Effects of dietary Mango Kernel Meal (MKM) inclusion on growth indices, haemato-biochemical profiles, and growth and immune-regulatory genes of Gibelion catla.

Mango kernel meal (MKM) is an affordable and widely available industrial byproduct, commonly used as an aquaculture feed supplement due to its immuno-physiological properties. This study represents a novel effort to evaluate the dietary effect of MKM on growth, feed utilization, haemato-biochemical attributes, and expression of growth and immune genes in Gibelion catla. G. catla were subjected to four treatments in triplicate (n = 40 fish/replicate), and fed diets supplemented with 0 (control group), 5, 10, 20 g/Kg (T1-T3, respectively) of MKM over a 90-days trial. The results revealed a significant enhancement in the growth indices and reduced feed conversion ratio in the T1 group than control and other treatment groups. Fish fed 5 g/kg MKM had significantly (P < 0.05) higher RBC, Hb, and Hct than the control and other tested diets. Inclusion of MKM at 5 g/kg in the diet significantly reduced haemato-biochemical stress biomarkers (glucose, and cortisol) as well as hepatic transaminase levels. Frequencies of erythrocytes cellular abnormalities (ECA) and erythrocytes nuclear abnormalities (ENA) were higher at 20 g/Kg of MKM inclusion. The relative mRNA expression profile of examined growth and immune-related genes were upregulated at 5 g/kg of the MKM supplementation diet than the control group. The principal component analysis results demonstrated that supplementation with 5 g/kg of MKM significantly improved nutritional and haemato-biochemical parameters. These findings suggest that the inclusion of 5 g/kg of MKM in the basal diet as a dietary supplement for G catla exerts a positive influence on growth performance, and immune-physiological status, highlighting its potential as a beneficial feed additive.