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41.
This experiment was conducted to evaluate the effect of zinc, manganese, and copper sources (inorganic vs. organic) in the diet on laying performance and eggshell quality characteristics. One hundred and eighty Hy-Line W-36 layers at 38 weeks of age were allocated to 36-layer cages of five hens each. Each six cages were randomly assigned to one of the six experimental diets fed from 38 to 53 week of age. In three experimental treatments, the basal diet was supplemented with 65–75–7 or 65–75–7 or 40–40–7 mg/kg of Zn, Mn, and Cu, respectively, from their oxide or sulfate sources. Three other groups were fed diets supplemented with 20–20–3.5 or 40–40–7.5 or 60–60–10.5 mg/kg of organic forms of Zn, Mn, and Cu, respectively. Dietary treatments significantly did affect feed intake (P < 0.001), feed conversion ratio (P < 0.001) and percentage of broken eggs (P < 0.05). Substitution of Zn and Mn oxides (65 and 75 mg kg−1, respectively) with equal amounts of their sulfate forms significantly improved feed intake, feed conversion ratio, percentage of broken eggs, and Haugh Unit (P < 0.05). In addition, laying hens maintained their performance when substitution of Zn and Mn oxides and Cu sulfate (65, 75, and 7 mg kg−1, respectively) reduced up to 20, 20, and 3.5 mg kg−1 by amino acid complexes of the microelements. The results showed that a corn–soybean diet supplemented with the organic forms of Zn, Mn, and Cu at a dosage 50% to 75% lower than NRC recommendation is sufficient to maintain laying performance and can improve eggshell and albumen qualities of the egg in laying hens.  相似文献   
42.
Aereal parts of three Asteraceae from Iran have been analysed for exudate flavonoids. Artemisia oliveriana, Pulicaria gnaphalodes and Tanacetum polycephalum are shown to accumulate mostly 6-methoxylated flavonols and flavones as external aglycones.  相似文献   
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Evaluation of metabolic pathways is one of the challenging areas in biological and pharmaceutical sciences. Phenanthridine oxidation to phenanthridinone is used commonly to study aldehyde oxidase activity. This reaction could pass through phenanthridine N-oxide intermediate. In the present study, the application of multivariate curve resolution, optimized by alternating least squares (MCR-ALS) to investigate this metabolic pathway has been described. The results obtained from MCR-ALS analysis along with those obtained from the use of potassium ferrocyanide method indicated that phenanthridine is directly oxidized to phenanthridinone by rat liver aldehyde oxidase without passing through phenanthridine N-oxide intermediate. It was also found that the later compound is not metabolized by this enzyme.  相似文献   
45.
This paper aimed to study Lower Miocene (Burdigalian) mixed carbonate–siliciclastic deposits within an Upper Cenozoic synorogenic conglomerate–dominated succession in north of Shalamzar in the Zagros foreland basin, Iran. The deposits are composed of nine facies: foraminiferal mudstone, silty mudstone, sandy mudstone, fossiliferous sandy mudstone, fossiliferous argillaceous mudstone, fossiliferous calclithite, coral limestone, calcareous claystone and hybrid sandstone. The facies represent a mixed carbonate– siliciclastic shelf–type fan–delta. The subenvironments of the fan–delta include muddy pro–delta, sandy delta– front, clastic proximal mouth bar and a subordinate delta plain. Siliciclastic input and sedimentation rate controlled the paleoecological distribution of different benthic carbonate–producing fauna in the fan–delta during its progradation into a shelf marine environment. Input of siliciclastic deposits and sedimentation rate limited the diversity and development of corals and controlled their colonization and growth morphologies in the sandy delta–front. Siliciclastic input (including plant materials and coal debris) and sedimentation rate controlled the trophic habitats of many gastropods and their abundance and distribution in the sandy delta– front and clastic proximal mouth bar. Also, increased siliciclastic input favored abundance of larger benthic foraminifera in most parts of the fan–delta with the exception of the muddy pro–delta.  相似文献   
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