PHAGOCYTIC ACTIVITY OF LEUKOCYTES IN PIGS, PRODUCT OF NARROW INBREEDING

The study aimed to determine the effect of inbreeding on phagocytic activity in pigs from the Danube White breed. Thirty-three pigs, each weighing 80 kg, divided into 4 groups were studied: female and male outbred and female and male inbred pigs with inbreeding coefficient Fx=0.25. The phagocytosis was performed via mixing equal volumes of 0.1 mL heparinized blood and 0.1 mL suspension of 24-hour microbial culture of Staphylococcus aureus (strain 209) with a density of 2×10 9 cfu /mL. After a 30-min incubation in a thermostat at 37 o C and vigorous ahaking at 5 min intervals, blood smears were prepared on clean defatted glass slide and stained according to GiemsaRomanovsky. In each blood smear, 100 leukocytes were counted under oil immersion on a light microscope. Two parameters of phagocytic activity were determined: the phagocytosis percentage (the ratio of leukocytes that phagocytized bacteria and the total leukocyte counts) and phagocytic number (the average number of bacteria , phagocytized by one leukocyte). A trend towards a higher phagocytic activity in female pigs vs males was present. The phagocytic numbers and the % phagocytosis tended to decrease in the animals, product of inbreeding, compared to outbred animals at the same age, but not significantly. The coefficients of phenotypic correlations between the phagocytosis percentage and the phagocytic number were determined. They were all high, positive and significant. The correlation coefficients in inbred animals were considerably higher.