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Jiao Song Xin Lei Jingxian Luo Nadia Everaert Guiping Zhao Jie Wen Ye Yang 《Journal of animal physiology and animal nutrition》2019,103(4):1030-1038
This study was to investigate the effects of Epigallocatechin‐3‐gallate (EGCG) on intestinal morphology, antioxidant capacity and anti‐inflammatory response in heat‐stressed broiler. A total of 192 2‐week‐old Arbour Acres broilers chickens were divided into four groups with six replicates per group and eight chickens per replicate: one thermoneutral control group (28°C, group TN), which was fed the basal diet; and three cyclic high‐temperature groups (35°C from 7:00 to 19:00 hr; 28°C from 19:00 hr to 7:00 hr, heat stress group), which were fed the basal diet supplementation with EGCG 0 mg/kg (group HS0), 300 mg/kg (group HS300) and 600 mg/kg (group HS600). The gut morphology and intestinal mucosal oxidative stress indicators, as well as intestinal barrier‐related gene expression, were analysed. The results showed that compared with group TN, heat stress reduced the villus height (VH), activities of glutathione peroxidase (GSH‐Px), superoxide dismutase (SOD)and catalase (CAT), increased the crypt depth (CD) and malondialdehyde (MDA)content at 21, 28 and 35 days (p < 0.05). After the heat‐stressed broilers were supplemented with EGCG, VH, VH/CD (V/C), and the activities of GSH‐Px, SOD and CAT were increased, and CD and MDA content were reduced compared with those in group HS0 without EGCG supplementation at 21, 28 and 35 days (p < 0.05). The EGCG supplementation promoted the gene expression of nuclear factor‐erythroid 2‐related factor 2 (Nrf2), Claudin‐1, Mucin 2 (Muc2) and alleviated the nuclear factor‐kappa B (NF‐κB) and lipopolysaccharide‐induced tumour necrosis factor (LITAF) gene expression compared with group HS0 (p < 0.05). Moreover, intestinal morphology was strongly correlated with antioxidant ability and inflammatory response. In conclusion, EGCG alleviated the gut oxidative injury of heat‐stressed broilers by enhancing antioxidant capacity and inhibiting inflammatory response. 相似文献
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在营养液中添加一定量的铵态氮能提高作物生物量和叶绿素含量。为研究增铵对植物生长及叶绿素含量的影响机理,采用了6个NO3-∶NH4 浓度比为5·0∶0·0、5·0∶2·5、5·0∶5·0、5·0∶7·5、5·0∶10·0和0·0∶5·0的处理对小白菜进行培养试验。结果表明,在5mmolL-1硝态氮存在时,适当添加一定量的铵态氮(2·5mmolL-1)小白菜生物量和叶面积分别增加39·6%和16·3%,叶面积与生物量显著相关(r=0·941,p<0·01)。营养液中铵态氮浓度与叶片SPAD值、活性铁及叶绿体蛋白质含量均显著相关,相关系数r分别为0·914、0·954和0·964。适当提高铵态氮浓度增加小白菜产量的机制在于其促进了叶片扩展,提高了总光合面积,其原因可能是适当提高铵态氮浓度促进了叶片细胞分裂。进一步研究表明,提高铵态氮浓度提高叶绿素含量的原因,可能在于其促进了小白菜体内全铁的再利用,从而提高了叶片活性铁含量和叶绿体蛋白质含量。 相似文献
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Response of labile organic C and N pools to plastic film removal from semiarid farmland soil 下载免费PDF全文
S. S. Luo L. Zhu J. L. Liu L. D. Bu S. C. Yue Y. F. Shen S. Q. Li 《Soil Use and Management》2016,32(4):535-542
To examine the effects of plastic film removal on grain yield and soil organic matter (SOM), a spring maize (Zea may L.) field experiment was conducted for 5 yr at Changwu Agricultural and Ecological Experimental Station of Northwest China. Compared with traditional plastic film mulching during entire growing stages (FM), plastic film removal at the silking stage (RM) resulted in a 6.3% higher average maize yield. Under the RM treatment, soil organic carbon and total nitrogen significantly increased after the 5‐yr cultivation in the 0‐ to 20‐cm layer. Significant increases in extractable organic C (EOC), KMnO4‐oxidizable C (KMnO4‐C) and C management index (CMI) in the 0‐ to 20‐cm layer, and light fraction organic C and EOC in the 20‐ to 40‐cm layer were observed in response to plastic film removal after the 1‐yr treatment; the responses were more significant after 5 yr. Under the RM treatment, significant increases in microbial biomass C, light fraction organic N, extractable organic N, KMnO4‐C and CMI were also observed after five years in the 20‐ to 40‐cm layer. Moreover, KMnO4‐C and EOC were much more sensitive than other labile SOM fractions to the application of RM, even after only 1 yr of cultivation. Therefore, compared with mulching for the whole growing season, plastic film removal at the maize silking stage is an effective option for increasing yields and enhancing SOM concentration and soil sustainability in the regions with semiarid monsoon climates that have sufficient rainfall during maize reproductive stages. 相似文献