Effects of Fermented Rice Bran-based Copefloc Technology Supplemented with Mixed Microalgae (Chlorella vulgaris and Aphanizomenon flos-aquae) on Growth Performance, Digestive Enzyme Activity and Water Quality of Indian Spiny Loach (Lepidocephalichthys thermalis)

Indian spiny loach, Lepidocephalichthys thermalis, is an economically important freshwater ornamental and food fish with high nutritional value and market demand. However, limited information is available regarding its captive culture. Hence the present investigation was undertaken to assess the impact of groundnut oil cake (GNOC) with mixed algae (Chlorella vulgaris and Aphanizomenon flos-aquae) + fermented rice-bran (FRB) (1:5, 1:6, 1:7, 1:8, 1:9 and 1:10) on growth ratio, digestive enzyme activity and water quality of Indian spiny loach under captive culture conditions.

The study followed a completely randomized design (CRD) with six treatments and a control each in triplicate tanks. Juvenile Lepidocephalichthys thermalis were stocked at a rate of 50 numbers in all 21 experimental tanks. Groundnut oil cake (GNOC) at 8% body weight and mixed algae of 250 ml was fed to all experimental tanks throughout the rearing period. Once in a week, the fermented carbon source at various ratios (1:5, 1:6, 1:7, 1:8, 1:9 and 1:10) was added to the respective treatment tanks at a rate of 3 ml L^-1.

The study displayed significant variations (p<0.05) in growth, digestive enzyme responses and water quality among the experimental groups of Lepidocephalichthys thermalis reared indoor. From the outcome of the study, groundnut oil cake (GNOC) with mixed algae (Chlorella vulgaris and Aphanizomenon flos-aquae) + fermented rice-bran (FRB) (1:5) produced the best overall culture performance and digestive enzyme activity of Lepidocephalichthys thermalis and maintain better water quality.