Comparative Effects Of Using New Multi-Strain Synbiotics On Chicken Growth Performance, Hematology, Serum Biochemistry And Immunity

Simple Summary Currently, there is an urgent need to decrease the use of antibiotics in poultry production. Long-term use of antibiotics in birds leads to the development of many drug-resistant microorganisms, has a negative impact on the environment and the antibiotic residues in poultry meat pose hazards to consumers' health. Probiotics, prebiotics and synbiotics used in poultry are good alternatives for antibiotic and antibiotic growth stimulants. However, such additives must be adapted to the species, age and intended use of birds. Our newly developed synbiotic formulas which comprised three, four or five strains ofLactobacillussp., as well asS. cerevisiaeand inulin, were administered in feed for meat-type chickens throughout the 42-day experimental period. The results showed that our new synbiotics do not have any unfavorable influence on chicken health and may modulate the immune response and biochemical parameters. The results are very promising, and our synbiotics can be considered as products for commercial use in poultry. However, these findings should be confirmed in future field experiments. In this study, the influence of new multi-strain synbiotics on chicken growth performance, hematology, serum biochemistry and immunity was explored. Each synbiotic preparation (A, B and C) comprised three, four or five strains ofLactobacillussp., respectively, as well asS. cerevisiaeand inulin. All strains used in the synbiotics originated from wild-type strains from animal farms in Poland. Six groups of chickens, ROSS 308 line, were fed with three different synbiotics at a dose of 0.5 g/1 kg of feed. Body weight, as well as the biochemical and hematological parameters of the animals in each study group, were determined on the 7th, 14th, 28th and 42nd day of life. Body weight on day 42 differed between groups and was the highest in control group. This group also had the highestfeed conversion ratio (FCR) value. All measured biochemical parameters were in the normal ranges for poultry; however, we observed a lower alkaline phosphatase (AP) concentration on day 7 in the groups fed with synbiotics, which correlated with a lower level of triglycerides in those groups. The aspartate transaminase (AST) concentration was significantly lower in all groups on day 42 in comparison with the control. On day 7, the control group showed the highest concentration of Ca, K and P. Other parameters did not differ significantly throughout the experiment. All groups showed a similar tendency of increase in the red blood cells (RBC) count according to the age of the birds. Every white blood cells (WBC) population showed differences in the proportions between T and B lymphocytes. The T cell and monocyte counts increased until day 28 in all groups. The results showed that our newly developed synbiotic formulas do not have any unfavorable influence on chicken health and may modulate immune response and biochemical parameters. However, this hypothesis needs to be evaluated in future experiments.