Maturation and Spawning Biology of a Hill Stream Major Carp Labeo dyocheilus (McClelland 1839) from Central Himalaya, India

Abstract

Fishes adapt to reproduce under most variable environmental conditions. Teleost gonadal structure, function and reproductive processes are controlled by biological rhythms as well as various environmental factors. Study area was W. Ramganga, Chaukhutia (Latitude: 29°53'55"N and Longitude: 79°21'22"E), for a period of three years. GSI, an indicator of sexual maturity, reported in our experiment varied from 0.008 in October to 3.933 in July for male fish and from 0.099 in October to 10.508 in July for female. Thus, onset of rainfall (Aug-Sep) was considered as the breeding season. We also found out that the maturity of ovaries and testis exist in seven stages, namely Immature or Virgin, Maturing Virgin, Developing, Maturing, Ripening, Spawning or Running, and Spent. The spawning sites were found to be in the small patches of slow running water. Specific ranges of Physico-chemical parameter were found to be responsible for spawning in this study. The experimental fish was observed to show sexual dimorphism during breeding season. During this period, the male fish became slightly brighter in color while the female fish became darken in color. This study would helpful for productive aquaculture, scientific based fishery management, and commercial utilization.