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Wheat is the primary grain fed to poultry in western Canada, but its nutritional quality, including the nature of its starch digestibility, may be affected by wheat market class. The objectives of this study were to determine the rate and extent of starch digestibility of wheat market classes in broiler chickens, and to determine the relationship between starch digestibility and wheat apparent metabolizable energy (AME). In vitro starch digestion was assessed using gastric and small intestinal phases mimicking the chicken digestive tract, while in vivo evaluation used 468 male broiler chickens randomly assigned to dietary treatments from 0 to 21 d of age. The study evaluated 2 wheat cultivars from each of 6 western Canadian wheat classes: Canadian Prairie Spring (CPS), Canadian Western Amber Durum (CWAD), CW General Purpose (CWGP), CW Hard White Spring (CWHWS), CW Red Spring (CWRS), and CW Soft White Spring (CWSWS). All samples were analyzed for relevant grain characteristics. Data were analyzed as a randomized complete block design and cultivars were nested within market class. Pearson correlation was used to determine relationships between measured characteristics. Significance level was P ≤ 0.05. The starch digestibility range and wheat class rankings were: proximal jejunum - 23.7 to 50.6% (CWHWSc, CPSbc, CWSWSbc, CWRSab, CWGPa, CWADa); distal jejunum - 63.5 to 76.4% (CWHWSc, CPSbc, CWSWSbc, CWRSab, CWGPa, CWADa); proximal ileum - 88.7 to 96.9% (CWSWSc, CPSbc, CWHWSbc, CWRSb, CWGPb, CWADa); distal ileum - 94.4 to 98.5% (CWSWSb, CWHWSb, CPSb, CWRSab, CWGPab, CWADa); excreta - 98.4 to 99.3% (CPSb, CWRSb, CWHWSb, CWSWSab, CWGPab, CWADa). Wheat class affected wheat AMEn with levels ranging from 3,203 to 3,411 kcal/kg at 90% DM (CWRSc, CWSWSc, CPSb, CWGPb, CWADa, CWHWSa). Significant and moderately strong positive correlations were observed between in vitro and in vivo starch digestibility, but no correlations were found between AME and starch digestibility. In conclusion, rate and extent of starch digestibility and AME were affected by western Canadian wheat class, but starch digestibility did not predict AME.

To understand raffinose family oligosaccharides (RFO) metabolism in chickpea (Cicer arietinum L.) seeds, RFO accumulation and corresponding biosynthetic enzymes activities were determined during seed development of chickpea genotypes with contrasting RFO concentrations. RFO concentration in mature seeds was found as a facilitator rather than a regulating step of seed germination. In mature seeds, raffinose concentrations ranged from 0.38 to 0.68 and 0.75 to 0.99 g/100 g, whereas stachyose concentrations varied from 0.79 to 1.26 and 1.70 to 1.87 g/100 g indicating significant differences between low and high RFO genotypes, respectively. Chickpea genotypes with high RFO concentration accumulated higher concentrations of myo-inositol and sucrose during early seed developmental stages suggesting that initial substrate concentrations may influence RFO concentration in mature seeds. High RFO genotypes showed about two to three-fold higher activity for all RFO biosynthetic enzymes compared to those with low RFO concentrations. RFO biosynthetic enzymes activities correspond with accumulation of individual RFO during seed development., (Copyright © 2016 Elsevier Ltd. All rights reserved.)