Hematological and biochemical composition of the blood of broiler chickens when using a biologically active supplement during vaccination

The Department of Veterinary Medicine for Agricultural Poultry at the Omsk Agricultural Research Center conducted a study to evaluate the effect of a dietary supplement based on essential oils on the hematological and biochemical parameters of the blood of domestic cross broiler chickens against the background of vaccination, which was used as a model stress factor. To conduct the study, two groups of 70 heads each were formed from day-old young animals. The rearing period was from one day to 38 days of age. The control group representatives received clean water, and in the experimental group, a biologically active supplement was added to the water at a dose of 0.2 ml/l during the first 7 days, then from the 8th to the 38th day – at a dose of 0.3 ml/l. At the age of 9 days, clinically healthy broiler chickens were vaccinated against Newcastle disease with the live vaccine "La Sota" (intranasally, according to the farm's schedule). The vaccine was administered to the chickens using a pipette, one at a time, in both nostrils at a volume of two drops, while the other nostril was closed with a finger to ensure deeper penetration of the vaccine into the nasal cavity. Hematological and biochemical blood tests were performed the day before vaccination, as well as 4 and 19 days after vaccination and at the end of the experiment. It was established that the biologically active supplement contributed to an increase in the amount of total protein in the blood serum by 18.3–20.9%, albumin by 13.8–23.3%, globulin by 19.7–22.3%, uric acid by 4.5–6.9%, and the albumin/uric acid ratio by 1.2–2.0 times, which indicates an improvement in protein metabolism in the bird's body. In addition, an increase in the content of erythrocytes by 13.0–37.5%, hemoglobin by 10.4–22.6%, and leukocytes by 9.0–56.8% was noted, which contributed to the saturation of blood cells with oxygen and a positive effect on the natural resistance of the chickens' body.