294 The effects of titrated levels of water soluble zinc amino acid complex on immune response of nursery pigs

Abstract

Abstract Previously, we reported that supplementing titrated levels of a water soluble zinc amino acid complex (ProPath®Zn LQ, Zinpro Corporation, Eden Prairie, MN) via water (0 to 80 mg/L) to nursery pigs resulted in a lower inflammatory response after LPS challenge. To evaluate the efficacy of higher titrated levels, 280 pigs (5.5 kg BW; 19-d old) were allotted randomly to water treatments: 0, 40, 80 and 160 mg Zn/L of water (7 pens/treatment; 10 pigs/pen). Pigs were fed corn-soybean meal based diets with added Zn as ZnO or Cu as CuSO4: Phase 1 (2,500 mg Zn/kg; d 1–7), Phase 2 (1,750 mg Zn/kg; d 7–14), Phase 3 (200 mg Cu/kg; d 14–23), and Phase 4 (200 mg Cu/kg; d 23–42). At d 23, pigs were challenged by i.m. injection of lipopolysaccharide (12 µg/kg BW). Blood, BW, and rectal temperature (RT) were obtained from two pigs per pen at h 0, 3, and 12 of the challenge. Increasing water zinc resulted in linear reductions in RT (P = 0.02) and serum TNF-α concentration (P = 0.05) at h 0 prior to LPS injection. Post-LPS injection, increasing water zinc decreased linearly RT at h 3 (P = 0.01) and serum Zn:Cu ratio at h 3 (P = 0.04) and 12 (P = 0.01), and decreased serum TNF-α concentration at all hours (quadratic, P < 0.05). Additionally, increasing water zinc tended (linear, P = 0.07) to attenuate the decrease in BW following LPS from h 0–12. However, there were no effects on serum and salivary CRP concentrations (P > 0.05) within 12 hours of LPS challenge. At d 42, salivary CRP concentration decreased (quadratic, P = 0.03) with increasing zinc. In conclusion, supplementing ProPath®Zn LQ via drinking water to nursery pigs mitigated the febrile response and decreased cytokine production during an acute immune challenge.