Effect of spirulina and apple peel meal on growth performance, body composition and total carotenoids of snow trout (Schizothorax richardsonii)

Effect of spirulina (Spirulina platensis) and apple (Pyrus malus) peels on growth performance, body composition and total carotenoids of Schizothorax richardsonii was exposed with a sixty-day experiment and two hundred seventy fingerlings (9.19 ± 0.29g) by random distribution (10 fish in each tank) into nine treatments in triplicates. Nine isonitrogenous (35.25 ± 0.9% crude protein) diets were prepared with graded levels of either spirulina (SP) or apple peel (AP) meal. Treatment groups were T₀ (control), T₁ (3%SP), T₂ (5%SP), T₃ (7%SP), T₄ (10% SP), T₅ (3%AP), T₆ (5%AP), T₇ (7%AP) and T₈ (10%AP). The effects of SP and AP meals on S. richardsonii were assessed in terms of growth parameters, carcass nutrient composition and total body carotenoids. Growth parameter for the fishes fed on different diets varied significantly for T₂, T₃ and T₄, non-significant for the entire apple peel fortified diets. FCR reduced from 2.52 (T₀) to 1.19 (T₃ and T₄) with an increase in spirulina percentage in the diet. Supplementation of spirulina meal had the potential to enhance the coloration, body composition and growth of Schizothorax richardsonii, while apple peal meal also has impact on all the parameters except growth. Spirulina and apple peel meal at 5–10% supplementation of the diet provided highest carotenoid accumulation in the flesh among the groups which may help farmers as well as other stakeholders in realizing more profits in the culture of this species.