Abdel-Tawwab et al. 2023 — Cadmium residues in gilthead seabream muscle, liver, and gills; yeast dietary mitigation
This controlled feeding trial measured Cd bioaccumulation in gill, liver, and muscle tissues of gilthead seabream (Sparus aurata) exposed to waterborne Cd (0, 1.0, and 2.0 mg Cd/L) and fed diets supplemented with Saccharomyces cerevisiae (0%, 0.5%, 1.0%) for 60 days. Cd concentrations in gill, liver, and muscle all increased dose-dependently with Cd exposure; liver retained the highest Cd residue, followed by gills, with muscle showing the lowest accumulation. Dietary yeast supplementation (1.0%) lowered Cd residues in fish organs and ameliorated the adverse effects of Cd toxicity on growth, haematology, and histopathology. The study reports quantitative Cd residues in muscle tissue of a commercially important marine food fish species under controlled contamination conditions.
Key numbers
- Cd exposure levels: 0, 1.0, and 2.0 mg Cd/L waterborne
- Cd tissue distribution: liver > gills > muscle across all Cd-exposed groups
- Cd in muscle increased significantly with Cd exposure, especially at 2.0 mg Cd/L; specific values in Table format in source
- Dietary yeast 1.0% significantly reduced Cd residues in all tissues vs. yeast-free Cd-exposed fish
- No significant Cd changes in yeast-fed fish without Cd exposure (confirming dietary yeast alone does not elevate tissue Cd)
- Growth parameters, haematological parameters, cortisol, glucose, cholesterol, triglycerides, LDH, ALT, AST, ALP, and DNA fragmentation all impaired by Cd and improved by dietary yeast
- Mediterranean marine aquaculture species; annual world production ~160,000 tonnes
- Journal: Ecotoxicology
Methods (brief)
Controlled aquarium trial; 3×3 factorial design; 60 days; ICP-MS or AAS for tissue Cd analysis; tissues: gill, liver, muscle. Egypt (Central Laboratory for Aquaculture Research). Certified reference materials used for QC.
Implications
Certification: Demonstrates dose-dependent Cd accumulation in muscle of a commercially farmed marine fish; muscle Cd is lowest among analyzed tissues but present even at 1.0 mg Cd/L exposure. Dietary yeast as a mitigation strategy in aquaculture settings. Courses: Strong case study for bioaccumulation of Cd in aquaculture fish under controlled conditions; tissue distribution hierarchy (liver > gills > muscle) illustrates organ-specific accumulation. App: Seabream and marine aquaculture fish should carry Cd contamination flags where water quality is uncertain; tissue-specific data supports muscle-focused app estimates. Microbiome: Not applicable.