Different mycotoxins in feed lead to combined exposure, increasing adverse effects on animal health. Trichothecene mycotoxins have been associated with inducing oxidative stress, which is neutralized by the glutathione system within the antioxidant defense, depending on the dose and duration of exposure. T-2 toxin, deoxynivalenol (DON), and fumonisin B1 (FB1) are commonly found in feed commodities simultaneously. In the present study, the intracellular biochemical and gene expression changes were investigated in the case of multi-mycotoxin exposure, focusing on certain elements of the glutathione redox system. In a short-term feeding trial, an in vivo study was performed with low (EU-proposed) doses: T-2/HT-2 toxin: 0.25 mg; DON/2-AcDON/15-AcDON.: 5 mg; FB1: 20 mg/kg feed, and high doses (twice the low dose) in laying hens. The multi-mycotoxin exposure affected the glutathione system; GSH concentration and GPx activity was higher in the liver in the low-dose group on day 1 compared to the control. Furthermore, the gene expression of antioxidant enzymes increased significantly on day 1 in both exposure levels compared to the control. The results suggest that when EU-limiting doses are applied, individual mycotoxins may have a synergistic effect in the induction of oxidative stress.

In the context of nephrotoxic risks associated with environmental contaminants, this study focused on the impact of mycotoxin exposure on the renal health of laying hens, with particular attention to oxidative stress pathways. Sixty laying hens were assigned to three groups—a control group (CON), a low-dose mycotoxin group (LOW), and a high-dose mycotoxin group (HIGH)—and monitored for 72 h. Mycotoxin contamination involved T-2/HT-2 toxin, DON/3-AcDON/15-AcDON, and FB1 at their EU-recommended levels (low mix) and at double doses (high mix). Clinical assessments revealed no signs of toxicity or notable weight changes. Analysis of the glutathione redox system parameters demonstrated that the reduced glutathione content was lower than that in the controls at 48 h and higher at 72 h. Glutathione peroxidase activity increased in response to mycotoxin exposure. In addition, the gene expression patterns of key redox-sensitive pathways, including Keap1-Nrf2-ARE and the AhR pathway, were examined. Notably, gene expression profiles revealed dynamic responses to mycotoxin exposure over time, underscoring the intricate interplay of redox-related mechanisms in the kidney. This study sheds light on the early effects of mycotoxin mixtures on laying hens’ kidneys and their potential for oxidative stress.

The effects of combined short-term (3 days) exposure to Fusarium mycotoxins at both the EU recommended limit (T-2/HT-2 toxin: 0.25 mg/kg; DON/3-AcDON/15-AcDON: 5 mg/kg; FB₁: 20 mg/kg) and twice the dose (T-2/HT-2 toxin: 0.5 mg/kg, DON/3-AcDON/15-AcDON: 10 mg/kg, and FB₁: 40 mg/kg feed) on the kidneys of laying hens were examined. Our study aimed to investigate how these mycotoxins interacted with membrane lipid fatty acid (FA) composition and lipid peroxidation processes. It was observed that the levels of conjugated dienes and trienes were higher than the control in the low-mix group on day 3, and malondialdehyde concentration was higher on days 2 and 3. The proportion of phospholipid (PL) FAs showed that saturated and monounsaturated FAs increased. Still, both n3 and n6 polyunsaturated FAs decreased significantly on day 2 of exposure in the high-mix group. Among the n3 FAs, the level of docosahexaenoic (C22:6 n3) and among n6 FAs, arachidonic (C20:4 n6) acids decreased mainly on day 2 in the high-mix group. The results suggest that the combined exposure to Fusarium mycotoxins induced lipid peroxidation in the kidneys of laying hens, which resulted in marked changes in the PL FA profile. Histological examination revealed time- and dose-dependent increases as consequences of mycotoxin exposure.

This study examined the effects of ochratoxin A (OTA) exposure and graded dietary selenium (Se) supplementation on fatty acid (FA) composition and oxidative stress markers in the liver of broiler chickens. OTA is known to generate oxidative stress, promote lipid peroxidation, and affect the antioxidant system. Se, an essential trace element with antioxidant properties, may help counteract OTA-induced toxicity. In this short-term (5-day) in vivo feeding experiment, 21-day-old broiler chickens were divided into six groups, each with six birds: Control (diet free from Se), 0.3 mg/kg Se, 0.5 mg/kg Se, 2 mg/kg OTA, 2 mg/kg OTA + 0.3 mg/kg Se, 2 mg/kg OTA + 0.5 mg/kg Se. Our findings show that supplementing 0.3 mg/kg (p < 0.01) or 0.5 mg/kg Se (p < 0.001) in OTA-exposed birds significantly reduced the early oxidative stress markers (conjugated dienes and trienes) and significantly increased (0.3 mg/kg p < 0.01; 0.5 mg/kg p < 0.001) glutathione levels, indicating enhanced glutathione-dependent antioxidant protection. The treatments also significantly altered the ratio of monounsaturated and n6/n3 polyunsaturated FAs. OTA with 0.3 mg/kg Se supplementation significantly (p ˂ 0.05) reduced total unsaturation and FA average chain length. At a dose of 0.3 mg/kg, the interaction of Se and OTA altered the PUFA composition, while 0.5 mg/kg Se supplementation enhanced antioxidant defense and reduced lipid peroxidation. These results highlight the dual but separate role of Se, where inadequate doses may enhance OTA toxicity, while optimal supplementation may have a protective effect on hepatic lipid homeostasis. These findings can be used in the future progress of the mitigation strategy against OTA exposure in poultry nutrition.

Ochratoxin A (OTA), a mycotoxin commonly found in poultry feed, induces oxidative stress and disrupts redox homeostasis in vital organs such as the liver and kidneys. Selenium (Se), an essential trace element, may mitigate OTA-induced toxicity by supporting the antioxidant defense systems. This study investigated the short-term effects of dietary selenomethionine (SeMet) supplementation on OTA-induced oxidative and transcriptional responses in broiler chickens. Fifty-four 3-week-old birds were fed diets containing 2 mg/kg OTA, a target supplementation of 0.5 mg/kg Se (measured as 0.59 mg/kg as SeMet), or a combination of the two for five days. Liver and kidney samples were collected on Days 1 and 5 for biochemical and gene expression analyses. Exposure to OTA significantly modulated the expression of redox-sensitive transcription factors (NRF2, KEAP1), selenoproteins (GPX3, GPX4, SELK), and detoxification-related genes (AHR, AHRR, CYP1A2). SeMet alone enhanced selenoenzyme expression and antioxidant capacity, while co-exposure partially attenuated OTA-induced oxidative stress, resulting in more pronounced NRF2 activation in the kidneys and CYP1A2 induction in the liver. This is the first study to characterize the transcriptomic responses to OTA exposure in poultry within the first five days, providing novel insight into organ-specific mechanisms and emphasizing the epidemiological relevance of Se supplementation in mitigating the risk of feed contamination.

The present study evaluated the effects of dietary inclusion of Hermetia illucens (HI) and Tenebrio molitor (TM) larvae meals at 2% and 4% on growth performance, carcass yield, meat quality, blood parameters, and intestinal morphometry in broiler chickens. A total of 1750 one-day-old male Ross 308 broilers were assigned to five dietary treatments: a Control diet, or diets containing 2% or 4% of HI meal (HI2, HI4) or TM meal (TM2, TM4). Growth performance, feed intake (FI), feed conversation ratio (FCR), and mortality were unaffected by dietary treatments. Breast yield increased significantly in insect-fed groups (29.2–29.9%) compared with Control (27.6%). Birds fed HI4 exhibited lower breast pH (5.77 vs. 5.89) and increased cooking loss (29.2% vs. 27.3%), suggesting reduced WHC within acceptable ranges. Thigh meat showed dose-dependent lipid accumulation in insect-fed birds. Serum total cholesterol increased in TM-fed birds with elevated HDL-cholesterol, while LDL-cholesterol remained unaffected. TM meal specifically induced shorter ileal length compared with Control and HI-fed groups. Overall, both full-fat insect meals can be safely incorporated at low inclusion levels without adverse effects on broiler growth, health, or carcass quality.