Dose-response effects of corn-derived deoxynivalenol on nursery pig feed intake and growth performance

Deoxynivalenol (DON) is a trichothecene mycotoxin commonly contaminating swine diets and is known to impair nursery pig performance through anorectic effects. The objective of this study was to characterize the dose-response effects of increasing dietary DON concentrations (0.2 to 5.1 mg/kg) that were naturally added through increasing levels of DON-contaminated corn on growth performance in modern nursery pigs using a seven-point titration design. A total of 112 pigs (9.1 ± 0.37 kg BW) were assigned to one of seven dietary treatments (n = 8 pens/treatment; 2 pigs/pen) and fed experimental diets for 24 d (Phase 1: d 0-14; Phase 2: d 14-24). Growth performance declined linearly during both Phase 1 and Phase 2 (P < 0.001). Across the 24-d period, increasing DON reduced overall BW, ADG, and ADFI in a linear manner (P < 0.001), with no quadratic responses detected (P > 0.100) DON concentration explained 39%, 48%, and 58% of the variation in final BW, ADG, and ADFI, respectively. Each 1 mg/kg increase in DON was associated with a 1.13 kg reduction in final BW, a 0.04 kg/d reduction in ADG, and a 0.07 kg/d reduction in ADFI. Overall Gain:Feed was not linearly related to DON concentration (P = 0.214). Two-segmented and linear-plateau regression analysis provided minimal improvement over linear models, indicating limited to no evidence for a biological breakpoint within the evaluated range. These findings demonstrate a clear, linear, dose-dependent suppression of voluntary feed intake and growth performance in nursery pigs exposed to 0.2 to 5.1 mg/kg DON, without evidence of a discrete intake threshold.