EFFECT OF VITAMINS A AND B6 ON AQUACULTURAL AND BIOLOGICAL PARAMETERS OF YOUNG-OF-THE-YEAR KOI (CYPRINUS CARPIO KOI)

Purpose. To study the effect of vitamins A (retinol) and B6 (pyridoxine) on aquacultural and biological parameters of young-of-the-year koi (Cyprinus carpio koi). Methodology. The study was conducted in laboratory conditions based at the Bila Tserkva experimental hydrobiological station of the Institute of Hydrobiology of NAS of Ukraine in 2015. To achieve the objectives of the research, we used morphometric analysis methods. We performed the studies of the variable-based changes of the basic morphological and biological parameters of young-of-the-year koi carp koi under similar culture conditions. To perform the work, we used four groups of young-of-the-year koi carp with mean initial weight of 1.4±0.07 grams at the age of 30 days with the same number of individuals (25 fish) in each group. One group was the control group (group 1), while three others were experimental groups, which were fed by starting compound feeds supplemented with vitamins A and B6. We examined and compared the effect of powdered water-soluble vitamin B6 with 99.0% weight content of pyridoxine hydrochloride, as well as a complex of vitamins A and B6, encapsulated in polymeric carriers on biological parameters of fingerlings of young-of-the-year koi carp. Findings. The study results showed that the addition of pyridoxine and retinol to fish feed significantly improves the survival rate of young-of-the-year koi carp by 12.0% and 16.0% respectively. We detected the general positive effect of experimental vitamin supplements, particularly of two forms of vitamin B6 on survival and weight, total body length, standard body length and the largest body height of young-of-the-year koi carp. However, for the majority of the studied parameters of fingerling weight and length, the best performance was observed when using vitamin B6, encapsulated in polymeric carriers. Originality. The aquacultural and biological parameters of young-of-the-year koi carp after feeding them with feeds supplemented with vitamin A and various chemical forms vitamin B6 have been studied for the first time. Practical value. Improvement of the survival rate and mean weight of koi carp seeds. The increase of the total body length, standard body length and the largest body height of younf-of-the-year koi carp.