Impact of banana peel and cocoa husk on growth performance, microbial communities, and skin pigmentation in goldfish (Carassius auratus) and Thaila (Catla catla)

Carassius auratus and Catla catla are polyculture species where growth and intensification have adverse effects on water quality, raising the risk of infection and disease prevalence. Due to these factors, the survival rate of farm fish is reduced. The demand for aquaculture continues to rise with human population growth, emphasizing the importance of well-formulated feeds in aquaculture success. High-quality feed can be prepared using industrial byproducts. It leads to minimizing feed expense, controlling disease outbreaks, and increasing net profit. This research work was conducted to study the impact of banana peel and cocoa husk on growth, microbial community, and pigmentation in C. catla and C. auratus. For this purpose, 30 specimens each of C. catla and C. auratus were randomly assigned to three groups: control (T0) and experimental (T1 and T2). T0 received commercial feed, whereas T1 and T2 were fed banana peel and cocoa husk diets at 2% body weight, respectively. For statistical analysis, a 2-factor factorial under CRD was performed. In the experimental group, length, weight, and specific growth rate (SGR) were non-significant between the species, but showed significant differences compared to the control group. In comparison to the control group, the bacterial count and pigmentation in the experimental group were significant. Because of their carotenoids and antioxidant qualities, banana peel and cocoa husk increased both species' immunological responses and pigmentation. Finally, integrating banana peel and cocoa husk into the diet of C. auratus and C. catla holds potential benefits in terms of reducing intestinal microorganisms, improving growth, and enhancing pigmentation of the fish species.