First experience of cultivating african catfish (Clarias gariepinus Burchell, 1822) under natural temperature conditions in water bodies of Polissiya of Ukraine

Abstract

Purpose. Establishing the possibility to cultivate African catfish (Clarias gariepinus) in ponds and pools under water temperature conditions typical for the Polissya region of Ukraine during the growing season. In particular, to compare the efficiency of cultivation in concrete pools and earthen ponds. Also, to compare the effectiveness of using floating and sinking feeds in ponds and pools. Methodology. The study, which lasted throughout the growing season, used African catfish seeds of industrial origin. The study was conducted at the educational, scientific, and production laboratory of fisheries of the National University of Life and Environmental Sciences of Ukraine. The individual weight of the fish seeds, from which four groups were formed, each consisting of 237 specimens, was 6.3 g ± 0.5 g. Experimental groups were formed based on cultivation conditions and feed type. Aller Aqua feeds of two types: floating “Primo Float” and sinking “Master” were used for feeding African catfish. Accordingly, sinking feeds were introduced into the diet of one group stocked in a pool and one stocked in a pond. Floating feeds were introduced into the diet of the other two experimental groups. Water supply was provided by gravity flow from the surface water of the accumulating water body. Findings. The study showed that in terms of survival rate, the pool method using floating feeds was more effective compared to the pond method, where the experimental group fed with sinking feed exhibited better survival. In terms of average individual weight, specimens grown in ponds exceeded those grown in pools. We believe this can be explained by the presence of natural food supply in ponds, which served as an additional source of nutrients for African catfish. The results of this study confirmed the possibility of cultivating African catfish in water temperature conditions typical of the water bodies in the Polissya region of Ukraine, despite wide fluctuations. However, in the case of cultivating African catfish weighing 6.3 g ± 0.5 g under water temperature conditions lower than optimal (24°C), the fish size may not reach marketable levels. In such cases, there is a need to use facilities with closed water supply systems for further rearing of catfish juveniles. Originality. For the first time, a comparison of the efficiency of African catfish (cultivation under the temperature regimes characteristic of water bodies in the Polissya region of Ukraine has been conducted. This comparison was made between concrete pools and earthen ponds, utilizing both floating and sinking feeds. The aim was to determine which cultivation method would result in the highest specific growth rate. Practical value. The results obtained during the study allow expanding technological methods for cultivating African catfish, confirming the possibility of its cultivating under the temperature regime characteristic of water bodies in the Polissiya region of Ukraine. Keywords: African catfish, Ukrainian Polissiya, sinking feeds, floating feeds, growth rate, earthen ponds, concrete pools, industrial aquaculture.