Asian Journal of Fisheries and Aquatic Research

Helminth infections are among the major health challenges affecting ornamental fish culture, leading to physiological stress, metabolic disturbances, and impaired immune function. This study evaluated the association between naturally occurring helminth infections and physiological, haematological, biochemical, immunological, and parasitological parameters in ornamental fishes collected from aquarium fish shops and culture units in Latur District, Maharashtra, India. A total of 120 ornamental fishes representing ten commercially important species were examined and categorised into healthy (n = 45) and helminth-infected (n = 75) groups following parasitological screening. Comparative analyses were performed using an independent Student's t-test at a significance level of p < 0.05. Helminth-infected fishes exhibited significantly lower body weight, condition factor, hepatosomatic index, gonadosomatic index, haemoglobin concentration, erythrocyte count, serum protein, cholesterol, triglycerides, lysozyme activity, and total immunoglobulin levels than healthy fishes. Conversely, leukocyte count, serum glucose concentration, liver enzyme activities (AST, ALT, and ALP), and respiratory burst activity were significantly higher in infected fishes, indicating physiological stress and altered innate immune responses. The overall prevalence of helminth infection was 62.5%, with the highest prevalence observed in koi carp and Oscar fish. These findings demonstrate a significant association between helminth infection and deterioration of physiological condition, haematological profile, metabolic status, and immune function in ornamental fishes. The study highlights the importance of routine health monitoring, effective parasite management, and improved biosecurity practices for sustainable ornamental aquaculture.