山东省某奶牛场奶牛乳房炎的调查与分析

随机对某奶牛场的300头奶牛进行乳房炎调查和病原菌的分离鉴定,经SMT试验结果显示,该场奶牛乳房炎感染率49.67%,隐性乳房炎的阳性率占为32.33%,按左前、右前、左后、右后乳区的发病率差异均不显著（P〉0.05）;不同月份发病率差异极显著（P〈0.001）,夏季、冬季发病率高,卡方检验显示1～4胎发病率差异不显著（P=0.3126〉0.05）,但第4胎起发病率升高应引起注意。

Investigation and Analysis of Bovine Mastitis in A Certain Dairy Farm of Shandong Province

This study Investigated the prevalence of mastitis of 300 dairy cows chosen randomly from a certain farm and isolate and identify the pathogen.As it was demonstrated from the result of the SMT test,the infection rate of mastitis was 49.67% and the positive rate of subclinical mastitis was 32.33%.There is no significant difference（P0.05） of the incidence rate among the four mammary regions which were distinguished as left anterior,right anterior,left posterior and right posterior region.The diversity of the incidence rate of different months was quite significant（P0.001）.The incidence of mastitis turns out to be much higher when it was in summer and winter.Chi-square test showed that the difference of the incidence rate of the cow was not significant（P=0.31260.05） before its first four birth but from then on the incidence tends to be ascending.