Abstract
Background Nile tilapia (Oreochromis niloticus) is a promising fish species for fish farming development in the Republic of Kazakhstan. It exemplifies a balanced and fast-growing source of flesh for future food production. In this context, optimising breeding methods is crucial for a high flesh yield and a safe product. The study delves into the potential of the Enterocol drug in enhancing Nile tilapia breeding, focusing on assessing muscle state and blood parameters. Objects Two groups of fish were utilized, with 20 specimens in each group. One set was the control group, and the other was the experimental group. The single difference between the fish groups was the Enterocol consumption by the experimental specimens, which were given an E. coli 64G strain concentration of 108 CFU in mL and a 5% daily dose of fish body weight three times daily for two months. Methods Blood parameters were analysed to assess the health of the fish groups. Subsequently, classical pathological methods were employed, such as macroscopic and microscopic assessments of each group's fish material. A histological analysis was also performed to assess the condition of the muscles. Results Examining the experimental group's muscles revealed a significant average increase in fish mass and 6.74% total body weight growth. Moreover, the total thickness of the muscle layer decreased as villi height increased, indicating a clear fibre structure. Haematological analysis unveiled elevated levels of haemoglobin, erythrocytes, leucocytes, and total protein in the experimental fish group, indicating improved health. These findings underscore the potential of the Enterocol drug in enhancing fish health and productivity. Conclusion Based on the results, it can be concluded that using Enterocol in fish breeding plants can effectively enhance flesh quality and safety, providing a secure and reliable solution for the aquaculture industry.