Aflatoxin B1 (AFB1) is a potent
carcinogen that causes growth
stunting, immunosuppression and
liver cancer in multiple species. The recent trend of replacing fishmeal with plant-based
proteins in fish feed has amplified the AFB1 exposure risk in farm-raised fish. NovaSil (NS), a
calcium montmorillonite clay, has previously been shown to reduce AFB1 bioavailability safely and efficaciously in several mammalian species. This study was designed to: (1) evaluate AFB1 impact on cultured red drum, Sciaenops ocellatus, over the course of seven weeks; and (2) assess NS supplementation as a strategy to prevent
aflatoxicosis. Fish were fed diets containing 0, 0.1, 0.25, 0.5, 1, 2, 3, or 5 ppm AFB1. Two additional treatment groups were fed either 5 ppm AFB1 + 1% NS or 5 ppm AFB1 + 2% NS.
Aflatoxin B1 negatively impacted red drum
weight gain, survival, feed efficiency, serum
lysozyme concentration, hepatosomatic index (HSI), whole-body
lipid levels, liver histopathological scoring, as well as
trypsin inhibition. NovaSil inclusion in AFB1-contaminated diets improved
weight gain, feed efficiency, serum
lysozyme concentration, muscle somatic index, and intraperitoneal fat ratios compared to AFB1-treated fish. Although not significant, NS reduced AFB1-induced histopathological changes in the liver and decreased
Proliferating Cell Nuclear Antigen (
PCNA) staining. Importantly, NS supplementation improved overall health of AFB1-exposed red drum.