1. Fish parasites cause significant loss in Indian Major Carps specially during winter at West Bengal, India.
  2. Fluctuation of environmental condition, mainly water quality parameters is the main criteria for which fishes are susceptible to diseases.
  3. Methodology to assess the situation are Prevalence study, water quality parameter study and statistical analysis.
  4. Myxozoans show the highest prevalence of infestation and Monogeneans show the lowest.
  5. Labeo rohita is mostly affected by the parasites because of its low immunity power than other carp species.