MOLECULAR DETECTION OF Mycoplasma bovis IN SAMPLES OF BOVINE MASTITIS MILK WITH NEGATIVE GROWTH IN MICROBIOLOGICAL ISOLATION.
Mastitis, Mycoplasmosis, Polymerase Chain Reaction, Dairy Cattle.
Mastitis is an onerous disease, highly prevalent in dairy farms, which generates high costs for production, leading to significant economic losses. To control the occurrence of mastitis in dairy farms, a knowledge of its etiology is necessary. Among the bacteria responsible for outbreaks, Mycoplasma bovis stands out, which requires specific diagnostic techniques for its detection. In Santa Catarina, data on the presence of this microorganism in milk are not available. Therefore, the aim of the present study is to detect, through a PCR assay, the presence of M. bovis in samples of bovine mastitis milk negative to conventional microbiological isolation and collected in the Concórdia-SC microrregion. To date, 190 samples of mastitis milk have been collected that showed no growth in conventional bacteriological isolation. These samples were submitted to DNA extraction protocols using the phenol-chloroform or silica-guanidine method. The method using phenol-chloroform was more suitable than that of silica-guanidine, since the DNA recovery rate and degree of purity obtained were higher. The next step of the project is the detection of M. bovis using a previously described PCR. Thus, it is intended to elucidate cases of clinical and sub clinical mastitis, which were negative to conventional bacteriological growth, verifying the presence of M. bovis in the West region of Catarinense.