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1.
饲粮中长期添加和滥用亚治疗剂量的抗生素,引起细菌耐药、菌群失调、药品残留、环境污染等安全问题。随着无抗饲料养殖时代的到来,寻找饲用抗生素替代品成为研究热点。植物提取物是用物理、化学、生物学等方法从天然植物原料中分离提取具有生物活性的一类化合物,具有抗氧化、抗菌消炎,改善消化生理、促生长,增强免疫,调节肠道微生物,改善肉品质等优点,是一种安全、绿色、无耐药、低残留"替抗"产品。本文综述了植物提取物在畜禽无抗养殖中的应用研究进展,为绿色、安全饲用的抗生素替代品的研发及应用提供科学参考和理论依据。  相似文献   

2.
饲用抗生素替代品是当前畜牧业领域的重要研究内容。中草药提取物作为一种潜在的饲用抗生素替代品具有良好的开发应用价值。杜仲叶提取物含有绿原酸、杜仲多糖和黄酮化合物等多种活性功能成分,具有抗菌、抗氧化、调节免疫、调节糖脂和骨代谢等多种生物学功能。本文就杜仲叶提取物的活性成分和生物学功能及其在畜禽养殖中的应用进展进行综述,以期为杜仲叶提取物在畜禽养殖中的应用提供科学参考。  相似文献   

3.
寻找绿色安全的饲用抗生素替代品是近些年来动物营养领域研究的热点。目前,由于植物精油具有抗菌、抗炎、促进生长、无耐药性、无毒副作用、安全度高等优点,已成为极具潜力的饲用抗生素替代品,并已应用于生产。本文主要综述了植物精油的生理作用以及目前在养殖业使用广泛的几类植物精油的生理作用及应用效果,并且论述了植物精油和有机酸复合使用的效果,以期为开发高效安全、绿色的抗生素替代品提供理论依据,为植物精油在畜禽养殖中应用提供参考,从而推动我国畜禽无抗养殖的健康发展。  相似文献   

4.
阳春三月,以"中国畜牧饲料科技未来20年"为主题的2016·北京论坛在北京顺利召开;和煦四月,首届中国饲用抗生素替代品应用技术创新论坛暨中国饲用抗生素替代品产业创新战略联盟成立仪式在宝来利来生物中心举行。减抗是畜牧业发展的必由之路,如何正确认识饲用抗生素替代品、正确引导养殖户健康养殖?绿色、环保的饲用抗生素替代品的未来发展之路将何去何从?特此,本刊记者采访了安佑集团董事长洪平先生、宝来利来生物产业集团董事长单宝龙先生、宝来利来董事·副总裁盛永杰先生、宝来利来研究院院长谷巍博士和白云牧港集团董事长王旭光先生,他们就行业角度、饲用抗生素替代品代表产品、中兽药与微生态结合等角度为大家详细解答……  相似文献   

5.
早在1986年瑞典就率先提出了禁止在肉鸡饲料中使用抗生素,随后抗生素的禁用在世界各地全面展开,自此以来抗生素替代品的研究在动物营养中已受到了越来越多的关注。肠道微生物似乎是饲用抗生素(In-Feed Antibiotics,IFAs)的作用对象,同时抗生素替代品必须有利于维持动物健康和具有一定的促生长作用。本文讨论了六种饲用抗生素替代品对肠道微生物菌群的作用,综述了它们的作用机制和促生长作用,并重点介绍最近几年多位作者以甘露寡糖为抗生素替代品的研究结果。  相似文献   

6.
饲用抗生素的禁用给养殖业带来巨大挑战,寻找饲用抗生素替代品迫在眉睫。海藻提取物具有提高动物生产性能、改善肠道形态、维持肠道微生物平衡、促进免疫器官发育、降低炎症并提高机体抗氧化能力等特点,具有成为饲用抗生素替代品的潜力。本文重点综述了海藻提取物对猪和鸡生产性能、肠道健康、免疫力和抗氧能力影响的研究进展,为海藻提取物在养殖业上的应用提供理论依据。  相似文献   

7.
饲用抗生素及其替代品研究进展   总被引:3,自引:0,他引:3  
杜冰  刘长海 《广东饲料》2005,14(2):19-21
本文综述了饲用抗生素的起源、功效特点、作用机理,饲用抗生素的使用和目前存在的问题及饲用抗生素替代品的种类和发展方向。  相似文献   

8.
《饲料工业》2019,(18):1-4
饲用抗生素危害日益严重,禁用已成世界共识。饲用抗生素替代产品研发迫在眉睫。牛至油是从牛至中提取的植物精油,具有抗微生物、抗氧化、增强机体免疫力、促进消化和改善动物产品品质等功效,是一种具有广阔应用前景的天然抗生素。本文就牛至油的理化性质、生物学功能、作用机制以及在动物健康养殖中的应用进行综述,以期为健康养殖提供理论参考和备选方案。  相似文献   

9.
乳酸菌益生特性及在猪生产中应用研究进展   总被引:2,自引:0,他引:2  
病原菌耐药性和药物残留问题日益受到人们的关注,寻找饲用抗生素替代品已成为研究热点。乳酸菌具备诸多益生特性,可代谢产生抑菌物质,抑制或杀死肠道病原菌,与病原菌竞争肠黏膜黏附位点,调节肠道黏膜免疫,维持肠道屏障功能,改善肠道菌群平衡,改善猪只健康,已成为饲用抗生素潜在的替代品之一。论文综述了乳酸菌生物学特性、益生作用和在猪生产中的应用。  相似文献   

10.
<正>在2017饲料原料暨粮改饲论坛上,中国农业大学呙于明教授作了题为《主要饲用抗生素替代品及其作用机制》的报告。会上,呙教授从纯学术的角度系统介绍了饲用抗生素替代品的作用机制。1所谓禁抗就是怎么对付微生物抗生素的应用效果主要有两点:抗菌、保健,提高存活率;促生长、增产量、提高饲料转换效率。这些都是与我们经济效益密切相关的指标,作为饲料添加剂有非常重要的意义。试验研究表明,在无菌的饲养条件下,抗生素是无效的。因  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.
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   

15.
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   

16.
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.
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.
20.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

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