Dietary Supplementation of Black Pepper (Piper nigrum) Enhances Growth Performance and Hematological Parameters in Fingerling Spotted Snakehead (Channa punctatus)

Aquaculture nutrition plays a pivotal role in optimizing fish growth and health, with feed additives increasingly explored for their growth-promoting and immunostimulatory effects. This study investigated the effects of dietary black pepper (Piper nigrum) supplementation on growth performance, feed utilization, and hematological parameters in fingerling Channa punctatus. Six iso-nitrogenous (45% crude protein) and iso-energetic (18.40 kJ/g) experimental diets were formulated with varying black pepper levels (0%, 0.2%, 0.4%, 0.8%, 1.6%, and 3.2%). Fish (initial weight: 8.82 ± 0.5 g) were stocked in 70-L tanks with a continuous water flow-through system (1–1.5 L/min) and fed twice daily to satiation for eight weeks. Results indicated that dietary black pepper at 0.4% significantly enhanced absolute weight gain (AWG), specific growth rate (SGR), protein retention efficiency (PRE), and protein gain (PG), while reducing feed conversion ratio (FCR). Beyond 0.4%, growth performance declined, likely due to reduced palatability and feed intake. Carcass protein content improved with 0.4% supplementation, whereas moisture, fat, and ash remained unaffected. Hematological parameters, including hemoglobin, red blood cell count, and hematocrit, also peaked at 0.4% inclusion, indicating improved oxygen transport and metabolic efficiency. These findings suggest that black pepper, particularly at 0.4% dietary inclusion, enhances growth, nutrient utilization, and hematological health in C. punctatus. The study highlights the potential of black pepper as a natural growth promoter in aquaculture, offering an eco-friendly alternative to synthetic additives while supporting sustainable fish farming practices.