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排序方式: 共有347条查询结果,搜索用时 15 毫秒
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The present study was undertaken to compare the effect of salinomycin and Bacillus subtilis on growth performance, serum antibody levels against Clostridium spp. and Eimeria spp., and cytokine mRNA expression levels in broiler chickens raised in the used litter. Broiler chickens fed a diet containing salinomycin showed lower (P < 0.05) body weights compared with the control diet-fed counterparts. Serum nitric oxide levels were significantly (P < 0.05) elevated in chickens fed the B. subtilis-enriched diet compared with those on either the salinomycin-fed or control diet-fed chickens. None of the dietary treatments affected (P > 0.05) serum antibody levels against Clostridium perfringens toxins. Both salinomycin and B. subtilis significantly lowered (P < 0.05) the serum levels of Eimeria-specific antibodies compared with the control group. Salinomycin, but not B. subtilis, significantly modulated (P < 0.05) the expression of cytokines encoding interferon-γ (IFN-γ), interleukin10 (IL-10) and tumor necrosis factor superfamily 15 (TNFSF15) compared with the control group. In conclusion, dietary salinomycin and B. subtilis affected serum anticoccidial antibody and intestinal cytokine expression, but failed to improve growth performance in broiler chickens. Further study is warranted to investigate the mode of action of salinomycin on host immune response and growth performance in broiler chickens. 相似文献
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肠道不仅仅是机体消化、吸收营养物质的主要场所,也是机体的一道防御屏障。肠道黏膜屏障包括黏膜生物屏障、机械屏障、化学屏障和免疫屏障,不论是哪一种肠道黏膜屏障受到损伤,都会导致机体不同程度的伤害,与一些疾病的发生密切相关。本文就肠道黏膜屏障机能及其调控研究进展进行综述,为进一步认识肠道黏膜屏障及治疗由其损伤引起的疾病提供参考和帮助。 相似文献
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用不同保存时间的鸡球虫混合苗,进行了免疫、攻击试验,通过比较免疫组和对照组的死亡率、增重率、血便记分、病变值、卵囊值及抗球虫指数,确定鸡球虫混合苗的保存期应为4℃~8℃、180天。 相似文献
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《动物营养(英文)》2020,6(1):61-68
Effects of supplementing the basal diets with Mn, Zn and Cu, as sulphate, glycine or methionine salts, on colostrum and milk performance, some blood immunity indices and blood minerals of pre- and post-partum Holstein cows were accessed. Forty cows in different groups received: 1) a diet without supplementary Mn, Zn and Cu (control), 2) a diet containing Mn, Zn and Cu sulphates, 3) a diet containing Mn, Zn and Cu glycine, or 4) a diet containing Mn, Zn and Cu methionine with 10 cows per group from d 60 before calving (dry period) to d 100 of lactation. Dry matter intake (DMI), dry matter digestibility (DMD), colostrum and milk performance, milk somatic cell count (SCC), blood and milk total antioxidant capacity (TAC), immunoglobulin M (IgM) and immunoglobulin A (IgA), and blood Mn, Zn and Cu were determined. Dietary supplementation with Mn, Zn and Cu as methionine, glycine or sulphate salts had positive effects on DMD, DMI, colostrum and milk performance, milk SCC, and blood Mn and Zn. Addition of Mn, Zn and Cu in diets could increase (P < 0.05) blood and milk TAC and blood IgA and IgM in the cows and their new-born calves. There were no differences in DMI, DMD, colostrum and milk yields, milk SCC, blood Mn (except d 50 postpartum), Zn and Cu and TAC (except d 50 postpartum) among the organic and inorganic minerals-supplemented groups (P > 0.05), however, the blood concentrations of IgA (except d 1 postpartum) and IgM in the cows supplemented with organic Mn, Zn and Cu were higher (P < 0.05) than those in the cows receiving the sulphate sources of minerals. Overall, dietary supplementation of Mn, Zn and Cu as methionine, glycine or sulphate salts can improve colostrum and milk performance, blood Zn and Mn and immunity indices in Holstein cows and their new-born calves. Moreover, the organic sources of Mn, Zn and Cu have advantage over the sulphate forms in terms of the blood immunoglobulins. 相似文献
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【研究目的】探讨细胞凋亡基因p53在固始鸡免疫器官内的表达及其生理意义;【方法】应用免疫组织化学技术和Leica显微图像处理系统;【结果】p53阳性蛋白表达于法氏囊和胸腺内淋巴细胞细胞膜、细胞质和细胞核。在不同发育阶段固始鸡法氏囊内均有少量p53表达阳性细胞,阳性细胞主要分布于黏膜上皮层与淋巴小结之间靠近上皮层的固有膜内,其次是淋巴小结边缘及淋巴小结与淋巴小结之间的固有膜层内。在1周龄和12周龄固始鸡胸腺内有少量p53表达阳性细胞,阳性细胞主要分布于胸腺小叶皮质与髓质交界处,其次是皮质内,很少出现在髓质内。p53在不同发育阶段固始鸡脾脏内均无表达;【结论】在正常生理情况下,细胞凋亡基因p53参与了固始鸡中枢免疫器官内淋巴细胞发育分化过程中的凋亡调控,对免疫器官的稳定发挥重要作用。 相似文献
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哺乳动物体中的肠道菌群是细菌生态系统的组成部分,从动物出生时起,这些微生物就对免疫系统的发育、功能和调节起着非常重要的作用。当前,越来越多的研究集中在微生物对宿主细胞代谢的影响上。短链脂肪酸(SCFA)作为肠道菌群的一种代谢产物,对肠道稳态的维持具有重要作用。SCFA是肠道上皮细胞的重要燃料,能增强肠屏障功能。作为信号分子,SCFA可以通过细胞表面G蛋白偶联受体(GPCR)发出信号,从而激活控制免疫功能的信号级联反应;还可以通过底物转运蛋白进入细胞,抑制组蛋白脱乙酰化酶(HDAC),最终达到降低肠道炎症反应。本文综述了微生物SCFA的产生及其对肠道黏膜的影响,并通过激活细胞表面GPCR以及抑制组蛋白去乙酰化酶(HDACs)来调节免疫反应的作用。 相似文献
120.
Qinghui Ai Kangsen Mai Beiping Tan Wei Xu Wenbing Zhang Hongming Ma Zhiguo Liufu 《Aquaculture (Amsterdam, Netherlands)》2006,261(1):327-336
An 8 weeks growth experiment was conducted to determine the effects of dietary vitamin C on the survival, growth, tissue ascorbic acid contents and immunity of large yellow croaker (Pseudosciaena crocea) with initial weight of 17.82 ± 0.68 g. Seven practical diets were formulated to contain 0.1, 12.2, 23.8, 47.6, 89.7, 188.5 and 489.0 mg ascorbic acid equivalent kg− 1 diet, supplied as l-ascorbyl-2-polyphosphate (LAPP). Each diet was fed to triplicate groups of fish in seawater floating cages (1.5 × 1.5 × 2.0 m), and each cage was stocked with 120 fish. Fish were fed twice daily (05:00 and 17:00) to apparent satiation for 8 weeks. The water temperature fluctuated from 19.5 to 25.5 °C, the salinity from 25 to 28‰ and dissolved oxygen content was approximately 7 mg l− 1 during the experimental period. Results showed that the specific growth rate (SGR) (from 1.80 to 1.96% d− 1) had an increasing trend with the increase of dietary vitamin C, but no significant difference was observed among dietary treatments. No gross deficiency signs were observed in any of the experimental fish. Survival rate, however, significantly increased with increasing dietary vitamin C (P < 0.05). The vitamin C contents in liver and muscle correlated positively with the vitamin C in diets. The vitamin C requirement was estimated to be 28.2 mg kg− 1 based on survival, and 87.0 mg kg− 1 on liver content of vitamin C. The activities of serum lysozyme and alternative complement pathway (ACP), phagocytosis percentage (PP) and respiratory burst activity of head kidney significantly increased with increasing dietary vitamin C. The challenge experiment with Vibrio harveyi showed that fish fed the diets with supplementation of vitamin C had significantly lower cumulative mortality compared to the control group (66.7%), and the cumulative mortality (16.7%) in fish with 489.0 mg kg− 1 ascorbic acid was significantly lower than that (41.7%) in fish with 23.8 mg kg− 1 ascorbic acid. These results suggested that vitamin C significantly influenced the immune response and disease resistance of large yellow croaker. 相似文献