Efficacy of acidified phytase supplemented cottonseed meal based diets on growth performance and proximate composition of Labeo rohita fingerlings

Eficácia de dietas à base de algodão com fitase acidificada suplementada no desempenho do crescimento e na composição proximada de dedos de Labeo rohita

Abstract

The growth of aquaculture sector is strongly dependent upon the continuous supply of inexpensive fish feed with balanced nutritional profile. However, fish meal (FM) is unable to satisfy this demand due to its scarce supply and high cost. In order to test the potential of cottonseed meal (CSM) as a fish meal replacer, a feeding trial of 12 weeks was conducted to check growth performance and proximate composition of Labeo rohita fingerlings. The protein ration of the test feed was satisfied by replacing FM with CSM at 0, 25, 50 and 75%. Sixteen test diets viz., TD₁ (control), TD₂, TD₃, TD₄, TD₅, TD₆, TD₇, TD₈, TD₉, TD₁₀, TD₁₁, TD₁₂, TD₁₃, TD₁₄, TD₁₅ and TD₁₆ were supplemented with citric acid (CA; 0 and 2.5%) and phytase (PHY; 0 and 750 FTU/kg) in a completely randomized design with 3×3 factorial arrangement. The highest weight gain (11.03g), weight gain% (249.21%), specific growth rate (1.39) and best feed conversion ratio (1.20) were recorded by fish fed with TD₁₂. Furthermore, the same level increased the crude protein (59.26%) and fat (16.04%) being significantly different (p<0.05) than that of control. Conclusively, the addition of acidified phytase (CA; 2.5%, PHY; 750 FTU/kg) in TD₁₂ (CSM=50%) led to the improved growth and proximate composition of L. rohita fingerlings.

Keywords:
plant by-products; aquaculture; fish meal; cost-effective feed; body composition