Cellular immunity of rabbits incase of parasite association (Treponema cuniculi and Eimeria sp.)

Abstract

Despite a huge number of studies, the uniqueness of antiparasitic immunity is so great that there is still insufficient knowledge of the factors contributing to the manifestation of the characteristics of immunity in mixed parasitic diseases of rabbits. Therefore, the question of the influence of the association of pathogens Treponema cuniculi and Eimeria sp. on indicators of cellular immunity of rabbits is relevant. The study was conducted on 59 male rabbits age 3–5 months of the Californian breed, selected by analogy. Animal were separated into two groups: healthy animals (control group) and sick animals (research group). Intensity of invasion was determined by the method of the Mac-Master. It has been established that the level of damage of rabbits by spirochetosis and eimeriosis was, on average, 1155.17 ± 184.87 and 6668.97 ± 284.16 pathogens in 1 g of feces. The count of T- and B-lymphocytes was determined by the method of spontaneous rosette-formation with sheep erythrocytes. Parasitizing the association of pathogens Treponema cuniculi and Eimeria sp. was revealed a high number of leukocytes (1.22 times, P < 0.001), which increased mainly due to lymphocytes, which were 1.45 times higher (P < 0.001), as well as neutrophilic metamyelocytes – 1.48 times (P < 0.05), eosinophils – 1.68 times (P < 0.001) and basophils – 1.57 times (P < 0.001) compared with similar blood parameters of healthy animals. In the blood of sick rabbits, the absolute number of T-lymphocytes (1.56 times, P < 0.001) and B-lymphocytes (3.02 times, P < 0.001) was significantly higher in comparison with a low number of O-lymphocytes (3.46 times, P < 0.001) compared with the control. This indicates the redistribution of lymphocytes to cells that carry T and B lymphocyte receptors on the plasma membrane. The absolute number of T-lymphocytes became high due to T-helpers, which in these animals were higher both in absolute (1.87 times, P < 0.001) and percentage (by 9.18%, P < 0.001) compared to control. Moreover, the percentage of T-suppressors in the blood of rabbits of the experimental group was significantly lower on 5.46% (P < 0.05) compared with the same blood count of healthy animals. Such a redistribution of the T-cell population in the peripheral blood of this group of rabbits led to an increase in the immunoregulatory index by 1.64 times (P < 0.01) than in healthy ones. High IRI and the number of T-active lymphocytes (by 28.23%, P < 0.05) in the blood of rabbits with parasitism of the association of pathogens Treponema cuniculi and Eimeria sp. indicate increased immune system tension.