title: Nutritional and metabolic implications of replacing cornstarch with D-xylose in broiler chickens fed corn and soybean meal-based diet.
abstract: Effects of substituting cornstarch with D-xylose on growth performance, nutrients digestibility, serum metabolites, and expression of select hepatic genes involved in glucose and lipid metabolism were investigated in broiler chickens. A total of 360 one-day-old male Ross chicks were fed 3 diets (n = 24; 5 chicks/cage) for 21 days. A control corn-soybean meal-based diet with 25% cornstarch was formulated to meet specifications. Two additional diets were formulated by substituting cornstarch with 5 or 15% D-xylose w/w. Growth performance and digestibility by index method were determined in 12 replicate cages. Birds in these replicates had free access to feed and water, the BW and feed intake (FI) were monitored weekly and the excreta samples were collected on d 18 to 20. The other 12 replicates were used for blood and liver sampling by serial slaughter. On d 18, baseline (t0) birds were sampled following a 12 h overnight fasting and birds allowed 30 min access to the feed; samples were subsequently taken at 60, 120, 180, 240, and 300 min post feeding. Serum metabolites (glucose, xylose, and insulin) were assayed at all time points, whereas expression of hepatic transcripts was evaluated at zero, 180 and 300 min. Xylose linearly reduced (P < 0.05) FI, BWG, gross energy digestibility, and feed conversion ratio (FCR) but increased (P < 0.05) serum xylose level. Serum glucose and insulin levels were higher (P < 0.05) in the post-fed state compared with baseline, irrespective of treatments. There was an interaction (P < 0.05) between diet and sampling time on the expression of hepatic genes. At t0, xylose linearly increased (P < 0.05) the expression of pyruvate carboxylase, Acetyl Co-A acethyltransferase 2 (ACAT2), and glucose transporter 2. Xylose linearly reduced (P < 0.05) the expression of ACAT2 at 300 min post feeding. In conclusion, 5% or more xylose reduced growth performance and utilization of nutrients linked to hepatic enzymes and transcription factors involved in glucose and lipid metabolism.
authors.affiliation: Department of Animal Science, University of Manitoba, Winnipeg, MB, Canada R3T 2N2.
authors.forename: A
authors.initials: A
authors.lastname: Regassa
authors.affiliation: Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1 ekiarie@uoguelph.ca.
authors.forename: E
authors.initials: E
authors.lastname: Kiarie
authors.affiliation: Department of Animal Science, University of Manitoba, Winnipeg, MB, Canada R3T 2N2.
authors.forename: J S
authors.initials: JS
authors.lastname: Sands
authors.affiliation: DuPont Industrial Biosciences-Danisco Animal Nutrition, Marlborough, United Kingdom SN8 1XN.
authors.forename: M C
authors.initials: MC
authors.lastname: Walsh
authors.affiliation: Department of Poultry Science, University of Georgia, Athens, GA 30602.
authors.forename: W K
authors.initials: WK
authors.lastname: Kim
authors.affiliation: Department of Animal Science, University of Manitoba, Winnipeg, MB, Canada R3T 2N2.
authors.forename: C M
authors.initials: CM
authors.lastname: Nyachoti
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena / Q000187:drug effects; D000818:Animals; D030161:Avian Proteins / Q000235:genetics* / Q000378:metabolism; D001774:Blood Chemical Analysis / Q000662:veterinary; D002645:Chickens / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D004032:Diet / Q000662:veterinary; D005947:Glucose / Q000378:metabolism*; D050356:Lipid Metabolism; D008099:Liver / Q000201:enzymology / Q000378:metabolism; D008297:Male; D011897:Random Allocation; D013213:Starch / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014994:Xylose / Q000378:metabolism*
chemical_list: D030161:Avian Proteins; D014157:Transcription Factors; D013213:Starch; D014994:Xylose; D005947:Glucose
keywords: D-xylose; broilers; glucose and lipid metabolism; growth and nutrients utilization