Asian Journal of Fisheries and Aquatic Research

Impact of Helminth Infection on Physiological, Hematological, Biochemical, and Immune Parameters of Ornamental Fishes from Latur District, Maharashtra, India

Shivkant Madhukar Gutte, Datta Ashok Nalle — Sat, 11 Jul 2026 00:00:00 +0000

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.

Feeding Habits, Length-weight Relationship and Condition Factor of Spotted Tilapia (Tilapia mariae; Boulenger, 1899) (Pisces: Cichlidae) in the Adofi River, Niger Delta, Nigeria

Mon, 13 Jul 2026 00:00:00 +0000

The food and feeding habits of fish have long attracted considerable attention from researchers, as they constitute a fundamental basis for the development and implementation of effective fisheries management programmes in both capture and culture fisheries. A comprehensive understanding of feeding ecology provides valuable insights into trophic interactions, resource utilisation, growth performance and habitat requirements, thereby facilitating the sustainable exploitation, conservation and management of fish populations. Cichlids are a dominant fish family in the Adofi River, and Tilapia mariae forms a significant component of local diets. The present study aimed to provide information on the food, feeding habits and growth characteristics of T. mariae from a stretch of the Adofi River, Niger Delta, Nigeria. The natural food of the species was studied from the stomach contents of 250 fish samples measuring 5.1-17.5 cm standard length and weighing 18.7-229.4 g. Stomach contents were analysed using the frequency of occurrence, numerical, fullness and point methods. Green algae, diatoms and desmids were the main food items of plant origin. Filamentous algae were the most preferred food items of plant origin, occurring in more than 90.0% of the fish examined. Coleoptera, diptera, trichoptera and chironomid larvae were the food items of animal origin. Feeding intensity varied seasonally, with peaks during the wet season. Tilapia mariae in the Adofi River was a daytime feeder, as the number of stomachs containing food items was significantly higher (P < 0.05) during the day (176) than at night (11). The fish showed a negative allometric growth pattern (b < 3). Monthly condition factor ranged from 2.0 to 3.2 and varied with individual fish length. Condition factor was higher during the wet season months. The baseline ecological data obtained for the first time on this species in the river, a first-order tropical stream in the Niger Delta, will provide information for future fish growth and food analyses, as well as for fisheries exploitation, management and conservation.

Assessment of the Genotoxic Potential of Mancozeb and Propiconazole Fungicides in the Freshwater Catfish Clarias batrachus: A Study Protocol

Tanya, Neeru Singh — Sat, 11 Jul 2026 00:00:00 +0000

Background: Mancozeb and propiconazole are widely used agricultural fungicides that can enter freshwater bodies through surface runoff and may affect non-target aquatic organisms. Clarias batrachus, a freshwater catfish of ecological and food-fish significance, is frequently associated with habitats exposed to agricultural effluents and provides a suitable model for cytogenetic assessment because of its nucleated erythrocytes. This study protocol outlines an approach for assessing the genotoxic potential of mancozeb and propiconazole, individually and in combination, in C. batrachus. The proposed design includes acute and chronic exposure scenarios, sub-lethal concentrations derived from LC₅₀ values, and biomarker-based evaluation of DNA damage in blood, gill, liver and kidney tissues. The principal endpoints include the alkaline comet assay, micronucleus test and chromosomal aberration analysis, supported by oxidative stress markers such as SOD, CAT, GPx and MDA. Molecular analysis of DNA repair and stress-response genes is also proposed to clarify possible mechanisms of toxicity. The protocol further emphasises environmentally relevant exposure conditions, mixture-toxicity assessment and standardised sampling procedures. The expected outcome is a structured framework for generating species-specific evidence on fungicide-induced genotoxicity in C. batrachus. Such data may support aquatic biomonitoring, ecological risk assessment and future management of pesticide contamination in freshwater environments.

Observations on the Types of Deformed Larvae Encountered during Induced Spawning of a Threatened Catfish, Ompok bimaculatus (Bloch,1794)

S. K. Sahoo, A. K. Chaudhari, S. N. Sahoo, S. S. Giri — Fri, 10 Jul 2026 00:00:00 +0000

Larval deformity is a recurring hatchery concern because it reduces seed quality, production efficiency, growth and survival. The present study recorded and categorised the visible morphological anomalies encountered during induced spawning and hatching of the threatened butter catfish, Ompok bimaculatus. Broodfish weighing 90–120 g were collected during July, and females were induced with Ovatide at 1 mL/kg body weight. Eggs obtained after stripping were fertilised with sperm suspension prepared from harvested testes and incubated in a flow-through plastic-tub hatchery. Approximately 300–400 fertilised eggs were placed in each hatching tub, and hatching was allowed for 24–26 h. Deformed larvae were collected from four breeding attempts, segregated initially using a magnifying glass and confirmed under a stereozoom microscope. The observed deformities were classified as teratoma, acephala, dwarf larvae and axial deformity. Teratoma was characterised by an undifferentiated embryonic mass without distinct body parts; acephala showed an indistinct head region; dwarf larvae were smaller than normal hatchlings; and axial deformity involved bending or multiple curvatures of the trunk and/or tail. Normal larvae were 4–5 mm long, whereas some deformed larvae were 2–3 mm or 2.6–3.1 mm long. Deformity was generally 5–7% during usual breeding operations and increased to 10–15% during late breeding. The observations indicate that visible larval deformities are important practical indicators of hatchery seed quality in O. bimaculatus.