Published Paper Details:

The present study investigated the ecological dynamics of trematode parasitism in freshwater fish Channa spp. From the river Rapti, Uttar Pradesh, India, during January-December 2025. Monthly and seasonal sampling was conducted to assess variations in infection parameters in relation to environmental and water quality factors. Fish hosts were analyzed for trematode parasites, and ecological indices for instance, prevalence, average intensity, relative density, abundance, dominant percentage, and infestation index calculation were performed. The results revealed pronounced monthly and seasonal reflection in trematode infection, with peak prevalence and parasite load recorded during late summer and early monsoon months, while the lowest values were noted during winter. Seasonal analysis indicated highest infection spring and summer, suggesting favorable environmental conditions for the transmission of parasites during warmer periods. Physico-chemical and microbiological parameters of water showed noticeable variation across months, which appeared to influence parasite prevalence and host susceptibility. Pearson correlation analysis demonstrated strongly significant positive correlation between the number of infected hosts and major infection indices. Overall, the findings highlighted the strong influence of seasonal and environmental factors on trematode parasitism in Channa spp., emphasizing the ecological sensitivity of host-parasite interactions in freshwater ecosystems.