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1.
Pasteurella multocida isolated from turkeys during an outbreak of fowl cholera was characterized by serotype and heterogeneity of genes encoding rRNA (ribotype) to investigate the epidemiology of the organism. Isolates were collected between October 1985 and July 1986. The M9 or Clemson University fowl cholera vaccine-like strain was detected in 17% of the flocks with fowl cholera. One particular strain, isolated only from breeder flocks, was recovered from 7 of the 10 breeder flocks examined in this study. Intracompany transmission appeared to be common, implying a failure in biosecurity. Circumstantial evidence indicated that in the field; the incubation period of P multocida in a turkey flock may be between 2 to 7 weeks. Wildlife did not appear to be an important reservoir of P multocida for turkeys during this study period. Ribotyping results tended to discount several of the possible interflock transmissions, as suggested by examination of serotyping results alone; however, serotyping in combination with ribotyping proved helpful in understanding the epidemiology of P multocida in turkeys.  相似文献   

2.
Broiler breeder chickens were exposed to avirulent Pasteurella multocida at 14, 22, and 34 weeks of age either by stick wing 1 to 3 times or subcutaneously 3 times. Fowl pox vaccine was mixed with the first P. multocida exposure in some groups. Exposure did not impair egg production or hatch of fertile eggs. Challenge with pathogenic P. multocida serotype 1 at 68 weeks indicated that exposure to avirulent P. multocida 2 or 3 times provided better protection than 1 exposure. Mixing fowl pox vaccine with the avirulent P. multocida did not reduce immunity to fowl cholera or fowl pox.  相似文献   

3.
Growing turkeys were partly protected against fowl cholera 4 days after vaccination with the live Clemson University (CU) strain of Pasteurella multocida administered in drinking water, and they were highly protected from 1 to 4 weeks after vaccination. The commercially available lyophilized vaccine and the freshly cultured vaccine of the CU strain did not differ in the level of immunity induced. Immunity was relatively high in turkeys vaccinated with 1:2 and 1:4 dilutions of the recommended dosage (4 X 10(8) P. multocida) but was significantly (P less than 0.05) lower in turkeys vaccinated with a 1:8 dilution of the recommended dosage. Immunity continued for 13 weeks after the last vaccination in turkeys vaccinated twice 3 weeks apart, but it persisted for only 8 weeks in those vaccinated only once.  相似文献   

4.
Experimental fowl cholera was induced in 60 healthy 10-week-old broiler chickens and 8-week-old turkeys by intramuscular inoculation with approximately 80 colony-forming units (cfu) of Pasteurella multocida X-73 strain and with approximately 70 cfu of P. multocida P-1059 strain, respectively. This method of infection proved to be useful for evaluating the efficacy of anti-microbial medication, by measuring mortality, weight gain, pathological responses and frequency of re-isolation of P. multocida. The efficacies of two different dosing methods, continuous and pulse dosing, were compared. Using the continuous-dosing method, norfloxacin was administered to drinking water at 100 mg/l for 5 days in chickens. Efficacies were slightly improved compared with pulse dosing at 15 mg/kg bodyweight for the same length of time. The opposite was observed in turkeys, to the degree of control of mortality and maintenance of weight gain.  相似文献   

5.
Turkeys exposed to Bordetella avium were vaccinated against fowl cholera with live Pasteurella multocida vaccine. Previous exposure to B. avium resulted in impairment of systemic immunity conferred by the vaccine: 86% of the vaccinated turkeys exposed to B. avium at 1 day old developed lesions or died of fowl cholera after challenge at 15 weeks old with virulent P. multocida. Of vaccinated turkeys not previously exposed to B. avium, only 26% had lesions or died of fowl cholera.  相似文献   

6.
The M-9 and Minnesota (MN) avirulent Pasteurella multocida vaccines were evaluated and compared with the Clemson University (CU) vaccine, which had been shown to be highly effective in preventing fowl cholera in turkeys. Neither the M-9 nor the MN vaccine given in the drinking water was as effective as the CU vaccine in protecting turkeys against challenge with virulent P. multocida. When grown in brain-heart infusion (BHI) agar as recommended, the M-9 was not as efficacious as when it was grown in BHI broth. The M-9 was as effective as the CU vaccine only when grown in BHI broth and given at 10 times the standard dosage. Injection of the M-9 vaccine into the air spaces of the head at a site near the caudal rim of the ear after one vaccination in the drinking water was not as effective for hyperimmunizing potential breeders as was the CU vaccine injected at the same site. A microtiter agglutination test demonstrated a significant (P less than 0.05) correlation between the level of anti-P. multocida antibody found 1 week after vaccination and survival after challenge with virulent P. multocida.  相似文献   

7.
Administered via the drinking water, M-3-G, an attenuated strain of Pasteurella multocida of serotype 1, was found to immunize turkeys and chickens against fowl cholera. Immunity was tested by challenging birds intramuscularly, by palatine cleft swab, or orally after 3 vaccinations. No reactions to vaccination were noted in 390 turkeys in 12 laboratory trials, nor in 20,245 vaccinated in field trials. Chickens showed no vaccination reactions, and immunity was elicited by challenge in a laboratory trial and in face of natural outbreaks in the field, where 11,600 chickens were vaccinated. No vaccination reactions were noted, although most birds involved in the trials were carrying Mycoplasma spp. Immunity was found to last about 10 weeks after the last vaccination. The immunizing properties of M-3-G are compared with the CU strain.  相似文献   

8.
Three California turkey premises that had repeated outbreaks of fowl cholera were studied for periods of 2 to 4 years. Using biochemical, serologic, plasmid DNA, and restriction endonuclease analyses of isolates of Pasteurella multocida from turkeys and wildlife on the premises, strains of the organism were found to be enzootic on two of the premises. On the third, a variety of strains of P. multocida were isolated from fowl cholera outbreak flocks.  相似文献   

9.
An indirect enzyme-linked immunosorbent assay (ELISA) was developed to measure humoral antibody responses of chickens against Pasteurella multocida. A standard indirect hemagglutination (IHA) test was used to compare serologic results with those of ELISA. The ELISA was also used following challenge with P. multocida to compare the efficacy of three commercial fowl cholera vaccination regimens. Although antibody titers measured by ELISA and IHA were highly correlated, ELISA was at least twice as sensitive as IHA. Antibody measured by ELISA and IHA also correlated significantly with protection against P. multocida challenge. No mortality occurred in any of the three vaccinated challenged groups. However, control unvaccinated chickens experimentally infected with P. multocida developed signs of acute pasteurellosis and died by the 10th day post-challenge. Impression smears made of hepatic tissue from all chickens were stained (Wright's stain), and typical bipolar rods characteristic of Pasteurella were identified in smears from unvaccinated challenged controls only.  相似文献   

10.
Samples collected from the oropharynx of wild mammals and birds trapped on 36 turkey farms in California were evaluated for the presence of Pasteurella multocida. A total of 966 animals were collected from 18 premises that had experienced an outbreak of fowl cholera within the past 2-8 months; samples were collected from 16 of these 18 premises within 2-8 weeks of outbreak notification and while the infected flock was still present. A total of 939 animals were trapped from an additional 18 premises that had not reported any outbreaks of fowl cholera within at least 4 months, if ever. Forty-eight isolates of P. multocida, of a variety of somatic serotypes, were recovered from 6 species of mammals and 3 species of birds. On only 2 of 7 premises was the somatic serotype of the isolates obtained from wildlife the same as the isolate obtained from tissues of turkeys that had died of fowl cholera on the same premises. Tests for virulence to turkeys were conducted with 31 of the isolates. Seventeen of these isolates caused mortality in turkeys. Wide ranges in mortality rates and median times to death were observed.  相似文献   

11.
Five hundred twenty isolates of Pasteurella multocida, collected in California from September 1985 to November 1988, were characterized in the laboratory. Characteristics examined included serotype, capsular type, biotype (subspecies), and possession of plasmid DNA. Three hundred thirty-three isolates recovered from turkeys dying from fowl cholera, 88 isolates from liver turkeys in flocks with fowl cholera outbreaks in the recent past, and 99 isolates from wildlife captured on fowl cholera-outbreak and non-outbreak turkey premises were studied in this manner. Characteristics were fairly homogeneous among isolates, especially those obtained from turkeys. The majority of isolates were serotype 3,4, capsular type A, subspecies multocida, and lacked plasmid DNA. Common serotypes of isolates from turkeys and wildlife sampled on the same premises were noted in eight of 13 cases examined.  相似文献   

12.
Fifty-five serotype 3,4 isolates of Pasteurella multocida, isolated from turkeys dead from fowl cholera, were characterized (fingerprinted) genotypically for comparison with the serotype 3,4 live fowl cholera vaccine principally used in turkeys in California. Twenty-three isolates were obtained from turkeys vaccinated with the M9 live vaccine, and 32 additional isolates were from turkeys not vaccinated for fowl cholera. Methods of characterization included restriction endonuclease analysis of chromosomal DNA and ribotyping, a technique for highlighting restriction site heterogeneity of highly conserved ribosomal RNA genes and associated sequences using a radiolabeled rRNA probe. Eight different genotypes or ribotypes were detected in these isolates by the above methods. Of 23 isolates from M9-vaccinated turkeys flocks, 19 were the same ribotype as M9. Thirty of 32 isolates recovered from unvaccinated turkeys were different ribotypes from M9. The remaining two isolates resembled M9 and were recovered from two different flocks placed in succession on a turkey farm where a flock placed previously had been vaccinated with M9, suggesting interflock transmission. Ribotyping and restriction endonuclease analysis appear to be useful tools to aid in the determination of the role that the live vaccine plays in fowl cholera epidemiology.  相似文献   

13.
Restriction endonuclease analysis (REA) of whole-cell DNA was used to determine possible sources of Pasteurella multocida for each outbreak of fowl cholera occurring in turkey flocks in eight commercial poultry companies in California from October 1988 to September 1989. Over this period, 179 isolates of P. multocida were obtained from dead turkeys in 80 meat and breeder flocks on 43 premises. P. multocida was isolated from wildlife on five premises. Isolates were characterized by subspecies, serotype, presence of plasmid DNA, and REA type. In 52 (65%) flocks, all isolates of P. multocida had the same REA pattern as the M9 live vaccine strain following digestion of DNA with the restriction enzyme SmaI. Field strains of P. multocida were obtained from 27 (34%) flocks, and one flock (1%) yielded both M9 and a field strain of the organism. REA of field strains of P. multocida revealed 17 different SmaI REA types. Based on matching SmaI REA types, potential sources of P. multocida were identified for 15 of the 28 flocks infected with field strains of the organism, and transmission between turkey premises was a possibility in only seven flocks.  相似文献   

14.
Swabs of the oropharynges of 801 live turkeys (621 meat birds and 180 breeders), collected from 15 flocks that had experienced an outbreak of fowl cholera and from 12 non-outbreak flocks, were screened for the presence of Pasteurella multocida. Turkeys from outbreak flocks were sampled within 2 to 9 weeks of the outbreak. Forty-nine isolates of P. multocida were recovered from turkeys in 11 of the outbreak flocks, and none were recovered from turkeys in non-outbreak flocks. Isolation rates varied from 0 to 72% of turkeys sampled in a flock. Nineteen isolates were tested for virulence by injecting them intravenously into turkeys, and 14 were lethal. Results demonstrated that for purposes of disease control, meat birds in fowl-cholera-outbreak flocks should be considered carriers of potentially virulent P. multocida for the life of the flock.  相似文献   

15.
In vivo antigen expression by Pasteurella multocida.   总被引：1，自引：0，他引：1  
Pasteurella multocida was purified from the blood of turkeys affected with acute fowl cholera, and membrane preparations from those bacteria were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and visualized on immunoblots. Antigens were detected in the membranes of these in vivo-propagated bacteria that were not detected in membrane preparations of the same P. multocida strain grown in vitro. The unique antigens were detected in the detergent-insoluble phase and were enriched to various degrees by different detergents.  相似文献   

16.
Avian cholera killed an estimated 2500 birds in western Nebraska and eastern Wyoming from 28 November 1985 to late January 1986. Wild mallards (Anas platyrhynchos) suffered the most losses. Other wild waterfowl, wild turkeys (Meleagris gallopavo), a few domestic fowl, and a bald eagle (Haliaeetus leucocephalus) also died. Pasteurella multocida serotype 1 was the predominant isolate from these carcasses. Cold, wet weather persisted throughout the outbreak, but daily losses in the flock of 50,000 mallards using the area were low. Pasteurella multocida was isolated from nasal swabs of 35 of 37 cattle from a feedlot in which many of these mallards were feeding. Eighty percent of the cattle isolates had antigenic characteristics of serotype 3 or serotype 3 with cross-reactivity. Isolates from wild mallards, wild turkeys, and the bald eagle were virulent to game-farm mallards when inoculated subcutaneously, but P. multocida isolates from cattle were not.  相似文献   

17.
Various antigenic extracts of the CU strain of Pasteurella multocida were prepared to determine their suitability as plate antigens for use in the enzyme-linked immunosorbent assay (ELISA) for the detection of fowl cholera antibodies. Antisera from two separate broiler breeder flocks with known fowl-cholera-vaccination histories were collected just before the birds were challenged with virulent strain X-73 P. multocida. A potassium thiocyanate (KSCN)-extracted antigen, a capsular (CAP) antigen, a lipopolysaccharide-protein antigen, and heat-stable, salt-soluble antigen were all suitable as ELISA plate-coating antigens. Filtered and unfiltered sonicates of the CU strain of P. multocida were also suitable ELISA plate antigens. The results suggested that different plate antigens were detecting different populations of antibodies formed in response to fowl cholera vaccinations. When antibody titers were correlated with survival after challenge, the KSCN and the CAP plate antigens placed more nonsurvivors into low-antibody-titer ranges and more survivors (protected birds) into the high-antibody-titer ranges than the other plate antigens.  相似文献   

18.
湖北省某鸡场疑似巴氏杆菌(Pasteurella)感染,从送检病鸡的肺脏和肝脏中分离到1株细菌,通过菌落形态、培养特性、生化试验、16S rRNA序列比对鉴定为禽多杀性巴氏杆菌,并命名为Pm-HB株。动物回归试验表明,10 CFU细菌即可100%致死30日龄SPF鸡,可确诊为巴氏杆菌病。  相似文献   

19.
从六安地区某养鸡场禽霍乱病鸡上分离到1株禽多杀性巴氏杆菌,采用纸片扩散法和试管稀释法分别测定了青霉素钾、土霉素、硫酸卡那霉素、硫酸庆大霉素、硫酸链霉素、复方新诺明、甲砜霉素、氟哌酸、环丙沙星和恩诺沙星等10种药物对分离菌的体外抗菌活性。结果表明分离到的禽多杀性巴氏杆菌对青霉素钾和土霉素耐药;对硫酸卡那霉素、硫酸庆大霉素、硫酸链霉素、甲砜霉素、氟哌酸敏感;对复方新诺明、环丙沙星和恩诺沙星极敏感。两种测定方法得到的结果一致。因此复方新诺敏、环丙沙星和恩诺沙星可作为目前该发病场防治禽霍乱的首选药物。  相似文献   

20.
The oropharyngeal regions of 680 meat turkeys and 55 breeder turkeys from nine outbreak farms, three history-outbreak farms, and 19 nonoutbreak farms in Ohio, Indiana, and Pennsylvania were cultured to determine the prevalence of Pasteurella multocida in turkeys. Pasteurella multocida was recovered from 32 out of 105 turkeys belonging to outbreak farms. Pasteurella multocida was not recovered from either history-outbreak or nonoutbreak farms. Characterization via capsular and somatic serotyping, biotyping, restriction endonuclease analysis, and antimicrobial susceptibility testing was performed on all recovered P. multocida isolates. Pasteurella multocida serotype A:1 and somatic serotype 1 with an un-typable capsular serogroup (UT:1) were the most common serogroups found. All isolates belonged to biotype P. multocida ssp. multocida. EcoRI, HpaII, and HindIII restriction enzyme digestions identified three, five, and five restriction fragment length polymorphism profiles, respectively. A majority of the isolates were susceptible to amikacin, ampicillin, ceftiofur, cephalothin, enrofloxacin, florfenicol, gentamicin, neomycin, novobiocin, oxacillin with 2% NaCl, sarafloxacin, tilmicosin, and trimethoprim with sulphadiazine and resistant to clindamicin, penicillin, tiamulin, and tylosin.  相似文献   

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