The effect of subchronic oral exposure to zearalenone on hematologic and biochemical analytes, and the blood redox status of adult rabbit bucks

An overview of mycotoxicoses in rabbits

Mycotoxicoses are usually a consideration in large animal species but can affect companion animals as well. Due to increasing interest and the ease of using rabbits as laboratory models, a growing number of published experimental studies discuss the effects of various mycotoxins on this species. However, the available evidence is fragmented and heterogeneous, and has not recently been collated in a review, to my knowledge. Although mycotoxicoses in rabbits are typically subclinical, clinical signs can include weight loss, anorexia, gastrointestinal disorders, stunted growth, reproductive abnormalities, and susceptibility to infections. An antemortem diagnosis typically relies on a comprehensive clinical history, and assessment of clinical signs and relevant laboratory findings, with confirmation of exposure achieved through the measurement of mycotoxin concentrations in feed or target organs. My review focuses on the clinicopathologic and histopathologic effects of the mycotoxins most important in rabbits, including fumonisins, ochratoxins, aflatoxins, trichothecenes, and zearalenone. This review offers a thorough overview of the effects of mycotoxins in rabbits, serving as a one-stop resource for veterinary practitioners, diagnosticians, and researchers.

Co-Occurrence of Aflatoxin B1, Zearalenone and Ochratoxin A in Feed and Feed Materials in Central Italy from 2018 to 2022

Mycotoxin contamination of feed and feed materials represent a serious health hazard. This study details the occurrence of aflatoxin B1 (AFB1), zearalenone (ZEN) and ochratoxin A (OTA) in 826 feed and 617 feed material samples, collected in two Italian Regions (Umbria and Marche) from 2018 to 2022 analyzed using a UPLC-FLD platform. The developed method was validated and accredited (ISO/IEC 17025) with satisfactory accuracy and precision data obtained in repeatability and intralaboratory reproducibility conditions. Feed had a higher incidence of contaminated samples (26%) with respect to feed materials (6%). AFB1 was found up to 0.1045 mg/kg in cattle feeds and 0.1234 mg/kg in maize; ZEN was detected up to 6.420 mg/kg in sheep feed while OTA was rarely reported and in lower concentrations (up to 0.085 mg/kg). Co-contamination of at least two mycotoxins was reported in 0.8% of the analyzed samples. The incidence of above maximum content/guidance level samples was 2% for feed and feed materials while almost 3-fold-higher for maize (5.8%) suggesting how mycotoxin contamination can affect some matrices more than others. Obtained data can be useful to improve official monitoring plans and therefore further raise awareness of this issue between agriculture stakeholders, healthcare entities and non-professionals.

Quercetagetin alleviates zearalenone-induced liver injury in rabbits through Keap1/Nrf2/ARE signaling pathway

Introduction: This study aimed to assess the alleviative effect of quercetagetin (QG) on zearalenone (ZEN)-induced liver injury in rabbits. Methods: Ninety 41-day-old healthy Hyla rabbits were randomly assigned into three groups, including a control (fed with basic diet), ZEN addition group (fed with basic diet + 600 μg/kg ZEN), and ZEN + QG addition group (fed with basic diet + 600 μg/kg ZEN + 100 mg/kg QG), with 30 rabbits per group. The duration of the experiment was 28 days. Results: The results revealed no significant differences in the average daily gain, average daily feed intake, the gain to feed ratio and the liver, kidney and spleen organ indexes (p > 0.05) between the rabbits across the three groups. However, the sacculus rotundus index of the rabbits in the control group was significantly higher than that in the ZEN + QG group (p < 0.05). The intake of ZEN-contaminated diet also significantly increased the activities or levels of alanine transaminase, alkaline phosphatase, total bile acid (TBA), total bilirubin, malondialdehyde, and interleukin-4 (IL-4) and enhanced the abundance of kelch-like ECH-associated protein 1 (Keap1), heat shock protein 70 (HSP70) and cysteine-aspartic acid protease-3 (Caspase-3) mRNA in the blood or liver tissue in ZEN group, compared to the control group (p < 0.05). On the contrary, the activities or levels of immunoglobulin A, complement 3, total antioxidant capacity, glutathione peroxidase (GSH-Px), superoxide dismutase, interleukin-10, and the abundance of nuclear factor E2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) mRNA were significantly decreased (p < 0.05). Supplementing the diet with QG still maintained significantly higher levels of TBA and IL-4, and the abundance of GSH-Px, HSP70, IL-4, and Caspase-3 mRNA in the blood and liver of rabbits in the ZEN + QG group than in the control group (p < 0.05). At the same time, the other indicators were restored to levels in the control group (p > 0.05). Discussion: In conclusion, QG alleviated the ZEN-induced oxidative damage and liver injury caused by inflammatory reaction through the Keap1-Nrf2-antioxidant response element (ARE) signal pathway, which protected the liver. This study revealed the alleviative effect of QG on the hepatotoxicity of ZEN in rabbits for the first time, providing a new perspective for applying QG and developing a ZEN antidote.