Effects of spray-dried porcine plasma on growth performance, immune response, total antioxidant capacity, and gut morphology of nursery pigs.

Two experiments were conducted to evaluate the effects of spray-dried porcine plasma (SDPP) on growth performance, immunity, antioxidant capacity, and gut morphology of nursery pigs. In Exp. 1, 96 weaned pigs (Nebraska female × Danbred sire; 20 ± 1 d of age; initial BW = 6.06 ± 0.02 kg) were assigned to 16 pens and randomly allotted to the control (CTL; no SDPP) or the CTL + SDPP treatment in 2 phases (phase 1: d 0 to 14, 5% SDPP; phase 2: d 14 to 28, 2.5% SDPP). Blood samples were collected on d 0 and weekly thereafter to quantify IgG, IgA, and total antioxidant capacity. On d 14, pigs (n = 16; 8 pigs/treatment) were selected and euthanized for small intestine tissue and alveolar macrophage collection. On d 7, pigs fed SDPP had greater ADG, ADFI (P = 0.001), and G:F (P = 0.019) compared with CTL pigs. On d 28, pigs fed SDPP had greater BW (P = 0.024) and tended to have greater ADG (P = 0.074) and ADFI (P = 0.062) compared with CTL pigs. There were no differences between treatments for serum IgG, IgA, and total antioxidant capacity. On d 14, greater villus height (P = 0.011) and villus:crypt (P = 0.008) were observed in duodenal tissue sections obtained from SDPP-fed pigs compared with CTL pigs. To evaluate effects of SDPP on immune biomarkers, alveolar macrophages collected from 3 pigs/treatment on d 14 were cultured in vitro and challenged with lipopolysaccharide (LPS; 10 ng/mL). Therefore, 4 treatments included 1) CTL diet with no LPS, 2) CTL diet with LPS (CTL+), 3) SDPP diet with no LPS, and 4) SDPP diet with LPS. There were no diet effects on tumor necrosis factor-α gene expression or secretion by alveolar macrophages. For IL-10 gene expression, a diet × LPS interaction (P = 0.009) was observed where CTL+ had greater (P < 0.05) IL-10 mRNA abundance compared with other treatments. A second experiment was conducted to evaluate the in vitro effects of porcine plasma using model porcine jejunal epithelial cells (IPEC-J2). The treatments applied to the IPEC-J2 cells were 1) CTL, 2) CTL + 10% porcine plasma, 3) CTL + 5% porcine plasma, 4) CTL + 2.5% porcine plasma, or 5) CTL + 5% fetal bovine serum. The addition of porcine plasma increased (P < 0.001) proliferation of IPEC-J2 cells at 24 and 48 h following exposure to the respective treatments. In conclusion, dietary SDPP increased growth performance of nursery pigs during the first week postweaning and provide benefits to gut morphology possibly via increased proliferation of enterocytes.