title: Innate immune response to yeast-derived carbohydrates in broiler chickens fed organic diets and challenged with Clostridium perfringens.
abstract: Necrotic enteritis (NE) caused by Clostridium perfringens is a reemerging disease of economic importance in areas of the world where antibiotic growth promoters have been banned. The effect of mannan-oligosaccharide (MOS) supplementation in organic diets of broilers challenged with C. perfringens on performance, gut morphology, and innate immunity was investigated. Three hundred Ross-308 broilers were fed antibiotic-free certified organic starter and grower diets. On d 14, birds were orally challenged with 1 mL of C. perfringens culture at 3 × 10(10) cfu/bird. Treatments consisted of a control no-challenge (CO; 0 g/kg of MOS in the basal diet), control challenge (COC, 0 g/kg of MOS in the basal diet), and MOS challenge (2 g/kg of MOS in the basal diet). Challenge of birds resulted in decreased feed intake and BW gain (P = 0.048 and P = 0.026, respectively). Even though supplementation of diet with MOS improved feed intake (P = 0.985), BW gain and G:F were not improved compared with those of the CO group (P = 0.026 and P = <0.001, respectively). There was no significant difference among treatments in jejunal and ileal villus height, crypt depth, and goblet cells/mm(2) (P > 0.05). Quantitative real-time PCR showed that, in the ileum, the MOS diet resulted in an upregulation of toll-like receptor (TLR)2b, TLR4, interleukin (IL)-12p35, and interferon (IFN)-γ compared with CO (P = 0.003, P = 0.018, and P = 0.024, respectively). In the cecal tonsil, challenging birds with C. perfringens resulted in an upregulation of TLR2b compared with CO (P = 0.036), and MOS resulted in an upregulation of TLR4 (P = 0.018). In conclusion, feeding a MOS-supplemented diet to C. perfringens-challenged broiler chickens did not improve performance and gut morphology-associated responses. However, MOS was capable of altering TLR and cytokine profiles, where dual TLR2 and TLR4 pathways were associated with MOS supplementation with subsequent upregulation of ileal IL-12p35 and IFN-γ, implying that MOS supplementation in C. perfringens-challenged chickens supports a proinflammatory effect via T-helper cell-1 associated pathways.
authors.affiliation: Department of Animal Science, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Yitbarek
authors.forename: H
authors.initials: H
authors.lastname: Echeverry
authors.forename: J
authors.initials: J
authors.lastname: Brady
authors.forename: J
authors.initials: J
authors.lastname: Hernandez-Doria
authors.forename: G
authors.initials: G
authors.lastname: Camelo-Jaimes
authors.forename: S
authors.initials: S
authors.lastname: Sharif
authors.forename: W
authors.initials: W
authors.lastname: Guenter
authors.forename: J D
authors.initials: JD
authors.lastname: House
authors.forename: J C
authors.initials: JC
authors.lastname: Rodriguez-Lecompte
mesh_terms: D000821:Animal Feed; D000818:Animals; D001835:Body Weight; D002241:Carbohydrates / Q000737:chemistry / Q000276:immunology*; D002645:Chickens; D003015:Clostridium Infections / Q000276:immunology / Q000662:veterinary*; D003016:Clostridium perfringens; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D004032:Diet / Q000662:veterinary*; D020869:Gene Expression Profiling / Q000662:veterinary; D005786:Gene Expression Regulation; D007113:Immunity, Innate; D011201:Poultry Diseases / Q000276:immunology; D051193:Toll-Like Receptors / Q000235:genetics / Q000378:metabolism; D015003:Yeasts / Q000737:chemistry*
chemical_list: D002241:Carbohydrates; D016207:Cytokines; D051193:Toll-Like Receptors