Abstract It is well established that bioavailability of organic trace minerals (OTM) is higher than their inorganic counterparts. Inorganic trace minerals (ITM) release reactive free ions that bind to dietary components, affecting the stability of vitamins, minerals, and phytase in the premix, interfering with the pig's absorption of nutrients during digestion. OTM are less likely to bind to other dietary components because they are already complexed with organic agents, which confers greater bioavailability and stability, allowing a lower inclusion rate. OTM are commonly used in sow and nursery pig diets, but their use for grow-finish pigs is less researched. Therefore, two commercial scale studies were conducted to evaluate the growth performance and carcass characteristics of grow-finish pigs fed with OTM. In Exp 1, 2,168 pigs (initial BW 23.2 kg) were used in a 117-d trial. Pigs were placed in pens with 25 or 26 pigs each and allotted to 1 of 5 dietary treatments with 18 replicates per treatment. Treatments consisted of 1) Industry levels of ITM (Cu, Fe, Mn, Se, and Zn in sulphate and oxide forms), 2) NRC (2012) levels of ITM, 3) 33%, 4) 66%, and 5) 100% of NRC (2012) Cu, Fe, Mn, and Zn proteinates (Bioplex®; Alltech, Nicholasville, KY) and 0.3 ppm of Se yeast (Sel-Plex®; Alltech, Nicholasville, KY). In Exp 2, 1,188 pigs (initial BW 25.9 kg) were used in a 120-d trial. Pigs were placed in pens with 24 or 25 pigs each and allotted to 1 of 2 dietary treatments with 24 replicates per treatment. Treatments consisted of 1) Industry levels of ITM (Cu, Fe, Mn, Se, and Zn) and 2) 66% of NRC (2012) Cu, Fe, Mn, and Zn proteinates (BioPlex®; Alltech, Nicholasville, KY) and 0.3 ppm of Se yeast (Sel-Plex®; Alltech, Nicholasville, KY). Pigs were fed a six-phase corn and soybean meal-based diet program formulated to meet or exceed NRC (2012) nutrient requirements. In both experiments, no differences (P 0.10) in growth performance, final body weight, or carcass weight were observed. However, in Exp 1, pigs fed 66% NRC OTM tended (P = 0.067) to have lower backfat compared to other treatments. Also, pigs fed 66% NRC OTM had the highest (P 0.001) loin depth and lean percentage, while those fed 33% or 100% NRC OTM also outperformed all ITM groups in these traits. In Exp 2, similar results were found, where pigs fed 66% NRC OTM had greater loin depth (P 0.001) and lean percentage (P = 0.003) than those fed industry ITM levels. Collectively, these data indicate that a lower inclusion rate of Cu, Fe, Mn, and Zn proteinates, along with Se yeast, can replace ITM without impairing growth performance while supporting carcass quality.
Faccin et al. (Wed,) studied this question.