Evaluation of natural rabbit blood resistance in response to the probiotic drug “SUB-PRO”

The study examines the effects of probiotic microorganisms in the SUB-PRO preparation on indicators of natural resistance in rabbits. The experiment involved 45 French hybrid breed rabbits, divided into three groups of 15 animals each—two experimental groups and one control group. A lighting schedule was maintained, providing 16 h of light and 8 h of darkness. The diet for the control group consisted only of basic feed. In addition to the standard diet, rabbits in the experimental groups received the SUB-PRO supplement, which contains the Bacillus subtilis strain VKPM B-2335, at dosages of 0.1 and 0.2 kg per ton of compound feed in the second and third groups, respectively. The hematological analysis indicated that all key blood parameters in both groups of animals were in the normal range for their physiological state. At the end of the fattening period, hemoglobin levels in the experimental groups showed an increase. In the second group, this measure was significantly higher than in the control group by 3.00 g/l (2.70%) with P ≥ 0.95, while in the third group, it increased by 11.00 g/l (9.91%). Significant differences in nonspecific resistance indicators were observed in the rabbits from the experimental groups. The phagocytic activity of neutrophils showed a significant increase, reaching levels of 38.79%–39.97%, while the bactericidal activity of blood increased to 50.65% when compared to the control group. The study demonstrated that the probiotic drug “SUB-PRO” effectively enhanced nonspecific resistance indicators. The obtained data indicate improved adaptability and increased body weight in the animals, along with enhanced immunity, after the inclusion of the probiotic supplement in the rabbits’ daily diet after weaning.