Abstract
Background Xylanase and β-glucanase combination(XG)hydrolyzes soluble non-starch polysaccharides that are anti-nutritional compounds.This study aimed to evaluate the effects of increasing levels of XG on intestinal health and growth performance of nursery pigs.Methods Forty pigs(6.5±0.4 kg)were assigned to 5 dietary treatments and fed for 35 d in 3 phases(11,9,and 15 d,respectively).Basal diets mainly included corn,soybean meal,and corn distiller's dried grains with solubles,contained phytase(750 FTU/kg),and were supplemented with 5 levels of XG at(1)0,(2)280TXU/kg xylanase and 125TGU/kgβ-glucanase,(3)560 and 250,(4)840 and 375,or(5)1,120 and 500,respectively.Growth performance was measured.On d 35,all pigs were euthanized and jejunal mucosa,jejunal digesta,jejunal tissues,and ileal digesta were collected to determine the effects of increasing XG levels and XG intake on intestinal health.Results Increasing XG intake tended to quadratically decrease(P=0.059)viscosity of jejunal digesta(min:1.74 mPa-s at 751/335(TXU/TGU)/kg).Increasing levels of XG quadratically decreased(P＜0.05)Prevotellaceae(min:0.6％at 630/281(TXU/TGU)/kg)in the jejunal mucosa.Increasing XG intake quadratically increased(P＜0.05)Lactobacil-laceae(max:40.3％at 608/271(TXU/TGU)/kg)in the jejunal mucosa.Increasing XG intake quadratically decreased(P＜0.05)Helicobacteraceae(min:1.6％at 560/250(TXU/TGU)/kg)in the jejunal mucosa.Increasing levels of XG tended to linearly decrease(P=0.073)jejunal IgG and tended to quadratically increase(P=0.085)jejunal villus height to crypt depth ratio(max:2.62 at 560/250(TXU/TGU)/kg).Increasing XG intake tended to linearly increase the appar-ent ileal digestibility of dry matter(P=0.087)and ether extract(P=0.065).Increasing XG intake linearly increased(P＜0.05)average daily gain.Conclusions A combinational use of xylanase and β-glucanase would hydrolyze the non-starch polysaccharides frac-tions,positively modulating the jejunal mucosa-associated microbiota.Increased intake of these enzyme combina-tion possibly reduced digesta viscosity and humoral immune response in the jejunum resulting in improved intestinal structure,and ileal digestibility of nutrients,and finally improving growth of nursery pigs.The beneficial effects were maximized at a combination of 550 to 800TXU/kg xylanase and 250 to 360TGU/kg β-glucanase.
基金项目
North Carolina Agricultural Foundation(Raleigh,NC,USA)(660101)
USDA-NIFA(Washing DC,USA)(Hatch 02893)
BASF SE(Ludwigshafen,Germany)()
万方数据