Effect of Kappaphycus and Gracilaria SAP as feed supplement on growth performance, survival, biochemical composition and disease resistance in Labeo rohita (Hamilton, 1822)

Abstract

The present study evaluated the effects of dietary supplementation of Kappaphycus and Gracilaria SAP on growth performance, survival, biochemical composition and disease resistance of Labeo rohita (Hamilton, 1822). Two independent feeding trials were conducted using isonitrogenous diets (30percent crude protein), comprising a control diet (without SAP.) and four experimental diets supplemented with 5 percent, 10 percent, 15 percent and 20 percent SAP. of Kappaphycus or Gracilaria. Growth performance, feed utilization, hematological parameters, antioxidant enzyme activities, and resistance against Aeromonas hydrophila were assessed over a 60-day culture period. Fish fed with 20 percent Kappaphycus sap exhibited significantly improved growth performance, survival and enhanced disease resistance compared to the control and other treatments. The results further indicated increased antioxidant and antimicrobial activity with higher inclusion levels of Kappaphycus SAP., highlighting its potential as a functional feed additive in aquaculture. In the Gracilaria sp. trial, the highest growth performance, specific growth rate (SGR), protein efficiency ratio (PER), survival rate, and lowest feed conversion ratio (FCR) were recorded in fish fed with 10 percent sap. supplementation, and disease resistance were observed at 20 percent inclusion. Overall, the findings suggest that dietary inclusion of Kappaphycus and Gracilaria SAP at appropriate levels can effectively enhance growth, survival and disease resistance in L. rohita, thereby supporting their application as natural functional feed supplements in carp aquaculture.