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1.
维生素A对动物氧化应激的减缓作用机制 总被引：1，自引：0，他引：1
花生四烯酸(ARA)、活性氧和一氧化氮(NO)过量产生可以引起细胞氧化损伤。维生素A可以有效地调控ARA和NO的生成,在减缓氧化应激方面发挥着重要作用。本文主要从提高硒蛋白谷胱甘肽过氧化物酶(GPx)和硫氧还蛋白还原酶(TrxR)的表达和活性、通过TrxR/丝裂原活化蛋白激酶(MAPK)途径和核因子E2相关因子2(Nrf2)/GPx1/核转录因子-κB(NF-κB)途径对ARA及NO进行调节2个方面综述了维生素A对动物氧化应激的减缓作用机制,为深入研究维生素A对氧化应激的调节机制提供理论依据。 相似文献
2.
冬季持续低温引起的冷应激是降低北方畜牧业经济效益和动物福利的重要因素,可诱导动物产生炎症反应和氧化应激危害机体健康。热休克蛋白作为体内重要的分子伴侣蛋白,在维持机体内环境稳态、帮助动物抵抗应激方面有重要作用,低温环境可激活热休克蛋白快速产生,以此在细胞内外对免疫和抗氧化系统发挥重要调节作用：在胞外,具有保护细胞、参与调节免疫细胞功能、激发免疫反应和提高抗氧化酶活性等作用;在胞内,可抑制NF-κB信号通路保护机体免受炎症损伤,上调Nrf2信号通路提高机体抗氧化功能,缓解冷应激对机体造成的负面影响。本文总结了国内外关于在冷应激状态下热休克蛋白对机体免疫和抗氧化功能的调节作用及其机制,并给出部分提高热休克蛋白表达水平的方法,以期为后续畜禽的冷应激理论研究提供参考。 相似文献
3.
<正>奶牛由于高强度代谢很容易受到氧化应激,氧化应激对奶牛的健康和产能具有负面影响,生产中有必要通过添加抗氧化剂来提高机体的抗氧化能力和减少氧化应激对奶牛的损害。氧化应激产生的过量自由基会导致细胞大分子的氧化修饰、功能异常及坏死,称为氧化损伤,另外氧化产物还作为内源的信号分子,对细胞凋亡和炎症起推动作用。机体的氧化应激被看作是一种代谢状态或生理状态的负荷或异常,研究表明氧化应激对动物多种慢性疾病和生产性能造成影响。奶牛容易遭受氧化应激,多个阶段的氧化应激都对奶牛健康和生产性能产生了损害,因此对奶牛氧化应激和抗氧化的研究 相似文献
4.
氧化应激是指机体内抗氧化系统失衡。在氧化应激条件下,动物体内产生大量自由基,当自由基含量超过机体抗氧化系统清除能力时,就会引起自由基堆积,造成氧化损伤,使动物生产性能下降,器官功能受损。近年来,天然提取物在影响动物氧化应激方面的研究受到广泛关注。天然提取物作为一种潜在的动物抗氧化应激剂,具有抗氧化、抗炎和免疫调节等作用,可通过减少自由基生成和提高抗氧化酶活性保护细胞免受氧化应激的损伤,在维持动物正常生理活动和繁殖性能等方面具有积极作用。文章通过对天然植物提取物中抗氧化活性成分及其作用途径进行综述,以期为新型抗氧化剂的开发和应用提供参考。 相似文献
5.
动物氧化应激与免疫的研究进展 总被引：3，自引：0，他引：3
氧化应激是对动物生产造成巨大经济损失的常见问题之一,它是机体自由基生成增加或(和)清除能力降低,引起机体氧化系统和抗氧化系统紊乱,导致自由基在体内积累而引起的氧化损伤过程。然而,机体抗氧化系统与免疫系统密不可分,其中,核转录因子-κB(NF-κB)信号通路是联系2个系统的重要途径。目前,应用外源抗氧化剂改善动物健康和提高肉制品品质的研究较多,如植物多酚、维生素A和维生素E等。但是,这类试验大多思路较窄,着眼点片面,缺乏系统性探讨。本文在详述氧化应激与免疫关系的基础上,对外源抗氧化剂调控机体免疫系统的研究现状进行了分析与总结。 相似文献
6.
氧化应激诱导机体自由基的产生是有氧代谢的一个组成部分。活性氧(reactiveoxygenspecies,ROS)是机体正常代谢过程和某些白细胞群体在疾病防御过程中产生的。越来越多的研究表明,机体组织和细胞产生的氧化损伤会直接或间接诱导许多疾病的发生,进而影响动物健康和福利。高产奶牛的生产性能在一定程度上可通过补充抗氧化剂来优化。概述了氧化应激的研究进展,综述了围产期奶牛氧化应激、抗氧化防御系统及其与炎症反应的关系,以期为进一步揭示抗氧化剂预防免疫功能障碍和宿主组织氧化损伤的分子机理,避免围产期奶牛发生由氧化应激诱导的代谢病和临床型疾病提供新思路。 相似文献
7.
《动物营养学报》2020,(5)
随着我国养殖业的发展,养殖方式逐渐向规模化集约化转变,对畜禽生产性能的要求越来越高,但是在追求养殖效率的同时,畜禽饲养管理过程中易产生多种应激,如断奶应激、运输应激、热应激、冷应激等。大量的研究表明氧化应激是产生各种应激的根本原因。氧化应激可以破坏动物机体的氧化还原系统,导致肠道、肝脏、生殖器官等各种组织器官的损伤和疾病的发生,成为近年来研究的热点。而核因子E2相关因子2(Nrf2)-抗氧化反应元件(ARE)信号通路的激活可以维持动物机体的氧化平衡,提高抗氧化性能,缓解氧化应激。本文通过阐述氧化应激对畜禽组织器官的影响及其产生的机制,并就Nrf2-ARE信号通路抗氧化应激的机理进行综述,为畜禽生产过程中缓解氧化应激损伤、保障动物福利、提高动物的生产性能提供参考。 相似文献
8.
9.
奶牛乳房炎是一种常见的奶牛代谢性疾病,发病率呈逐年上升趋势。目前已证实,氧化应激成为困扰围产期奶牛生产中的一大问题,在诱发奶牛乳腺细胞破坏或功能障碍方面发挥关键作用。主要是由于动物机体抗氧化功能降低导致自由基产生和清除失衡所致,且持续的氧化应激可通过产生大量的氧自由基来攻击细胞,干扰其正常代谢、增殖和分化,并可能进一步诱发机体自身免疫反应,形成瀑布式效应,造成乳腺细胞产生不可逆性损伤。且核因子E2相关因子2-抗氧化反应元件(Nrf2-ARE)信号通路是细胞对抗外源性刺激和氧化损伤的主要机制。本文主要综述了氧化应激、氧化应激与围产期奶牛乳房炎、机体氧化应激的自我调控机制,对于确保奶牛在围产期内能够维持机体健康、发挥正常的泌乳功能和提高生产性能具有重要意义。 相似文献
10.
动物机体内存在氧化还原平衡,正常状态下保持相对的稳态,当环境或自身状态发生改变时,这种平衡可能会被打破,进而引发机体氧化应激。研究发现,引起氧化应激的因素有很多：如环境因素、动物自身状态改变和外源致病菌以及病毒等,这些因素造成的氧化应激对动物的健康状况、生产性能和繁殖功能等方面会产生不同程度的影响,严重时甚至引发动物死亡,因此,寻求和添加安全有效的抗氧化制剂以调节动物氧化还原状态具有重要的现实意义。目前,针对动物氧化应激的营养性添加剂主要有益生菌、维生素、微量元素、激素类和植物类活性物质等。本文对引发动物氧化应激的主要原因和其对动物产生的影响进行了总结,并概括了具有缓解动物氧化应激功能的营养性饲料添加剂,以期为动物氧化应激和其缓解策略的进一步研究提供参考。 相似文献
11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。 相似文献
12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections
of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal
(GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April
2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs
located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming
areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology
laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum
columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying
degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal
abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy
season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different
nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those
observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes.
But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the
results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia. 相似文献
13.
Rassnick KM Gieger TL Williams LE Ruslander DM Northrup NC Kristal O Myers NC Moore AS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(3):196-199
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks. 相似文献
14.
B. Cinar Kul N. Bilgen J.A. Lenstra O. Korkmaz Agaoglu B. Akyuz O. Ertugrul 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(6):449-453
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded. 相似文献
15.
Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects 总被引：1，自引：0，他引：1
Johansson AM Gardner SY Levine JF Papich MG LaFevers DH Fuquay LR Reagan VH Atkins CE 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):887-895
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses. 相似文献
16.
Waruiru RM Thamsborg SM Nansen P Kyvsgaard NC Bogh HO Munyua WK Gathuma JM 《Tropical animal health and production》2001,33(3):173-187
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round. 相似文献
17.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host. 相似文献
18.
Troxel MT Vite CH Van Winkle TJ Newton AL Tiches D Dayrell-Hart B Kapatkin AS Shofer FS Steinberg SA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):850-859
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma. 相似文献
19.
Bazin H 《Comparative immunology, microbiology and infectious diseases》2003,26(5-6):293-308
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing. 相似文献