Invited review: Remediation strategies for mycotoxin control in feed.

Mycotoxins are secondary metabolites of different species of fungi. Aflatoxin B1 (AFB1), deoxynivalenol (DON), zearalenone (ZEN) and fumonisin B1 (FB1) are the main mycotoxins contaminating animal feedstuffs. These mycotoxins can primarily induce hepatotoxicity, immunotoxicity, neurotoxicity and nephrotoxicity, consequently cause adverse effects on the health and performance of animals. Therefore, physical, chemical, biological and nutritional regulation approaches have been developed as primary strategies for the decontamination and detoxification of these mycotoxins in the feed industry. Meanwhile, each of these techniques has its drawbacks, including inefficient, costly, or impractically applied on large scale. This review summarized the advantages and disadvantages of the different remediation strategies, as well as updates of the research progress of these strategies for AFB1, DON, ZEN and FB1 control in the feed industry.

Occurrence of Aflatoxin B1, deoxynivalenol and zearalenone in feeds in China during 2018-2020.

BACKGROUND: The current study was conducted to investigate the individual and combined occurrence of aflatoxin B1 (AFB1), deoxynivalenol (DON) and zearalenone (ZEN) in feeds from various Provinces of China during 2018 to 2020. A total of 3,507 feed samples, including 2,090 feed ingredients and 1,417 complete feed samples, were collected from different areas of China for mycotoxins analysis. RESULTS: The individual contamination of AFB1, DON and ZEN were present in more than 81.9%, 96.4% and 96.9% of feed samples, respectively, with average concentration ranges of AFB1 between 1.2-27.4 µg/kg, DON between 458.0-1,925.4 µg/kg and ZEN between 48.1-326.8 µg/kg. Notably, 0.9%, 0.5% and 0.1% of feed ingredients, and 1.2-12.8%, 0.9-2.9% and 0-8.9% of complete feeds for pigs, poultry and ruminants with AFB1, ZEN and DON that exceeded China's safety standards, respectively. Moreover, more than 81.5% of feed ingredients and 95.7% of complete feeds were co-contaminated with various combinations of these mycotoxins. CONCLUSION: This study indicates that the feeds in China were universally contaminated with AFB1, DON and ZEN during the past 3 years. These findings highlight the significance of monitoring mycotoxin contaminant levels in the domestic animal feed, and the importance of carrying out feed administration and remediation strategies for mycotoxin control.

The response of glandular gastric transcriptome to T-2 toxin in chicks.

This study was conducted to determine the effect of T-2 toxin on the transcriptome of the glandular stomach in chicks using RNA-sequencing (RNA-Seq). Four groups of 1-day-old Cobb male broilers (n = 4 cages/group, 6 chicks/cage) were fed a corn-soybean-based diet (control) and control supplemented with T-2 toxin at 1.0, 3.0, and 6.0 mg/kg, respectively, for 2 weeks. The histological results showed that dietary supplementation of T-2 toxin at 3.0 and 6.0 mg/kg induced glandular gastric injury including serious inflammation, increased inflammatory cells, mucosal edema, and necrosis and desquamation of the epithelial cells in the glandular stomach of chicks. RNA-Seq analysis revealed that there were 671, 1393, and 1394 genes displayed ≥2 (P < 0.05) differential expression in the dietary supplemental T-2 toxin at 1.0, 3.0, and 6.0 mg/kg, respectively, compared with the control group. Notably, 204 differently expressed genes had shared similar changes among these three doses of T-2 toxin. GO and KEGG pathway analysis results showed that many genes involved in oxidation-reduction process, inflammation, wound healing/bleeding, and apoptosis/carcinogenesis were affected by T-2 toxin exposure. In conclusion, this study systematically elucidated toxic mechanisms of T-2 toxin on the glandular stomach, which might provide novel ideas to prevent adverse effects of T-2 toxin in chicks.

A Novel Modified Hydrated Sodium Calcium Aluminosilicate (HSCAS) Adsorbent Can Effectively Reduce T-2 Toxin-Induced Toxicity in Growth Performance, Nutrient Digestibility, Serum Biochemistry, and Small Intestinal Morphology in Chicks.

The objective of this study was to evaluate the ability of a modified hydrated sodium calcium aluminosilicate (HSCAS) adsorbent to reduce the toxicity of T-2 toxin in broilers. Ninety-six one-day-old male broilers were randomly allocated into four experimental groups with four replicates of six birds each. The four groups, 1-4, received a basal diet (BD), a BD plus 6.0 mg/kg T-2 toxin, a BD plus 6.0 mg/kg T-2 toxin with 0.05% modified HSCAS adsorbent, and a BD plus 0.05% modified HSCAS adsorbent, respectively, for two weeks. Growth performance, nutrient digestibility, serum biochemistry, and small intestinal histopathology were analyzed. Compared to the control group, dietary supplementation of T-2 toxin decreased (p < 0.05) body weight gain, feed intake, and the feed conversion ratio by 11.4%-31.8% during the whole experiment. It also decreased (p < 0.05) the apparent metabolic rates of crude protein, calcium, and total phosphorus by 14.9%-16.1%. The alterations induced by T-2 toxin were mitigated (p < 0.05) by the supplementation of the modified HSCAS adsorbent. Meanwhile, dietary modified HSCAS adsorbent supplementation prevented (p < 0.05) increased serum aspartate aminotransferase by T-2 toxin at d 14. It also prevented (p < 0.05) T-2 toxin-induced morphological changes and damage in the duodenum, jejunum, and ileum of broilers. However, dietary supplementation of the modified HSCAS adsorbent alone did not affect (p > 0.05) any of these variables. In conclusion, these findings indicate that the modified HSCAS adsorbent could be used against T-2 toxin-induced toxicity in growth performance, nutrient digestibility, and hepatic and small intestinal injuries in chicks.

Individual and Combined Occurrence of Mycotoxins in Feed Ingredients and Complete Feeds in China.

The objective of this study was to investigate the individual and combined contamination of aflatoxin B1 (AFB1), zearalenone (ZEN) and deoxynivalenol (DON) in feedstuffs from different Provinces of China between 2016 and 2017. A total of 1569 samples, including 742 feed ingredients and 827 complete pig feed samples, were collected from various regions of China for mycotoxins analysis. The results showed that individual occurrence rates of AFB1, ZEN, and DON were more than 83.3%, 88%, and 74.5%, respectively, in all the tested samples. DON was the most prevalent contaminant, followed by ZEN and AFB1, with the average concentrations ranging from 450.0-4381.5 µg/kg, 2.3-729.2 µg/kg, and 1.3-10.0 µg/kg, respectively. Notable, 38.2%, 10.8%, and 0.6% of complete pig feeds were contaminated with DON, ZEN, and AFB1 over China's regulatory limits, respectively. Moreover, over 75.0% analyzed samples were co-contaminated with two or three mycotoxins. In conclusion, the current study revealed that the feedstuffs in China were severely contaminated with DON, followed by ZEN and AFB1 during the past two years. These findings highlight the importance of monitoring mycotoxins in livestock feed and implementing feed management and bioremediation strategies to reduce mycotoxin exposure.