Abstract
The article highlights the experience of using the preparation Biocons and its effects on the physiological status of fish, its liver, gills and muscles. The results of the comparative analysis of muscle tissue showed that muscle reactions in both control fish and experimental fish have a whole spectrum of similar destructions. The use of domestic production feed with and without probiotic Biocons does not have a toxic effect on the liver structure. Therefore, the feed is safe for rearing fish. The purpose of the work is to justify experimentally the effectiveness of using the probiotic preparation Biocons as an additive in feed. The research tasks were set: experimental rearing of rainbow trout fry using various feeds, as well as feed with Biocons; conducting a comparative analysis of the results of rearing trout juveniles on various feeds, as well as feeds with Biocons as applied to farming and biological parameters; identifying the effect of various feeds on the physiological state of rainbow trout juveniles, their liver, muscles and gills. According to the research results based on the comparative analysis of the impact of three types of experimental starting and production artificial feed (feed without probiotic; feed with Biocons probiotic made in Kazakhstan and imported feed by AllerAqua, Dane) on the fish-breeding and biological indicators of trout juveniles and fingerlings it has been found that good results were obtained when using all of the above mentioned feeds.