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1.
抗生素的滥用带来了一系列养殖和社会问题,引起人们的广泛关注,如何替代或减少抗生素的使用成为目前研究的热点.研究表明:益生元具有促进肠道益生菌生长及增强动物机体免疫力等作用,在减少抗生素使用上取得了显著的效果.对目前常见益生元的分类和特性,系统概述益生元在养殖业中的应用,综析了益生元的生理功能及发挥作用机制,探讨益生元未来的发展趋势及方向.  相似文献   

2.
益生元属于非消化性食品源,可以调节肠道微生物的组成及活性。研究报道特别是在幼龄阶段食入益生元有助于肠道微生物区系的建立和免疫功能的完善。益生元具有抗炎的生理效应,从而能增强机体肠道黏膜屏障功能。然而,对此一般我们认为存在两种机制,其中之一就是通过肠道微生物间接发挥免疫调节作用;很少有研究指出其与宿主之间是否存在不依赖于微生物的相互作用。因此,本文将对益生元与机体的相互作用做一个更全面的概述。  相似文献   

3.
益生元是非消化饲料原料由特定的肠道微生物菌群代谢为宿主提供能量,并通过调节肠道微生物菌群防止病原体黏附宿主细胞来影响肠道健康。对鸡只肠道微生物菌群和益生元调节肠道微生物菌群和免疫功能的研究现状进行综述,以便我们更好地了解家禽肠道微生物菌群,对动物健康和生产能力的提高提供理论指导。  相似文献   

4.
肠道菌群逐渐被认为是与犬猫健康密切相关的代谢活性器官,其参与营养物质的消化吸收、机体代谢及免疫等多种生理功能,决定着犬猫整体健康状态。食物营养素作为犬猫肠道菌群的生长基质,在决定肠道微生物组成及代谢方面起着重要作用。宠物食品中除碳水化合物、蛋白质和脂肪等营养成分外,也包括越来越多的微生物靶向成分,如益生菌和益生元等,这些营养素亦能调控犬猫肠道菌群结构及微生物代谢产物的生成,以达到改善宠物整体健康的目的。为此,本文就犬猫肠道菌群特点、功能以及饮食营养素对犬猫肠道菌群的影响进行综述,旨在为营养调控肠道菌群,改善犬猫健康及促进功能性宠物食品发展提供理论依据。 [关键词] 犬猫|肠道菌群|益生菌|益生元  相似文献   

5.
益生元替代抗生素具有改善家禽生长性能、促进畜牧业养殖发展、保障食品安全的作用。目前,已经证明益生元可以正向调节家禽肠道微生物群。益生元可以抑制动物肠道病原体,其发酵和代谢增强,可以刺激有益菌的活性,从而影响短链脂肪酸的合成。文章综述了益生元概念、效果、机制及其在家禽生产中的应用,为益生元类饲料添加剂在家禽生产中的开发提供参考。  相似文献   

6.
随着水产养殖业高密度集约化的迅猛发展,传统抗生素及化学药物在水产养殖业中的使用弊端逐渐显现出来。寻找安全、无毒、无不良反应、不破坏肠道正常菌群结构和水体微生物群系的饲料添加剂已成为水产养殖业亟需解决的问题。合生元因具有益生菌和益生元的双重功效而逐渐受到广泛关注。介绍合生元的组成及作用机制,并对其在水产养殖中的应用进展和存在的问题进行综述。旨在为合生元在水产养殖业中的有效应用提供理论参考。  相似文献   

7.
芽孢杆菌的果寡糖制剂对断奶仔猪肠道菌群的影响   总被引:1,自引:0,他引:1  
当前动物营养研究认为,无论是抗生素(an-tibiotics)、益生素(probiotics)还是益生元(prebi-otics)都会影响动物肠道微生物群落的组成。一般认为,抗生素对肠道微生物具有非选择性杀灭和清除作用,其促生长作用通过消除肠道微生物对动物生长的抑制作用而实现。益生素和益生元或者是两者协同使用的合生素(synbiotics)则是通过人工定向补充有益微生物或者有益微生物的增殖物质来调整和改善肠道微生态,从而有利于提高动物生产性能。  相似文献   

8.
赵怀宝 《饲料研究》2023,(6):101-106
肠道微生物群有助于宿主肠道发挥多种生理功能,对改善猪的肠道健康、提高猪的生产性能具有重要作用。肠道微生物具有很强的可塑性,易受饮食、抗生素的摄入、病原体感染、宿主状况、外界环境等因素的影响。饮食的变化是影响肠道微生物群的主要因素。很多营养素和饲料添加剂具有调控猪肠道微生物的结构组成、促进肠道健康的作用。调节日粮营养素水平、补充饲料添加剂是猪生产中常用干预肠道微生物方法之一。文章综述膳食营养素和饲料添加剂(益生菌、益生元、酶制剂和植物生物素等)对猪肠道微生物群的影响,为其在猪生产中的应用提供参考。  相似文献   

9.
随着畜禽饲养方法的不断发展,饲养者对饲料添加剂的要求越来越高。抗生素作为生长刺激剂已被禁止使用。所以人们开始探索益生元的作用,益生元主要用于维持畜禽肠道微生物群的平衡。主要讨论了益生元的定义,列出了最常用的益生元,并举例说明了其在动物饲料中的作用。  相似文献   

10.
微生态制剂又称为微生物饲料添加剂,主要包括益生菌。益生元、合生元三类制剂。益生菌是活菌;益生元是一类化学物质,不能被宿主消化吸收,也不能被肠道有害菌利用,只能被有益微生物选择性地吸收利用或能促进有益菌的活性或繁殖;合生元为益生菌和益生元按一定比例结合的生物制剂,能同时发挥二者的共同作用。  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.
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.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

15.
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.
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   

17.
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   

18.
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   

19.
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   

20.
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