Journal of Fisheries

Effects of fish waste silage and vitamin-C supplemented diet on growth and haematological parameters of common carp, Cyprinus carpio (Linnaeus, 1758) fingerlings

2026-04-04T07:41:42+00:00

A 60-day experiment was conducted to evaluate the growth performance, feed utilization and haematological parameters of common carp, Cyprinus carpio under four dietary treatments with three replicates for each. These were control (0%), T1 (15%), T2 (30%) and T3 (45%) fish waste silage containing diets. Nutritional profile of experimental feeds was: crude protein (25–25.75%), lipid (8.46–8.96%), moisture (10.64–11.16%), ash (14.05–14.87%), crude fiber (4.07–4.32%), and nitrogen-free extract (35.69–37%). The haematological parameters were observed of C. carpio, which improving White blood cells, Red blood cells, haemoglobin (Hb) and Hematocrit (HCT) within the healthy physiological range. Growth performance parameters were observed at the end of the experiment. The highest length gain (5.96±0.05 cm), weight gain (8.43±0.15 g), percentage weight gain (161.44±10.14%), specific growth rate (0.46±0.01%), protein efficiency ratio (3.03±0.18 g), hepatosomatic index (0.05±0.00%), and intestinal somatic index (0.33±0.00%) was observed compared to the control groups. The highest feed conversion ratio (1.91±0.47) was observed in control group compared to the treatment group. Carcass composition of the fish at the end of the trial was similarly analyzed for protein (58.87–60.29%), lipid (13.10–13.78%), moisture (10.25–10.96%), ash (9.21–9.32%), and NFE (6.45–0.73%) content. Water quality parameters remained within acceptable limits throughout the study period. The results suggest that specific dietary treatments significantly enhanced growth, haematological parameters, carcass composition, and feed utilization in common carp.

Biosafety and cellular cytocompatibility assessment of endotoxin-reduced Flavobacterium psychrophilum bacteriophages

2026-04-04T07:41:55+00:00

Flavobacterium psychrophilum causes bacterial cold-water disease in salmonids, leading to substantial losses in juvenile rainbow trout aquaculture. Although bacteriophages represent promising antibiotic alternatives, biosafety concerns persist due to endotoxin contamination originating from Gram-negative hosts. In this study, five lytic phages (FpV30–FpV34) were isolated from trout hatchery effluent using F. psychrophilum ATCC 49418 and characterized by one-step growth, adsorption assays, host range analysis, and transmission electron microscopy (TEM). Phages exhibited adsorption constants between 1.21×10⁻⁹ and 1.58×10⁻⁶ mL·min⁻¹, latent periods of 3–6.5 h, and burst sizes of 11–34.5 particles per cell. Spot tests demonstrated high specificity toward F. psychrophilum, with negligible activity against non-target bacteria. TEM revealed icosahedral capsids (≈75–83 nm) and long tails (≈129–142 nm), consistent with Myoviridae-like morphology. Crude lysates were purified by PEG/NaCl precipitation followed by dialysis, resulting in a ~40-fold increase in phage titer (from 1×10⁸ to 4×10⁹ PFU mL^–1) and a 99.8% reduction in endotoxin levels (from 1.2×10³ to 2.3 EU mL^–1), confirmed by chromogenic LAL assay with interference control. Cellular cytocompatibility assessed in MCF-7 cells revealed that crude preparations reduced viability to 58% at 48 h, whereas endotoxin-reduced phages maintained >90% viability. These findings demonstrate that PEG/NaCl-based purification enables high-titer, low-endotoxin F. psychrophilum phage preparations with favorable cytocompatibility, supporting their biosafe application in aquaculture.

Influence of dietary garlic powder (Allium sativum) on growth performance, hemato-biochemical parameters, antioxidant status, and hepatic enzyme activity in Catla catla fingerlings

2026-04-04T07:42:08+00:00

This study evaluated the impact of dietary garlic powder (Allium sativum) on growth performance, hematology, lipid profile, hepatic enzyme activity, and antioxidant activity in Catla catla fingerlings over a 90-day feeding trial. A total of 120 fish (initial weight: 5.86±0.14 g) were divided into four dietary groups: 0% (Group-1), 2% (Group-2), 4% (Group-3), and 6% (Group-4) garlic powder. Results indicated that final weight (41.17±7.04 g), weight gain (35.5±7.11 g), feed intake (52.2±0.96 g), and specific growth rate (3.59±0.08%) were higher in Group 4 (p < 0.001). Feed conversion ratio improved significantly (1.22±0.015; p < 0.001). Hematological values, including red blood cell counts (2.63±0.014 ×10⁶ mm^–3), hemoglobin (13.58 ± 0.106 g 100 mL^–1), and packed cell volume (40.9±0.5%) increased significantly (p < 0.001) in Group-4. In contrast, white blood cell counts (WBCs) were significantly reduced (p = 0.008). Biochemical parameters such as triglycerides (102.3±4.72 mg dL^–1), cholesterol (134.2±2.26 mg dL^–1), low-density lipoprotein (45.56±2.19 mg dL^–1), and very low-density lipoprotein (20.24±0.94 mg dL^–1) decreased significantly, while high-density lipoprotein improved. Hepatic enzymes AST (53.8±0.37 U L^–1), ALT (18.2±1.14 U L^–1), ALP (172.6±0.4 U L^–1), and LDH (170±1.04 U L^–1) were reduced (p < 0.001). Antioxidant enzymes catalase (26.2±0.23 KU L^–1), superoxide dismutase (16±0.31 U mL^–1), and glutathione peroxidase (65.8±0.58 U L^–1) increased (p < 0.001), while MDA levels were lowered (2.38±0.058 mmol L^–1), indicating reduced oxidative stress. In conclusion, garlic powder supplementation, particularly at 6%, significantly enhanced growth, hematological status, lipid regulation, liver function, and antioxidant defense in C. catla, supporting its potential use as a natural feed additive in freshwater aquaculture.

Fish as medicine: indigenous traditional knowledge and practices in Northeast India

2026-04-04T07:42:20+00:00

Northeast India, often referred to as the bio-geographical gateway of the country. It is home to rich biodiversity and diverse indigenous communities with deep-rooted traditional knowledge systems. Among these, ichthyofauna plays a pivotal role in ethnomedicinal practices, reflecting the intricate relationship between humans and their environment. This study aims to document and analyse the therapeutic applications of fish species traditionally used for healthcare in Northeast India. Through the PRISMA method, we identified and selected 21 articles reporting the use of fish as ethnomedicine in Northeast India. A total of 70 fish species from 27 families were identified, including Channa punctata and Monopterus cuchia, which are commonly used for respiratory and gastrointestinal ailments. Findings reveal that fish-based remedies are deeply integrated into the cultural and spiritual beliefs of local communities, emphasizing a holistic approach to health. This study highlights the potential of integrating traditional ichthyotherapeutic knowledge with modern medicine to create sustainable and culturally appropriate healthcare solutions. Furthermore, it underscores the importance of preserving this indigenous knowledge for future generations while ensuring ecological sustainability.

Effects of dietary supplementation of peppermint (Mentha piperita) on growth, survival and haemato-biochemical profile of common carp (Cyprinus carpio) fingerlings

2026-04-04T07:42:32+00:00

Herbal feed additives are increasingly explored in aquaculture as natural alternatives to synthetic growth promoters and immunostimulants. Peppermint (Mentha piperita), known for its bioactive phytochemicals and antioxidant properties, has shown potential benefits for fish health and metabolism. A 60-day feeding trial was conducted using 120 fingerlings (initial mean weight: 10.2±0.02 g; length: 9.63±0.03 cm) randomly distributed into four experimental groups, each with three replicates, following a completely randomized design. Experimental diets were prepared by incorporating peppermint leaf powder at 0% (control), 1%, 2%, and 3% per kg of feed weight (designated as T1, T2, and T3, respectively). After 60 days, fish fed the diet containing 3% peppermint (T3) exhibited significantly higher (p < 0.05) weight gain, protein efficiency ratio, average daily growth, and specific growth rate compared to other treatments. A significant increase (p < 0.05) in white blood cell (WBC) count was also recorded in the T3 group, indicating enhanced immune response. No significant differences were observed in red blood cell count, haemoglobin, packed cell volume, platelets, lymphocytes, monocytes, mean corpuscular hemoglobin concentration, mean corpuscular hemoglobin, or mean corpuscular volume among treatments. No mortality was observed in any group throughout the experimental period. Overall, dietary supplementation with 3% peppermint leaf powder improved growth performance, stimulated immune function, and maintained normal hematobiochemical parameters in common carp, supporting its potential as a safe and effective natural additive in sustainable aquaculture.