PSXIII-3 - Trace mineral source matters to reduce trace mineral excretion and maximize mineral retention in growing pigs

Abstract: The study objective was to determine differences between a methionine hydroxy analog chelated trace mineral blend (MHAC; MINTREX Trace Minerals [Novus International Inc., St. Charles, MO]) and sulfate (inorganic) sources of trace minerals (ITM) on the apparent total tract digestibility (ATTD) of dry matter (DM) and mineral utilization in growing pigs. A total of 10 growing gilts (PIC North America, Hendersonville, TN) weighing 50.5± 2.6kg were randomly assigned to either an MHAC or an ITM dietary treatment. Supplemental Zn, Cu, and Mn levels for both treatments were 100, 20, and 40 mg/kg, respectively. Diets were corn-soy-based with phytase added to release 0.09% standardized total tract digestible P. Pigs were housed in metabolism crates for 7-d, including 5 for adaptation and 2 for total fecal and urine collection. Data were analyzed using the MIXED procedure of SAS. Results showed that pigs fed MHAC had a numerical increase in the ATTD of DM compared with ITM (90.9 vs. 89.4%; P=0.180). Pigs fed MHAC had greater ATTD of Zn than those fed ITM (36.4 vs. 16.8%; P=0.013), greater Zn retention (87.1 vs. 36.9 mg/d; P=0.011), and lower Zn excretion than those fed ITM (159.1 vs. 209.3mg/d; P=0.013). Pigs fed MHAC had increased Zn retention:intake compared with ITM (0.353 vs. 0.152; P = 0.014). There was a numerical increase in Zn retention:absorption in pigs fed MHAC compared with ITM (0.977 vs. 0.796; P=0.128). Pigs fed MHAC had greater ATTD of Cu than those fed ITM (52.5 vs. 30.7%; P=0.012), had increased Cu retention (25.6 vs. 14.4mg/d; P=0.012) and less Cu excretion than those fed ITM (24.1 vs. 35.3mg/d; P = 0.016). Pigs fed MHAC had increased Cu retention:intake compared with ITM (0.513 vs. 0.293; P = 0.017) and tended to increase Cu retention: absorption (0.980 vs. 0.944; P = 0.057). Pigs fed MHAC had greater ATTD of Mn than ITM (35.8 vs. 14.5%; P=0.019), had increased Mn retention (42.4 vs. 16.5mg/d; P=0.017), and less Mn excretion than ITM (77.2 vs. 103.0mg/d; P=0.017). Pigs fed MHAC had increased Mn retention:intake compared with ITM (0.353 vs. 0.141; P=0.018). There were no differences between MHAC and ITM in Mn retention:absorption (0.986 vs. 0.986; P=0.993). Pigs fed MHAC had a numerical increase in the ATTD of P (69.3 vs. 62.9%; P=0.373), numerically less P excretion (2.94 vs. 3.57g/d; P=0.348), and numerically greater P retention (6.44 vs. 5.80; P=0.376) than those fed ITM. In conclusion, pigs fed MHAC had greater Zn, Cu, and Mn availability than ITM. This is likely due to the distribution and utilization of these trace minerals where they are needed. Furthermore, MHAC decreased the excretion of these minerals to nourish the pigs and reduce their impact on the environment through nutrient losses.