Abstract
The main goal of this study is the application of polymerase chain reaction in dairy farm for diagnosis of the false negative Mycoplasma isolates from bovine mastitis. A total number of 350 and 90 milk samples were collected from udder quarters of 180 and 30 cows and buffaloes, respectively and examined by standard microbiological techniques as well as polymerase chain reaction (PCR). Mycoplasmas were isolated in percentages of 7.14%, 8% from subclinically mastitic cows and buffaloes, respectively and in percentages of 11.85%, 10% from clinically mastitic cows and buffaloes, respectively. Typing of Mycoplasma revealed 6 strains (24%) Mycoplasma bovis and 10 strains (40%) Mycoplasma bovigenitalium, 7 strains (28%) Mycoplasma arginini while the other two strains (8%) were Mycoplasma bovirihinis. Isolation of Mycoplasma from udder tissue in cows and buffaloes were in a percentage of 10% in cows while no Mycoplasma isolates were obtained from buffaloes' udder tissues. Application of PCR on these isolates and milk samples revealed 100% sensitivity and specificity. The PCR is simple, rapid, highly specific and accurate test for identification of Mycoplasma bovis and Mycoplasma bovigenitalium. In addition, the negative samples for Mycoplasmas can be detected even if the samples or the broth cultures were contaminated with bacteria.