GENETIC IDENTIFICATION AND INDUCED BREEDING OF THREATENED INDIGENOUS SPECIES, Channa striata (Bloch, 1793) FOR SEED PRODUCTION

Abstract

Channa striata, commonly known as the striped snakehead, is a high-value freshwater species with significant aquaculture potential in Bangladesh and Southeast Asia. However, its natural populations in Bangladesh are declining due to habitat degradation, overexploitation, and inadequate aquaculture practices. Despite its commercial importance, large-scale seed production remains underdeveloped owing to critical gaps in species identification, reproductive management, induced breeding, and larval rearing protocols.This dissertation aims to bridge these gaps and establish a scientific basis for the sustainable aquaculture of C. striata in Bangladesh. Four sequential studies were conducted: (i) species identification and phylogenetic analysis using geometric morphometrics and COI gene-based DNA barcoding; (ii) assessment of growth and reproductive biology of wild populations from the Atrai River system; (iii) standardization of hormonal induction protocols using carp pituitary extract (CPE) and Buserelin; and (iv) evaluation of weaning strategies for hatchery-produced larvae using Artemia, fish paste, and formulated feeds. The results confirmed clear species delineation among native and exotic Channa spp., with phylogenetic divergence supported by both morphometric and molecular data. Wild C. striata exhibited seasonal reproduction, with peak spawning from April to July. Induced breeding trials demonstrated that both CPE (80 mg/kg) and Buserelin (0.80 µg/kg) effectively stimulated spawning. Larval weaning experiments revealed that initial live feeding with Artemia followed by gradual transition to formulated diets ensured high survival and growth, while water quality, particularly ammonia concentration, played a critical role. Overall, this research provides a comprehensive framework for the conservation and aquaculture of C. striata by integrating taxonomic validation, reproductive biology, induced breeding, and larval nutrition. The findings are expected to support the development of standardized hatchery protocols, contribute to wild stock conservation, and promote commercial-scale seed production in Bangladesh. Future research should emphasize selective breeding, advanced larval nutrition, and field-level application of the proposed protocols for long-term sustainability.