Search

Abstract Microplastics (MPs) form when plastic debris is released into the aquatic environment, where they decompose and have deleterious effects on aquatic life. This study aimed to examine the harmful impacts of polystyrene MPs (PS-MPs) on the growth, carcass composition, hematology, digestibility, histopathology, and mineral analysis of Catla catla (11.09 ± 0.09 g/fish). Six experimental diets were prepared using canola meal (CM) as the base, each containing varying levels of PS-MPs: a control diet without MPs, and diets with 0.5%, 1%, 1.5%, 2%, and 2.5% PS-MPs. For ninety days, three groups of 15 fingerlings each were fed the test diets at a rate of 5% of their live, wet body weight. The growth rate and feed intake of C. catla fish showed a significant decline after the exposure to the diet containing 2.5% PS-MPs. Dietary inclusion of 2.5% PS-MPs resulted in reduced weight gain (g) and increased FCR. Mineral content and nutritional digestibility declined as PS-MP levels rose. PS-MPs led to a decrease in ash and protein content, while causing an increase in moisture levels and body fat. Moreover, exposure to PS-MPs resulted in significant reduction in RBCs, PLT, Hb, PCV, and MCHC, while WBCs, MCH, and MCV showed substantial increases. The histological analysis of the gut revealed elevated intestinal irregularities at 2.5% PS-MPs level. Notably, the present study revealed that PS-MPs accumulate in the gut, compromising the nutritional quality and overall well-being of C. catla fingerlings.

The widespread presence of microplastics (MPs) in aquatic ecosystems raises concerns about their potential harm to aquatic life, particularly fish, which are a vital source of protein for human consumption. It emphasizes the importance of examining their occurrence and impacts. The focus of this study was to find out deleterious effects of polylactic acid MPs (PLA-MPs) on the Catla catla fingerlings by observing their growth, body composition, digestibility, histopathology, blood health, and mineral analysis. Utilizing sunflower meal (SFM) as the basal diet, six test diets were formulated, incorporating distinct MP concentrations: control (no MPs), 0.5 %, 1 %, 1.5 %, 2 %, and 2.5 %. These test diets were tested in three replicates of 15 fingerlings per tank and fed at 5 % equivalent of their live wet body weight for 90 days. After exposure to 2.5 % MPs, C. catla, fingerlings showed a significant decline in growth rate and feed utilization. Increased FCR and decreased WG (g) were observed in 2.5 % PLA-MPs. As MP levels increased, nutrient digestibility and minerals content decreased. PLA-MPs increased body fat and moisture, but decreased protein and ash content. MP exposure leads to significant changes in hematological parameters, including decreased RBCs, Hb, PLT, PCV, and MCHC, and increased WBCs, MCH, and MCV. Furthermore, histopathological examination of the gut showed increased intestinal abnormalities at the 2.5 % PLA-MPs concentration. This study underscored the adverse effects of PLA-MP pollution on the overall health performance of C. catla fingerlings.

Recently, aquaculture species have been facing various negative consequences of ingesting microplastics (MPs). In order to find out the adverse impacts of MPs, this study aimed to assess growth, body composition, nutrient digestibility, hematological indices and gut histopathology of Catla catla fingerlings by the dietary exposure of polystyrene MPs (PS-MPs). C. catla (initial weight, 7.03±0.02 g; n, 270) were given PS-MPs at different inclusion concentrations i.e., 0 %, 0.5 %, 1 %, 1.5 %, 2 % and 2.5 % for 90 days. Fish were fed twice a day, about 5 % of their live weight. The water quality parameters such as temperature (25–27 °C), pH (7.3–8.3), dissolved oxygen (5.4–7.2 mg/L) were maintained at the regular basis throughout the experiment. PS-MPs significantly (p