Exploring the combined interplays: Effects of cypermethrin and microplastic exposure on the survival and antioxidant physiology of Astacus leptodactylus.

Plastic waste and micro/nanoplastic particles pose a significant global environmental challenge, along with concerns surrounding certain pesticides' impact on aquatic organisms. This study investigated the effects of microplastic particles (MPPs) and cypermethrin (CYP) on crayfish, focusing on biochemical indices, lipid peroxidation, oxidative stress, hematological changes, and histopathological damage. After determining the LC50-96 h value (4.162 µg/L), crayfish were exposed to sub-lethal concentrations of CYP (1.00 ppb (20%) and 2.00 ppb (50%)) and fed a diet containing 100 mg/kg MPPs for 60 days. Hemolymph transfusion and histopathological examinations of the hepatopancreas were conducted. The results showed significant alterations in crayfish. Total protein levels decreased, indicating protein breakdown to counteract contaminants, while total cholesterol and triglyceride levels declined, suggesting impaired metabolism. Glucose levels increased in response to chemical stress. The decline in total antioxidant capacity highlighted the impact of prolonged xenobiotic exposure and oxidative stress, while increased CAT, SOD, and MDA activities helped mitigate oxidative stress and maintain cellular homeostasis. The elevated total hemocyte count, particularly in semi-granular cells, suggests their active involvement in the detoxification process. Further research is needed to fully understand the implications of these effects.

Effects of Probiotic Bacteria Bacillus on Growth Performance, Digestive Enzyme Activity, and Hematological Parameters of Asian Sea Bass, Lates calcarifer (Bloch).

This study was conducted to evaluate different doses of two species of Bacillus (Bacillus licheniformis and Bacillus subtilis), on growth parameters, chemical composition of fish, activity of liver, and digestive enzymes of Asian sea bass. During 8 weeks, juvenile Asian sea bass received diets supplemented with 1 × 103, 1 × 106, and 1 × 109 CFU g-1 probiotic in addition to a control diet without added microorganisms. At the end of the trial, growth indices (total weight, total length, specific growth rate, total weight gain, food conversion ratio, and condition factor), body composition (crude protein, crude lipid, ash, and dry matter), digestive enzymes (protease, lipase, and amylase), liver enzymes [aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP)], immunologic indicators (lysozyme), and hematological parameters [hematocrit (Hct), hemoglobin (Hb), red blood cells (RBCs), white blood cells (WBCs)] were assessed. Asian sea bass receiving diets supplemented with probiotic Bacillus (Bacillus licheniformis and Bacillus subtilis) showed significantly better growth than those fed the basal diet (control). Regarding body composition, total protein levels and dry matter were higher and lipid levels were lower in fish fed the diet containing 1 × 106 CFU g-1 probiotic compared with the control group (P < 0.05). Digestive enzymes (protease, lipase, and amylase) and hematological parameters (RBC, WBC, and Hb) were all highest in fish fed diet supplemented with 1 × 106 CFU g-1 probiotic Bacillus. Also, liver enzymes (AST, ALT, ALP) were lower in fish fed diet supplemented with 1 × 106 CFU g-1 probiotic Bacillus. Being that supplementation of 1 × 106 CFU g-1 of Bacillus in the diet is the dose which delivers the best results.