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

Authors: WILSON, VICTORIA - Iowa State University; RAMIREZ, SHELBY - Biomin America, Inc; MURUGESAN, GANAPATHI - Biomin Research Center; HOFSTETTLER, URSULA - Biomin Research Center; Kerr, Brian

Submitted to: Translational Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/26/2022
Publication Date: 9/27/2022
Citation: Wilson, V.C., Ramirez, S.M., Murugesan, G.R., Hofstettler, U., Kerr, B.J. 2022. Effects of feeding variable levels of mycotoxins with or without a mitigation strategy on growth performance, gut permeability, and oxidative biomarkers in nursery pigs. Translational Animal Science. 6(3). Article txac126. https://doi.org/10.1093/tas/txac126.
DOI: https://doi.org/10.1093/tas/txac126

Interpretive Summary: Mycotoxins are commonly found in grains or grain by-products fed to swine with deoxynivalenol being the most common mycotoxin found in cereal grains produced in the Midwest United States. When pigs are fed diets containing moderate levels of deoxynivalenol, their rate of growth is reduced, the permeability of their intestines to digestive compounds passing through them is increased, and measures of metabolic stress in their body is increased. To counteract these negative effects, diets fed to pigs often have compounds added to help mitigate these negative effects. The current study was conducted to determine the effects of diets containing low or high levels of deoxynivalenol in combination with a mycotoxin mitigating compound on growth performance, intestinal permeability, and metabolic stress in nursery pigs. Data from this experiment indicate that feeding pigs diets containing elevated levels of deoxynivalenol decreased rates of growth but had little effect on intestinal permeability or measures of metabolic stress. The inclusion of a mycotoxin mitigating compound in the diet improved feed intake in pigs fed diets high in deoxynivalenol but had no consistent effect on metabolic stress or intestinal permeability. This information is important for nutritionists at universities, feed companies, and pig production facilities for the determination of the impact of deoxynivalenol and mycotoxin mitigating compounds on pig performance, gastrointestinal function, and metabolic stress.

Technical Abstract: Mycotoxins (MTX) such as deoxynivalenol (DON), fumonisin, and zearalenone are often present in corn and corn by-products produced in the Midwestern United States. Previous literature has shown that MTX can negatively impact growth performance and health status in swine and poultry. The objectives of the present experiment were to determine how high levels (> 2.5 mg/kg diet) of DON, in conjunction with other naturally occurring MTX, would impact growth, intestinal integrity, and oxidative status, with or without a mitigation strategy, in nursery pigs. One-hundred and five, mixed sex pigs (initial BW 5.5 ± 0.52 kg) were randomly allotted to 35 pens with 3 pigs per pen and fed dietary treatments for 45 d. Dietary 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 with 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 level 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 level and BPL addition 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 level and BPL inclusion, or an effect of MTX level or BPL inclusion on DNA damage as measured by 8-hydroxy-2’dexoxyguanosine (P = 0.59). There was no interaction between MTX level and BPL inclusion, 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 level and BPL inclusion, or an effect of MTX level or BPL inclusion 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 ere 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.