Effects of feeding variable levels of mycotoxins with or without a mitigation strategy on growth performance, gut permeability, and oxidative biomarkers in nursery pigs.

The objectives were to determine how high levels (> 2.5 mg/kg diet) of deoxynivalenol (DON), in conjunction with other naturally occurring mycotoxins (MTX) would impact growth, intestinal integrity, and oxidative status, with or without a mitigation strategy, in nursery pigs. One-hundred and five pigs (5.5 ± 0.52 kg) were randomly allotted to 35 pens and fed dietary treatments for 45 d. Treatments were factorially arranged with the inclusion of MTX being low (L-MTX; < 1 mg/kg diet) or high (H-MTX; > 2.5 mg/kg diet) in combination with no mitigation strategy or the inclusion of a mitigation strategy (Biofix® Plus, BPL; 1.5 mg/kg diet). There was no interaction between MTX level and BPL inclusion on average daily gain (ADG) or gain to feed ratio (GF), (P > 0.10). Compared to pigs fed diets containing L-MTX, feeding pigs diets containing H-MTX decreased ADG and GF (P < 0.05). The addition of BPL had no effect on ADG (P > 0.10), but improved GF (P = 0.09). There was an interaction between MTX and BPL on average daily feed intake (ADFI), where the addition of BPL had no effect on ADFI of pigs fed L-MTX diets but improved ADFI of pigs fed H-MTX diets (P = 0.09). An interaction was detected between MTX and BPL on protein oxidation as measured by plasma protein carbonyls (PC, P = 0.01), where the inclusion of BPL decreased plasma PC in pigs fed H-MTX diets to a greater extent than pigs fed the L-MTX diets. There was no interaction between MTX and BPL, or an effect of MTX or BPL on DNA damage as measured by 8-hydroxy-2'dexoxyguanosine (P > 0.10). There was no interaction between MTX and BPL, or a BPL effect on lipid damage as measured by thiobarbituic acid reactive substances (TBARS, P > 0.10), but pigs fed diets containing H-MTX exhibited lower concentrations of plasma TBARS (P = 0.07) compared to pigs fed L-MTX diets. There was no interaction between MTX and BPL, or an effect of MTX or BPL on plasma lactulose and mannitol ratio as a measure of intestinal permeability (P > 0.10). In conclusion, feeding H-MTX decreased ADG and GF, decreased plasma TBARS, but did not affect plasma 8-hydroxy-2'dexoxyguanosine or plasma LM ratio. The inclusion of a mitigation strategy improved ADFI when pigs were fed H-MTX diets and improved GF regardless of MTX level. Addition of a mitigation strategy also reduced plasma protein damage but did not affect indicators of DNA or lipid damage or affect gastrointestinal integrity. Published by Oxford University Press for the American Society of Animal Science 2022.