Oxygen Uptake In Relation To Sex And Different Phases Of Breeding Cycle In Channa Gachua (Ham.)

Abstract

The nutrients release energy during the metabolic process of oxidation. The energy is used, on priority basis, for maintenance of life process; growth and other functions use surplus energy. Respiration and metabolic demands in fishes are profoundly influenced by reproductive physiology, environmental rhythms, and sex-specific behaviors. Channa gachua (Ham.) is a small air-breathing freshwater teleost in the family Channidae. Its respiration involves both aquatic and aerial oxygen uptake due to specialized accessory respiratory organs. The species also undergoes cyclic gonadal changes through discrete reproductive phases resting, preparatory, pre-spawning, spawning, and post-spawning, which modulate its physiological demands.Oxygen uptake and equivalent energy utilization (E.E.U.) in relation to sex and different phases of breeding cycle was studied in the adult air-breathing murrel fish, Channa gachua (Ham.). The values were higher in males (3.221 ml/h) as compared to females (2.715 ml/h). For different breeding phases, the values were minimum in resting phase (1.1473 ml/h) and followed in increasing order by postspawning (3.2708 ml/h), preparatory (3.4963 ml/h), spawning (5.3295 ml/h) and prespawning (5.5905 ml/h) periods. Understanding oxygen uptake in relation to these reproductive stages and sex differences is vital for advancing physiological ecology, aquaculture management, and conservation of this species.