Ecology

Biology

Fish <Actinopterygii>

Fishery

Biochemistry

Immunology

Immune system

Microplastics

Oxidative stress

Antioxidant

Juvenile

Zoology

Snakehead

Aquaculture Reports

Microplastics pollution has gained much attention for its harmful impact on aquatic organisms. This study aimed to evaluate the size-effects and concentration-effects of microplastics on the physiology of hybrid snakehead (Channa maculate × Channa argus). Parameters including antioxidant enzyme activities, intestinal morphology, immune-related genes, and oxidative-stress-related genes were tested in two life stages development. The results showed hybrid snakehead larvae (0.057 ± 0.009 g in weight) were more intolerant to high concentrations of small-sized microplastics. Hybrid snakehead juvenile (3.87 ± 1.19 g in weight) had been stimulated the immune response and triggered antioxidant defenses under the exposure stress. There were differential expressions of inflammatory and oxidative-stress-related genes coping with differential sizes and concentrations of microplastics. High concentrations of microplastics (2 mg/L, 20 mg/L) stimulated more severe immune response and shortened intestinal villi. In addition, the damaged intestinal morphology and function did not recover after 48 h of depuration. This work is expected to provide a meaningful perspective for better understanding the size and concentration dependent effects and life-stage specific effects of microplastics in hybrid snakehead.

Size and concentration effects of microplastics on digestion and immunity of hybrid snakehead in developmental stages