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1.
Adult animals from 2 herds were examined clinically and serologically, 5 (Herd A) and 4 (Herd B) times during the same period of 3% years.Serum samples were examined for antibodies against Gorynebac-terium pseudotuberculosis using the bacterial agglutination test (BAT) and the hemolysis inhibition test (HIT).The results of the first examination showed that no animal in Herd A was seropositive, while in Herd B 1 animal showed a high positive titre in BAT. The prevalence of animals with superficial swellings was then 2 % in Herd A and 4 % in Herd B. In both herds, the prevalence of animals with superficial swellings and seropositive reactions increased during the following 1–2 yeairs. About 30 % of animals had superficial lesions and close to 100 % were seropositive. The proportion, of animals with superficial swellings and seropositive reactions was almost constant on subsequent examinations.In some of the animals, superficial swellings were found during 2 or more of the examinations, a few animals having such lesions at the same site on both or all occasions.Animals in Herd A became infected through grazing together with goats from infected herds. Caseous lymphadenitis was introduced into Herd B by animals obtained from infected herds.  相似文献   

2.
Serological examinations for Gorynebacterium pseudotuberculosis in-fection were carried out in 14 known positive herds and in 1 herd that had beeni recently established through purchase of animals from different herds. Serum samples were collected sequentially on up to 4 occasions from animals during their first year of life. In most herds, these animals were examined clinically for superficial swellings once or twice during the same period.The adult goats in 8 infected herds were examined both clinically and serologically. Age distribution was similar in each of these herds. All serum samples were examined for antibodies against Gorynebac-terium pseudotuberculosis in both the bacterial agglutination test (BAT) and the hemolysis inhibition test (HIT).The proportion of kids which were seropositive in both tests de-creased to zero at 4 months of age. At the age of 11–12 months, the proportion of seropositive animals was about 50 % in the BAT and 30 % in the HIT.When examined when housed for the winter at the age of about 8 months (mean age), the prevalence of animals with superficial swellings was 7 %. At the age of about 1 year (mean age), 29 % of the examined animals had such lesions. In the recently established herd, only a few of the yearlings were seropositive.Titre values in BAT and HIT increased until 6 years of age. Anti-body titre values were significantly lower in yearlings than in older goats in both tests, P < 0.005. No significant difference in the propor-tion of goats with superficial swellings was seen at the different ages.  相似文献   

3.
The features of naturally occurring Yersinia pseudotuberculosis serotype III infections in 16 sheep, one goat and 3 pigs, and Y. pseudotuberculosis serotype I infections in 3 goats, are described. Affected animals usually had diarrhoea and were in poor condition or emaciated. A number were moribund or dead when submitted for necropsy. Thickening of the caecal and colonic mucosa was the only gross lesion attributable to Y. pseudotuberculosis infection, with liver or other visceral abscesses not being seen. Characteristic microabscesses were demonstrated in the intestinal mucosa of 10 sheep, one goat and one pig infected with Y. pseudotuberculosis serotype III and one goat infected with Y. pseudotuberculosis serotype I. Sheep, goats and pigs dosed orally with Y. pseudotuberculosis serotype III, the serotype isolated most commonly from these species, developed intestinal infection. In sheep and pigs, infection was accompanied by diarrhoea. Haematological changes and specific antibodies were elicited in all 3 species in response to infection. Microabscesses were seen in the intestinal mucosa of all experimentally exposed animals. The occurrence of field cases and the results of experimental exposure confirm that Y. pseudotuberculosis serotype III is an enteropathogen of sheep, goats and pigs. The association of Y. pseudotuberculosis serotype I with lesions in a goat, indicates that this bacterium may also be a pathogen of this species. It is concluded that Y. pseudotuberculosis serotype III is an enteric pathogen of a wide range of ungulate species including cattle, buffalo, deer, antelopes, sheep, goats and pigs. Serotypes I and II, while having a more restricted host range, are probably also pathogens of ungulates and, in particular, deer, antelopes and goats.  相似文献   

4.
A vaccination trial was carried out in 10 infected herds. The trial included 247 female kids, the number of animals in each herd varying from 15 to 38. About half of the animals in each herd were vaccinated twice at 3 to 4 week intervals, the first vaccination being carried out before the age of 4 months. A combination of a crude filtrate of C. pseudotuberculosis toxoid with whole organisms, was used. Overall, the prevalence of animals with superficial swellings was higher in the unvaccinated than in the vaccinated group during the first 1-2 years following immunization. However, in some herds superficial swellings were as common in vaccinated as in unvaccinated animals. An antibody response following vaccination was demonstrated in the hemolysis inhibition test, but not in the bacterial agglutination test. Superficial swellings were more common in vaccinated animals which were negative than in animals which were positive in the hemolysis inhibition test at 1 1/2 months after vaccination. The vaccine used in the present study, was not sufficiently efficacious to be recommended as the only protective measure against caseous lymphadenitis in Norwegian goat herds.  相似文献   

5.
False-positive results on serologic assays for Mycobacterium avium subsp. paratuberculosis (MAP) are believed to occur due to cross-reacting antibody produced by Corynebacterium pseudotuberculosis (C. pstb) infection in goats. This issue of compromised specificity was evaluated by testing 771 adult goats from 10 Midwestern goat herds in 2004. Assays for MAP infection included radiometric fecal culture and 2 enzyme-linked immunosorbent assays (ELISAs); ELISA-positive samples were tested by agar gel immunodiffusion (AGID). A synergistic hemolysin inhibition assay (SHI) was used to detect C. pstb antibody. Four infection status categories were evaluated. Category 1 goats (free of both MAP and C. pstb infection) tested negative on all MAP fecal cultures and SHI tests. Five of 181 goats were positive in both ELISAs, and 2 more were positive in ELISA-1 only. For Category 2 (MAP infected; no C. pstb infection), all animals were SHI negative. Six goats were fecal culture positive and strongly positive in both ELISAs; 2 more goats were positive only in ELISA-1. For Category 3 (C. pstb infected or vaccinated; no history of MAP infection), all fecal cultures were negative and 91% were SHI test-positive. In this population, only 2 goats were positive in both MAP ELISAs, while 84 additional goats were test-positive only on ELISA-1. In the absence of C. pstb infection, both ELISAs performed comparably, but when C. pstb infection was present the performance of ELISA-1 was significantly perturbed. Use of the ELISA-2 for goats is an effective and efficient method for Johne's disease surveillance in any goat herd.  相似文献   

6.
The precalen-ce of caseous lymphadenitis was surveyed in 36 goat herds in Northern Norway. In each herd, information concerning the occurrence of the disease was obtained from the farmer. Adult animals (1 year of age or older) in 35 herds were examined for superficial swellings, and serum samples were collected from most animals in the herds. The sera were examined for antibodies to Corynebacterium pseudotuber-culosis using the bacterial agglutination test (BAT) and the hemolysis inhibition test (HIT).Gaseous lymphadenitis was diagnosed with certainty in 19 herds. Information from the farmers indicated that the disease indeed oc-curred in these herds, and that the majority had been infected with the disease for many years. The herds had apparently become infected through contact with animals from infected herds. Clinical examina-tions were carried out in 18 of these herds and superficial swellings were found in 26 % of the examined animals. The prevalence of ani-mals with lesions varied from 11 to 40 % among the herds. Of the animals in these herds, 81 % were positive in BAT and 84 % in HIT. The prevalence of positive animals varied from 26 to 99 % in BAT and 28 to 99 % in HIT. The prevalence of seropositive animals was lowest in a herd in which animals were kept separately in stalls.Caseous lymphadenitis could not be diagnosed in 16 herds. In-formation from the farmers indicated that the disease indeed seemed to be absent in 14 of these herds. These 14 herds had no history of contact with animals from herds considered to be infected. However, in the remaining 2 herds, the farmers were somewhat uncertain about the occurrence of the disease. One of these 2 herds had a history of contact with infected herds through participation in a goat “breeding circle”. Only a few of the animals were, however, seropositive and all these had low antibody titres.In 1 newly established herd, a single animal showed a high posi-tive titre in BAT only. All the other animals were negative in both tests. This particular herd consisted of animals obtained both from herds with caseous lymphadenitis and from herds in which the disease was not considered to occur.  相似文献   

7.
Somatic cell counts, the bacteriological condition of the milk and antibodies against caprine arthritis encephalitis virus (CAEV) were measured monthly throughout lactation in 121 lactating goats of the Murcia-Granada breed in four commercial dairy goat herds. The prevalence of bacterial intramammary infection was 5.6 per cent and the prevalence of CAEV infection was 20.6 per cent. An analysis of variance revealed a significant effect of herd, intramammary infection and the interaction between intramammary infection and CAEV on the somatic cell count. In udder halves free of intramammary infection, the somatic cell counts were significantly lower in seronegative goats than in seropositive goats (P<0.05), but the difference was not significant in udder halves persistently infected by bacteria. There was a significant increase in somatic cell counts due to bacterial intramammary infection (P<0.01) in the seronegative goats, but this effect was not present in the seropositive animals.  相似文献   

8.
A survey of caseous lymphadenitis was conducted at a goat and sheep slaughterhouse in Northeastern Brazil One hundred and fifty-eight goats and 43 sheep were examined for the presence of abscesses, with bacterial culturing of purulent material to define the etiological agent. Blood was collected simultaneously for determination of serological titer via the synergistic hemolysis-inhibition test which measures antibodies to an exotoxin of Corynebacterium pseudotuberculosis. Thirteen and nine-tenths percent of the goats had abscesses, with a high proportion having mediastinal or pulmonary lesions (9.5%). Two sheep had abscesses, both with internal organ involvement. Corynebacterium pseudotuberculosis was the most frequently isolated organism. Of 22 goats with abscesses, 20 were positive via the synergistic hemolysis-inhibition test. Both of the sheep with abscesses had positive synergistic hemolysis-inhibition titers. The proportion of serological reactors was greater than the proportion of animals with abscesses. The synergistic hemolysis-inhibition test may be detecting subclinically infected animals.  相似文献   

9.
Two groups of male, 9-week-old goats (5 goats/group) were vaccinated subcutaneously with formalized exotoxin of Corynebacterium pseudotuberculosis, with Freund's incomplete adjuvant. Each goat was given 2 vaccinations, 2 weeks apart. At each vaccination, each group 1 goat was given 0.5 ml of toxoid, and each group 2 goat was given 1 ml of toxoid. Twenty days after the 2nd vaccination, vaccinated goats and 5 nonvaccinated 12-week-old goats (controls) were inoculated intradermally (challenge exposed) with live C pseudotuberculosis, monitored for 13 weeks, and euthanatized. At necropsy, 5 of the 10 vaccinated goats did not have C pseudotuberculosis lesions, 3 had abscesses limited to the inoculation site and draining lymph node, and 2 had disseminated bacterial lesions. Of the 5 nonvaccinated controls, 4 had disseminated abscesses and 1 had a single abscess in an internal node. Serologically, 9 of the 10 vaccinated goats developed positive (greater than or equal to 1:8) antibody titers against the exotoxin within 1 week after inoculation; the 10th goat seroconverted 2 weeks after inoculation, whereas control goats required 3 weeks to develop a positive antibody response. Therefore, early during an infection with C pseudotuberculosis, antibodies against the exotoxin may protect a goat against spread of the organism. All goats were injected intradermally before challenge exposure, 10 days after challenge exposure, and at 4, 8, and 12 weeks after challenge exposure with a skin-test reagent composed of fragmented bacterial cells.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

10.
The synergistic hemolysis-inhibition (SHI) test, a serologic test for the detection of infection with Corynebacterium pseudotuberculosis, was applied to serum samples from 196 goats and 76 sheep, including animals both with and without C pseudotuberculosis abscesses. Fifty-one of 52 (98%) goats and 27 of 28 (96%) sheep with abscesses caused by C pseudotuberculosis had seropositive titers. Seropositivity continued on subsequent samplings, even after superficial lesions were completely healed. The SHI test may detect subclinically infected animals, as well as animals with clinically recognizable lesions. Of the animals without abscesses, 53 of 186 (28%) goats and 4 of 41 (10%) sheep were seropositive. Either the SHI test is lacking in specificity or these titers are a reflection of a past or a current infection without any grossly visible abscesses.  相似文献   

11.
The optimal method of control of caseous lymphadenitis of goats caused by Corynebacterium pseudotuberculosis is eradication of infection by identification and removal of infected carrier animals. The objective of this study was to compare detection of C. pseudotuberculosis experimentally infected goats using a commercially available bovine interferon-gamma (IFN-gamma) whole blood enzyme-linked immunosorbent assay (ELISA) to serological response to a recombinant phospholipase D (PLD) ELISA. The tests were assessed repeatedly over 1 year in three infected and three non-infected goats. Using a IFN-gamma optical density cut-off at 0.10 as positive under the conditions used, the test accurately detected C. pseudotuberculosis experimentally infected goats over a 363 day period with a reliability of 89.2% and non-infected goats with a reliability of 97.1%. Using a cut-off value of the mean for negative samples plus two standard deviations, the PLD ELISA detected C. pseudotuberculosis experimentally infected goats over this period with a reliability of 81.0% and non-infected goats with a reliability of 97.0%. The PLD ELISA was however more predictive than the IFN-gamma ELISA of the presence of lesions observed at postmortem examination of infected goats.  相似文献   

12.
Between 2007 and 2009, the largest human Q fever epidemic ever described occurred in the Netherlands. The source was traced back to dairy goat farms, where abortion storms had been observed since 2005. Since one putative cause of these abortion storms is the intensive husbandry systems in which the goats are kept, the objective of this study was to assess whether these could be explained by herd size, reproductive pattern and other demographic aspects of Dutch dairy goat herds alone. We adapted an existing, fully parameterized simulation model for Q fever transmission in French dairy cattle herds to represent the demographics typical for Dutch dairy goat herds. The original model represents the infection dynamics in a herd of 50 dairy cows after introduction of a single infected animal; the adapted model has 770 dairy goats. For a full comparison, herds of 770 cows and 50 goats were also modeled. The effects of herd size and goat versus cattle demographics on the probability of and time to extinction of the infection, environmental bacterial load and abortion rate were studied by simulation. The abortion storms could not be fully explained by demographics alone. Adequate data were lacking at the moment to attribute the difference to characteristics of the pathogen, host, within-herd environment, or a combination thereof. The probability of extinction was higher in goat herds than in cattle herds of the same size. The environmental contamination was highest within cattle herds, which may be taken into account when enlarging cattle farming systems.  相似文献   

13.
A cohort study of Yersinia infection in goats   总被引：1，自引：0，他引：1  
OBJECTIVE: To determine the temporal pattern of Yersinia infections in three goat flocks and examine the influence of management and seasonal factors on the incidence of those infections over a 1-year period. METHODS: A longitudinal study involving monthly culture of faeces for Yersinia spp. from age groups of randomly selected goats on three farms in the Manawatu region of New Zealand. RESULTS: The incidence of excretion of potentially pathogenic Yersinia (Yersinia pseudotuberculosis and Y enterocolitica biotypes 2, 3 and 5) peaked in winter and fell in summer. In contrast, environmental Yersinia (Y enterocolitica biotype 1A, Y frederiksenii, Y intermedia and Y rohdei) showed no clear pattern of seasonal variation. Pathogenic Yersinia were more prevalent in young animals than in adults, while environmental Yersinia were more prevalent in adults. The same type was isolated from the same animal in two or more successive months in about 20 to 25% of cases, and in the remaining cases there was a gap of at least one month between successive isolations, with many animals yielding a particular type on only a single occasion. A notable difference was that with the potentially pathogenic types, no animal had more than one period of time when it was found to be excreting a particular type, suggesting that immunity develops following exposure. In contrast, it was common for environmental types to be isolated from the same animal throughout the study period. Two goats were suspected to have developed clinical yersiniosis but all remaining infected animals showed no clinical signs of infection. CONCLUSIONS: Asymptomatic Yersinia carriage was common in goats in New Zealand, with a clear seasonal and age group pattern of infection with potentially pathogenic types. There was evidence that immunity developed to potentially pathogenic types. This is the first time that Y rohdei has been isolated from goats.  相似文献   

14.
The effect of an inactivated vaccine against C. pseudotuberculosis infection was tested on castrated male kids from a herd free from caseous lymphadenitis. The animals were divided into 3 groups with 8 animals in each. Group 1 was immunized with crude filtrated C. pseudotuberculosis toxoid and whole killed organisms, while Group 2 in addition was given levamisole. The kids were vaccinated twice at an interval of 4 weeks. Group 3 consisted of unvaccinated animals. All groups were challenged subcutaneously with live bacteria 4 weeks after the last vaccination. Unvaccinated animals showed the most severe course of illness after challenge. Development of abscesses in the regional lymph nodes (Inn. subiliaci) was significantly more common in unvaccinated than in vaccinated kids at necropsy 2 months after challenge. There was, however, no such difference between the vaccinated groups, and there was no difference between any of the groups as regards abscess formation at the inoculation site. In each of the 2 vaccinated groups, there was a titre rise following vaccination in the hemolysis inhibition test, whereas no such rise was seen in the bacterial agglutination test. The titre values in both tests increased significantly after challenge in all the groups, the increase being most rapid in the vaccinated animals. The present investigation indicates that development of caseous lesions in lymph nodes in goats, following subcutaneous inoculation with C. pseudotuberculosis, can be reduced by an inactivated vaccine containing whole organisms and crude toxin.  相似文献   

15.
Caprine arthritis-encephalitis virus (CAEV) was isolated by explant cultures of carpal synovial membranes and lung from 7 goats in New South Wales. These goats were clinically affected with the arthritic, neurologic, and pneumonic forms of CAEV infection either singly or in combination. CAEV antibody was detected by the gel immunodiffusion precipitin (GDP) test in 5 of the 7 goats. Serum samples from 2,708 goats, from 115 herds, were examined for CAEV antibody using the GDP test. Approximately one-third of the animals and 82% of the herds tested had CAEV antibody. The infection was common in all breeds of dairy goats with an indication of a significantly lower prevalence in the Saanen breed (24.4%) compared to Nubians, British Alpines and Toggenbergs (43.8%, 38.7% and 39.1% respectively). CAEV antibody was also demonstrated in 11 of 230 Angora goats. The infection was equally common in all age groups, with slightly higher prevalence in males (83 of 230, 36%) compared to females (648 of 2,232, 29%). Among seropositive animals 85% were clinically normal. Of 280 clinically affected goats tested only 42% had detectable antibody. One of 5 sheep that had been in contact with infected goats in one herd had CAEV serum antibody.  相似文献   

16.
An investigation was conducted to determine if depriving goat kids of colostrum and rearing them away from the herd would prevent transmission of caprine retrovirus infection. Twenty-four newborn goat kids were deprived of colostrum and reared on cow's milk away from their dams from an endemically infected goat herd. Twenty-three colostrum-deprived kids had no evidence of retrovirus infection at birth. One kid had sucked briefly and obtained some colostrum resulting in passive transfer of antibody but it did not develop evidence of infection. Nineteen showed no serological evidence of infection over the 370 days of the study. One colostrum-deprived, segregated goat was subsequently found to be infected and developed arthritis-synovitis. Three had doubtful positive response in one or 2 serological tests during the period but no evidence of infection in leucocyte co-cultures. Cells centrifuged from colostrum of infected goats were co-cultivated with foetal goat synovial membrane cultures. Caprine retrovirus was isolated from cells in the colostrum from the 3 goats examined.  相似文献   

17.
A serological survey for lentivirus infection was undertaken on a volunteer sample of 331 British goat herds. The prevalence of infected herds was 10.3 per cent and the prevalence of seropositive individual animals was 4.3 per cent. There was evidence of a geographical variation in the distribution of infection. Herds consuming pooled colostrum appeared to be at greater risk from infection. Approximately half the herds sampled had been established within the past six years. There was evidence of recently introduced infection in a relatively high proportion of infected herds.  相似文献   

18.
Clinical salmonellosis associated with Salmonella is increasingly reported in finishing swine. Since S. Typhimurium is often associated with these episodes and given that this serotype is among the most often reported in humans, we were interested to determine if various tissues and carcasses from animals coming from herds that were clinically affected were more likely to be contaminated by Salmonella compared to carcasses from animals raised in herds without any history of salmonellosis. Carcasses from animals from affected herds were significantly more contaminated by Salmonella while showing increased titers in antibodies directed against this bacterium. At the opposite, caecal contents and mesenteric lymph nodes from both groups of animals were similarly contaminated by Salmonella. In the second part of the study, we studied the persistence of the bacterium in various tissues after an experimental infection with S. Typhimurium. We found that, after the infection, Salmonella persisted for as many as 7 d in many extraintestinal tissues, while it was present in the feces of infected animals for all 14 d of the experiment. These findings indicated that carcasses from animals that experienced salmonellosis during their growth phase are more likely to be contaminated by this bacterium and that precautions must be taken in order to ensure that clinically affected animals should be kept on the farm for at least 7 d before being shipped for slaughter.  相似文献   

19.
The gamma interferon assay was evaluated for diagnosis of paratuberculosis in goats with special emphasis on false positive reactions. Four categories of herds were tested: (A) herds that had a history of paratuberculosis, had given positive Mycobacterium avium subsp. paratuberculosis fecal samples and were vaccinated against paratuberculosis; (B) herds that had been vaccinated but had never shown clinical signs of paratuberculosis nor given positive M. a. paratuberculosis fecal samples; and (C) non-vaccinated herds without paratuberculosis. To extend the analysis of samples from young goats free of paratuberculosis, animals less than 18 months of age from non-vaccinated herds without paratuberculosis, category D, were included. Heparinized blood was stimulated with purified protein derivate (PPD) from M. a. paratuberculosis for 24 h and plasma was assayed for the presence of gamma interferon. Results were recorded as the difference between OD values of PPD stimulated and control samples. Vaccinated animals from herds with paratuberculosis, category A, showed significant higher gamma interferon responses than animals from vaccinated herds without paratuberculosis, category B. In both these groups the responses were correlated to age with higher responses in younger animals. Some of the vaccinated animals in herds without paratuberculosis had a gamma interferon response lasting for several years, which demonstrate a long lasting interference with diagnostic testing in vaccinated goats. Only three of the 121 non-vaccinated animals free of paratuberculosis in category C had responses against PPD (corrected OD values at 0.2, 0.24 and 0.5), and none of the 255 young animals in category D had corrected OD values exceeding 0.2. This indicates that false positive reactions do not appear to the same extent in young goats as in young cattle. We conclude that the low responses of non-infected goats could make the gamma interferon assay useful in monitoring the paratuberculosis status of non-vaccinated herds. However, more information about the early gamma interferon responses of naturally infected goats and the presence of false negative samples are needed.  相似文献   

20.

Background

Toxoplasma gondii is a major problem for the sheep industry as it may cause reproduction problems. The importance of T. gondii in Norwegian goat herds is uncertain, but outbreaks of toxoplasmosis in dairy goat farms have been recorded. The aim of this study was to describe the prevalence of T. gondii infection in Norwegian dairy goats by using serology.

Findings

Goat serum originally collected as part of two nationwide surveillance and control programmes between 2002 and 2008 were examined for T. gondii antibodies by using direct agglutination test. In total, 55 of 73 herds (75%) had one or more serologically positive animals, while 377 of 2188 (17%) of the individual samples tested positive for T. gondii antibodies.

Conclusions

This is the first prevalence study of T. gondii infection in Norwegian goats. The results show that Norwegian goat herds are commonly exposed to T. gondii. Nevertheless, the majority of goat herds have a low prevalence of antibody positive animals, which make them vulnerable to infections with T. gondii during the gestation period.  相似文献   

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