The study investigated the effects of carotenoid-rich ripe papaya Carica papaya pulp powder supplementation on the growth and pigmentation of commercially important indigenous ornamental fish species mottled loach Paracanthocobitis botia. During a 90-day feeding trial, fish were fed diets fortified with papaya pulp powder at a rate of 6 g per 100 g of feed. The experiment was conducted in eight 57-liter aquariums, each one stocked with 15 age-matched male fish and fed at a rate of 2% of their body weight daily. Total carotenoid content (TCC) in fins, skin, and muscle was measured spectrophotometrically at 30-day intervals. TCC (µg/g) values were significantly higher (p < 0.01) in the papaya pulp powder supplemented group compared to the control. TCC in fish receiving the papaya-enriched diet was 6.55 µg/g in fins, 7.89 µg/g in skin, and 1.33 µg/g in muscle. Ripe papaya pulp as an effective natural source of carotenoids for enhancing coloration and growth performance could induce morphological coloration in indigenous ornamental fish P. botia, offering a sustainable option for the ornamental fish industry.
The growing interest of millennials in colorful aquarium ornamental fish as a symbol of a luxurious lifestyle is expected to remain a key factor driving industry growth. Furthermore, pigmentation agents are essential for boosting the vivid colors of ornamental fish, which play a crucial role in their market value and attractiveness to consumers.