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1.
Streptococcus suis infections in pigs in the Netherlands (Part I)   总被引：12，自引：0，他引：12  
Data are presented on the incidence of various streptococcal infections in pigs in the Netherlands. 314 Strains isolated in the course of routine post-mortem diagnosis were examined. The most frequently occurring streptococcus was S. subacidus (bio) type II which was isolated in 31.2% of the cases. S. suis type 2 (Serogroup R) and S. equisimilis (Serogroup C) constituted 16.2% and 13.7% of the isolates respectively. Besides meningitis, endocarditis and polyserositis S. suis type 2 infections may frequently be associated with pneumonia (42%). The biochemical profiles of the various S. suis and S. subacidus (bio) types are presented. The profile of both species is almost identical. It seems justified to use the name S. suis for strains with this characteristic profile and to abandon the name S. subacidus. Haemolysis does not appear to be a suitable characteristic to screen for S. subacidus/S. suis types. In comparing three serological methods for typing S. suis type 2, gel precipitation using Fuller's extract and slide agglutination give an almost 100% correlation. These two methods are recommended for serotyping.  相似文献   

2.
Summary

Since 1983 some pig breeding and fattening farms in the Netherlands have been faced with a considerable mortality in pigs due to Streptococcus suis type 2 infections. The most predominant clinical feature of S. suis type 2 infection is meningitis, although sudden deaths often occur. It was noted that some affected farms had imported breeding stock from the United Kingdom.

Tonsils of slaughter pigs were collected from herds with and without a history of S. suis type 2 infections. Bacteriological examination was done by using an elective‐selective medium. No significant difference was found in carrier rates of S. suis type 2 between clinically healthy and affected herds (38% vs. 45%).

A cohort study was carried out by regular bacteriological examination of tonsil biopsies on a farm with a high incidence of streptococcal meningitis. Twenty‐seven percent of the pigs were carriers of S. suis type 2 at nine weeks of age. Possible methods for disease control are discussed.  相似文献   

3.
Summary

Brucella suis biotype 1 was isolated from 13.1% of the pigs slaughtered in Kapuk Jakarta, West Java and from 15.09% of the pigs slaughtered in Surabaya, East Java. The prevalence of B. suis by means of the Rose Bengal Plate Test, was 22.3% for West Java and 14.9% for East Java. The Rose Bengal Plate Test detected more B. suis infected animals (73% of the infected animals) than did the Complement Fixation Test (41%) and the Serum Agglutination Test (54.5%).

The high infection rate is a potential health danger for the abattoir workers.  相似文献   

4.
Summary

Faecal samples from suckling piglets from 113 litters on 25 farms in the Netherlands were examined to study the prevalence of gastrointestinal parasites, in particular Strongyloides ransomi and Isospora suis. S. ransomi was not found but I. suis was demonstrated in 17 of the 25 farms and in 41 out of 77 litters of these farms (53%). No other parasites were found. On the basis of these results, a longitudinal study on the incidence and significance of I. suis was performed on 10 farms (5 litters/farm). I. suis was found on 9 out of 10 farms and in 56% of the litters. Farms differed in infection levels, measured as the numbers of patent litters, and in the onset of patency. Other parasites were only found in faecal samples from the sows and from farrowing pens. These were, in order of prevalence, Balantidium coli, Ascaris suum, Eimeria spinosa, E. debliecki and E. suis.  相似文献   

5.
Abstract

Several fungi have been isolated from the lesions of coho salmon Oncorhynchus kisutch that have saprolegniosis. Of these fungi, one that occurred frequently was identified as Saprolegnia parasitica strain H2 (=S. diclina type 1). A much rarer fungus was identified as S. diclina strain H3 (=S. diclina type 3). This article describes the pathogenicity of the isolates to coho salmon and the relationship of pathogenicity to the lengths of the isolates, hooked hairs.  相似文献   

6.
An avirulent, streptomycin-dependent (Str-D) mutant ofStreptococcus suis type 1/2 was produced and characterized by its antimicrobial susceptibility, growth kinetics, biochemical reactions and reversion rate. Homologous and heterologous vaccine trials in mice resulted in complete protection against challenge withS. suis types 1 and 1/2 and partial protection against challenge withS. suis type 2.Abbreviations Str-D streptomycin-dependent - CFU colony-forming units - PBS phosphate-buffered saline - IP intraperitoneal - LD50 the dose that results in 50% mortality  相似文献   

7.
Extract

Madam:– I wish to advise of the recent isolation of Streptococcus suis 1 and 2 from pigs in New Zealand. Type 1 was isolated from brain and joint swabs from a three-week-old piglet. The piglet had meningitis, was laterally recumbent, paddling and had arthritis with grossly swollen joints. Type 2 was isolated from tonsils collected from apparently normal bacon pigs slaughtered at a meat works. Isolates were confirmed as either Streptococcus suis type 1 or 2 on the basis of biochemical characteristics(4) and Lancefield precipitin tests using Sand R antisera as originally used by De Moor.(2)  相似文献   

8.
Extract

Salmonella cholerae suis (Salmonella suipestifer) is the cause of an infectious disease of weaner pigs which manifests itself as either a chronic enteritis or as an acute septicaemia in which the organism rapidly invades the body tissues and fluids. Although pigs of all ages can contract the disease, experience in New Zealand has shown that young pigs from eight to twelve weeks old are more susceptible. In 1947. experiments were commenced at Wallaceville to examine the possibility of protecting young pigs by inoculation with vaccines prepared from strains of S. cholerae suis isolated in this country. The purpose of this paper is to record and discuss the results of these experiments.  相似文献   

9.
Recent analyses of Streptococcus suis isolates using multilocus sequence typing (MLST) suggested the importance of sequence type (ST) 1 and ST27 complexes for animal hygiene and public health. In this study, to investigate whether pilus-associated genes in S. suis can be used as novel genetic markers for important clonal groups, we examined the correlation between STs and putative pilus-associated gene profiles in S. suis. Genomic searches using sequenced genomes and sequence data determined in several isolates revealed the presence of at least four distinct putative pilus gene clusters in S. suis (srtBCD, srtE, srtF, and srtG clusters). On the basis of the presence or absence of genes in the four clusters, 108 S. suis isolates from various origins were classified into 12 genotypes (genotypes A–L). Genotypes A and B, which possessed srtBCD plus srtF clusters and srtF plus srtG clusters, respectively, were the most common in isolates from diseased pigs and humans, and 29.9% and 59.8% of the isolates belonged to genotypes A and B, respectively. In contrast, only 4.8% and 28.6% of isolates from healthy carriers were genotypes A and B, respectively. MLST analysis showed the associations of genotypes A and B with ST1 and ST27 complexes, respectively. In addition, srtBCD and srtG clusters were preferentially distributed to ST1 and ST27 complex members, respectively. These results suggest that profiling of selected pilus-associated genes could be used as an easy screening method to monitor isolates important for S. suis infection.  相似文献   

10.
Four different experimental models for Streptococcus suis-induced disease were compared to find a model that closely mimics naturally occurring disease in conventional pigs. Fourteen, 2-week old pigs free of S. suis type 2 were used in 2 experiments. In experiment 1, 3 pigs were inoculated intravenously (IV) and 3 pigs intranasally (IN) with S. suis. Two out of 3 of the IV-inoculated pigs exhibited signs of severe central nervous system disease (CNS) and were euthanized. Streptococcus suis type 2 was isolated from whole blood, joints, and serosal surfaces of both pigs. No clinical signs and no growth of S. suis were detected in the IN-inoculated pigs. In experiment 2, 4 pigs were inoculated IV and another 4 were inoculated IN with the same isolate as in experiment 1. One hour before inoculation the IN-inoculated pigs were given 5 mL of 1% acetic acid intranasally (IN-AA). All the IV-inoculated pigs showed CNS disease and lameness, and 2 of the pigs became severely affected and were euthanized. All the IN-AA inoculated pigs exhibited roughened hair coats and 2 pigs developed severe CNS disease and were euthanized. Streptococcus suis was isolated from the joints and blood of 3 pigs in the IV-inoculated group. Streptococcus suis was isolated from blood of 2 pigs, meninges of 3 pigs, and joints of 1 pig in the IN-AA inoculated group. Natural exposure to S. suis most likely occurs by the intranasal route. The IN-AA model should serve as a good model for S. suis-induced disease, because the natural route of exposure is intranasal and the IN-AA model was effective in inducing disease that mimics what is observed in the field.  相似文献   

11.
Chlamydiae are frequently encountered Gram‐negative intracellular eubacteria that can cause clear manifestations or clinically asymptomatic disorders. C. suis and other chlamydia are primarily isolated in cases of reproductive disorders. This study was performed to estimate the impact of Chlamydia suis infection on reproduction in sows by analyzing reproduction rates and breeding parameters. The test was conducted on first generation (F1) pigs from Polish Landrace (PL) × Polish Large White (PLW). Sixty‐four herds were investigated and 500 vaginal swabs were collected. Isolation of DNA was carried out directly from the swabs. All samples were analyzed for Chlamydia suis by real‐time PCR with a locked nucleic acid (LNA)‐containing probe. To analyze the impact of chlamydia infection on reproductive parameters, evaluation questionnaires were used. Reproductive problems were found in 77.3% of the farms tested. The receiver operating characteristic curve indicated that in the farms with 10 up to 120 sows, there were higher reproductive problems with chlamydia infection than in smaller and bigger pig farms. The most common problems were estrus repetition, which was reported by 57.81% of the surveyed farms, and the birth of dead piglets, which was reported by 31.25% of the investigated pig farms. Abortions, which were reported by 28.12% of the surveyed farms, were the least common reproductive disorders.  相似文献   

12.
During the last 30 years, pig production in Uganda and neighbouring counties has increased markedly. Pigs are mainly kept as a source of income for small-scale farmers; however, the pig production is subject to several constraints, one of them being worm infections. A study was carried out in rural communities in Kabale District in the South Western part of Uganda in September and October 2007 in order to estimate the prevalence of gastrointestinal nematode parasites in pigs based on coprological examination. Fifty-six households were randomly selected and visited. Housing system and deworming history were recorded. Faeces was sampled from rectum of one to five pigs (age, 3–12 months) per household. A total of 106 pigs were examined coprologically of which 91% excreted nematode eggs. The following prevalences of nematode eggs were recorded: strongyles (89%), Ascaris suum (40%), Trichuris suis (17%) and spiruroid eggs (48%). On household level, rearing pigs on slatted floors in pens significantly reduced the faecal egg excretion of strongyle eggs with almost 80% (p = 0.010) and a significant interaction between floor type and anthelmintic treatment was found for spiruroids (p = 0.037). Fifteen T. suis egg positive pigs were selected for post-mortem examination of the gastrointestinal tract. The post-mortem examinations revealed that 93% pigs were infected with Oesophagostomum spp. (worm burden, min–max 10–2,180), 73% with A. suum (1–36), 67% with T. suis (6–58), and 20% with Hyostrongylus rubidus (worms not quantified). In general, nematode infections were widespread and polyparasitism common in pigs in Uganda. However, worm burdens were moderate which may be related to recent deworming or to the practice of rearing pigs on slatted floors in wooden elevated pens.  相似文献   

13.
A butcher with chronic dermatitis presented with a second episode of Streptococcus suis meningitis, 8 years after the first episode. To distinguish between reinfection and persistent carriage, we compared the two S. suis isolates using whole genome sequencing. We investigated whole genome sequences of the S. suis isolates by means of substitution rates and population structure of closely related strains in addition to available clinical information. Genome‐wide analyses revealed an inserted region consisting of 12 genes in the first isolate and the calculated substitution rate between the isolates suggested infections were caused by highly similar, but unrelated strains. Continuous occupational exposure likely resulted in reinfection with S. suis in a butcher.  相似文献   

14.
Streptococcus suis is an important pathogen in the swine industry. This study is the first to report on the antimicrobial susceptibility of S. suis isolated from clinically healthy pigs in Brazil; the fourth major pork producer in the world. The antimicrobial susceptibility of 260 strains was determined by disc diffusion method. Strains were commonly susceptible to ceftiofur, cephalexin, chloramphenicol, and florfenicol, with more than 80% of the strains being susceptible to these antimicrobials. A high frequency of resistance to some of the antimicrobial agents was demonstrated, with resistance being most common to sulfa-trimethoprim (100%), tetracycline (97.69%), clindamycin (84.61%), norfloxacin (76.92%), and ciprofloxacin (61.15%). A high percentage of multidrug resistant strains (99.61%) were also found. The results of this study indicate that ceftiofur, cephalexin, and florfenicol are the antimicrobials of choice for empirical control of the infections caused by S. suis.  相似文献   

15.
Abstract

Saprolegnia sp. isolated from channel catfish Ictalurus punctatus grew slower than S. parasitica on cornmeal agar (CMA). Oogonia in Saprolegnia sp. appeared frequently, whereas oogonia were rarely seen in S. parasitica on CMA. In experimental exposures of injured channel catfish to fungal spores, infections were apparent after 3–4 d, but were most common after 7–9 d. Multiple lesions were usually seen in naturally infected fish, whereas a single lesion appeared at the injured site of experimentally infected fish. No obvious differences were found between lesions caused by S. parasitica and those caused by Saprolegnia sp. Most of the epidermal cells in fungusinfected lesions were necrotic. In some lesions, the epidermis was completely sloughed and the dermis was exposed. Both Saprolegnia parasitica and Saprolegnia sp. penetrated the dermis, causing damage to fibroblasts and collagen lamellae.  相似文献   

16.
Streptococcus suis is an important pathogen in the swine industry. This article is the first to report the occurrence, risk factors, serotype distribution, and antimicrobial susceptibility of S. suis recovered from employees and environmental samples of swine slaughterhouses in Brazil. Tonsillar swabs from all 139 pig-slaughtering employees and 261 environmental swabs were collected for detection of S. suis and serotyping by monoplex and multiplex polymerase chain reaction, respectively. Antimicrobial susceptibility was determined by the disk-diffusion method. Although S. suis was not detected in any of the tested employees, it was isolated from 25% of the environmental samples. Significant differences (P < 0.05) in the occurrence of S. suis were observed between slaughterhouses and between areas of low, medium, and high risk. The most frequent serotypes were 4 and 29, each accounting for 12% of the isolates, followed by 5, 12, 21, and 31, each accounting for 6%. High rates of susceptibility to the antimicrobials doxycycline (100%), ceftiofur (94%), ampicillin (81%), and cephalexin (75%) were observed. However, multidrug resistance was observed in all the isolates. Because S. suis is present in the environment of swine slaughterhouses, on carcasses and knives, as well as on the hands of employees in all areas, all employees are at risk of infection.  相似文献   

17.
Summary

The prevalence of S. bovis in the intestinal tract of healthy racing pigeons was determined. Crop and cloaca swab samples obtained from 810 pigeons from 14 different lofts and from 122 pigeons that were presented for routine health control were examined for the presence of S. bovis. Pooled faecal samples were also obtained from pigeons in 82 different pigeon lofts. S. bovis was isolated from crop or cloaca samples of approximately 40 % of pigeons of all ages by direct culture and from 80 % of the pooled faecal samples by enrichment culture.

In a longitudinal study, crop and cloaca samples were collected every 3 months from pigeons in seven different pigeon lofts. The prevalence of S. bovis in these pigeons ranged from 0 to 100 %. The carriage rate was not related to the season or to the age of the pigeons.

The prevalence of S. bovis in organ lesions of pigeons examined at necropsy was investigated over a 35‐month period. S. bovis was isolated from 10 % of the birds examined. The incidence of S. bovis septicaemia was significantly higher in January to August than in September to December. It was concluded that S. bovis is an opportunistic pathogenic agent in pigeons.  相似文献   

18.
The aim of this study was to compare, by randomly amplified polymorphic DNA (RAPD), the diversity of Streptococcus suis serotypes 1/2 and 2 isolates recovered at slaughter houses from the tonsils of clinically healthy pigs. The pigs belonged to herds with or without clinical signs of S. suis disease.

Overall, a low diversity was observed among isolates of serotype 1/2. A representative isolate recovered from a diseased animal presented a relatively high similarity (85%), with most isolates recovered from carrier pigs, from herds either with or without clinical signs of S. suis disease. For serotype 2 isolates, a relatively high degree of heterogeneity was observed in the whole population. Two subpopulations were observed for serotype 2 isolates, which arose from herds with clinical signs. Interestingly, the representative isolate coming from the diseased pig was included in a small closed cluster, with 2 isolates recovered from carrier pigs belonging to the same herd. On the other hand, most of the S. suis serotype 2 isolates originating from herds with no history of S. suis disease, were closely related (90% similarity). Furthermore, they presented different RAPD patterns from those originating from animals from the herd presenting S. suis clinical signs due to this serotype. Results suggest that, in the herds studied, clinical manifestations due to serotype 2 are probably related to the virulence of a specific isolate. Conversely, for the herd affected with serotype 1/2, clinical manifestations of the disease were more likely to be the result of inherent herd factors than the virulence of the specific isolate.

  相似文献   

19.
Summary

Bacteriological examination of hatchery waste eggs, identification of the isolated bacteria, and susceptibility testing against seven antimicrobial agents were used in an attempt to establish a rational basis for reducing bacterial infections in newly hatched chicks.

Chloramphenicol at 1000 ppm was selected as the antibiotic for preliminary dipping trials and 0.45% iodophore (Wescodyne) was added for later trials. The control treatment consisted of formaldehyde fumigation. The following conclusions can be drawn:

(1) Hatchery waste eggs are highly contaminated (69.1%) and enterobacteriaceae predominate (26.6%).

(2) Chloramphenicol is the most effective antimicrobial tested.

(3) Dip treatments with either chloramphenicol alone or chloramphenicol plus Wescodyne result in a reduced percentage of abnormal navels (8.4% and 10.4%), as compared with 21.9% for the control treatment.

(4) Hatchability of either group of dipped eggs is reduced in comparison with fumigated eggs.

(5) Dip treatment with chloramphenicol plus Wescodyne significantly reduces the anal carrier rates for Escherichia coli, Pseudomonas aeruginosa, Salmonella spp., and Staphylococcus aureus. This treatment reduces the incidence of bacterial infection in abnormal navels to zero.  相似文献   

20.
Abstract

Epizootics attributable to erythrocyytc inclusion body syndrome (EIBS) occurred among populations of coho salmon Oncorhynchus kisutch cultured in seawater in Japan. Onset of the disease was correlated with water temperatures declining to below 10°C. Symptoms of EIBS were severe anemia with hematocrits of less than 20% and corresponding changes in erythrocyte counts, hemoglobin concentration, and mean corpuscular hemoglobin concentration. Erythrocytes had characteristic inclusion bodies that contained enveloped viral particles with a diameter of approximately 77 nm. The disease was reproduced in artificially induced infections.  相似文献   

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