SEARCH OF THE POSSIBLE FACTORS OF TRANSMISSION OF THE LEUKOSIS VIRUS OF CATTLE BY ENDOBIOTIC WAYS

The gastrointestinal tract (GIT) of vertebrates is colonized by an extremely diverse anaerobic microbial community consisting of archaea, bacteria, fungi, and various protozoa. Trichostomic ciliates are among the most characteristic and largest protists of this complex enzymatic association, inhabiting both the anterior and posterior parts of the gastrointestinal tract. The transfer of ciliates – endobionts, occurs more often when animals come into contact with other animals of the herd. Regurgitation in cattle occurs reflexively, regularly and frequently, while a significant number of ciliates penetrate the oral cavity. In most ruminants, such social behavior as grooming involves licking the muzzle and sometimes the oral cavity of relatives, with some ciliates being transferred from the mouth of one animal to the mouth of another and soon swallowed. According to the results of PCR-studies of endobiotic ciliates from the rumen of cows for the presence of bovine leukemia virus (BLV) in them, a negative result was obtained in all samples. Thus, in a homogenized material consisting of different types of ciliates from 12 cows that were spontaneously infected, a PCR methods was obtained negative for the presence of the genetic material of bovine leukemia virus. In our opinion, the data obtained do not completely disprove the hypothesis of endobiotic transmission of BLV due to the relatively small sample of carrier animals and insufficient improvement of the PCR diagnostic method, and these studies should be continued using a larger number of infected with BLV animals and different diagnostic methods.