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91.
Heat stress(HS)can be detrimental to the gut health of swine.Many negative outcomes induced by HS are increasingly recognized as including modulation of intestinal microbiota.In turn,the intestinal microbiota is a unique ecosystem playing a critical role in mediating the host stress response.Therefore,we aimed to characterize gut microbiota of pigs’exposure to short-term HS,to explore a possible link between the intestinal microbiota and HS-related changes,including serum cytokines,oxidation status,and intestinal epithelial barrier function.Our findings showed that HS led to intestinal morphological and integrity changes(villus height,serum diamine oxidase[DAO],serum D-lactate and the relative expressions of tight junction proteins),reduction of serum cytokines(interleukin[IL]-8,IL-12,interferongamma[IFN-g]),and antioxidant activity(higher glutathione[GSH]and malondialdehyde[MDA]content,and lower superoxide dismutase[SOD]).Also,16S rRNA sequencing analysis revealed that although there was no difference in microbial a-diversity,some HS-associated composition differences were revealed in the ileum and cecum,which partly led to an imbalance in the production of short-chain fatty acids including propionate acid and valerate acid.Relevance networks revealed that HS-derived changes in bacterial genera and microbial metabolites,such as Chlamydia,Lactobacillus,Succinivibrio,Bifidobacterium,Lachnoclostridium,and propionic acid,were correlated with oxidative stress,intestinal barrier dysfunction,and inflammation in pigs.Collectively,our observations suggest that intestinal damage induced by HS is probably partly related to the gut microbiota dysbiosis,though the underlying mechanism remains to be fully elucidated. 相似文献
92.
Nguyen Thanh Vu Tran Huu Phuc Nguyen Trung Ky Nguyen Thi Kieu Nga Nguyen Hong Nguyen 《Aquaculture Research》2020,51(4):1381-1387
Sexual dimorphism is widely observed in almost all farmed aquatic animal species but giant freshwater pawn (GFP) is unique, with males characterized by three main morphotypes (blue claw, orange claw and small males) and females by different reproduction status (ovary, berried egg and already‐spawned females). There has been reported evidence that the effect of male morphotype may have masked genetic variation in growth‐related traits, as a result the heritability for male body weight was lower than that estimated in female. A pending question has arisen whether selection should be made in female only. To answer this question, we used an 8‐year data set from a long‐term selection programme (2008–2015) for high growth in this species comprising 106,756 individuals that were offspring of 515 sires and 810 dams. The body weight data of female and male GFP or of each morphotype was treated as a separate trait and a multi‐trait approach was used to estimate genetic correlations for homologous traits between sexes and between morphotypes. Our analysis showed that there were little differences in the heritability estimates between female and male. In female, mature ovary individual displayed higher heritability than berried egg and already‐spawned females. For male, the heritability for blue claw, orange claw and small males were 0.11, 0.06 and 0.00 respectively. Between‐sex genetic correlation was moderate (0.55 ± 0.11) for body weight, suggesting that the trait expressions in female and male may be genetically different. In female, the genetic correlations for body weight among three female types were close to one (0.91–0.94). In contrast, the genetic correlations for body weight between male morphotypes especially between blue claw or orange claw and small males were low (0.15–0.25). Furthermore, we estimated genetic gain as the difference in least square means (LSM) or estimated breeding values (EBV) between the selection line and control group. The genetic gain in body weight was smaller in females than in males. It is concluded that there is no need to run separate breeding programme for female and male GFP. A combined selection using both female and male data can achieve selection response for body weight as demonstrated in the present study. 相似文献
93.
94.
通过对青岛市地区范围内农村的问卷调查,对新型农村社会交往的影响因素进行了分析。结果表明,农民的行业选择、信息采用、投资意识及收入增加等都极大地推动了农民社会交往的发展。 相似文献
95.
AIM: To identify the potential proteins interacting with NR2D subunit of NMDA receptor by yeast two-hybrid screening and to investigate the role of NR2D in excitotoxicity of the retina.METHODS: The Clontech GAL4 yeast two-hybrid system was used to screen the mouse brain cDNA library, and the bait plasmid containing C-terminus of NR2D was constructed. Physical interaction between 2 proteins was verified by co-immunoprecipitation assay. The subcellular localization of 2 proteins in the mouse retina was observed under microscope with immunofluorescence.RESULTS: Modifier of cell adhesion (MOCA) was identified as a new protein interacting with NR2D. MOCA and NR2D were co-expressed in the mouse retina. CONCLUSION: MOCA specifically interacts with NR2D, which provides the experimental basis for identifying the role of glutamate excitotoxicity in the retina neurodegeneration. 相似文献
96.
为研究小型猪专用复合麻醉剂(XFM)及其特异性颉颃剂交互应用对大鼠不同脑区iNOS mRNA转录的影响,将48只SD大鼠随机分为生理盐水对照组(C)和XFM与颉颃剂交互作用组(MJ),MJ组分为早期交互(MJ1、MJ2)和晚期交互(MJ3、MJ4)2个亚组。各组大鼠到达预定时间点后分别采取脑组织,应用实时荧光定量PCR技术检测各组织中iNOS mRNA表达量。结果显示,XFM及其特异性颉颃剂交互应用时,大脑、小脑、海马、脑干和丘脑中iNOS mRNA转录均受到显著抑制(P〈0.01),虽能逐渐回升,但在试验选取时间点内只有小脑与海马中iNOS mRNA转录恢复正常。结果表明,XFM及其特异性颉颃剂在交互作用时能够显著抑制中枢神经系统中iNOS mRNA的转录,部分脑区可以完全恢复,这可能与XFM及其特异性颉颃剂交互作用机制有关。 相似文献
97.
The Ecological Concept of Costs of Induced Systemic Resistance (ISR) 总被引:11,自引:0,他引:11
Martin Heil 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(1):137-146
Plant defence is thought to provide benefits for the defended plants. Theoretical concepts must, therefore, explain why there is variation in defensive traits, which naively might be assumed to be present constitutively in fixed high amounts. Explanations are mainly based on the assumption of fitness costs. Investment in defence is thought to reduce the fitness of plants in enemy-free environments. Fitness costs often result from allocation costs, i.e. allocation of limited resources to defence, which then cannot be used for growth or other fitness-relevant processes. This theoretical concept can provide a useful tool for the interpretation of induced plant responses against pathogens, named induced systemic (or systemic acquired) resistance (ISR or SAR). Phenotypic plasticity, leading to induced responses, might have evolved mainly to reduce costs, since investment in defence is restricted to situations actually requiring defence. ISR can incur allocation costs and other, indirect costs, which ultimately may lead to fitness costs. Evolution of any defensive trait depends on both what a plant ideally 'should do and what it actually 'is able to do. Costs of defence constrain its expression. This might have important influences on the evolution of plant defensive traits, as well as on the exploitation of natural defences in agricultural crop protection. 相似文献
98.
99.
Evaluation and analysis of reduction of late blight disease in a diploid potato progeny 总被引:2,自引:0,他引:2
B. R. Trognitz † M. Orrillo L. Portal C. Román P. Ramón S. Perez G. Chacón 《Plant pathology》2001,50(3):281-291
The rate of late blight disease was analysed for individuals of a diploid Solanum phureja – Solanum tuberosum dihaploid hybrid population (PD), using three different assessment techniques, in the laboratory, screenhouse, and field. These hybrids expressed low disease rates in the field, comparable to resistance based on intact R genes. However, none of the parents of PD expressed any R genes and the pattern of segregation within the PD population was not indicative of R-gene inheritance. The foliage (or leaflet) area diseased had the largest broad-sense heritability of all criteria analysed, in all tests performed. In the field evaluations, the PD population showed intermediate levels of broad-sense heritability for foliage area diseased, relative to the much larger heritability detected for the group of controls possessing R genes. Resistance in the field of the PD hybrids had very little genotype-environment (G × E) interaction, indicating stability of its expression. All genotypes without R genes exhibited heritable, reduced rates of late blight disease in the field, but they were susceptible with low heritability in screenhouse and laboratory tests. This differential expression of disease indicates that the plants' indirect response to unknown environmental stress in the field may have been measured. The value of the PD hybrids for breeding of late blight resistant potato and the use of the disease rate data for detection of the underlying quantitative trait loci are discussed. 相似文献
100.