Differential Dispositions of Deoxynivalenol in Nursery and Finishing Pigs under Sulfonation Treatment Revealed by Metabolomic Profiling

Deoxynivalenol (DON) is a highly reactive epoxy-sesquiterpenoid mycotoxin commonly present in cereal feed ingredients. Dietary DON contamination negatively affects feed intake, growth, and health status in all stages of swine production. Both in vivo biotransformation, including somatic xenobiotic metabolism and microbial metabolism, and ex vivo chemical mitigation reactions, such as bisulfite-based sulfonation, have been shown to reduce the reactivity and bioavailability of DON in pigs. However, the influences of age and maturation on the disposition of DON and its chemical mitigation in pigs have not been examined in detail. The objective of the current study was to evaluate growth performance and the metabolomic profiling of DON and its derivatives in feeds, feces, and urine through two feeding trials. In a 21-day nursery trial, 4 groups of pigs (n = 12/group) were fed low- and high-dose DON with and without 0.25% Notox D, a bisulfite agent. In a 49-day finishing trial, 5 groups of pigs (n = 12/group) were fed the DON-contaminated feed without a mitigant, or with 0.25% Notox D, and 0.25%, 0.50%, and 0.75% sodium metabisulfite. The performance results showed that sulfonation treatment restored the growth of nursery pigs under the high-dose DON exposure (3.7 ppm), but there was no difference in pig growth under the low-dose DON exposure (0.8 ppm for nursery pigs and 1.2 ppm for finishing pigs). Metabolomic profiling indicated that finishing pigs were more capable than nursery pigs in the microbial conversion of DON to deepoxy-deoxynivalenol (DOM), DOM absorption, and somatic production of their glucuronides. Bisulfite agents effectively and dose-dependently decreased DON in pig feeds by forming DON sulfonates (DON-S), which were further enriched and concentrated in feces. The decreases of free and total DON in urine after sulfonation treatment were correlated with the improved growth performance in nursery pigs. Overall, these results revealed extensive interactions among maturation, DON disposition, and sulfonation treatment in pigs and hence warrant further investigations to establish the reference values on the age of pigs, the level of DON contamination, and the dose of bisulfite agents to guide the mitigation practices in swine production.