Abstract This study evaluated the effects of Zn, Cu, and Mn as methionine hydroxy analogue bis-chelates (MHAC) at lower inclusion rates than inorganic trace minerals (ITM) on growth performance, health, and economic parameters of growing–finishing pigs. A 118-d study was conducted using 1, 069 pigs (PIC Sire 337 × PIC Maternal 1050) with approximately equal numbers of barrows and gilts. Pen was the experimental unit with 21 pens per treatment. Pigs weighed 30. 7 + 0. 84 kg at trial start (P = 0. 97). Pens were assigned to one of two diets differing in Zn, Cu and Mn program. The ITM pens received diets supplemented with 100 mg/kg Zn as ZnO, 20 mg/kg Cu as CuSO4 and 25 mg/kg Mn as MnO. The MHAC pens received diets in which supplemental Zn, Cu and Mn were 40 mg/kg, 10 mg/kg and 20 mg/kg supplemented as MHAC bis-chelates. For both treatments, the only other source of Zn, Cu and Mn was from the ingredients and a common water source. The supplemental level of respective Zn, Cu and Mn remained constant throughout the study. Pigs had ad libitum access to feed and water. Diets were corn-soybean meal-corn DDGs based in meal form supplemented with phytase. Data was analyzed with the MIXED procedure of SAS with dietary treatment as fixed effect and BW block as the random effect. For all binomial responses, Chi-square analysis was used. Over the 118-d trial, adjusted ADG was 1. 4% greater (0. 846 vs. 0. 834 kg/d; P = 0. 08) for MHAC. The greater growth rate was driven by greater ADFI (2. 29 vs. 2. 25 kg/d; P = 0. 01) for MHAC. The greater ADG driven by greater ADFI resulted in no difference in gain to feed (0. 37; P = 0. 64). Meeting the Zn, Cu and Mn need as MHAC resulted in lower morbidity (4. 66 vs. 7. 71%; P = 0. 04) and total removals (6. 7 vs. 10. 1%; P = 0. 04). The MHAC mineral program resulted in more pigs finished (93. 3 vs. 89. 9%; P = 0. 04) and more pigs sold to primary market (89. 0 vs. 85. 5%; P = 0. 09). The resulting MHAC impacts on closeout measures included greater closeout ADG (0. 812 vs. 0. 779 kg/d; P = 0. 01) and numerically better gain to feed (0. 355 vs. 0. 346; P = 0. 19). Economic return was numerically greater for the MHAC treatment using September 2025 ingredient prices, pig cost and carcass value. Margin over feed cost was 3. 82/pig greater (P = 0. 13) while income over feed, facility and pig cost was 4. 81/pig greater for MHAC. These results demonstrate that available mineral source may be a bigger determinant of growing pig performance, health and economic return than total mineral.
Camargo et al. (Wed,) studied this question.