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1.
番鸭呼肠病毒病是发生于雏番鸭(半番鸭)的一种新的急性烈性传染病。病原为番鸭正呼肠病毒,与禽呼肠病毒有一定的抗原相关性;病毒对番鸭胚和鸡胚及其成纤维细胞有致病性,对番鸭和半番鸭有强的致病性,主要感染7日龄~45日龄的雏番鸭,发病率为20%~100%,死亡率为10%~95%以上。临床上以软脚、腹泻、生长障碍为主要症状,病变特征为肝、脾等内脏器官形成大量的灰白色坏死灶。病理组织学变化主要为胸腺、脾和法氏囊的淋巴细胞变性和坏死、单核细胞浸润;肝、脑血管周围和肾间质、肺间质、心肌间有淋巴样细胞或/和吞噬细胞聚集。该病原的致弱活疫苗和灭活苗、以及高免血清可有效防治该病的发生。  相似文献   

2.
番鸭花肝的是近年流行的一种新的番鸭疫病,其特征性病变是死亡番鸭的肝、脾、小肠等部位出现灰白色的坏死点,本文自广东省主要疫区分离到几株病毒,这些病毒在番鸭胚上可继代繁殖,其胚液可使番鸭妇病。不同途径感染试验表明该病毒通过肌肉注射、爪垫部注射、口服,同居感染均可使番鸭发病和死亡,并具有典型病变,分离毒不能使半番鸭,本地鸭,鸡发病。  相似文献   

3.
番鸭花肝病是近年流行的一种新的番鸭疫病,其特征性病变是死亡番鸭的肝、脾、小肠等部位出现灰白色的坏死点.本文自广东省主要疫区分离到几株病毒,这些病毒在番鸭胚上可继代繁殖,其胚液可使番鸭发病.不同途径感染试验表明该病毒通过肌肉注射、爪垫部注射、口服、同居感染均可使番鸭发病和死亡,并具有典型病变.分离毒不能使半番鸭、本地鸭、鸡发病.  相似文献   

4.
本试验运用传染性法氏囊病病毒变异 E 株,通过泄殖腔和鼻腔接种 1,8,15,30 日龄雏鸡,通过尿囊腔接种8, 13,18 日龄鸡胚,全面而系统地观察了接毒后不同时间法氏囊的组织形态学变化,探讨了传染性法氏囊病病毒对胚胎发育时期和雏鸡发育时期法氏囊生长发育的影响。结果表明, I B D V 感染后12~48 h,雏鸡法氏囊粘膜上皮细胞肿胀,坏死脱落,淋巴滤泡髓质部及皮质部淋巴细胞不同程度变性、坏死、排空,形成腺管样结构或囊状空泡: 接毒后72~144 h,法氏囊淋巴滤泡淋巴细胞坏死排空,淋巴滤泡萎缩,网状结缔组织大量增生,而胚胎发育时期,法氏囊粘膜上皮肿胀变性,法氏囊淋巴滤泡形成延迟或不完整,淋巴滤泡内淋巴细胞缺乏或空虚,说明传染性法氏囊病病毒变异 E 株对法氏囊造成严重的组织学危害,从而导致法氏囊生长发育阻滞,组织学形态和结构严重受损。  相似文献   

5.
番鸭呼肠孤病毒病雏番鸭实质器官的超微结构   总被引:2,自引:0,他引:2  
对人工感染番鸭呼肠孤病毒发病雏番鸭的心、肝、肺、肾、脾脏、胸腺、法氏囊等7种实质器官的超微结构进行了观察。电镜下发现:心、肝、肺、肾等实质器官出现不同程度的细胞变性、水肿以及局灶性溶解坏死;各器官血管内皮细胞脂滴增多、水肿以至坏死脱落.通透性增加;浆细胞、淋巴细胞和吞噬细胞呈散在或灶性浸润于坏死区和实质细胞间。免疫器官脾脏、胸腺和法氏囊中的部分淋巴细胞、浆细胞坏死和不同程度凋亡,且细胞溶解坏死形成大小不一的坏死灶并被大量增生的吞噬细胞所吞噬,淋巴细胞数量明显减少。上述结果提示,番鸭呼肠孤病毒能导致番鸭免疫抑制。  相似文献   

6.
给28日龄伊莎雏鸡人工接种新城疫病毒后,应用常规病理学检验、细胞化学和免疫组化技术对免疫器官的病理学变化作了研究。接毒12h,法氏囊滤泡的髓质、胸腺小叶的髓质、脾白髓、盲肠扁桃体的淋巴小结及弥散淋巴组织的部分淋巴细胞和网状细胞首先出现核浓缩、胞浆固缩等坏死变化。接毒1~3d(潜伏期),骨髓、法氏囊滤泡、胸腺小叶、脾白髓和红髓、盲肠扁桃体粘膜层及弥散淋巴组织的淋巴细胞、巨噬细胞和网状细胞发生核浓缩、碎裂、胞浆固缩,强嗜酸性等坏死变化。接毒4~6d死亡病例,这些免疫器官的淋巴组织散在呈蜂窝状空泡结构坏死灶(法氏囊为滤泡坏死),进一步崩解成无结构嗜酸性颗粒状物质。这些坏死变化可作为雏鸡新城疫诊断的根据。  相似文献   

7.
本试验全面而系统地观察了传染性法氏囊病病毒变异E株,通过泄殖腔、鼻腔和尿囊腔接种雏鸡和鸡胚后不同时间法氏囊的组织形态学变化。结果表明,病毒感染后12~48小时,雏鸡法囊粘膜上皮细胞肿胀、坏死脱落,淋巴滤泡髓质部及皮质部淋巴细胞不同程度变性、坏死、排空,形成腺管样结构或囊状空泡,接毒后72~144小时,法氏囊淋巴滤泡淋巴细胞坏死排空,淋巴滤泡萎缩,网状结缔组织大量增生,而胚胎发育时期,法氏囊粘膜上皮肿胀变性,法氏囊淋巴滤泡形成延迟或不完整,淋巴滤泡内淋巴细胞缺乏或空虚。探讨了传染性法氏囊病病毒对胚胎发育时期的雏鸡发育时期法氏囊生长发育的影响。  相似文献   

8.
本文探讨番鸭呼肠孤病毒强弱毒株对番鸭免疫器官超微结构的影响。强毒株感染番鸭显微结构变化表现为:各器官不同程度变性、细胞溶解坏死及血管扩张充血,病灶区及血管周围淋巴单核细胞明显浸润;免疫器官脾、胸腺和法氏囊淋巴细胞变性坏死,数量明显减少。脾脏淋巴细胞坏死,数量减少,网状结缔组织显露。而弱毒疫苗株接种后番鸭胸腺、法氏囊、脾脏组织学形态与健康对照鸭一致,均未发现在显微结构上的损伤。表明番鸭呼肠孤病毒强毒严重损伤免疫器官,而弱毒不仅失去对雏番鸭的致病性,而且也失去了损伤免疫器官和免疫抑制能力。  相似文献   

9.
鸡传染性法氏囊病超强毒感染后SPF鸡免疫器官病理学观察   总被引:8,自引:2,他引:6  
IBDV超强毒株LX株接种2周龄SPF雏鸡后,其致病性不同于经典强毒株CJ801株,它主要引起接种鸡全身性炎症反应,法氏囊、脾脏、盲肠扁桃体等免疫器官中大量异嗜性白细胞、巨噬细胞浸润,淋巴细胞严重坏死崩解,胸腺皮质严重萎缩、坏死,骨髓中造血细胞减少、巨噬细胞和脂肪细胞增生。在接种后14d法氏囊淋巴滤泡严重萎缩、淋巴细胞排空形成囊腺样结构,未见恢复正常,其它免疫器官形态基本恢复正常。电镜观察,接种后2和4d可见胸腺淋巴细胞胞浆浓集、染色质周边化形成新月形,表现细胞凋亡特征;在法氏囊坏死淋巴细胞胞浆中可见60nm大小呈晶格排列或散在的病毒粒子。研究初步探明了鸡传染性法氏囊病病毒超强毒的致病机理。  相似文献   

10.
本试验利用透射电镜连续观察了传染性法氏囊病病毒变异 E 株人工感染雏鸡后不同时期法氏囊细胞的超微结构变化,并对法氏囊内 S Ig M , S Ig G, S Ig A 三种抗体生成阳性细胞数量和血液中 Ig M , Ig A, Ig G 抗体水平进行了检测。观察结果表明, I B D V 感染后法氏囊淋巴细胞出现了严重变性、坏死,表现为核染色质浓缩、碎裂、溶解,线粒体溶解呈空泡样结构,其 他细胞器坏死溶解,在法氏囊淋巴细胞、巨噬细胞、网状上皮细胞等细胞的胞浆中可见不同类型和排列方式的病毒粒子。 I B D V 感染后法氏囊内抗体阳性细胞数量和血清中抗体水平均呈现不同程度的下降,揭示雏鸡机体体液免疫功能严重抑制。  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.
14.
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   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  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.
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   

18.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

19.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

20.
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   

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