Influence of a diet containing plant ingredients at different levels on growth performance, carcass biochemical composition, and blood parameters in Indian major carps grown in polyculture earthen ponds.

The effect of feeding levels of plant ingredient-based diet on growth, body composition, and serological constituents of Indian major carps was determined in pond culture condition. Juveniles of Indian major carps (IMCs), Catla catla (catla, 65.87 ± 2.45 g), Labeo rohita (rohu, 64.67 ± 2.15 g), and Cirrhinus mrigala (mrigal, 39.58 ± 3.49 g) were fed 1%, 1.5%, 2%, and 2.5% of the body weight for a period of 150 days. At the end, the total production was significantly higher at 2.0% feeding level and did not change thereafter. The nutrient utilization parameters were significantly (P < 0.001) affected by the feeding level and decreased both linearly and quadratically with the higher level of feed. The SGR in terms of wet weight, dry weight, protein, and lipid increased up to 2% feeding level and plateaued thereafter. The whole body crude protein content of all the three species was the lowest at 1% feeding level and the whole body lipid content increased with increased feeding levels. Tissue protein gain and lipid gain of IMCs were the highest at 2% feeding level. Blood parameter did not indicate any disease or stress condition due to feeding treatments. Considering the growth and nutrition utilization and health of fish, it can be concluded that optimum feeding level of all plant ingredient-based feed of IMC could be 2% of the body weight in pond culture condition.