Kravchenko N. Evaluation of dogs' resistance to infectious diseases on the basis of determination of NK system condition.

The investigation carried out in the above- mentioned direction has revealed that among utility dogs, sniffer dogs and close to them by habitus stray dogs there are dogs having highly-, median-, and weakly organized systems of NK-resistance. The former group of dogs is the group of dogs with NK resistance index similar to that in wolves. According to the data received the above dogs had NKs in blood - 14,7±0,21 %, their activity was 92,0±0,3 %. As a rule, the above dogs had tissue NKs in all the places where they had to be. These unvaccinated against parvovirosis, adenovirosis CAV-2, canine distemper, leptospirosis dogs do not have the above diseases. The second group of dogs was the group of dogs having NKs in blood - 10,1±0,3 %, their oncocidity was 73,4±0,17 %. The dogs of the second group had no tissue NKs in the lymphoid formations of the small intestine wall. They have the virosis and bacteriosis under investigation. It is supposed that pulmonary and enteral forms of canine distemper in dogs having such system of NK resistance are connected with the lack of tissue NKs in the respiratory system or in the intestine. According to the data received during the investigation the dogs having weakly organized system of NK resistance had 7,2 % NKs in blood and their oncocidity was 42,0±0,15 %, the dogs did not have any tissue NKs in most places where they had to be, namely: palatine tonsils, liver, surface and internal lymphatic nodes but more often in walls of intrapulmonary bronchioles and small intestine, in lymphatic nodes of ileocecal valve. NK-resistance system has three stages of its development from the birth to 3 months, it improves, from 3 to 6 months it does not change and at the end of the 6th month it quickly gets its definite character. Under the influence of treatment its indices improve or become worse, the improvement proves the properly chosen scheme of treatment. The vaccine prophylaxis affects NK resistance, on the 5-7th day after vaccination the resistance index reduces and for 2-3months this reduction continues and after that there is slow return to the initial state.