Case control study of fowl cholera in meat turkeys in California from August 1985 through July 1986 [corrected

From Aug 1985 through July 1986, 720 meat turkey flocks on 160 California premises were monitored and outbreaks of fowl cholera (Pasteurella multocida) were investigated. Data from 43 outbreak (case) flocks were compared with data from 43 nonoutbreak (control) flocks. Outbreak flocks, compared with control flocks, were more likely to be located on premises with higher maximal bird capacity and history of fowl cholera outbreaks. The overall impression was that flocks in larger, newer, more intensively managed premises were at greater risk of fowl cholera outbreaks than were other flocks.     

Characteristics of fowl cholera outbreaks in turkeys in Georgia in 1986

Information was gathered from 64 cases of fowl cholera (FC) in turkey flocks through diagnostic case records, flock records, and telephone and mail surveys. Forty-five cases came from flocks of commercial turkeys, of which 15 were presented twice, and four came from mature breeder flocks. The prevalence of FC was 18.0% of commercial flocks and 14.7% of breeder flocks at risk. The average age at first diagnosis of FC was 90 days in commercial turkey flocks and 32 weeks 5 days in breeder flocks. Acute mortality was the most common presenting complaint, with a 0.37% average mortality in commercial flocks on the day of first presentation, 0.80% in commercial flocks presented a second time, and 0.43% in breeder flocks. Pasteurella multocida was cultured from 69.8% of the 361 tissue samples submitted from these cases. Novobiocin, penicillin, and chlortetracycline (CTC) had the greatest in vitro activity against isolates. Serotype 3-cross-4 was found in all 18 commercial flocks from which isolates were typed. All breeder flocks and 88.6% of commercial flocks were vaccinated before disease onset. Flocks were treated for an average of 14.3 days, most commonly with high levels of sulfadimethoxine and/or CTC. Body weights of affected birds were comparable to those of birds in unaffected flocks, but mortality and feed efficiency were worse.     

Relationship of increased fowl cholera outbreaks in turkeys with high environmental temperatures.

The relationship of an increase in fowl cholera outbreaks in turkeys with an increase in environmental temperatures during June, July, August, and September between 1959 and 1992 was analyzed. High environmental temperatures were found to be influential in the development of fowl cholera in turkeys. When the average monthly maximum environmental temperatures for 5 mo of July and 7 mo of August during the 13 yr between 1967 and 1979 were above 30.5 C, there was a significantly (P < 0.05) higher number of fowl cholera outbreaks in turkeys for each month than during the same months when the average maximum temperatures were below 30.5 C. To test the hypothesis that an increase in fowl cholera outbreaks was preceded by an increase in temperature, the pre- and postoutbreak temperatures for 46 selected outbreak clusters occurring between 1959 and 1992 were averaged. Both the average maximum and minimum temperatures for the latter 9 days of the preoutbreak period were highly significantly (P < 0.001) higher than those of the average cluster outbreak day and the following four postoutbreak days. Also, for the nine individual days of the latter pre-outbreak period, the daily average maximum temperature was significantly (P < 0.05) higher for 3 days and partially significantly (P < 0.10) higher for 3 days than that of the average cluster outbreak day, and the daily average minimum temperature was significantly (P < 0.05) higher for 2 days and partially significantly (P < 0.10) higher for 1 day than that for the average cluster outbreak day.     

DNA fingerprinting of plasmid-containing serotype A: 3,4 Pasteurella multocida isolated from cases of fowl cholera in chickens and turkeys

The live, attenuated vaccine strains of Pasteurella multocida have been hypothesized to be responsible for homologous serotype outbreaks of fowl cholera on farms that use the commercial vaccines. We have further hypothesized that the naturally occurring Clemson University (CU) vaccine strain may be transformed to virulence by the acquisition of plasmid DNA. To test this hypothesis, we obtained seven homologous serotype (A:3,4) P. multocida isolates, all plasmid bearing, that were cultured from fowl cholera cases in vaccinated flocks and compared the isolates with the CU reference vaccine by molecular methods. Restriction fragment length polymorphisms (RFLPs) were detected by DNA/DNA hybridization with labeled probes specific for the cya, aroA, and rrn genes of P. multocida. The RFLPs obtained from BglII-digested genomic DNA probed with cya demonstrated no differences among the isolates. Although three isolates probed with aroA showed a RFLP identical to the vaccine strain, five isolates were distinctly different. Isolates probed with rrn grouped into three different restriction patterns that were dissimilar from that of the vaccine strain. Therefore, we have shown that these fowl cholera isolates are different from the CU vaccine strain and that these outbreaks were not vaccine related.     

A descriptive study of mortality at the Kortright Waterfowl Park: 1982-1986

A five year survey of mortality in an Ontario waterfowl park was conducted. The highest mortality rate was in birds under seven weeks of age, with infectious disease most frequently diagnosed. In older birds, amyloidosis and gout were most common. Associations were found between the presence of amyloid and the diagnoses of gout, enteritis, and arthritis. Specific data collection requirements for studies of this type, and the difficulties involved, are outlined. Recommendations for increasing productivity, including the implementation of sanitation programs, and improvements to the record-keeping system, are made.     

禽霍乱病诊治

禽霍乱是由多杀性巴氏杆菌引起家禽一种急性败血性传染病。该病发病急,传播快,发病率死亡率高,诊治不及时会造成很大经济损失。下面就我市新风村一养鸡户,发生禽霍乱病诊治情况介绍如下。     

Homogeneity of characteristics of Pasteurella multocida isolated from turkeys and wildlife in California, 1985-88

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.     

A new serotype of Pasteurella multocida associated with fowl cholera

Gel-diffusion precipitin tests demonstrated an additional Pasteurella multocida serotype, designated serotype 16. Isolate P-2723, antigenically distinct from the other (previously reported) 15 serotypes, was from a turkey affected with fowl cholera. This serotype is not widely distributed. Isolate P-2723 was of mild virulence in turkeys, resulting in local infections in the hock joint and sternal bursa of only 1 of 9 turkeys exposed.     

Avulsion of the common retinaculum in meat turkeys

An increase in leg condemnations was experienced in several commercial meat flocks of male and female turkeys. Affected legs had hematomas around and above the tibiotarsus-tarsometatarsus (hock) joint. Avulsion of the common retinaculum from the external condyle was observed when the skin and muscular fascia were removed. A farm investigation was performed and similar changes were observed in turkeys between 10 and 19 wk of age. Interestingly, birds with avulsion of this fibrinous bridge were not lame. Body weights were normal, no infectious agent was detected, and mineral contents of bones and tendons were within normal limits. Avulsion of the retinaculum might not have been diagnosed in the past because the birds are not lame and the lesion is tightly covered by the skin and muscular fascia.     

艾维茵肉鸡暴发禽霍乱的诊治

禽霍乱又称禽巴氏杆菌病,是由某些血清型的多杀性巴氏杆菌引起的鸡鸭鹅等禽类的接触性、败血性传染病,发病率和死亡率都很高,是禽类常见病之—,对养禽业的危害甚大。我市双流区某养殖户王某2004年2月购进艾维茵肉雏鸡2500余只,养至30日龄左右部分鸡只发生禽霍乱,经正确诊断和采取有效的防治措施,取得了良好的效果,现将情况报道如下:1发病情况该养殖场采用笼养方式饲养的30日龄左右的艾维茵肉鸡,部分突然出现精神不振、呼吸困难、喜饮水、剧烈腹泻等现象,经检测,新城疫、传支、传喉的抗体滴度属正常。当时饲料中加入地克珠利和饮水中加入氟哌…     

慢性禽霍乱和葡萄球菌引起蛋鸡脚垫坏死

蛋鸡脚垫坏死往往与饲养条件和饲养环境有关,而慢性禽霍乱和葡萄球菌感染多见有胃肠炎、关节炎以及呼吸道症状。 去年5月在我市胡庄镇某村发生了一起由慢性禽霍乱和葡萄球菌引起蛋鸡脚垫坏死的病例。现报告如下：     

防治种鸡暴发里氏杆菌的有效措施

1997年2月,广西玉林市某种鸡场发生了急性黑氏杆菌病,疫情从肉鸡群迅速传播到整个种鸡群,并持续近半年,造成了严重的经济损失.现将发病情况及防治措施报告如下:     

Feline hyperthyroidism: A descriptive and case-control study

The frequency of diagnosis of feline hyperthyroidism has increased dramatically since the late 1970s. Whether this increase reflects enhanced diagnostic acumen or an actual increase in the incidence of this disease, or both, is unknown. It seems likely, in view of the distinctive nature of the signs and the lack of evidence of thyroid enlargement and clinical signs in previous feline necropsy series, that feline hyperthyroidism is truly occurring with increased frequency today.

A case-control study was undertaken to identify possible risk factors for this disease. Owners of 56 cats with feline hyperthyroidism and 117 controls were questioned about their cats' exposure to various potential risk factors (e.g., diet, medications) and these exposures were compared. Elevated odds ratios were associated with regular treatment with flea sprays or powders, living strictly indoors and having reported exposure to lawn herbicides, fertilizers or pesticides. Cases were also more likely to receive canned food and were less likely to be Siamese than controls. The relevance of these factors to the etiology of feline hyperthyroidism is discussed.     

An outbreak of fowl cholera in ring-necked pheasants (Phasianus colchicus)

A total of 120 ring-necked pheasants from a 3000-bird flock in Zeeland, MI, died over a 3-day period. Clinical signs included sudden death, diarrhea, and limping. At necropsy, hepatomegaly with multifocal cream-colored foci randomly distributed throughout the parenchyma was observed in diseased birds. Additionally, the spleen was enlarged up to three times its normal size and had a marbled appearance. Microscopically, there was multifocal splenic and hepatic necrosis with intralesional rod-shaped bacteria. Pasteurlla multocida serotype 3/4 was isolated from liver and spleen. In this paper, we report an outbreak of acute fowl cholera in ring-necked pheasants.     

Pasteurella multocida in wild mammals and birds in California: prevalence and virulence for turkeys

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.