Biochemical blood profile and retinol levels in liver broiler chickens with the use of probiotics

The use of antibiotics in poultry farming creates a number of risks associated with the development of antibiotic resistance in bacterial disease pathogens. Probiotics are a promising direction for replacing traditional antimicrobial agents. The aim of the work was to investigate the biochemical parameters of blood serum of broiler chickens and the content of vitamin A in the liver using commercial probiotic preparations TM Sviteco based on bacteria of the genus Bacillus. The studies were conducted at an industrial broiler breeding enterprise on Cobb 500 crossbred chickens in two poultry houses according to the principle of similar groups. Chickens in the control group were raised using traditional antimicrobial agents (control poultry house). Chickens raised using alternative technology without antibiotics (experimental poultry house) were daily added to the drinking water of Sviteco-PWC tilus at the rate of 200 ml per 1 ton of water. During the periods of vaccination and feed change, the drug Sviteco Mg+pro was added at the rate of 1 l per 1 ton of water. Aerosol disinfection was carried out using Sviteco-Multi daily at the rate of 1–1.5 l per day. Litter treatment was carried out on the 10th day of growing using Sviteco-MBT. Housing and feeding conditions, as well as veterinary treatment, were similar in both poultry houses. All probiotics contained bacteria of the genus Bacillus. Blood samples were collected from 44 day-old clinically healthy chickens (10 samples from each group). After slaughter on the 47th day, 5 livers were taken from control and experimental animals. Determination of biochemical parameters of blood serum was performed using the BA-400 BioSystems analyzer (Spain). The level of vitamin A in the liver was investigated by HPLC. In serum blood of broiler chickens grown with the use of probiotic preparations TM Sviteco, a significantly higher level of total protein was found. An increase in the content of globulin fractions of protein indicates an enhanced immune response. A tendency to reduce the activity of alkaline phosphatase and the content of inorganic phosphorus was found. A simultaneous increase in the level of total calcium is associated with better assimilation of minerals from the digestive tract. Under the action of probiotics in the liver of chickens, an increase in the level of vitamin A was noted. Therefore, the use of probiotic preparations based on Bacillus bacteria stimulates the immune response in chickens and increases the intensity of assimilation of minerals and vitamins from feed. This requires further study of the mechanisms of action of probiotics on the morpho-functional state of the intestine and its immune structures.