In Situ Determination of Iron Distribution and Oxidation State in Broiler Duodenal Wall by Synchrotron Radiation μ-XRF and μ-XANES

摘要

Micro-X-ray fluorescence(μ-XRF)and micro-X-ray absorption near edge structure(μ-XANES)have not been widely used in animal nutrition.In situ determination of iron distribution and oxidation state in broiler duodenal wall was done byμ-XRF andμ-XANES techniques.Fifty newly hatched healthy(1-day-old)Arbor Acres commercial male broilers were used in this experiment.The chicks were fed a corn-soybean meal basal diet(96.00 mg of Fe/kg diet)from the 1st day to the 21st day,but were fed a semi-purified diet(12.50 mg of Fe/kg diet)after 21 days to deplete the body Fe stores.On the 28th day,after an overnight fast,all the birds were randomly allotted to four different Fe sources[FeSO4,Fe-Gly(II),FeCl3 and Fe-Gly(Ⅲ)].Three points five mL nutrient solution was injected to a broiler’s duodenum by technology of in situ ligated intestinal loops and a perfusion group without Fe sources added to the media was designed to exclude the effect of endogenous Fe.Being incubated for 30 min,duodenal midpieces sections were collected for analyses byμ-XRF andμ-XANES techniques.It was found that Fe concentration for ferrous Fe sources[FeSO4 and Fe-Gly(Ⅱ)]was significantly higher than that for ferric Fe sources[FeCl3 and Fe-Gly(Ⅲ)]in the duodenal wall,moreover,Fe-Gly(Ⅱ)group samples had the largest amount of Fe.μ-XANES spectra of Fe for the four sources were basically the same in the duodenal wall,which indicated that despite the ferric iron supplied to duodenum,ferrous iron could also be absorbed into the duodenal wall.