ВЛИЯНИЕ ЛЕЧЕБНО-ПРОФИЛАКТИЧЕСКОГО ПРЕПАРАТА ЭС-2 НА ФУНКЦИОНАЛЬНОЕ СОСТОЯНИЕ ГИБРИДА ТИЛЯПИИ OREOCHROMIS SPP

Abstract

The articlestudies the influence of treatment-and-prophylactic specimen ES-2 (extract of sapropel) onto the fish-breeding, biological and physiological-biochemical parameters of eugamic tilapia hybrid species Oreochromis spp. carried out in the Innovative centre "Bio-Aquapark - Scientific and Technical Center of Aquaculture" of Astrakhan State Technical University. Fishes (in the amount of 15 species) were kept in aquariums with water volume of 20 litres with artificial aeration, filtration and heating. High density of seeding facilitated studying the influence of specimen on the degree of fish resistance to water environment pollution by waste products. In the course of the experiment (30 days) parameters of the water environment (temperature, pH, content of oxygen, nitrites, free ammonia) were under control. According to the results, all fish-breeding and biological parameters were better among fish species from the pilot group, which got food including sapropel extract. Survivability of fish under experiment made 100%, of those under control - 87%. The absolute increase in body mass of fish in the experimental group (28.83 g) was by 5.06 g higher than in control group. The average daily gain was also higher in fish from the experimental group and amounted to 0.96 g while in the control group it was lower - 0.79 g. Feed conversion ratio in experimental group was lower (1.2) than in control group (1.3), which shows better assimilation of feed by fish species from the experimental group. Concentration of hemoglobin in fish species of both groups differed lightly, but in experimental group it was higher: 90.0 ± 1.81 g/l; in the control group it was 88.32 ± 1.76. In the experimental group there was observed the rise in erythrocyte sedimentation rate that might indicate a change in protein composition of blood plasma due to better nutrition, and can also be a result of acclimation of tilapia to another diet). However, the level of total serum lipids slightly changed: experimental group - 3.41 ± 0.15, control group - 3.46 ± 0.13 g/l; cholesterol level changed within 3.5-3.53 mmol/l, i.e. dynamics of lipid exchange enhanced normal exchange of energy resources. According to the study results, specimen ES-2 is recommended to add to the production food in the course of commercial breeding of tilapia.