首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
A combined culturing medium has been developed and has proved to clearly increase rates of detection of avian mycoplasmas, as compared to mycoplasma culturing media previously used in the GDR. The medium can be used to culture all mycoplasma species relevant to turkey. Experimental studies have shown that pH values should be between 7.0 and 7.2 in liquid culturing media and should not exceed 7.2 in mycoplasma agar, in order to be capable of isolating, in cases of mixed infections, not only Mycoplasma (M.) meleagridis but also M. gallisepticum. Culturing media should be incubated at 38.5 degrees C. The living animal should best be diagnosed by examination of palatine and cloacal swabs, with sperm being additionally checked of insemination cocks. A monitoring programme has been drafted for mycoplasma-free broods of turkey parents.  相似文献   

2.
Cloacal and pharyngeal swabs from 100 tree-nesting Double-crested cormorant (DCC) chicks were examined by culture for commensal and potentially pathogenic bacteria. No Salmonella or Erysipelothrix were isolated from the cloacal swabs. Twenty-two cloacal swabs were positive for Campylobacter, of which 14 were C. jejuni, C. coli, and 1 C. lari. None belonged to common serotypes isolated from humans or animals in recent years in Canada. Tests for antimicrobial drug resistance among 187 commensal Escherichia coli isolates from the cloacal swabs indicated that < or =5% were resistant to any of the 12 antibiotics tested. This contrasts with the frequently high resistance rates among E. coli isolates from poultry. Pharyngeal swabs from DCC were negative for Pasteurella multocida. Culture of cloacal swabs from 100 ground-nesting DCC chicks resulted in the recovery of 19 Salmonella isolates, all of which were S. enterica serotype Typhimurium. None of these isolates were resistant to any of the 12 antibiotics tested. Altogether, these findings suggest that DCC from this region are not being colonized with commensal or potentially pathogenic enteric bacteria from agricultural or human sources and that enteric bacteria isolated from these birds are unlikely to contribute to a gene pool of antimicrobial drug resistance.  相似文献   

3.
An investigation into the health and husbandry of 15 small poultry flocks was undertaken. Each flock was visited in July and a questionnaire on management practices and disease history was completed. The flocks were clinically examined and serological tests for Salmonella pullorum, Mycoplasma gallisepticum, M synoviae, M meleagridis, Newcastle disease, infectious bursal disease, infectious bronchitis, eggdrop syndrome 76, adenoviruses and reoviruses were carried out. Oesophageal and cloacal swabs were cultured for mycoplasma and pullorum reactors were cultured. M gallisepticum, M synoviae, M meleagridis and M gallinarum infections were detected and serological reactions for all the viral diseases, except egg drop syndrome 76, were found. Evidence of Newcastle disease and pullorum disease was encountered. Lice were present in five flocks and mites in four flocks. Welfare standards varied.  相似文献   

4.
Hyperplasia and hypertrophy of fat cells of the subcutaneous adipose tissue were studied in different production types of fowl in the post-incubation period. The cocks and hens of laying type were found to have fewer and smaller fat cells than the birds of broiler type. The highest hyperplasia was recorded in the first nine weeks of age, then followed a decrease, lasting until the 25th week. Hypertrophy continued step by step throughout the period of study and increased when hyperplasia decreased. The differences between sexes increase during sexual maturation: in the hens the hypertrophy of cells increases and hyperplasia does not decrease so quickly as in the cocks. Before sexual maturity, hypertrophy as well as hyperplasia are somewhat higher in the cocks.  相似文献   

5.
Chlamydophila psittaci (C. psittaci) infection was evaluated in 77 free-living nestlings of Blue-fronted Amazon parrots (Amazona aestiva) and Hyacinth macaws (Anodorhynchus hyacinthinus) in the Pantanal of Mato Grosso do Sul, Brazil. Tracheal and cloacal swab samples from 32 wild parrot and 45 macaw nestlings were submitted to semi-nested PCR, while serum samples were submitted to complement fixation test (CFT). Although all 32 Amazon parrot serum samples were negative by CFT, cloacal swabs from two birds were positive for Chlamydophila DNA by semi-nested PCR (6.3%); these positive birds were 32 and 45 days old. In macaws, tracheal and cloacal swabs were positive in 8.9% and 26.7% of the samples, respectively. Complement-fixing antibodies were detected in 4.8% of the macaw nestlings; macaw nestlings with positive findings were between 33 and 88 days old. These results indicate widespread dissemination of this pathogen in the two evaluated psittacine populations. No birds had clinical signs suggestive of chlamydiosis. To the best of our knowledge, this is the first report on C. psittaci in free-living Blue-fronted Amazon parrots and Hyacinth macaws in Brazil.  相似文献   

6.
One-day-old chickens were inoculated intravenously with one of three low-pathogenicity avian-origin influenza isolates. On day 5 postinoculation (PI), the frequency of influenza virus isolation from cloacal swabs following challenge with each isolate ranged from 83% to 100% for clinically normal euthanatized chickens. Influenza virus was also frequently isolated from kidneys of these chickens (47%) and from chickens that died (100%). Kidneys positive for virus isolation had lesions of nephrosis and/or acute nephritis, and influenza viral nucleoprotein was demonstrated in nuclei and cytoplasm of necrotic renal tubule epithelium. On sampling days 28 and 45/60 PI, influenza virus was neither isolated from nor immunohistochemically demonstrated in kidneys (0/125); however, the kidneys (47%) did have chronic histologic lesions that suggested previous influenza virus infection of the kidneys. Influenza virus was isolated from cloacal swabs of two of 44 chickens on day 28 PI, but all cloacal swabs were negative for virus recovery on sampling day 45/60 PI (0/81). These results indicate that replication of influenza virus in renal tubule epithelial cells did not result in persistence of type A influenza virus in this immunologically privileged site.  相似文献   

7.
Histomona meleagridis is a protozoan parasite that may cause outbreaks of histomonosis with high mortality, especially in turkey flocks. Chickens are less susceptible to the disease than are turkeys, but are considered to act as an important reservoir. To determine the seroprevalence of H. meleagridis in Dutch layer chicken flocks, a large scale seroepidemiologic study (3376 samples) was performed by sampling 12 organic flocks, 24 free-ranging flocks, 40 flocks with floor housing, and 40 flocks with cage housing. At the end of the laying period, approximately 30 blood samples per flock were collected for serology. The seroprevalence found was high. In every flock, at least one of the samples tested positive while in 87% of the flocks, at least one of the samples was strongly positive. There were no significant statistical differences in seropositivity between the housing types. To confirm the enzyme-linked immunosorbent assay (ELISA) results, a small-scale seroepidemiologic study (576 samples) was performed in 29 additional layer chicken flocks kept in different housing systems. Subsequently, a subset of five seropositive flocks was selected. Five birds were obtained from each of these flocks in order to detect the parasite using culture and PCR. In all five flocks, H. meleagridis was either isolated from (culture), detected in (PCR), or both, the birds sampled. Together with the previously performed validation studies, the latter results confirm that the positive ELISA serology found is genuine. We conclude that the seroprevalence of H. meleagridis in layers is, as anticipated, high.  相似文献   

8.
Histomonas meleagridis infection of turkeys is usually accompanied by a severe disease with unspecific clinical symptoms but with distinct pathological lesions in the ceca and liver. In the literature some macro- and microscopic evidence of the spread of histomonads to the other organs has been provided. The aim of the present investigations was to use real-time polymerase chain reaction (PCR) to demonstrate the dissemination of H. meleagridis DNA to different organs after natural and experimental infection of meat turkeys. Samples from several organs were collected from a meat-turkey flock, which proved to be naturally infected with histomoniasis, and examined for histomonad DNA by real-time PCR. Histomonad DNA was detected in all investigated ceca, livers, spleens, kidneys, and pooled brain swabs. Additionally it was found in 75% of investigated samples from bursae of Fabricius, in 50% of investigated duodenums, and in 40% of investigated jejunum samples. After experimental intracloacal infection of 3-wk-old turkey poults with 147,500 histomonads, similar samples were collected from all turkeys that died. After a 3-wk observation period the surviving birds, as well as the noninfected control group, were euthanatized and samples were taken. During the entire experimental period, 10 birds out the 20 infected birds died. Histomonad DNA was detected in all investigated ceca, livers, lungs, and hearts (100%) and almost all kidneys (90%) and bursae of Fabricius (80%). On the other hand, only 30% of examined spleens and 10% of brain samples revealed positive results. Surviving infected birds were euthanatized and necropsied; histomonad DNA was found in one out of 10 livers but not in any ceca. Also, histomonad DNA could not be detected in examined cecal and lung samples from the noninfected control group.  相似文献   

9.
为了解甘肃省天水市鸡禽白血病的流行情况,本文采用实时荧光PCR方法对2020~2021年采集的24个规模鸡场的480份泄殖腔拭子进行了病原学检测。结果显示,24个规模场中阳性场18个,场点阳性率为73.33%;480份样品中阳性样品203份,样品阳性率42.29%。其中不同用途的鸡禽白血病感染率不同,360份蛋鸡样品中阳性138份,阳性率38.33%;120份肉鸡样品中阳性65份,阳性率54.17%。结果表明,禽白血病病毒在天水市规模鸡场存在普遍流行的现象,且肉鸡的感染率高于蛋鸡。  相似文献   

10.
本试验以80只300日龄的A品系蛋鸡为试验对象,分5个日龄段按翅号采集蛋清、泄殖腔棉拭子,无菌抗凝血和血清.用ALV p27抗原检测试剂盒检测蛋清和泄殖腔棉拭子.将无菌抗凝血分离血浆接种DF-1细胞,培养一周后用同样方法检测上清收集液,分析该群鸡只在不同日龄段泄殖腔棉拭子阳性、蛋清样本阳性和病毒分离阳性之间的相关性.用ALV-Ab抗体试剂盒检测各日龄段血清的抗体水平.此外,选取某一日龄段蛋清和泄殖腔拭子样本用4个不同厂家的ALV p27抗原检测试剂盒进行检测比较.结果表明,5个日龄段泄殖腔棉拭子平均阳性率为61%,蛋清样本平均阳性率为72.6%,病毒分离平均阳性率为48.8%.5个日龄段ALV的抗体阳性率一直为零;4个厂家的ELISA试剂盒对同一批样本的检测结果表明,IDEXX试剂盒的敏感度最高.本试验为外源性鸡白血病病毒检测及鸡白血病净化其方法的应用、试剂盒的选择、减少判定的误差、提高净化效果提供了一定的科学依据.  相似文献   

11.
为探讨不同检测材料对ELISA检测禽白血病病毒(ALV)-p27抗原结果的影响,试验首先对180日龄地方品种母鸡的泄殖腔棉拭子ALV-p27抗原进行ELISA检测,选取部分阳性鸡和阴性鸡进行分组试验,采用ELISA对试验鸡血清、蛋清和病毒分离的细胞培养液进行ALV-p27抗原检测,采用RT-PCR方法检测血液ALV特异性基因。结果显示,阳性组中以血清、蛋清和细胞培养液作为ELISA ALV-p27抗原检测材料,其检测阳性率均低于泄殖腔棉拭子,血清检测的阳性个体包含全部蛋清和细胞培养液ELISA检测的阳性个体。ELISA检测数据的相关性分析显示,只有血清和细胞培养液检测数据间存在显著性相关,线性关系方程为Y(细胞上清)=1.8439X(血清)-0.1469,R2=0.937;阳性组中ALV-p27基因检测阳性率低于泄殖腔棉拭子,但高于血清、蛋清和细胞培养液,其包含所有血清ELISA检测的阳性样品;外源性ALV-J gp85基因阳性率仅为29.17%,且阳性样品均属于血清ELISA阳性样品。综上所述,成年鸡以泄殖腔棉拭子作为ELISA ALV-p27抗原检测材料存在假阳性结果,蛋清和细胞培养液作为检测材料存在漏检的可能,血清作为ELISA检测材能够更准确地反映成年鸡群ALV感染状态。  相似文献   

12.
In order to study the effect of different test materials on the detected results of avian leukosis virus (ALV)-p27 antigen by ELISA, the cloacal swabs ALV-p27 antigen were detected by ELISA in 180-day local breeds hen, and the parts of the positive and negative chicken was selected to group test, the serum, egg whites and cell supernatant ALV-p27 antigen were detected by ELISA, the specific genes of ALV were detected by RT-PCR in blood.The results showed that serum, egg white and cell supernatant as ELISA test materials, the positive rate lower of than cloacal swabs, and serum ALV-p27 positive samples include all egg whites and cell supernatant positive samples in positive group.It was a significant correlation between ELISAs with serum and cell supernatant (linear equation:Y=1.8439X-0.1469, the correl was 0.937).In positive group, ALV-p27 gene positive rate lower than cloacal swabs ELISA, but higher than the serum, egg and cell culture medium, and ALV-p27 gene positive samples include serum positive samples by ELISA.ALV-J gp85 gene positive rate of 29.17%, and all positive samples were included in the serum ALV-p27 positive samples.The results suggested that the cloacal swabs as test material may occur false positive results, and egg whites and cell supernatant may occur undetected by ELISA ALV-p27 antigen assay in adult chicken, serum as test material in ELISA could more accurately reflect the state of adult chickens infected with ALV.  相似文献   

13.
用酶联免疫吸附试验法对长汀河田鸡原种场、武平象洞鸡原种场、龙岩山麻鸭原种场共686份蛋清样本及801份泄殖腔棉拭子进行禽白血病p27抗原检测。结果为:龙岩山麻鸭的蛋清样本和泄殖腔棉拭子均未检出ALV核酸;鸡蛋清样本阳性率为12.8%(80/626),明显高于泄殖腔棉拭子阳性率8.9%(66/741);鸡原种场180日龄蛋清样本和泄殖腔棉拭子阳性率均最高,平均阳性率分别为15.0%和11.3%。表明:龙岩市境内地方优良鸡原种场中有禽白血病感染现象。  相似文献   

14.
1. Effects of rearing conditions on behavioural problems were investigated in a cohort study of commercial flocks of laying hens housed in 2 different loose housing systems. The sample population was 120 385 laying hens from 59 flocks of various hybrids at 21 different farms. 2. Logistic regression modelling was used to test the effects of selected factors on floor eggs, cloacal cannibalism and feather pecking. In addition to early access to perches or litter, models included hybrid, stocking density, group size, housing system, age at delivery, identical housing system at the rearing farm and at the production farm and, in models for floor eggs and cloacal cannibalism, nest area per hen. Odds ratios were calculated from the results of the models to allow risk assessment. 3. No significant correlations were found between the prevalence of floor eggs, cloacal cannibalism and feather pecking. 4. Access to perches from not later than the 4th week of age decreased the prevalence of floor eggs during the period from start-of-lay until 35 weeks of age, odds ratio 0-30 (P<0-001). Furthermore, early access to perches decreased the prevalence of cloacal cannibalism during the production period, odds ratio 0-46 (P=0.03). 5. No other factor had a significant effect in these models. Although it was not significant, early access to litter had a non-significant tendency to reduce the prevalence of feather pecking.  相似文献   

15.
将血管瘤病变型相关的J亚型禽白血病病毒(ALV-J)SCAU-HN06株通过尿囊腔途径接种黄鸡11日龄鸡胚,对其出壳后不同时间点(1、2、3、4、5、6、7、8、9、10、12、14、16、18、20周)的病毒血症、ALV-J特异性抗体及泄殖腔拭子p27抗原分别进行了动态检测。试验结果表明,SCAU-HN06组在1周即检测到病毒血症,7周时有一个高峰,9周后病毒血症阳性率始终维持在80%以上;从6周时开始检测到ALV-J特异性抗体,但监测过程中抗体阳性率最高仅为33.3%(18周),其余均在22%以下;泄殖腔p27抗原阳性率在前3周迅速升高,3周时达到顶峰,随后维持较高的阳性率。由研究结果可知,经鸡胚接种ALV-J的感染黄鸡可导致持续性病毒血症,并容易产生免疫耐受;这项研究可为黄鸡ALV-J的防控与净化提供科学依据。  相似文献   

16.
Serologic testing by the serum plate agglutination (SPA) procedure was performed to detect the presence of cross-reacting antibodies to Mycoplasma meleagridis, Mycoplasma synoviae, and Mycoplasma gallisepticum in lesser prairie-chickens (Tympanuchus pallidicinctus) trapped over a 2-yr period in Finney and Kearny counties of southwestern Kansas. Sera examined from birds (n = 50) obtained in March-April 2000 tested positive for M meleagridis, M. synoviae, and M. gallisepticum at levels of 6%, 10%, and 10%, respectively, for the population examined. Mycoplasma meleagridis antibodies were detected in 3 samples (2.7%), M. synoviae antibodies in 2 samples (1.7%), and M. gallisepticum antibodies in 3 samples (2.7%) from birds (n = 112) collected in March-April 2001. Data obtained by SPA can result in false positives and should be verified by additional procedures such as the hemagglutination-inhibition test. Low amounts of sera prohibited this additional testing. Thus, the positive SPA results should be considered presumptive for the presence of Mycoplasma antibodies. Although Mycoplasma antibodies have been detected in wild turkeys (Meleagris gallopavo) from Kingman and Butler counties in Kansas, this report is the first of possible mycoplasmosis in Finney and Kearny counties, Kansas. All birds testing positive by this procedure should be considered as potential carriers of Mycoplasma and should not be used in relocation efforts.  相似文献   

17.
Following EDS'76 virus (BC14 virus) infection of breeder chickens by the conjunctival route, vertical transmission occurred in the first week after infection. In the progeny which had been infected with EDS'76 virus by the vertical route, increasing haemagglutination inhibiting (HI) titres to BC14 virus and increasing numbers of birds with HI titres were observed from 3 weeks to 15 weeks of age. Sixty-one per cent of the hens and 77 per cent of the cocks had 2 log HI BC14 virus titres exceeding 4 at an age of 15 weeks. Some birds which han been serologically negative throughout the rearing period, seroconverted between 25 and 28 weeks of age. This phenomenon occurred in hens as well as in cocks. Simulation of stress twice during the laying period by injection of corticosteroid hormone did not increase the number of birds serologically positive to EDS'76 virus. EDS'76 was observed in the group of hens that was vertically infected, since egg production was significantly depressed between 28 and 34 weeks of age. Probably this was mainly the results of a production drop in the hens showing serconversion at 27 or 28 weeks of age. In this group of fowl vertically infected with EDs'76 virus, serologically positive birds appeared to be protected for the greater part to BC14 virus challenge at 50 weeks of age, while negative birds seemed to be fully susceptible. Chicks hatched from eggs collected in the third and fourth week after infection of the dams had maternal antibodies. Fertility and hatchability of apparently normally shelled eggs seemed not to be affected after BC14 virus infection of the dams. Intensive contact with contaminated faeces is probably an indispensable condition for lateral transmission of the virus.  相似文献   

18.
An adenovirus was isolated from intestinal samples of two long-tailed ducks (Clangula hyemalis) collected during a die-off in the Beaufort Sea off the north coast of Alaska in 2000. The virus was not neutralized by reference antiserum against known group I, II, or III avian adenoviruses and may represent a new serotype. The prevalence of the virus was determined in live-trapped long-tailed ducks at the mortality site and at a reference site 100 km away where no mortality was observed. Prevalence of adenovirus antibodies in serum samples at the mortality site was 86% compared to 10% at the reference site. Furthermore, 50% of cloacal swabs collected at the mortality site and only 7% of swabs from the reference site were positive for adenoviruses. In 2001, no mortality was observed at either of the study areas, and virus prevalence in both serum and cloacal samples was low, providing further evidence that the adenovirus was linked to the mortality event in 2000. The virus was used to infect long-tailed ducks under experimental conditions and resulted in lesions previously described for avian adenovirus infections and similar to those observed in long-tailed duck carcasses from the Beaufort Sea. The status of long-tailed ducks has recently become a concern in Alaska due to precipitous declines in breeding populations there since the mid-1970s. Our findings suggest that the newly isolated adenovirus is a disease agent and source of mortality in long-tailed ducks, and thus could be a contributing factor in population declines.  相似文献   

19.
Tissue tropism properties of A/chicken/Alabama/75 (H4N8) were examined after intravenous inoculation of 5-week-old specific-pathogen-free chickens. From 14 clinically normal chickens euthanatized on days 1-20 postinoculation, the frequencies of virus recovery were highest for cloacal swabs (86%), bursal swabs (64%), and kidney tissues (64%) and lowest for tracheal swabs (14%), thymus tissues (14%), bone-marrow swabs (7%), and brain tissues (0%). Evidence that the high frequency of virus recovery from kidney tissues was associated with virus replication in the kidney tissues was provided by high virus titers, ranging up to 10(9.5) mean embryo infectious dose per gram of kidney tissue, and by identification of intranuclear and intracytoplasmic type A influenza nucleoprotein in kidney cells using immunohistochemistry. Virus-recovery and virus titer results from three chickens that died on days 4 and 5 postinoculation paralleled the results from the clinically normal chickens. These findings indicate that A/chicken/Alabama/75 has nephrotropic properties similar to nephrotropic properties previously reported for waterfowl-origin type A influenza viruses and provide evidence that kidney lesions could be manifestations of systemic influenza infections in commercial laying chickens.  相似文献   

20.
Five antigen capture immunoassay test kits, Directigen Flu A (Becton Dickinson), QuickVue Influenza test kit (Quidel), FLU OIA (ThermoBiostar), Zstat Flu (ZymeTx, Inc.) and NOW FLU A Test (Binax) were used to detect avian influenza virus (AIV) in clinical specimens as per manufacturers' protocols. Each kit was shown to be specific for AIV propagated in embryonating chicken eggs (ECE); other respiratory viruses of poultry tested gave negative results. The Directigen Flu A kit proved to be 10-fold more sensitive than the other kits, capable of detecting 10(4.7) mean embryo lethal dose (ELD50)/ml in allantoic fluid; this is more sensitive than the hemagglutination test using chicken erythrocytes. None of the kits proved to be sufficiently sensitive to reliably detect AIV in oropharyngeal and cloacal swabs collected from chickens experimentally infected with AIV subtype H6N2. In two different experiments, individual swabs and pools of five or six swabs were tested. By virus isolation, 39 individual oropharyngeal swabs tested positive for AIV, but Directigen and Flu OIA only detected 2/39 and NOW FLU A 1/39. Zstat and QuickVue did not detect any. Five individual cloacal swabs positive by virus isolation were negative with all five kits. In a second experiment using pools of five swabs, 26 swab pools were positive by virus isolation and 5/26 were positive by Directigen, the only kit to provide any positive results. Five cloacal swab pools were also positive by virus isolation and 1/5 was positive by Directigen; all other test kits were negative. All of these experiments were performed using the H6N2 subtype of AIV. The results are disappointing, as the kits have proven to be insensitive for detecting AIV when compared with the gold standard, virus isolation. This limits their use in diagnostic field investigations. Individual or groups of chickens could be assumed to be positive for AIV if positive by any of the kits, but a negative result with any of the kits would not prove that birds were AIV free.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号