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1.
实验性鸡大肠杆菌病的超微动态病理变化   总被引:1,自引:0,他引:1  
10~ 12日龄 SPF鸡 180只 ,随机分为 4组 ,分别气管内注射致病性大肠杆菌 O18分离株 (大肠杆菌接种组 )、低致病性禽流感病毒 (mildly pathogenic avian influenza virus,MPAIV) H9N2株 (MPAIV接种组 )、先接种 MPAIV再接种大肠杆菌 (混合接种组 ) ,并设健康对照组 ,分别于接种后不同时间 ,取气管、肺、气囊、胸腺、法氏囊、脾、肝和肾组织 ,制作超薄切片 ,电镜观察。结果表明 ,MPAIV与大肠杆菌混合接种组比大肠杆菌接种组出现病变的时间早、恢复慢 ;在大肠杆菌接种组 ,接种后 3h气囊上皮和间质细胞中都可见典型的大肠杆菌 ;在混合接种组 ,接种后 3h,气囊间质细胞的吞噬泡中可见多个 MPAIV粒子。由此认为 ,MPAIV可使鸡大肠杆菌病严重化 ,大肠杆菌对 MPAIV的入侵和在鸡体内的复制可能有促进作用。  相似文献   

2.
实验性鸡大肠杆菌病病理学动态变化   总被引:6,自引:2,他引:6  
用致病性大肠杆菌O18分离株和/或低致病性禽流感病毒(Mildly pathogenic avian influenza virus ,MPAIV)接种10-12日龄SPF鸡。在接种后1-96h进行临床症状与大体病理变化、组织学观察发现:大肠杆菌接种组、MPAIV接种组和健康接种组除扑杀鸡外未见鸡死亡,MPAIV与大肠杆菌混合接种组除扑杀鸡外死亡率为24%。混合接种组的病变比大肠杆菌接种组出现的时间早,恢复也慢,各脏器的病理变化更严重。MPAIV主要引起各实质器官的坏死,结果表明,大肠杆菌经气管内接种后试验鸡主要表现为呼吸道的炎症反应;MPAVI可使鸡大肠杆菌病严重化。  相似文献   

3.
SPF鸡经不同顺序、不同时间间隔人工感染MPAIV和E.coli 173株(04)后,对试验鸡的病死率和针对大肠杆菌不同抗原体液免疫应答水平等进行研究。结果表明:各混合感染组试验鸡病死率明显高于单独接种组,且以先接种MPAIV再接种E.coli组死亡率最高;各混合感染组试验鸡针对E.coli OMPs和LPS的抗体水平低于单独感染E.coli组,其中又以先接种MPAIV再接种E.coli组为最低,提示MPAIV和E.coli间存在协同致病作用,这种协同机理可能与因MPAIV的感染导致一定程度的免疫抑制并进而促进了E.coli在体内的定居与繁殖有关。  相似文献   

4.
2014年江苏某肉鸡场暴发禽大肠杆菌病,从同一病死鸡个体不同部位分离到禽致病性大肠杆菌(APEC)。为了解同一个体腺胃和心血分离株的致病性,经形态特性、生化试验和血清型鉴定,两分离株均符合O86的典型特征;人工感染显示,两分离株分别以108cfu/m L左胸气囊接种SPF鸡可导致不同程度致病性;病死鸡多个脏器组织可分离到细菌,且腺胃中腺胃分离株的载菌量高于心血分离株,其病理组织学变化涉及肝、脾、肺、肾和腺胃。说明APEC的致病性与其分离部位有一定的相关性,结果为相关禽大肠杆菌病的有效防控提供了新思路。  相似文献   

5.
本试验将30只MG阴性的20周龄的蛋种鸡随机分为4组,Ⅰ组于21和25周龄、Ⅱ组仍于25周龄时分别颈部皮下接种MG油乳剂灭活苗0.5ml/只,Ⅲ组于攻毒后1周接种1ml/只,另设一组对照,不接种疫苗。各组均在29周龄时用通过SPF鸡两次复壮的MG-BG44T株经左胸气囊和鼻腔攻毒。收集攻毒后1-7周内所产的蛋,用PCR方法检测鸡蛋卵黄膜中的MG。结果在攻毒后7周内各免疫组(Ⅰ、Ⅱ、Ⅲ)的垂直传播率显著低于对照组(P<0.01),分别比对照组低26.37%、12.8%、13.64%。攻毒后各免疫组和对照组经4次采样均可从喉头拭子中分离到MG但免疫组的分离率较低。攻毒后第7周从对照组鸡的气管、肺、气囊中均可分离到MG,而试验Ⅰ组仅在气管和肺中分离到了MG。试验Ⅰ组和对照组鸡的输卵管、心、肝、脾和肾中均未分离到MG。  相似文献   

6.
为了建立一种鸡致病性大肠杆菌的快速检测方法,本试验通过无菌采集疑似感染致病性大肠杆菌鸡的心、肝、脾、肾作为病料,经过细菌分离培养、生化鉴定和致病力试验,利用大肠杆菌16S rRNA通用引物对3株致病菌进行PCR扩增,均得到了特异性扩增产物。并对扩增产物进行核酸测序和BLAST比对。结果显示,分离得到3株鸡致病性大肠杆菌(DZMG、DGCG1、DGCP3),扩增出的16S rRNA基因序列与鸡致病性大肠杆菌基因序列同源性为100%。提示该检测方法具有特异性高和简单快捷的特点。  相似文献   

7.
以不同佐剂处理的禽霍乱弱毒活菌液,胸肌接种鸡后,不同时间内剖杀试验鸡,分别采集注射部位、肝、脾、肾、肺、胸腺、胰、脑、法氏囊和心血等组织材料作巴氏杆菌分离。结果表明:(1)禽霍乱活菌在鸡体内器官居留时间十分短暂,在肝、脾、肾、肺居留时间最长只有1—2天;(2)不同时间剖杀试验鸡均末能从胸腺、胰、脑、法氏囊和心血等材料中分离到接种菌;(3)不同佐剂处理的活菌液在注射居留时间,以油佐剂的6—8天为最长,其次是铝胶佐剂的5天,不加任何佐剂的马丁汤稀释菌液在局部居留时间最短,只有1—2天。  相似文献   

8.
用O1血清型大肠杆菌制备负染样品和扫描电镜样品,并对AA鸡气管接种上述大肠杆菌后24小时扑杀取心,肝,气管,肺,肠作透射电镜样品。在透射电镜和扫描电镜下,大肠杆菌呈杆状,两端略呈圆形,内膜为细胞膜,外有细胞壁,周身有较密的菌毛,两端或侧端有细长的波浪形鞭毛,通过细胞膜附着于菌体的胞浆中。在人工感染鸡的心,肝,气管,肺,肠等组织胞浆中都能看到大肠杆菌或在自噬空泡中有降解的大肠杆菌残骸,其中以肺脏的变  相似文献   

9.
本文以潍坊地区送检的病鸡为研究对象,通过鸡胚接种、细菌分离、培养特性、染色特性、生化试验和动物回归实验进行病原的分离与鉴定。结果发现,鸡胚接种后96h内不出现死亡,尿囊液清亮、无血凝性。分离到的细菌为革兰氏阴性小杆菌,经生化鉴定为大肠杆菌。将该分离菌株攻毒30日龄试验鸡,16h内全部死亡,并重新分离出大肠杆菌。这些实验证明本病的病原为致病性大肠杆菌。药敏试验显示分离菌对新霉素、氯霉素、氟哌酸、红霉素、氧氟沙星较为敏感。  相似文献   

10.
腺胃病变型鸡传染性支气管炎病毒强毒株的培育   总被引:3,自引:0,他引:3  
用腺胃病变形鸡传染性支气管炎病毒分离株IBV-D971株接种1日龄SPF鸡,连续传10年代,培育出了腺胃病变型鸡传染性支气管炎强毒株IBV-D971J株。IBV-D971J10对SPF鸡胚的致病力为10^-6.45ELD50/0.2mL,对1日龄SPF鸡的致病力为10^-1.5LD50/1mL,从死亡鸡的心,肝,脾,肺,肾,腺胃,肌胃,法氏囊等均能分离到IBV,IBV-D971J10不含鸡新城疫,禽流感,鸡马立克氏病,鸡传染性法氏囊炎,网状内皮组绢增殖病等外源病毒,对SPF鸡可引起典型的腺胃炎,肌胃炎,间质性肾炎等是变化。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
17.
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   

18.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

19.
正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in  相似文献   

20.
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