Effect of long-term feeding of graded levels of deoxynivalenol on performance, nutrient utilization, and organ health of grower-finisher pigs (35 to 120 kg)

Abstract

The objective of this study was to evaluate the effect of long-term feeding of graded levels of deoxynivalenol (DON) on performance, nutrient utilization, and organ health of grower-finisher pigs. A total of 240 mixed-sex grower-finisher pigs (35.9 ± 1.1 kg initial body weight, BW) were randomly assigned to 1 of 4 dietary treatments (6 pigs/pen; 10 pens/treatment) for 77 d. Diets consisted of a control diet without DON (CONT) and diets containing 1, 3, or 5 ppm DON (DON1, DON3, or DON5). Nitrogen-balance was determined in 1 pig/pen during weeks 6 and 12 of the study. Growth performance measures were taken weekly for average daily feed intake (ADFI), average daily gain (ADG), and gain:feed (GF) until day 77. Blood samples were collected on days 0, 14, 42, 56, and 84 from 1 pig/pen for analysis of indicators of liver and kidney function. On day 7, ADG and ADFI for pigs fed DON3 and DON5 diets were lower (P < 0.05) compared with DON1- and CONT-fed pigs. Overall, ADG and ADFI (days 0 to 77) were lower in DON3- and DON5-fed pigs compared with CONT and DON1 pigs (P < 0.05), with no difference in GF (P > 0.05). Final BW was reduced in DON3- and DON5-fed pigs (P < 0.05) compared with CONT and DON1, which were not different (P > 0.05). No significant (P > 0.05) treatment effects were observed on carcass characteristics. In the grower-phase, protein deposition (PD) was reduced in DON3 and DON5 pigs compared with CONT and DON1 pigs (P < 0.05). In the finisher phase, PD was not affected by dietary treatment (P > 0.05). There was no effect of dietary treatment on the majority of selected serum chemistry (P > 0.05). In summary, pigs exposed to diets containing > 1 ppm DON had reduced growth performance with little or no effect on nitrogen utilization, organ health, or carcass characteristics, suggesting that the negative effects of DON may be largely due to depressed feed intake.

Keywords: average daily feed intake; average daily gain; deoxynivalenol; feed efficiency; nitrogen balance; swine.

Figure 1.

Regression analysis of the relationship between deoxynivalenol (DON) intake and ADG in pigs fed DON-contaminated diets during the grower phase days 0 to 42 (A), finisher phase days 43 to 77 (B), and overall days 0 to 77 (C). Each point on the graph represents an experimental pen (n = 10 pens/treatment). Data are expressed as the DON intake (mg/d) based on ADFI and the bodyweight change of the DON treated groups relative to the control (CONT) group of pigs. The coefficient of determination (R²) of the regression curve is 0.26, 0.10, and 0.35 for grower phase, finisher phase, and overall, respectively, at P < 0.05.

Figure 2.

Relationship between DON intake and BW change in pigs fed DON-contaminated diets relative to pigs fed diets containing no DON (CONT) during the grower phase days 0 to 42 (A), finisher phase days 43 to 77 (B), and overall days 0 to 77 (C). Data are expressed as the DON intake (mg/d) based on average daily feed intake and the bodyweight change of the DON treated groups relative to the control (CONT) group of pigs. Each point on the graph represents an experimental pen (n = 10 pens/treatment). The coefficient of determination (R²) of the regression curve is 0.14, 0.001, and 0.22 for grower phase, finisher phase, and overall, respectively, at P < 0.05.