MicroRNAs as Early Biomarkers to Identify Fumonisins, Deoxynivalenol, and Zearalenone Exposure in Broiler Chickens

Authors: KAPPARI, LAHARIKA - University Of Georgia; APPLEGATE, TODD - University Of Georgia; Glenn, Anthony - Tony; Bakre, Abhijeet; Shanmugasundaram, Revathi

Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/28/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary: n/a

Technical Abstract: The Fusarium mycotoxins Fumonisin B1 (FUM), Deoxynivalenol (DON), and Zearalenone (ZEA) pose a significant challenge to the poultry industry. Identifying early biomarkers of mycotoxin exposure will facilitate timely intervention strategies. MicroRNAs (miRNAs) are potential molecular biomarkers to diagnose mycotoxicosis because miRNAs exhibit alterations earlier than clinical symptoms will manifest. Hence, this study aimed to identify the miRNA expression profiles in chickens exposed to subclinical doses of combined FUM, DON, and ZEA. A total of 720 one-day-old broiler chicks were assigned to six treatments. (1) Control diet (0.6mg FUM + 0.4mg DON + 0.0mg ZEA); (2) 21mg FUM + 3mg DON +1.0mg ZEA; (3) 17mg FUM +1.0mg DON +0.2mg ZEA; (4) 9mg FUM + 3.5mg DON + 0.7mg ZEA; (5) 5mg FUM + 0.4mg DON + 0.1mg ZEA; and (6) 2mg FUM + 2.5mg DON + 0.9mg ZEA per kg diet. Growth performance metrics were recorded for 35 days, and liver samples were collected on day 14 for miRNA expression analysis to detect early mycotoxicoses. The data was analyzed using a one-way ANOVA. At day 35, birds in the highest mycotoxin treatment group (21mg FUM + 3mg DON + 1.0mg ZEN/kg diet) had significantly lower body weight gain (BWG) by 10.5% and an increased feed conversion ratio (FCR) by 37 points compared to the control group (P = 0.05). Chickens in the lowest mycotoxin treatment group (2mg FUM + 2.5mg DON + 0.9mg ZEN/kg diet) had significantly decreased the BWG (P < 0.05) by 6.0%, increased the FCR by 3 points (P > 0.05) compared to the control group. To analyze miRNA expression by real-time PCR, microRNA was extracted from 14-day-old broiler chicken liver tissues, reverse transcribed into cDNA using a specific miRNA cDNA synthesis kit, and a total of nine genes were selected and amplified using specific forward primers obtained from previous chicken miRNA studies and a universal reverse primer, with expression levels normalized to the reference gene, U6. Treatment with 21mg FUM + 3mg DON + 1.0mg ZEA per kg diet led to substantial upregulation of hepatic miR-7a-5p, miR-19b-3p, and miR-217-5p (P < 0.05). Conversely, treatment with 2mg FUM + 2.5mg DON + 0.9mg ZEA per kg diet resulted in notable downregulation of these above microRNAs. Histopathological examinations showed significant liver morphological changes in mycotoxin-exposed birds. In conclusion, even subclinical doses of combined mycotoxins negatively impact broiler growth, and liver microRNA expression profiles and liver microRNA profiles can serve as biomarkers for mycotoxin exposure as early as 14 days of exposure. Keywords: Biomarker, Broiler, MicroRNAs, Mycotoxins