52 MARCH 2024 • WORLD AQUACULTURE • WWW.WAS.ORG led to a severe decline in its stocks in recent decades. For instance, along the river stretches of Bhagirathi in West Bengal, its landings have plummeted by 70 percent over the last decade. As of now, it holds the status of “near threatened” on the IUCN list. To promote public awareness and conservation, the Indian state of Uttar Pradesh declared it their ‘state fish’ in 2007. Recognizing its potential, the National Bureau of Fish Genetic Resources (NBFGR) in Lucknow has assigned C. chitala immediate priority for captive cultivation in India. Captive cultivation serves a dual purpose: it introduces a new candidate for aquaculture diversification in India and neighboring countries, and it aids in developing high-quality broodstock for captive breeding and the restocking or ranching of natural water bodies with hatcheryproduced seeds. Captive Breeding and Seed Production Like many other tropical food fishes, this species can be induced to breed during the months of June and July by injecting inducing hormones such as OvaprimTM, OvatideTM, Wova-FH, etc. Male fish attain maturity in 2+ years, while female fish attain maturity in 3+ years. In most cases, female fish are larger than their male counterparts, with a size at maturity of 81-90 cm and 4-5 kg for females, and 3-4 kg for males. In pond conditions, these fish require proper feeding with balanced diets for 3 to 4 months before induced spawning with the onset of the breeding season. They respond well when fed with prawns, trash fish, mussel meat, rice bran, and mustard oil cake (2:1) at 4 to 5 percent of their body weight, 2 times a day. Sexual dimorphism is distinct in male and female fish during the breeding season only. The abdomen of female fish is bulkier than that of males, and no marked coloration is found at the base of their fins. Furthermore, the urinogenital papilla in females is stouter, more fleshy, broader, and less pointed when compared to male fish. An artificial breeding pool can be prepared within the pond ecosystem where fish are being reared by fencing off a portion of the pond with a net. For successful breeding, a male to female ratio of 2:1 should be maintained. The required dose of inducing agents1 for their breeding is 0.5-1.5 mL/kg of body weight. Distinct courtship and spawning behavior are noticeable in these fish after hormonal injection; they start spawning 14-15 hours after injection. The color of the eggs is initially milky white, later turning light yellowish, then yellow-orange, and finally bright orange-red within 6-7 days. The fecundity of these fish ranges from 8000 to 18,000 for individuals with body weights ranging from 1.5 to 2.5 kg. The fertilization rate varies between 50 and 80 percent. The fertilized eggs are large (4 to 4.5 mm) and adhesive, thus it is necessary to provide a hard substrate in the breeding pool to ensure the eggs remain attached. The eggs hatch 165-195 hours after fertilization, with a hatching success rate of 40-50 percent. The newly hatched larvae are light brownish in color, with a size of 10 mm and a weight of 0.05g. The yolk sac remains for a period of one to two weeks. Hatchling survival varies between 40 and 65 percent. During the early life stages, this fish can be fed with plankton, insects, mollusks, shrimp, minnows, and tender roots of aquatic weeds. As they mature, they become carnivorous and predatory. At that time, they require specialized feeding or rearing strategies to ensure proper growth and survival (Fig. 2). Grow-out Production: Challenges and Prospects The farmers from Northeast India, especially from states like Tripura and Assam, show significant interest in chital farming because of its high market demand and its adaptability to ponds where carp culture is not feasible. However, related to the lack of seed and dedicated information on grow-out production techniques, the fish has struggled to flourish within Indian aquaculture production systems. While some information exists on chital reproductive biology, captive breeding, early embryonic and larval development, growth, fecundity, climate change vulnerability, density-dependent growth performance, feed requirements and feeding rate, these pieces of information are fragmentary and sparse. Consequently, they provide limited assistance in integrating chital fish into mainstream aquaculture practices. A crucial prerequisite for successful chital farming is to establish a consistent supply of high-quality seeds. Additionally, because of its predatory nature and self-stocking behavior, integrating chital with carps presents a formidable challenge. As a result, successful chital cultivation demands dedicated production systems with a focus on FIGURE 2. Seeds of Chitala chitala produced in ICAR farm
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