Seasonal and Age-related Variations in Physiological Indices of Cyprinus carpio haematopterus (Amur Common Carp) in Temperate Aquaculture

Abstract

The physiological condition of cultured fish serves as a crucial indicator of health status, reproductive maturity, and environmental adaptation. This study investigated seasonal and age-related variations in physiological indices of Cyprinus carpio haematopterus (Amur common carp) at temperate region of Pantnagar, Uttarakhand. Female specimens of three age groups (0+, 1+, 2+ years) were sampled across four seasons (July, October, January, March), and four physiological indices viz. Condition Factor (CF), Specific Condition Factor (SCF), Hepatosomatic Index (HSI), and Gonadosomatic Index (GSI) were measured. CF values ranged from 1.46±0.03 to 1.94±0.07, with highest values in spring. SCF showed remarkable stability (1.27±0.02 to 1.58±0.06), indicating consistent somatic condition independent of reproductive investment. HSI fluctuated notably (0.82±0.13 to 1.69±0.11), with autumnal elevation reflecting pre-winter energy storage. GSI exhibited pronounced seasonal variation (3.18±0.24 to 18.53±0.66), with spring peaks indicating spawning season onset. Age-dependent analysis revealed 2+ fish demonstrated higher condition indices, suggesting cumulative effects of growth and maturation. These findings provide empirical foundations for season- and age-specific aquaculture management protocols and breeding program optimization for temperate carp culture.