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抗热应激中草药添加剂的研究进展 总被引：21，自引：1，他引：20
高温是影响畜禽生产的重要因素。热应激使畜禽生产效率下降，饲料利用率降低，发病率及死亡率升高，给畜禽生产造成了一定的经济损失，已引起国内外畜牧工作者的广泛关注。因此，近年来人们进行了大量的抗热应激添加剂的研究。但由于对热应激机理尚不清楚，人们只能根据畜... 相似文献
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热应激是影响畜禽生产的重要因素之一，可导致畜禽采食量减少，生长速度下降，免疫机能抑制，发病率增高：同时还导致肌肉系水力下降，寿命缩短等诸多问题。我国畜牧生产主要基地大部分位于暖温带和亚热带，夏季日平均气温普遍高于27．5℃（中国统计年鉴，2006）。热应激引起的疾病和畜禽生长缓慢造成了巨大的经济损失，已引起国内外畜牧工作者的广泛关注。随着对热应激产生机理和热应激蛋白的深入研究，人们进行了大量抗热应激添加剂的试验研究。人们根据畜禽在热应激时的表现及血液生化指标的变化对症下药，筛选出一些具有抗热应激作用的解热镇静剂、电解质、维生素、抗生素以及一些微量元素。 相似文献
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随着全球气候变暖，夏季高温环境下热应激严重影响畜禽健康，降低畜禽生产效率和产品品质，给养殖业造成了极大的经济损失。色氨酸属于芳香族氨基酸，是畜禽的必需氨基酸，同时也是多种生物活性分子的前体物质，可以调节机体肠道屏障和免疫功能，降低动物的应激反应。本文就热应激对畜禽肠道屏障及免疫功能的影响和色氨酸代谢对肠道屏障及免疫功能的调控作用进行综述，并探讨了色氨酸及其代谢产物调控热应激条件下畜禽肠道屏障及免疫功能的作用机制，以期为生产中应用色氨酸缓解畜禽热应激提供参考。 相似文献
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热应激蛋白（HSPs）是机体在应激条件下产生的一类高度保守的蛋白质分子家族,对畜禽抗应激机理有着重要的作用,本文简要介绍了热应激蛋白的分类,以及HSP70、HSP90和小分子质量HSPs家族的基因结构、功能及在热应激条件下的表达,为畜禽生产中的抗应激机理研究提供理论参考。 相似文献
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Heat stress is a very universal stress event in recent years. Various lines of evidence in the past literatures indicate that gut microbiota composition is susceptible to variable temperature. A varied microbiota is necessary for optimal regulation of host signaling pathways and disrupting microbiota-host homeostasis that induces disease pathology. The microbiota–gut–brain axis involves an interactive mode of communication between the microbes colonizing the gut and brain function. This review summarizes the effects of heat stress on intestinal function and microbiota–gut–brain axis. Heat stress negatively affects intestinal immunity and barrier functions. Microbiota-gut-brain axis is involved in the homeostasis of the gut microbiota, at the same time, heat stress affects the metabolites of microbiota which could alter the function of microbiota–gut–brain axis. We aim to bridge the evidence that the microbiota is adapted to survive and thrive in an extreme environment. Additionally, nutritional strategies for alleviating intestinal heat stress are introduced. 相似文献
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热应激影响荷斯坦奶牛泌乳机制的研究进展 总被引：1，自引：0，他引：1
《中国畜牧杂志》2019,(3)
奶牛在极端热环境下会产生热应激反应,导致奶牛泌乳量降低、乳品质下降。本文从热应激诱导乳腺氧化应激及影响机体激素代谢、抑制乳成分合成角度综述了热应激影响奶牛泌乳的机制,并对补饲添加剂缓解热应激的效果进行总结,以期为进一步探究热应激机理及寻求有效、合理的缓解措施提供理论依据。 相似文献
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Exposure to high temperatures during the summer renders pigs susceptible to severe heat stress. Our previous studies found that pig small intestine epithelial tissue became significantly damaged following exposure to heat stress, negatively affecting body weight gain. The deleterious effects of heat stress could be ameliorated using a traditional Chinese medicine decoction (CMD), sustaining normal growth while under heat stress. In the current study, we hypothesized the mechanism of CMD activity to be via regulation of gut hormones (NPY, MLN, SCT and GCG) secretion from endocrine cells, which are responsible for nutrient digestion and absorption. To test this, 36 Chinese experimental mini-pigs (2 months of age) were screened according to weight and litter origin, and divided into three treatment groups: control (23 °C for 24 h + standard feed), heat stress (HS; 26 °C for 19 h, 40 °C for 5 h + standard feed) and CMD (26 °C for 19 h, 40 °C for 5 h + standard feed supplemented with CMD); n = 12 per group. Feed intake and body weight gain were measured daily. Pigs were euthanized at days 1 and 6 after initial treatment with blood and sections of small intestine epithelial tissue collected. Serum cortisol (Cor) concentrations were determined using RIA. Endocrine cell number and structural analysis were performed using silver staining, and gut hormone secretion examined by microarray. Dietary supplementation with CMD significantly improved porcine growth performance (P < 0.05), decreased the Cor levels (P < 0.01), increased endocrine cell number as well as up-regulating neuropeptide Y (NPY), motilin (MLN) and secretin (SCT) and down-regulating glucagon (GCG) expression in pig jejunum on day 6 when compared with the HS group. Taken together, our results indicate CMD supplementation can significantly reduce the negative effects of heat stress on pig jejunum, maintaining growth performance similar to non-heat stressed animals. CMD's activity appears to be via adjusting gut hormone secretion to regulate metabolism and improve animal growth. 相似文献
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《畜牧与生物技术杂志(英文版)》2018,(4)
Background: Understanding the composition of the microbial community and its functional capacity during weaning is important for pig production as bacteria play important roles in the pig's health and growth performance. However,limited information is available regarding the composition and function of the gut microbiome of piglets in early-life.Therefore, we performed 16 S rRNA gene and whole metagenome shotgun sequencing of DNA from fecal samples from healthy piglets during weaning to measure microbiome shifts, and to identify the potential contribution of the early-life microbiota in shaping piglet health with a focus on microbial stress responses, carbohydrate and amino acid metabolism.Results: The analysis of 16 S rR NA genes and whole metagenome shotgun sequencing revealed significant compositional and functional differences between the fecal microbiome in nursing and weaned piglets. The fecal microbiome of the nursing piglets showed higher relative abundance of bacteria in the genus Bacteroides with abundant gene families related to the utilization of lactose and galactose. Prevotel a and Lactobacil us were enriched in weaned piglets with an enrichment for the gene families associated with carbohydrate and amino acid metabolism. In addition, an analysis of the functional capacity of the fecal microbiome showed higher abundances of genes associated with heat shock and oxidative stress in the metagenome of weaned piglets compared to nursing piglets.Conclusions: Overal, our data show that microbial shifts and changes in functional capacities of the piglet fecal microbiome resulted in potential reductions in the effects of stress, including dietary changes that occur during weaning.These results provide us with new insights into the piglet gut microbiome that contributes to the growth of the animal. 相似文献
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Gut microbiota is generally recognized to play a crucial role in maintaining host health and metabolism. The correlation among gut microbiota, glycolipid metabolism, and metabolic diseases has been well reviewed in humans. However, the interplay between gut microbiota and host metabolism in swine remains incompletely understood. Given the limitation in conducting human experiments and the high similarity between swine and humans in terms of anatomy, physiology, polyphagy, habits, and metabolism and in terms of the composition of gut microbiota, there is a pressing need to summarize the knowledge gained regarding swine gut microbiota, its interplay with host metabolism, and the underlying mechanisms. This review aimed to outline the bidirectional regulation between gut microbiota and nutrient metabolism in swine and to emphasize the action mechanisms underlying the complex microbiome–host crosstalk via the gut microbiota–gut–brain axis. Moreover, it highlights the new advances in knowledge of the diurnal rhythmicity of gut microbiota. A better understanding of these aspects can not only shed light on healthy and efficient pork production but also promote our knowledge on the associations between gut microbiota and the microbiome–host crosstalk mechanism. More importantly, knowledge on microbiota, host health and metabolism facilitates the development of a precise intervention therapy targeting the gut microbiota. 相似文献
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炎热的夏季常引起奶牛发生"热应激"而导致其产奶量下降和发病率增高。因此,如何在夏季保持奶牛高产,是养殖户亟需解决的一个难题。 相似文献