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Essential oils are widely used in the pharmaceutical, food and cosmetic industries, and many plant essential oils have shown that they have positive effects on broilers nutrition. This experiment was conducted to study the effects of orally administered different dosages of carvacrol essential oils on intestinal barrier function in broiler chickens. A total of eighty 28‐day‐old (1.28 ± 0.15 kg) ROSS 308 broilers were randomly allocated to four groups of 20 replicates each, with one chicken per replicate per cage, and all were fed with the same diet. Four experimental groups were orally administered 0, 200, 300 or 400 μl carvacrol essential oils at 18:00 hr every day during the 2‐week experimental period. As a result of which, the gene expression of the occludin, claudin‐1, claudin‐5, ZO‐1 and ZO‐2 in intestinal mucosa of small intestine (p < 0.05) and the goblet cell content in small intestine epithelium (p < 0.05) were significantly increased; test subjects with 300 or 400 μl carvacrol essential oils reduced the microbial counts of Salmonella spp. and Escherichia coli in the intestines (p < 0.05); Essential oils administration also significantly increased activity of the sucrase (p < 0.05) and lactase (p < 0.05) in intestinal mucosa. In conclusion, the carvacrol essential oils have positive effects on growth performance and intestinal barriers function of broilers; those effects may be related to the dosage, as administration of 300 or 400 μl was more effective than that of 200 μl.  相似文献   
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Male hybrids from a cross between female mice of strain C57BL/6Kh and males of strain DBA/2J lived longer after injection of P815 mastocytoma cells of DBA/2 origin than did their female siblings. Responses to the histocompatibility antigen on the X chromosome of the DBA/2 strain may be involved in resistance to the tumor. When the female parent was replaced with a C57BL/6Kh carrying one of several mutations in the H-2 region, this sex effect disappeared in some of the hybrid combinations. Thus, the H-2 complex appears to be involved in the regulation of the immune response to the X-linked histocompatibility antigen in this tumor model.  相似文献   
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Using two drought resistant wheat (Triticum aestivum L.) cultivars, ‘Changwu134’ and ‘Changhan58,’ a field experiment was conducted in ChangWu Agro-ecological Experiment Station on China's Loess Plateau during 2008 and 2009 to compare the effects of different fertilizer and tillage treatments on the fructan contents as well as fructan exo-hydrolase (FEH) activity in relation to wheat yield. We found that ‘Changhan58’ had greater yield and fructan content in the penultimate internode and higher FEH activity than did ‘Changwu134.’ For ‘Changhan58.’ applying 195 kg·ha?1(120 +75) N plus 45000 kg·ha?1 of pig manure and 120 kg·ha?1 phosphate under conservation tillage produced the highest yield (6769 ka/ha), fructan content in penultimate internode, water use efficiency (WUE), as well as FEH activity among the fertilizer and tillage treatments. Therefore, routine soil management for wheat should focus on combined use of manures and inorganic fertilizer to enhance the amount and transportation efficiency of WSC and ultimately ensure greater yield.  相似文献   
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Background:Gut is a crucial organ for the host’s defense system due to its filtering action of the intestinal membrane from hazardous foreign substances.One strategy to strengthen the gut epithelial barrier function is to upregulate beneficial microflora populations and their metabolites.Sophorolipid(SPL),which is a glycolipid biosurfactant,could increase beneficial microflora and decrease pathogenic bacteria in the gastrointestinal tract.Therefore,herein,we conducted an experiment with broiler chickens to investigate the fortifying effects of SPL on the host’s gut defense system by modulating the microbiota population.Methods:A total of 5401-day-old chicks(Ross 308)were used,and they were immediately allotted into three treatment groups(6 replications with 30 chicks/pen)according to their initial body weight.The dietary treatments consisted of CON(basal diet),BAM(10 mg/kg bambermycin),and SPL(10 mg/kg SPL).During the experiment,birds freely accessed feed and water,and body weight and feed intake were measured at the end of each phase.On d 35,birds(one bird/pen)were sacrificed to collect jejunum and cecum samples.Results:Dietary SPL and BAM supplementation significantly accelerated birds’growth and also significantly improved feed efficiency compared to CON.Intestinal microbial community was significantly separated by dietary SPL supplementation from that of CON,and dietary SPL supplementation significantly increased Lactobacillus spp.and Akkermansia muciniphila.Moreover,birds fed with dietary SPL also showed the highest concentration of cecal butyrate among all treatment groups.Gut morphological analysis showed that dietary SPL significantly increased villus height,ratio of villus height to crypt depth,goblet cell numbers,and the gene expression levels of claudin-1 and mucin 2.Additionally,dietary SPL significantly decreased the mRNA expression level of pro-inflammatory cytokine,interleukin-6,and increased that of anti-inflammatory cytokine,interleukin-10,compared to other treatments.Conclusions:Dietary SPL increases the beneficial bacterial population and butyrate concentration,which leads to a strengthened gut barrier function.In addition,the intestinal inflammation was also downregulated by dietary SPL supplementation.  相似文献   
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Since the discovery of penicillin in 1928 and throughout the ‘age of antibiotics’ from the 1940s until the 1980s, the detection of novel antibiotics was restricted by lack of knowledge about the distribution and ecology of antibiotic producers in nature. The discovery that a phenazine compound produced by Pseudomonas bacteria could suppress soilborne plant pathogens, and its recovery from rhizosphere soil in 1990, provided the first incontrovertible evidence that natural metabolites could control plant pathogens in the environment and opened a new era in biological control by root‐associated rhizobacteria. More recently, the advent of genomics, the availability of highly sensitive bioanalytical instrumentation, and the discovery of protective endophytes have accelerated progress toward overcoming many of the impediments that until now have limited the exploitation of beneficial plant‐associated microbes to enhance agricultural sustainability. Here, we present key developments that have established the importance of these microbes in the control of pathogens, discuss concepts resulting from the exploration of classical model systems, and highlight advances emerging from ongoing investigations. © 2019 Society of Chemical Industry  相似文献   
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Objective— To investigate the development of gingival hyperplasia in dogs after renal transplantation and administration of microemulsified cyclosporine A (MCsA).
Study Design— Experimental study.
Animals— Healthy adult mongrel dogs (n=5).
Methods— As part of study on renal transplantation, dogs administered MCsA (20 mg/kg/day), azathioprine, and prednisolone to prevent graft rejection were monitored for development of gingival changes. Prednisolone was discontinued after 3 months. MCsA dose was adjusted to maintain whole blood trough concentration of 400–700 ng/mL. Gingival change was evaluated by weekly examination and photodocumentation, and gingival biopsy for histopathology was performed at 28 weeks.
Results— One dog was lost because of acute graft rejection. Gingival hyperplasia developed in 3 of 4 dogs. The earliest gingival changes occurred in the interdental papillae at 20 weeks after transplantation. On histopathology, the underlying connective tissue was thickened and contained increase numbers of fibroblasts and inflammatory infiltrates.
Conclusions— Long-term immunosuppression with an MCsA-based treatment likely induces substantial gingival hyperplasia when therapeutic, immunosuppressive blood levels of MCsA were maintained for 32 weeks.
Clinical Relevance— MCsA is used for immune-mediated diseases and preventing rejection after transplant in dogs. MCsA blood levels, and gingival hyperplasia should be monitored by routine examination of the interdental papilla in dogs administered MCsA for long periods.  相似文献   
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