The article presents the data on the morphofunctional state of the liver in the broodstock of the common carp (CYPRINUS CARPIO) during the spawning period. The research was carried out on one of the farms in the Voronezh region that specializes in the breeding and rearing of commercial fish. The broodstock under investigation was divided into two groups according to the age indicator. The first group (n=6) (the main stock) was formed by individuals weighing 4-7 kg, aged 4-7 years; the second (n=6) – individuals of 8-17 kg, aged 7 years and older. When studying the biochemical indicators, the following changes were revealed: direct bilirubin in the second group exceeded the normative values by 62.3%. In the first group the ALT level was 62% higher than the specified norm, and in the second group – 85.2%, respectively. The change in the alkaline phosphatase index in the first group was lower than the standard indicators by 74.3%, in the second group – by 59.6%. Glucose in the first group exceeded the norm by 87.3%, in the second group – by 71.2%, respectively. The histological and cytological studies carried out made it possible to confirm the presence of hepatosis in the liver of broodstock in all the studied groups.

Bovine respiratory diseases are widespread and present a multifactorial and variable etiology. However, several aspects of their origin remain understudied. Therefore, the objective of the present study was to investigate the effect of changes in calves’ keeping conditions on their clinical state in terms of microbiocenosis in their respiratory tract. The study was conducted in the winter season, with 37 healthy calves, 5-6 months in age, which were transferred from calf barn number 1 with favorable conditions to calf barn number 2 having a similar design as that of the previous barn but with unfavorable microclimatic parameters (drafts, low temperature, and high humidity). Within 7-9 days after their transfer to the other barn by a veterinary specialist, 54.1% of the calves were diagnosed with catarrhal bronchopneumonia. On day 10, all animals were slaughtered and dissected. Mucus samples for bacteriological analysis were obtained from the mucous membrane of seven sections of the respiratory tract of animals. In all calves, the highest degree of contamination was observed in the first half of the ventral nasal passage (84.9 ±24.46% in healthy calves and 85.7 ±18.55% in sick calves). In healthy calves, the degree of contamination in the front of the choanae was lower by a factor of 56.2% (P = 0.000059) compared to sick calves, and this value continued to decrease when moving toward the lower respiratory tract until the complete disappearance of the bacteria.

The article presents the results of studying changes in hematological and biochemical indicators in pregnant sows during different gestation periods on an industrial pig breeding farm. It has been established that more pronounced changes are noted with an increase in the duration of gestation and are manifested by a decrease in the serum content of erythrocytes, hemoglobin, color index (globular value), platelets, albumins, iron, an increase in hematocrit, ESR, globulins to maintain balance in the hemostasis system.

The article presents the results of studies on the subchronic toxicity of recombinant interferon-λ on Holstein cows. The animals of the first group served as the control, the cows of the second group were intramuscularly injected with the test drug at a therapeutic dose of 10.0 ml 1 time per day for 9 days. The potential toxic effect of recombinant interferon-λ was assessed by indicators of the physiological condition of animals (body temperature, pulse, number of respiratory movements and rumen contractions), as well as by morphological and biochemical blood indicators obtained before the experiment and a day after the last administration of the drug. It has been established that repeated administration of recombinant interferon-λ at a therapeutic dose does not have a negative effect on the clinical indicators of the cows' organism, morphological blood composition and basic metabolic indicators.

The article presents the material on studying the efficacy of the new drug proovulin for the treatment of cows with follicular cysts. It was established that the double administration of proovulin, containing granulocyte-macrophage colony-stimulating factor (GM-CSF), at a dose of 10.0 ml with an interval of 4 days, is accompanied by an efficacy of 83.3% that is by 3.3-8.3% higher, compared to the dose of proovulin of 5.0 ml and surfagon, while reducing the period from calving to fertilization by 18.9-35.7 days and the fertilization rate - by 0.29-0.45. The restoration of the functional activity of the genital gonads in cows with follicular cysts when using proovulin occurs against the background of the normalization of their hormonal-cytokine profile that is manifested by an increase in progesterone production by 10.0 times, which leads to a decrease in the level of TNFα by 20.1%, as well as the concentration of IL-1β - by 18.9%.