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1.
Morita Y Maruyama S Hashizaki F Katsube Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(12):1309-1312
Avian tuberculosis accompanied with many tubercular lesions in the liver and spleen was found in a painted quail at a zoological garden in Japan. Mycobacterium avium complex (MAC) serovar 9 without insertion sequence of IS901 was isolated from the liver (1.3 x 10(8) CFU/g), oviduct (9.4 x 10(7) CFU/g), and intestine (1.5 x 10(5) CFU/g). The isolates were inoculated intravenously to chickens. The inoculated chickens showed clinical symptoms of avian tuberculosis. Birds are susceptible to MAC serovar 9 without IS901. 相似文献
2.
In order to know the effect of in vitro passages on the pathogenicity of the Salmonella gallinarum strain INTA 91, a lyophilized culture was compared with the same strain recently isolated from a sick bird. The mean lethal dose (LD50) of the orally administered lyophilized culture was determined as 2.04 x 10(8) colony-forming units (CFU)/chicken. There was no correlation between the LD50 dose and the degree of disease produced; doses 10 or 100 times higher than the calculated LD50 did not produce a more severe disease. In trial 1, chickens were challenged with 1.02 x 10(9) CFU per chicken (5LD50) of the lyophilized strain and reached 52.2% mortality at the end of the assay. In trial 2, three different groups of chickens were infected with a recent isolate of the same strain: 2.04 x 10(8) CFU/chicken, 4.1 x 10(8) CFU/chicken, and 2.1 x 10(9) CFU/chicken (i.e., 1LD50, 2LD50, and 10LD50 of the dose calculated for the lyophilized strain, respectively). These chicken groups presented higher mortality rates (90%, 100%, and 95%, respectively) than previous trials, showing that the S. gallinarum strain used here increased its virulence by in vivo infected chicken passage. In all assays, the disease started after an incubation period of around 5-6 days. To obtain reliable and reproducible results in future challenge experiments, a fixed limited number of in vitro passages of the S. gallinarum strain must be determined. 相似文献
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One-week-old Salmonella-free broiler chicks were subcutaneously immunized and subsequently boosted two weeks later with 2x10(7)cfu 0.5ml(-1) of an 85-kb virulent plasmid-cured spectinomycin-resistant mutant strain (SG9VP(-)Spc(r)) of Salmonella gallinarum 9 (S. enterica serotype gallinarum 9) along with a control group of mock-immunized chickens. The chicks were subcutaneously challenged at 5 weeks of age with 5x10(10)cfu 0.5ml(-1) (5xLD(50)) of wild-type S. gallinarum var. Duisburg (S. enterica serotype gallinarum var. Duisburg). The cellular and humoral immune responses were measured at weekly intervals post-immunization (PI) and post-challenge (PC) using lymphocyte stimulation test (LST), delayed type hypersensitivity (DTH) test, serum tube agglutination test (STAT) and enzyme-linked immunosorbent assay (ELISA). High stimulation indices suggestive of a potent lymphocyte transformation response and high persistent serum IgG titres were recorded in immunized chickens at the termination of the experiment. These findings indicate that the live attenuated mutant vaccine induced a strong cellular and humoral immunity, which may play a role in the protection of fowl typhoid in broiler chickens. 相似文献
5.
Thirty five (35) rats (Rattus norvegicus) were trapped in the area of four egg producing poultry farms and were examined for Salmonella spp., micro-biologically. The samples were taken from liver, spleen and intestinal content. Cultures were made directly in MacConkey Agar, in Selenite broth and Rappaport Vassiliadis at 37 degrees C and 43 degrees C. Five strains of S. gallinarum and one strain of Salmonella subgroup II were isolated from the intestinal content of six rats. An experimental study was also carried out. Ten rats Rattus norvegicus were trapped near poultry farms of N. Greece. No Salmonella could be detected in their feces when examined three times by the Selenite 37 degrees C and Rappaport-Vassiliadis 37 degrees C methods. The rats were orally infected with an 18 hours culture of S. gallinarum (1 x 10(9)/ml microorganisms). One hundred and sixty samples of feces were periodically collected and examined for the isolation of the microorganism by the methods mentioned above. Although not any clinical sign of a disease was noticed, S. gallinarum was isolated from their feces up to 121 days post infection. 相似文献
6.
鸡体内减毒鼠伤寒沙门氏菌的繁殖和免疫反应 总被引：2，自引：1，他引：1
初步研究了cya和crp双基因突变减毒鼠伤寒沙门氏菌(Salmonella typhimurium)在鸡体内的繁殖和免疫反应。1、4或7日龄肉鸡分别经口感染10^8或10^9CFU减毒S．typhimurium X4550，接种后3—4周鸡体内特异性细胞和体液免疫达到最高峰。4日龄口服10^9CFu组免疫效果最佳，但1日龄高剂量组表现增重降低及免疫抑制。28日龄每鸡口服攻击10^10CFU强毒S．typhimurium 50333，各免疫组保护率为100％。同时免疫鸡还能全部或部分阻止沙门氏菌在肝脏和脾脏的繁殖。接种后病毒S．typhimurium在泄殖腔的检出时间为4周左右。 相似文献
7.
Day-old, straight-run broiler chickens were procured from a hatchery located in the Pacific Northwest. The chickens were subdivided individually into nine groups of 20 chickens. The chickens were tagged, housed in isolation chambers on wire, fed commercial broiler feed, and given water ad libitum. Three isolates of Campylobacter jejuni of poultry origin and one of human origin were tested in this study. Various C. jejuni cultures were inoculated into 9-day-old chickens by crop gavage. Four groups of 20 chickens were inoculated at a dose level of 0.5 ml of 1 x 10(2) colony-forming units (CFU)/ml. The other four groups were inoculated with 0.5 ml of 1 X 10(4) CFU/ml. One group of 20 chickens was kept as an uninoculated control group. Four randomly selected chickens from each of the inoculated and uninoculated groups were necropsied at 5, 12, and 19 days postinoculation (DPI). The C. jejuni was cultured and enumerated from a composite of the upper and midintestine and the cecum. Body weights of all chicken groups at 7 days of age and at 5, 12, and 19 DPI were measured and statistically analyzed. No significant differences were present in the mean body weights (MBWs) of 7-day-old, 5 DPI, and 12 DPI male and female broiler chickens inoculated with C. jejuni at both dose levels compared with uninoculated controls. Differences in MBWs of the male and female broilers at 19 DPI were observed in some of the groups. Results of the C. jejuni culture enumeration mean (CEM) of composite intestine samples at 5 DPI from all inoculated chicken groups, irrespective of the dose level, ranged from (2.5 +/- 5.0) x 10(2) to (2.8 +/- 4.8) x 10(5) CFU/g (mean +/- SD). Results of cecum C. jejuni CEM at 5 DPI inoculated at both dose levels ranged from (2.5 +/- 5.0) x 10(6) to (1 +/- 0.0) x 10(7) CFU/g in all treatment groups irrespective of the dose level. CEM results from the composite intestine samples at 12 and 19 DPI increased by 1 log unit, or sometimes more. Results of cecum C. jejuni CEM at 5 DPI inoculated at both dose levels ranged from (2.5 +/- 5.0) x 10(6) to (1 +/- 0.0) x 10(7) CFU/g in all treatment groups irrespective of the dose level. Increases of 2-5 log units in C. jejuni CEM was present in chicken groups inoculated with 1 X 10(2) CFU of C. jejuni, and a 2- to 3-log increase was present in groups inoculated with a higher dose level of C. jejuni at 12 DPI. The results of C. jejuni CEM from cecal samples at 19 DPI were similar to chicken groups at 12 DPI. Campylobacterjejuni was not isolated from the uninoculated control chickens at 5, 12, and 19 DPI. Clinical signs of illness or gross pathologic lesions were not present in any of the chicken groups during this study. No lesions were present on histopathologic evaluations in C. jejuni-inoculated chickens or uninoculated control chickens. 相似文献
8.
To characterize the optimal aerosol dosage of Brucella abortus strain 2308 (S2308) and B. melitensis (S16M) in a laboratory animal model of brucellosis, dosages of 10(3)-10(10) colony forming units (CFU) were nebulized to mice. Although tissue weights were minimally influenced, total CFU per tissues increased beginning at 10(6)-10(7) CFU dosages, with 10(9) CFU appearing to be an optimal dosage for S16M or S2308 aerosol delivery. At 12 weeks after vaccination with 10(7) CFU of B. abortus strain RB51 (SRB51) or saline (control), mice were challenged intraperitoneally (i.p.) (6.4 x 10(4) CFU) or via aerosol (1.76 x 10(9) CFU) with S2308. Mice vaccinated with SRB51 had reduced (P < 0.05) splenic, liver and lung colonization (total CFU and CFU/g) after i.p. challenge with S2308 as compared with control mice after i.p. S2308 challenge. Control and SRB51-vaccinated mice did not differ (P > 0.05) in splenic, liver or lung colonization after aerosol S2308 challenge. Failure to demonstrate vaccine protection was not because of a high aerosol challenge dosage as colonization of spleen and liver tissues was lower (P < 0.05) after aerosol challenge when compared with control mice after i.p. S2308 challenge. 相似文献
9.
为探究甘肃省民勤县某饲养场肉仔鸡腹泻的病原及复方中草药制剂和抗生素分别对分离病原的抑菌效果,对7日龄病死肉鸡进行解剖，通过采集死亡肉仔鸡肝脏、脾脏、心脏进行病原菌分离培养、形态观察、16S rDNA分子鉴定，最终鉴定该病死肉仔鸡为大肠杆菌与沙门氏菌混合感染。抑菌结果显示，复方中草药对分离得到的大肠杆菌、鸡白痢沙门氏菌、鸡副伤寒沙门氏菌均有良好的抑菌效果。10种抗生素药敏试验结果显示，此三株菌同时对氨苄西林、环丙沙星、四环素、恩诺沙星四种药物耐药；鸡大肠杆菌对庆大霉素、阿米卡星敏感，鸡白痢沙门氏菌对链霉素、氟苯尼考、头孢噻肟敏感，鸡副伤寒沙门氏菌对头孢曲松、链霉素、头孢噻肟敏感。上述研究结果为肉仔鸡大肠杆菌与沙门氏菌混合感染的分离鉴定以及科学指导用药提供参考。 相似文献
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Cheng Z Shi Y Zhang L Zhu G Diao X Cui Z 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(12):1295-1298
Two commercial flocks of Chinese partridge experienced increased mortality associated with a wasting disease at 120-day old in June 2006. Postmortem examination of dead chickens consistently showed visceral tissues mainly proventriculus, liver and spleen were diffuse enlargement. Microscopic examination revealed masses of immature lymphocytes with frequent mitotic figures were seen in various tissues including proventriculus, liver, spleen, kidney, heart, lung, thymus and intestine. Reticuloendotheliosis virus (REV) was isolated from each of four blood samples. Viral antigens were observed in cultured CEF (SPF embryos came from the Ji-nan poultry institute) inoculated blood samples via on indirect immunofluorescent assay. Three hundred bp fragments of LTR of REV obtained from liver samples of six chickens by PCR. This disease has not previously been reported in Chinese partridge. Chinese partridge may represent a potential reservoir of infection for other Chinese local chickens. 相似文献
12.
Shinjiro OJIMA Masashi OKAMURA Nana OSAWA Akiko TAMURA Kazuki YOSHIOKA Takashige KASHIMOTO Takeshi HANEDA Hisaya K. ONO Dong-Liang HU 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1147
Salmonella enterica serovar Gallinarum biovar Gallinarum (S. Gallinarum) is a host-specific pathogen causing systemic infection in poultry, which leads to significant economic losses due to high mortality. However, little is known about the dynamic process of systemic infection and pathogenic characteristics of S. Gallinarum in chickens. In the present study, we developed an oral infection model that reproduces the pathology of S. Gallinarum and clarified the host immune response of the infected chickens. Chickens at 20 days of age orally inoculated at a dose of 108 colony forming unit (CFU) showed typical clinical signs of fowl typhoid and died between 6 and 10 days post infection. The inoculated S. Gallinarum rapidly disseminated to multple organs and the bacterial counts increased in the liver and spleen at 3 days post infection. Pathological changes associated wirh inflammation in the liver and spleen became apparent at 4 days post infection, and increased expression of interferon (IFN)-γ and interleuikin (IL)-12 in the liver and spleen did not observed until 3 days post infection. These results indicate that S. Gallinarum rapidly spread to entire body through intestine, and the low-level of inflammatory responses in the liver during the early stage of infection may contribute to rapid, systemic dissemination of the bacteria. Our infection model and findings will contribute to the better understanding of the pathogenic mechanism of S. Gallinarum, and provide new insights into the prevention and control of fowl typhoid. 相似文献
13.
The occurrence of Marek's disease was studied under laboratory conditions in four genetically different groups of chickens (Brown Leghorn, F1 hybrids of the CB x IA inbred lines, pullets of the paternal branch of the grandparent stock of the Hybro meat type, and final hybrids of the White Hisex layer type) after infection with the Georgia strain of Marek's disease (MD) virus, used in two doses (1600 and 16,000 PFU per one bird). MD was diagnosed on the basis of the occurrence of macroscopic tumours; when these tumours were absent in birds which had died within 105 days from infection, the dead bodies were subjected to microscopic examination (peripheral nerves, gonads, skin, bursa of Fabricius, thymus, spleen). The size of the parenterally administered dose of the virus had no significant effect on mortality, occurrence of tumours and the MD virus in any of the groups of chickens tested. However, there was a time shift in the mortality curve in chickens infected with a lower dose. The significantly highest occurrence of MD was recorded in BrL chickens (100%). A somewhat lower occurrence of MD was recorded in the Hisex White chickens (87.8%) and in the CB x IA hybrids (73.8%). However, the dead CB x IA chickens had a higher occurrence of tumours (96.6%) than the Hisex White chickens (77.1%). The lowest MD occurrence was recorded in the pullets of the Hybro meat type (25.5%). The organ most frequently affected by tumours after infection of the birds with the Georgia strain was the liver (24.1%). 相似文献
14.
An atypical strain of Pasteurella gallinarum: pathogenic, phenotypic, and genotypic characteristics.
R Droual R L Walker H L Shivaprasad J S Jeffrey C U Meteyer R P Chin D P Shapiro 《Avian diseases》1992,36(3):693-699
The pathogenicity of a strain of Pasteurella gallinarum isolated in Fresno County, Calif., was compared with the American Type Culture Collection (ATCC) strain. Broiler chickens were inoculated intranasally with 10(7) colony-forming units (CFU) and intramuscularly with 10(5) CFU of each strain. The only notable lesions were in chickens inoculated intramuscularly with 10(5) CFU of the Fresno strain, which developed severe myositis at the inoculation site, pericarditis, perihepatitis, airsacculitis, and synovitis. P. gallinarum was reisolated from these lesions. Phenotypic characteristics of the two strains were identical except in reactions in ONPG broth and fermentation of xylose. Protein-banding patterns for the two strains were identical except for a single band difference in the 35-kilodalton region. Restriction endonuclease analysis confirmed that the Fresno strain was a distinct one. Plasmid analysis revealed that the ATCC strain had two plasmids and the Fresno strain had none. 相似文献
15.
Immunogenicity of an oil-emulsified Escherichia coli (O1:K1) bacterin with an aqueous-phase-to-oil-phase ratio of 1:4 was evaluated in chickens. Chickens were vaccinated subcutaneously with 0.5 ml of the bacterin at 4 and 6 weeks of age. At 8 weeks, the vaccinated chickens and unvaccinated controls were challenged via air sacs with 10(4) colony-forming units (CFU) of homologous E. coli. Vaccinated chickens were protected against active respiratory infection in that they (a) gained body weights comparable to those in unvaccinated, unchallenged chickens, (b) suffered no morbidity or mortality, (c) had gross lesions so mild that the scored values were comparable statistically to the 0 lesion scores of the negative controls, and (d) did not yield E. coli when their heart blood, pericardial sacs, livers, and air sacs were cultured. Unvaccinated challenged chickens had severe respiratory distress, suffered 36% mortality, and had average air sac, pericardial sac, and liver lesion scores significantly (P less than or equal to 0.05) different from both the vaccinated and negative control chickens. Also, the challenge strain of E. coli only was isolated from the affected tissues of 5 of 14 chickens. Protection against active respiratory infection was again demonstrated in a second experiment, though the challenge dose was 1.06 X 10(6) CFU of E. coli. The immunity, however, was partially overcome, as the vaccinated chickens gained less body weight and the scored values for lesions in the air sacs, pericardial sacs, and livers were significantly higher than those of the negative controls (P less than or equal to 0.05). 相似文献
16.
El-Abasy M Motobu M Na KJ Shimura K Nakamura K Koge K Onodera T Hirota Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(8):865-871
The effects of oral administration of sugar cane extracts (SCE) on Eimeria tenella oocysts infection in chickens were studied with 2 different experiments. In Experiment 1, 3-week-old inbred chickens (MHC; H.B15) were inoculated into the crop with SCE (500 mg/kg/day) for 1 day or 3 consecutive days, and then challenged with E. tenella sporulated oocysts (2 x 10(4) cells/chicken). In Experiment 2, 1-week-old chickens were orally administered SCE at the same dose for 3 consecutive days, and then initially infected with E. tenella sporulated oocysts (2 x 10(3) cells/chicken). At 2 and 3 weeks of age, these chickens were immunized intravenously with the mixed antigens of sheep red blood cells (SRBC) and Brucella abortus (BA). At 4 weeks of age, chickens were challenged with E. tenella sporulated oocysts (1 x 10(5)/chicken). Challenged chickens with E. tenella oocysts showed markedly decreased body weight gain/day, severe hemorrhage and great number of shedding oocysts in feces and high lesion scores. Oral administration of SCE and initial infection with oocysts (2 x 10 (3)/chicken) resulted in a remarkable improvement in body weight gain/day, hemorrhage, the number of shedding oocysts and lesion score, compare to other infected groups. In addition, SCE-inoculated chickens with the initial infection showed a significant increase in antibody responses against SRBC and BA and also improvement in decreased relative proportions of Bu-1a(+) and CD4( )cells in cecal tonsil lymphocytes of E. tenella-challenged chickens. Cecal tissues of chickens administered SCE and initially infected with E. tenella oocysts showed lower numbers of schizonts, gametocytes and oocysts than those of infected control chickens. These results suggest that SCE have immunostimulating and protective effects against E. tenella infection in chickens. 相似文献
17.
Endotoxin was detected by the LAL test in the plasma of swine and cattle following in vivo injection of endotoxin in order to evaluate the applicability of the test in veterinary medicine for detection of endotoxemia.Clinical symptoms of endotoxemia occurred after the injection into 3 swine of 0.10–0.25 mg endotoxin/100 kg bwt and after the infusion during 1–1½ h of 2.0–2.2 mg endotoxin/100 kg bwt into 3 calves. The concentration of endotoxin detected by the LAL test in the experimental animals ranged from 0.15 ng to 6.0 ng endotoxin per ml crude plasma. As positive LAL reactions were obtained only in close connection to the administration of endotoxin, clearance of endotoxin to levels below the sensitivity of the test was fast. In spite of the fast clearance, light symptoms of endotoxemia could be seen as long as 24 h after the last sample showing a positive test result. The applied technique for LAL analysis on blood, therefore, was not adequate for detection of endotoxin at sufficiently low concentrations and some possibilities of improving the technique are discussed.Though leukocytosis were found not to influence the outcome of the LAL test on blood, leukocytic mediators released by endotoxin or endotoxin-derived injuries may still have caused the persistence of the symptoms of endotoxemia, and this question is disputed in relation to the benefit of improving the technique.Especielly in the veterinary clinic, great precautions are necessary to obviate false positive test samples resulting from, e.g., external contamination or transient stress caused by excitement, and it is concluded that the possible application of the LAL test for detection of endotoxemia in veterinary medicine is restricted to surveillance of hospitalized animals and to research purposes. 相似文献
18.
Petrie-Hanson L Romano CL Mackey RB Khosravi P Hohn CM Boyle CR 《Journal of aquatic animal health》2007,19(3):151-158
Zebrafish (also known as zebra danio) Danio rerio were injected intramuscularly with Edwardsiella ictaluri at doses of 6 x 10(3), 6 x 10(4), or 6 x 10(5) colony-forming units per gram (CFU/g) or sterile phosphate-buffered saline (sham) or were not injected. Mortality occurred from 2 to 5 d postinjection (dpi) at rates of 0, 76.6, and 81.3% for the low, medium, and high doses, respectively, and E. ictaluri was isolated from dead fish. Survivors were sampled at 10 dpi and E. ictaluri was not isolated. Sham-injected and noninjected controls did not suffer mortality. Histopathology trials were performed in which zebrafish were injected with 1 x 10(4) CFU/g or sham-injected and sampled at 12, 24, 48, 72, and 96 h postinjection for histological interpretation. Collectively, these zebrafish demonstrated increasing severity of splenic, hepatic, cardiac, and renal interstitial necrosis over time. To evaluate the progression of chronic infection, zebrafish were injected with 1 x 10(2) CFU/g and held for 1 month postinjection. Beginning at 12 dpi and continuing for an additional 2 weeks, zebrafish demonstrated abnormal spiraling and circling swimming behaviors. Histopathology demonstrated necrotizing encephalitis. In immersion trials, zebrafish were exposed to low, medium, and high doses (averaging 1.16 x 10(5), 1.16 x 10(6), and 1.16 x 10(7) CFU/mL of tank water) of E. ictaluri for 2 h. Mortality occurred from 5 to 9 d postexposure at rates of 0, 3.3, and 13.3% for the low, medium, and high doses, respectively; E. ictaluri was isolated from dead fish. Channel catfish Ictalurus punctatus exposed to the medium doses suffered 100% mortality, and E. ictaluri was isolated from these fish. This study demonstrates the potential use of zebrafish as a model for E. ictaluri pathogenesis. 相似文献
19.
A S Dhillon B Alisantosa H L Shivaprasad O Jack D Schaberg D Bandli 《Avian diseases》1999,43(3):506-515
Four hundred fifty day-old Hubbard broiler chicks were subdivided into 15 groups of 30 chicks each. Six groups of chicks received 0.5 ml of broth culture containing 5 x 10(6) colony-forming units (CFU) of Salmonella enteritidis (SE) phage types (PTs) 4, 8, and 23 by crop gavage. Similarly, six other groups received 0.5 ml containing 5 x 10(8) CFU of SE. One group was inoculated with 0.5 ml containing 5 x 10(6) CFU of Salmonella pullorum, and another group received 0.5 ml containing 5 x 10(8) CFU of S. pullorum. A group of 30 chicks were kept as uninoculated controls. Chicks were observed daily for clinical signs and mortality. All birds were weighed at 7, 14, and 21 days postinoculation 21 (DPI). Four chicks were randomly selected from each treatment group, euthanatized, and necropsied at 7 and 14 DPI. Gross lesions were recorded and selected tissues were collected for histopathology. The higher rates of illness and mortality were observed in chicks inoculated with 5 x 10(6) and 5 x 10(8) CFU of S. pullorum, followed by SE PT4 of human origin and SE PT4 of chicken origin. Moderate to high mortality was observed in chicks inoculated with the higher dose of SE isolates that belonged to PT8 and one SE of PT23. Variable mortality was evident in groups inoculated with the lower dose of salmonella. The most consistent gross and histopathologic changes, including fibrinous pericarditis and perihepatitis, were seen in the dead birds from various treatment groups. The lower mean body weights were present in all treatment groups compared with uninoculated controls. No illness or mortality was observed in uninoculated control groups. 相似文献
20.
为建立副猪嗜血杆菌(Hps)的感染动物模型,本试验用Hps血清5型标准菌株(Nagasaki),以2.0×10~9CFU剂量腹腔感染豚鼠,观察豚鼠发病及死亡情况.取死亡豚鼠的主要器官组织,观察其病理和组织病理变化,与猪Classer's病痛变进行比较.并同时对死亡豚鼠进行细茵分离,分离菌经PCR鉴定.实验结果显示:在接种14 h后试验组豚鼠(5/8)出现死亡,死亡豚鼠剖检时出现了与猪Classer's病相似的病变;主要组织器官组织学变化以炎性细胞浸润、纤维蛋白和红细胞渗出等变化;并通过细茵分离培养,在豚鼠大脑、心血、肺、肝、脾和肾主要器官中分离到Hps血清5型茵.实验结果表明豚鼠可以作为Hps的感染动物模型.这一结果为研究其致病机制、诊断和免疫研究奠定基础. 相似文献