This work aims to study the elemental status of dog hair in ontogeny. The studies were conducted on animals 2–4 and 8–10 years of age. Under observation were 39 dogs of the following breeds: Rottweilers, Dalmatians, Black Terriers, Golden Retrievers, Labradors and Dobermans. The animals were born and kept in Novosibirsk, Tomsk, Yalta and Moscow. The dogs were kept in apartments with obligatory morning and evening exercise. Wool was sheared from the withers to determine the concentration of bioelements. The bioelemental composition of wool was determined on an Elan 9000 quadrupole mass spectrometer and an Optima 2000DV atomic emission spectrometer by inductively coupled plasma mass spectrometry and inductively coupled plasma atomic emission spectrometry. The research was carried out during the summer period. The diet of dogs consisted of dry industrial feed, balanced in terms of essential nutrients, vitamins, and macro- and microelements. In the research process, specific microelementoses were found in dogs of different ages. The obtained results showed that dogs of 2-4 years of age exceed 8-10-year-old animals in the concentration of aluminium in wool by 81.3% (P<0.01), chromium - by 67.1 (P<0.001), copper - by 27.4 (P<0.05), iron - by 81.7 (P<0.05), mercury - by 70.5 (P<0.05), iodine - by 68.3 (P< 0.05), potassium – by 57.5 (P<0.01), lithium – by 65.7 (P<0.05), lead – by 84.5 (P<0.05), vanadium – by 56.6 (P<0.05) and zinc by 27.9% (P<0.01). At the same time, in the group of 2-4-year-old animals, the iodine level exceeded the limit of reference values by 35.5%. On the other hand, in dogs of 8–10 years, chromium, iron, iodine, manganese, and silicon indicators have lagged behind the lower limit of the reference values by 45.0, respectively; 89.9, 86.0, 91.0 and 89.7%.

The paper presents data indicating the possibility of correction of endocrine and metabolic status in dogs with euthyroidism homogenate from larvae of drones. It is shown that the daily intake of homogenate at the rate of 15 mg per kg of body weight for two months contributes to the increase in the blood levels of thyroxine, testosterone, red blood cells, hemoglobin, total protein, globulins and leukocytes.

In order to study the effect of the drone homogenate on the elemental, metabolic, hematological, and immune statuses of dogs, we created control and experimental groups of Labrador retrievers. The dogs were kept in the conditions of apartments in the village of Kochenevo, Novosibirsk Region. The diet of animals consisted of meat, cereal porridge, cottage cheese and vegetables. Dogs received daily vitamin and mineral supplements and apples. Labradors – retrievers of the control group daily, for two months, drone homogenate was drunk once a day at the rate of 15 mg per kg of body weight. The results of the studies showed that in the presence of a drone homogenate, dogs increase thyroxin synthesis, activate erythro and leukopoiesis, increase phagocytic activity and phagocytic index, synthesis of total blood protein, in particular globulins, and triglyceride levels. An analysis of the chemical composition of blood serum carried out before the start of the experiment revealed in dogs of both groups more or less pronounced microelementoses in terms of cobalt, chromium, iron, potassium, manganese, sodium, phosphorus, lead, selenium and zinc. After completion of the course of taking the homogenate, a correction of the macro- and microelement composition of the blood occurred. The concentration of lithium, chromium, sodium, iron, phosphorus was statistically significantly reduced, and the concentration of boron, calcium, copper, iodine, nickel and tin increased.

The presented data reflect the bio-element status of the coat of Novosibirsk dogs with different types of feeding. The authors studied two groups of animals kept in apartments with a double active exercise. The first group of dogs received dry food balanced with essential nutrients, and the second group received meat, porridge, and vegetables. Results showed that dogs on a natural diet had cobalt and chromium levels below the reference values. On the other hand, dogs whose diet consisted of dry food had a more balanced bioelement composition of the coat. The exceptions were arsenic, iodine, and strontium, whose values exceeded the limit of the physiological norm.

The problem of the formation of leukemoid reactions in cattle is considered. It is noted that such changes in the morphological composition of blood are most often characterized by a decrease in the quantitative content of lymphocytes while increasing the concentration of microphages (neutrophils). With the elimination of the cause that caused the manifestation of the leukemoid reaction of the blood, the morphological composition of the peripheral blood is restored to normal.