The effect of naturally occurring levels of multiple mycotoxins on growth performance and carcass parameters of grow-finish pigs

Mycotoxins may not be an issue every year, but the proper environmental conditions can cause a spike in contaminated grains and cause severe economic impact on pork producers. The objective of this study was to determine the effect of naturally occurring infections of deoxynivalenol, zearalenone and fumonisins (DZF) on growth performance and carcass parameters in grow/ finish pigs. One hundred pigs (BW 34.0 ± 0.9 kg; L337 x Camborough, PIC, Hendersonville, TN) were randomly assigned to 1 of 2 dietary treatments with 10 split-sex pens/treatment. The control diet (CTL) contained low levels of DZF and the CTL+DFZ diet contained high levels of DZF. Diets were fed in 4 phases over the 126-d experiment period. The CTL diet contained 1.6, 1.6, 1.8 and 1.2 mg deoxynivalenol/kg and CTL+DZF contained 9.2, 6.9, 5.8 and 3.8 mg deoxynivalenol/kg in the 4 diet phases, respectively. The CTL contained 0.30, 0.32, 0.51 and 0.32 mg zearalenone/kg and 0.7, 0.8, 0.8 and 0.9 mg total fumonisins/kg; CTL+DFZ contained 0.59, 0.72, 0.86 and 0.57 mg zearalenone/kg and 1.0, 1.1, 1.2 and 0.9 mg total fumonisins/kg for phases one through four, respectively. Data were analyzed using PROC MIXED of SAS (9.4) with treatment, sex, and their interaction as fixed effects. Compared to CTL, feeding CTL+DFZ decreased final BW (130.3 vs 120.5 kg; P< 0.001), ADG (0.95 vs 0.79 kg/d; P< 0.001), ADFI (2.73 vs 2.49 kg/d; P=0.016), and G:F (0.35 vs 0.32; P=0.043). Feeding CTL+DFZ decreased HCW (92.3 vs 89.4 kg; P=0.024) and increased dressing percentage (70.9 vs 74.3%; P=0.009) and tended to reduce loin depth (7.0 vs 6.8 cm; P=0.057) compared to CTL. Diet did not affect backfat depth or lean percentage (P >0.10). In conclusion, diets naturally contaminated with multiple mycotoxins reduced growth performance and adversely affected carcass parameters; pigs did not adapt over time to the mycotoxins.