Effects of probiotic doses and stocking density on water quality and some growth performances of Clarias gariepinus fingerlings

Title : Effects of probiotic doses and stocking density on water quality and some growth performances of Clarias gariepinus fingerlings

Abstract:

Stocking density is a very important factor in aquaculture. In African catfish (Clarias gariepinus), high densities often lead to a deterioration in water quality, slower growth, and increased mortality. This study, conducted from April 20 to June 20, 2025, at the Grenier d'Afrique farm (Nkolnda, Yaoundé), aimed to evaluate the effect of probiotics on water quality and growth performance of fry raised at different stocking densities. A total of 2,160 fries (1 ± 0.3 g) were divided into three treatments: 0 g/m³ (control), 3 g/m³ and 5 g/m³ of the probiotic AQUAcare (Skretting), containing Bacillus subtilis, B. amyloliquefaciens, B. pumilus, and B. licheniformis. Each treatment was applied at three densities (2, 4, and 6 fry/L) in duplicate. After 60 days, NO?? concentrations did not vary significantly (p > 0.05), while NH?? concentrations increased significantly with density (p < 0.05). The best zootechnical performance was recorded with 3 g/m³ at 2 fry/L: weight gain (63.70 ± 3.67 g), average daily gain (1.06 ± 0.06 g/day), survival rate (88.33 ± 2.35%), and feed conversion ratio (1.33 ± 0.11). The highest specific growth rate (SGR) was observed with 5 g/m³–2 al/L. However, the high-density dose of 5 g/m³ (6 al/L) generated the highest production cost (2,846.40 CFA francs/kg) and negative profitability. Thus, the application of 3 g/m³ of low-density probiotics improves growth and survival, while moderate density optimizes profitability.

Keywords: Clarias gariepinus, probiotics, growth performance, water quality, stocking density, profitability

Biography:

Dr. Arlette Noël NDJUISSI TAMKO is a Lecturer-Researcher at the University of Douala, National Higher School of Agronomy, Halieutic and Veterinary Medicine, Cameroon. She holds a PhD in Marine Science, specializing in Aquaculture, Fish Health and Pathology, from Ningbo University, China, and an MSc in Applied Ecology with a focus on Parasitology from the University of Dschang, Cameroon. Her research interests include fish nutrition, fish health and pathology, fish diseases, microbiology, and sustainable aquaculture. Her research focuses particularly on the use of natural feed additives and alternative nutritional strategies to improve fish growth, feed utilization, health, and production performance. She has published research on dietary supplementation and feed ingredients in African catfish and other cultured fish species. At WAC 2026, she will present her research entitled “Diet Supplementation of Cyprinus carpio with Garcinia kola Seed Powder: Effect on Productive Performance and Body Composition.”