows with a lactation period of more than 300 days.Cows with a daily milk production of ≤ 20 kg had a higher incidence of subclinical mastitis compared to those with a daily milk production of ≥ 20 kg.(2)According to this experiment,it was found that the main pathogens causing subclinical mastitis in cows in Lingshou County are Staphylococcus aureus and Escherichia coli.The results of drug sensitivity tests showed that both Staphylococcus aureus and Escherichia coli were resistant to penicillin,streptomycin,erythromycin,rifampicin,and tetracycline,while they were sensitive to amoxicillin,enrofloxacin,and cefotaxime.(3)The experiment selected cows with similar degrees of subclinical mastitis,with an average somatic cell count of approximately 750,000 cells/m L in the milk,and the difference was not significant.In terms of effectiveness,the combined Chinese-Western medicine group showed the best therapeutic effect.In terms of somatic cell count,all treatment groups showed a decrease in the somatic cell content in the milk after treatment,except for the control group.In comparing the milk quality,it was not possible to determine the superiority or inferiority of milk quality based on factors such as milk protein and lactose,which may be influenced by inflammation.However,by measuring the relatively stable factor of milk fat content,it was found that the combined Chinese-Western medicine treatment group effectively improved the milk fat content of diseased cows,demonstrating good efficacy.The results of this study indicate that the incidence of subclinical mastitis in cows in Lingshou County is correlated with the month,season,parity,age,lactation period,and daily milk production of the cows.The main pathogens in this region are Staphylococcus aureus and Escherichia coli.Through comparing the effectiveness of different treatment methods and analyzing the composition of milk samples,it was found that the combined Chinese-Western medicine treatment for subclinical mastitis in cows had a higher effectiveness rate compared to single Chinese medicine or Western medicine treatment.Additionally,the combined treatment had a shorter treatment duration and resulted in higher milk quality.