The effect of different doses of probiotic feed additives on hematologic indices and morphological structure of individual pig internal organs

In order to improve the digestibility and absorption of feed, metabolic processes, growth and development of animals, increase the resistance of the body immunomodulatory agents, probiotics, prebiotics, combined enzyme-probiotic feed additives are widely used. The purpose of our work was to conduct comparative clinical trials of the effectiveness of the probiotic feed additive Probion-forte in terms of productivity, blood indices and histological structure of individual internal pigs organs during fattening. The researches were carried out on 120 piglets of big white breed at the age of 28 days, which were divided into 4 groups with 30 units in each one. The probiotics were added to feed in different concentrations in order to determine their efficiency and examine influence on piglets organism: the first group was given probiotic Probion-forte in dose of 1.0 g/kg (10 weeks); the second one – Probion in dose of 1.0 g/kg (6 weeks) and 0.5 g/kg (4 weeks); the third one was given probiotic Bio Plus 2B in dose of 0.4 g/kg for 10 weeks; and the fourth one was a control group. The compound feed was provided according to norms recommended for big white breed taking into account age. On the 42nd day (6 weeks) and on the 70th day of test 10 units were selected for haematological, pathomorphological and microbiological tests. The productivity of animals of all studied groups was evaluated by the average daily gains, safety, feed conversion and slaughter output. The stabilized with EDTA piglets’ blood was used for morphological studies, and blood serum – for biochemical studies. The clinical trials have shown that the application of Probion-forte, as a feed additive for fattening of piglets within 10 weeks after weaning, did not cause adverse reactions, was well tolerated by animals and contributed to the improvement of the processes of erythropoiesis and leucopoiesis, increased of serum total protein content. The increasing activity of serum transaminases indicated more intense metabolic processes in experimental animals’ organism, which was confirmed by increase in average daily weight gains and slaughter output compared to control. In the microscopic examination of the thymus, spleen, lymph nodes, intestines, liver, the characteristic histological structure of the organs was preserved and indicated their active morphofunctional state throughout the study period. Morphometrically the increase in the height of the villi in the duodenum and the size of the thymus lobes in piglets, which were fed with probiotic feed additives was established. The efficiency and appropriateness of the application of these products was confirmed in the first and second experimental groups. However, the most significant difference was observed in piglets fed with Probion-forte for 10 weeks at a dose of 1.0 g/kg of feed.