Agriculture and Agri-Food Canada

About: Agriculture and Agri-Food Canada is a facility organization based out in Ottawa, Ontario, Canada. It is known for research contribution in the topics: Population & Soil water. The organization has 10921 authors who have published 21332 publications receiving 748193 citations. The organization is also known as: Department of Agriculture and Agri-Food.

Methane emissions from feedlot cattle fed barley or corn diets.

Abstract: Methane emitted from the livestock sector contributes to greenhouse gas emissions worldwide Understanding the variability in enteric methane production related to diet is essential to decreasing uncertainty in greenhouse gas emission inventories and to identifying viable greenhouse gas reduction strategies Our study focused on measuring methane in growing beef cattle fed corn- or barley-based diets typical of those fed to cattle in North American feedlots The experiment was designed as a randomized complete block (group) design with two treatments, barley and corn Angus heifer calves (initial BW = 328 kg) were allocated to two groups (eight per group), with four cattle in each group fed a corn or barley diet The experiment was conducted over a 42-d backgrounding phase, a 35-d transition phase and a 32-d finishing phase Backgrounding diets consisted of 70% barley silage or corn silage and 30% concentrate containing steam-rolled barley or dry-rolled corn (DM basis) Finishing diets consisted of 9% barley silage and 91% concentrate containing barley or corn (DM basis) All diets contained monensin (33 mg/kg of DM) Cattle were placed into four large environmental chambers (two heifers per chamber) during each phase to measure enteric methane production for 3 d During the backgrounding phase, DMI was greater by cattle fed corn than for those fed barley (102 vs 76 kg/d, P < 001), but during the finishing phase, DMI was similar for both diets (83 kg/d) The DMI was decreased to 63 kg/d with no effect of diet or phase while the cattle were in the chambers; thus, methane emissions (g/d) reported may underestimate those of the feedlot industry Methane emissions per kilogram of DMI and as a percentage of GE intake were not affected by grain source during the backgrounding phase (246 g/kg of DMI; 742% of GE), but were less (P < 005) for corn than for barley during the finishing phase (92 vs 131 g/kg of DMI; 281 vs 403% of GE) The results indicate the need to implement dietary strategies to decrease methane emissions of cattle fed high-forage backgrounding diets and barley-based finishing diets Mitigating methane losses from cattle will have long-term environmental benefits by decreasing agriculture's contribution to greenhouse gas emissions

Which polyphenolic compounds contribute to the total antioxidant activities of apple

Abstract: The antioxidant activities of eight apple cultivars were studied by using the ferric reducing/antioxidant power (FRAP), the beta-carotene-linoleic acid model system (beta-CLAMS), and the photochemiluminescent (PCL) assays. The antioxidant activity of apples is highly correlated to the total phenolic content (TPC) measured by the Folin-Ciocalteu method and the total polyphenolic index (TPI) obtained by HPLC. Extracts of the peel and flesh were analyzed and assayed separately. The FRAP activities of both peel and flesh extracts correlate well with the TPC (r = 0.95 and 0.99, respectively) and the TPI (r = 0.82 and 0.99, respectively). Similar results were found in the beta-CLAMS activities, showing correlation coefficients of r = 0.90 and 0.91 with the TPC for the peel and flesh extracts and of r = 0.90 and 0.84 with the TPI for the peel and flesh extracts, respectively. The antioxidant activity measured by the PCL assay was not correlated with TPC or TPI due to the lack of integratable lag phase in this method with the flavan-3-ols/procyanidins. Among the five major polyphenolic groups, flavan-3-ols/procyanidins had the highest positive correlation with the FRAP and beta-CLAMS activities: r = 0.84 and 0.88 for the peel extracts, respectively; and r = 0.98 and 0.87 for the flesh extracts, respectively. At individual compound level, epicatechin and procyanidin B2 were the major contributors to the antioxidant activity of apple. Hydroxycinnamic acids may have a significant role in the flesh.