Biomedical subjects

E F Kaleta

Publications and source records attributed to E F Kaleta.

At least 19 recordsLinked to original sources

PubMed2006

Determination of the inhibitory concentration 50% (IC50) of four selected drugs (chlortetracycline, doxycycline, enrofloxacin and difloxacin) that reduce in vitro the multiplication of Chlamydophila psittaci.

A total of 18 chlamydial isolates from various psittacine birds, one isolate from a domestic pigeon and one isolate from a Pekin duck were isolated in continuous Buffalo Green Monkey (BGM) kidney cell cultures. All 20 isolates were identified by nested multiplex polymerase chain reaction as Chlamydophila psittaci. These isolates were multiplied to high titres and subsequently tested for in vitro sensitivity against two tetracyclines (chlortetracycline and doxycycline) and two quinolones (enrofloxacin and difloxacin) at concentrations of 0.0, 0.25, 0.50, 1.00, and 10.00 microg/ml. Replication of chlamydia in BGM cell cultures is assayed on the basis of formation of intracytoplasmic inclusions that are visualized by Giménez staining. All isolates, although to variable degrees, are sensitive to all four drugs. The number of chlamydial inclusions decreases gradually over a broad range of increasing concentrations of the drugs. The variation in the number of inclusions between isolates is remarkably high for chlortetracycline less for doxycycline and minimal for both fluoroquinolones, the enrofloxacin and difloxacin. The decline in numbers of inclusions is highly dose-dependend and the observed reduction stretches over a wide range of drug dilutions. Therefore, it is proposed to calculate drug sensitivity values in terms of inhibitory concentration 50%, (IC5). Its calculation includes all tested drug dilutions instead of the hitherto more common minimal inhibitory concentration, MIC, which is based on results of serial dilution tests for cell-free growing bacteria. Using a logistic regression model for the calculation of the inhibitory concentration 50% of all 20 chlamydial isolates, the IC50 is 0.807 microg/ml for tetracycline, 0.497 microg/ml for doxycycline, 0.180 microg/ml for enrofloxacin and 0.168 microg/ml for difloxacin. Complete prevention of inclusion formation was already seen for enrofloxacin at a concentration of 1.0 microg/ml in 12 out of 20 and for difloxacin in 5 out of 20 isolates whereas more than 10 microg/mI chlortetracycline is needed in 15 out of 20 isolates and for doxycycline 9 out of 20 isolates yielded inclusions at 10 microg/ml.

Animals↗

PubMed2005

PCR-based detection of genes encoding virulence determinants in Staphylococcus aureus from birds.

The present study was designed to comparatively investigate 19 Staphylococcus aureus strains isolated from specimens of 19 different birds during routine microbiological diagnostics. The S. aureus strains were characterized genotypically by polymerase chain reaction (PCR) amplification using 62 different oligonucleotide primers amplifying genes encoding staphylococcal cell surface proteins, exoproteins and two classes of the accessory gene regulator agr. All 19 investigated S. aureus were positive for the gene segment encoding a S. aureus-specific part of the 23S rRNA, the genes encoding thermostable nuclease (nuc), clumping factor (clfA) and coagulase (coa) and the gene segments encoding the Xr-repetitive region and the immunoglobulin G (IgG)-binding region of protein A (spa). In addition, all tested strains were positive for the genes hla and fnbA and negative for the genes seb, sec, sed, see, sej, tst, eta and etb. The remaining genes, including sbi, hlb, fnbB, ebpS, cna (domains A and B), cap5, cap8, set1, agr class I, agr class II, sea, seg, seh and sei were detected in a variable number of isolates. The presented data give an overview on the distribution of virulence determinants of S. aureus strains isolated from birds. This might be useful to understand the role of these virulence determinants in bird infections.

Animals↗

PubMed2005

Mycological examinations on the fungal flora of the chicken comb.

A total of 500 combs of adult chickens from two different locations in Germany (Hessen and Schleswig-Holstein) were clinically and mycologically examined. The chickens came from three battery cages (n = 79), one voliere system (n=32), six flocks maintained on deep litter (n = 69) and 12 flocks kept on free outdoor range (n=320). Twenty-two of the 500 chicken combs (4.4%) were found to have clinical signs: only non-specific lesions neither typical of mycosis nor of avian pox such as desquamation with crust formation, yellow to brown or black dyschromic changes, alopecia in the surrounding area and moist inflammation. Only seven of the 22 clinically altered combs showed a positive mycological result; the non-pathogenic and geophilic Trichophyton terrestre in one case and non-pathogenic yeast in six cases. The following fungi were seen in the different housing systems: 13 dermatophytes (2.6% of 500 samples): 12 x T. terrestre, 1 x Trichophyton mentagrophytes, 11 isolates of Chrysosporium georgiae (2.2% of 500 samples) and 149 isolates of yeasts (29.8%): Malassezia sympodialis: n = 52, Kloeckera apiculata: n = 33, Trichosporon capitatum (syn. Geotrichum capitatum): n = 23, Trichosporon cutaneum/Trichosporon mucoides: n = 12, Trichosporon inkin (syn. Sarcinosporon inkin): n = 8 and Candida spp.: n = 21, including pathogenic or possibly pathogenic species: Candida albicans: n = 3, Candida famata: n = 4, Candida guilliermondii: n = 3, Candida lipolytica: n = 3, Candida dattila: n = 2 and one isolate each of Candida glabrata, Candida parapsilosis, Candida aaseri, Candida catenulata sive brumpti, Candida fructus and Candida kefyr sive pseudotropicalis. There is no stringent correlation between the clinical symptoms diagnosed on the chicken combs and the species of yeasts isolated. The causative agent of favus in chickens, Trichophyton gallinae, and the saprophytic yeast in pigeons, Cr. neoformans were not isolated. The most frequently isolated yeasts M. sympodialis and Kloeckera apiculata are suggested to be classified as members of the resident flora of the chicken comb.

Animals↗

PubMed2005

A retrospective description of a highly pathogenic avian influenza A virus (H7N1/Carduelis/Germany/72) in a free-living siskin (Carduelis spinus Linnaeus, 1758) and its accidental transmission to yellow canaries (Serinus canaria Linnaeus, 1758).

A haemagglutinating virus was isolated in summer 1972 from a single free-living siskin (Carduelis spinus Linnaeus, 1758) in embryonated chicken eggs. Additional cases of morbidity or mortality were not observed in the area were the sick siskin was found. The virus was characterized as an avian influenza A virus of the subtype H7N1 and designated H7N1/Carduelis/Germany/72. The virus induced following experimental inoculation of chicken embryos a high rate mortality (mean death time approximately 24 hours), formed plaques in chicken embryo fibroblast cultures without addition of trypsin and has an intracerebral pathogenicity index (ICPI) of 1.80. Therefore, this virus is considered as a highly pathogenic avian influenza A virus. Canaries (Serinus canarius Linnaeus, 1758), that were housed in the same room with the siskin were accidentially exposed by contact to the sick siskin which resulted in virus transmission followed by conjunctivitis, apathy, anorexia and a high rate mortality.

Animals↗

PubMed2005

Avian influenza A viruses in birds --an ecological, ornithological and virological view.

Avian influenza A viruses (AIV) are the causative agents of the presently most important poultry disease. Ten countries in Asia and several other countries in Eastern Europe suffer high losses from the lethal effects of these viruses of the H5N1 subtype. AIV of other subtypes cause in additional countries severe losses. The threat to health and well-being of the avifauna, domestic poultry and possibly mammals including humans are worldwide of major concern. The European Union reacted with a complete import ban on untreated meat, eggs, poultry products as well as free-living and pet birds. Extensive surveillance of free-living birds and domestic poultry that is maintained in free-range and close to open waters were initiated in an attempt to gather information on the current status of infection with these viruses and to target appropriate countermeasures for the protection of domestic poultry (in-house keeping) and to safeguard food production for humans. Since the monitoring of free-living birds is labour-intensive, costly, and time-consuming, only birds should be included in the monitoring programme that harboured in the past most if not all influenza A viruses. The birds of the order Anatiformes, family Anatidae, subfamilies Anserinae and Anatinae, provided 65.9 % of all avian AIV isolates. The cosmopolitan Common Mallard (Anas platyrhynchos) is the dominant species with the highest rate of isolations among all bird species. Second in frequency is the North-American Blue-winged Teal (Spatula discors). Consequently, free-living anatiform birds of the genera Anas and Spatula should comprise the main focus for the collection of cloacal and pharyngeal swabs. With the likely exception of the most recent H5N1 viruses, signs of disease were not recorded in AIV infected anatiform birds. AIV isolations were definitely less frequently obtained from birds of the orders Phasianiformes (including domestic chickens and turkeys), Charadriiformes (plovers and lapwings), Lariformes (gulls), Columbiformes (pigeons) and Psittaciformes (psittacines) and need less attention in sampling efforts. This review presents also data on taxonomy and most suitable means for isolation and typing of haemagglutinating viruses. The different frequencies of the detection of 16 haemagglutinin (HA) subtypes and 9 subtypes of neuraminidase (NA) surface antigens are composed on the basis of extensive literature retrievals. Both antigens occure in isolates at different frequencies. Only 103 of all 144 possible HA x NA combinations were described so far. The AIV that contain the HA subtypes H3, H4, H6 are most frequently isolated whereas the AIV of the subtypes H5 and H7 were less frequently encountered. All other HAs are rather rare. AIV that possess the NA of the subtypes N2, N1, N8 and N3 are frequent and all other NAs are rarely detected.

Animals↗

PubMed2004

[Disinfectant tests at 20 and 10 degrees C to determine the virucidal activity against circoviruses].

To evaluate virucidal activity against porcine circovirus type 2 (PCV2), four disinfectants were tested under laboratory conditions. As basis to perform the testing the "Guidelines for testing chemical disinfectants" of the German Veterinary Association (DVG-guidelines) were applied. For simulation of field conditions, the tests were carried out in virus carrier tests, at 20 and 10 degrees C, and under protein load (40% foetal calf serum (FCS) in virus suspension). For disinfection of PCV2 at 20 degrees C an exposure time of 120 min in 2% Disinfectant 1 (20% glutaraldehyde, 12% 2-propenal, polymer with formaldehyde) or Disinfectant 2 (55% formic acid, 7% glyoxylic acid) was necessary. 1% of Disinfectant 3 (Component 1: Potassium peroxomonosulphate. Component 2: Active detergents) disinfected PCV2 on carriers within 180 min. After a reaction time of 120 min with 1% and 60 min with 2% Disinfectant 4 (21% glutaraldehyde, 17% formaldehyde) there could not be detected any virus. Reduction on effectivity through temperature reduction to 10 degrees C were more significant for aldehyde containing preparations Disinfectant 1 and Disinfectant 4 than for Disinfectant 2 and Disinfectant 3. These losses on effectivity could be corrected through extension of exposure time or increase of concentration.

Animals↗

PubMed2004

Review of the literature on avian influenza A viruses in pigeons and experimental studies on the susceptibility of domestic pigeons to influenza A viruses of the haemagglutinin subtype H7.

The scientific literature of the past century is reviewed on fowl plague (presently termed highly pathogenic avian influenza, HPAI) in pigeons. HPAI viruses cause epidemic disease outbreaks with high rates of losses in many avian species, particularily in chickens and turkeys. Also susceptible to disease are quails, guinea fowl, ducks, geese, ostriches, passerine birds, and birds of prey whereas conflicting reports on the susceptibility of the domestic pigeon exist. Based on literature reports and on own experiments, and applying as criteria for judgements clinically overt forms of disease, virus multiplication plus shedding and seroconversion, it is concluded that domestic pigeons are only partially susceptible to influenza A viruses of the haemagglutinin subtype H7. Infection of pigeons with H7 viruses results only in some of them in signs, virus shedding and seroconversion. Using the same criteria, pigeons appear to be even less susceptible to infection with influenza A viruses of the H5 subtype. Only one of five publications describe in 1/19 pigeons exposed to H5 influenza A virus depression one day before death, and only 2/19 multiplied and excreted virus, and 1/19 developed circulating antibodies. Consequently, pigeons play only a minor role in the epidemiology of H5 influenza viruses. In contrast, following infection with influenza A virus of the subtype H7 clinical signs in pigeons consist of conjunctivitis, tremor, paresis of wings and legs, and wet droppings. H7-infected pigeons multiply and excrete H7 viruses and develop circulating antibodies. Albeit of the status of infection, free-flying domestic pigeons can act as mechanical vectors and vehicles for long-distance transmission of any influenza A virus if plumage or feet were contaminated.

Animals↗

PubMed2003

Investigation of several selected adjuvants regarding their efficacy and side effects for the production of a vaccine for parakeets to prevent a disease caused by a paramyxovirus type 3.

The infection with paramyxovirus type 3 (PMV-3) of parakeets can lead to severe illness in small psittacines (Neophema spp. and other parakeets) as well as in passerines (finches). The disease is characterized by acute or chronical pancreatitis and central nervous symptoms, such as torticollis as well as walking in circles and by high mortality rates in the affected flocks. As there is no licensed vaccine for psittacines available to prevent this disease. The aim of the following study was to find a suitable vaccine formulation for parakeets with inactivated PMV-3 and a well-tolerated and effective adjuvant. Seven adjuvants have been examined in ovo and in vivo regarding their efficacy and side effects. In these investigations, the classical Freund's complete Adjuvant (FCA) and Freund's incomplete Adjuvant (FICA) and Alhydrogel, but also the more recent developments TiterMax Gold, Specol, Gerbu Adjuvant 100, and Diluvac Forte have been used. Regarding its efficacy and side effects, the vaccine formulation "PMV-3/Specol" has been evaluated positively and can be recommended for the production of a PMV-3 vaccine for parakeets.

Adjuvants, Immunologic↗

PubMed2003

Evaluation of virucidal activity of three commercial disinfectants and formic acid using bovine enterovirus type 1 (ECBO virus), mammalian orthoreovirus type 1 and bovine adenovirus type 1.

A modified version of the test method of the Comité Européen de Normalisation (CEN) was developed using formic acid and three commercial disinfectants to evaluate virucidal activity against three non-enveloped viruses, bovine enterovirus type 1 (ECBO virus), mammalian orthoreovirus type 1 and bovine adenovirus type 1 (BAV 1). Determination of the effects of temperature was carried out at 20 and 10 degrees C. All tests with protein load used bovine serum albumin (BSA) and yeast extract. The investigations were performed in suspension tests and in carrier tests using poplar wood virus carriers. The carrier tests showed that ECBO virus could be inactivated at 20 degrees C with 1% formic acid within a 60 min reaction time. For disinfection of ECBO virus at 10 degrees C within 60 min, a 2% concentration of formic acid was necessary. Formic acid was ineffective against reovirus and bovine adenovirus and cannot be recommended as a reference disinfectant. Inactivation of ECBO virus and adenovirus type 1 using a disinfectant containing aldehydes and alcohols could be achieved, but only at room temperature. The disinfection of reovirus type 1 at room temperature with this product was possible without a protein load. This disinfectant exhibited disinfection ability at 10 degrees C at a concentration of more than 2% or with a longer exposure time. A disinfectant containing aldehydes was effective at room temperature but its effect was reduced in the presence of organic matter. Inactivation at 10 degrees C was found only against adenovirus. The fourth disinfectant, which contained peroxiacetic acid, inactivated all test viruses at a concentration of 0.5% within 15 min independent of temperature and protein load.

Animals↗

PubMed2003

Investigations on suitability of different materials for carriers to be used for virucidal testing of chemical disinfectants in the veterinary field.

Various materials with rough surfaces were tested to determine their suitability for virus carrier tests designed to evaluate virucidal activity of chemical disinfectants. A non-enveloped RNA virus, bovine enterovirus type 1, strain LCR 4 [entero cytopathogenic bovine orphan virus (ECBO)] and an enveloped RNA virus, paramyxovirus type 1 [Newcastle disease virus (NDV), strain Montana] served as test viruses. Experiments with ECBO virus were carried out in four sets, and those with NDV in three sets. In the first set we used poplar wood, frosted glass slides and Sartorius membrane filters. The second set comprised of poplar wood, frosted glass slides, polyamide filters, and cellulose nitrate filters and, in the third set, glass fibre filters and glass fibre pre-filters were added. The fourth test included poplar wood, frosted glass slides, and polyethersulphone ultra filters. Because of their extremely low levels of virus recovery, glass, polyamide, cellulose nitrate and glass fibre filter, glass fibre pre-filter, and polyethersulphone ultra filters are not suitable for sufficient recovery of ECBO virus. Only poplar wood carriers allowed sufficient recovery rates of ECBO virus. In the first and second set of tests, NDV could be sufficiently recovered from poplar wood, glass slides, and polyamide filter. In the third set, the virus recovery from polyamide filter was very low. Poplar wood carrier is recommended as a reliable carrier for the tests with both viruses, but methods for virus recovery must be improved, e.g. by more vigorous and longer shaking or optimizing the ultrasonic treatment.

Animals↗

PubMed2003

Occurrence of genotypes IV, V, VI and VIIa in Newcastle disease outbreaks in Germany between 1939 and 1995.

Forty-five velogenic Newcastle disease virus strains isolated in Germany between 1939 and 1995 were analysed by restriction enzyme digestion and sequencing to shed light on the relationships of past epizootics. Viruses derived from the period prior to 1970 belonged to a clade (IVea) of genotype IV comprising the earliest isolates from Europe, and could be isolated until the late seventies from poultry. Essex'70-like viruses, the prototype of genotype V, were already present at the beginning of the 1970-74 epizootic and in sporadic cases thereafter, indicating that these Newcastle disease outbreaks started in Western Europe. A genotype VI (subtype VIc) isolate was obtained in the early 1980s from a single outbreak in poultry. Outbreaks between 1993-95 were again part of a Western European epizootic caused by a genotype VIIa virus that was prevalent in the Far East.

Animals↗

PubMed2003

Avian host range of Chlamydophila spp. based on isolation, antigen detection and serology.

Published reports and our own diagnostic data on the avian host range of avian Chlamydophila spp. are presented in an attempt to provide evidence for the large number of bird species that have been naturally infected with chlamydia. The term 'chlamydia-positive' is based on either isolation of the organism and antigen detection or on serological detection of circulating antibodies. The list of chlamydia-positive birds contains the six major domestic species (chicken, turkey, Pekin duck, Muscovy duck, goose, and pigeon), the three minor domestic species (Japanese quail, bobwhite quail, and peafowl) and a total of 460 free-living or pet bird species in 30 orders. The order Psittaciformes contains by far the most (153 of 342; 45%) chlamydia-positive bird species. More than 20% of all species per order are positive for chlamydia in the orders Lariformes (gulls, 26 of 92 species; 28%), Alciformes (alks, six of 23 species; 26%), Sphenisciformes (penguins, four of 16 species; 25%), and Anseriformes (ducks and geese, 33 of 157 species; 21%). Only 5% of all bird species (14 of 259 species) in the order Phasianiformes (gallinaceus birds) are chlamydia-positive. The different percentages of chlamydia-positive bird species reflect: (i) a high rate of investigations (e.g. of domestic birds) compared with infrequent testing (e.g. of Charadriiformes or Cuculiformes), (ii) frequent zoonotic implications (e.g. psittacine and columbiform birds), and (iii) an assumed high susceptibility to infection and subsequent seroconversion (e.g. waterfowl).

Animals↗

PubMed2003

[Disinfection of caliciviruses at 20 and 10 degrees C].

Five disinfectants, Venno FF super, Venno Vet 1 super, Venno Oxygen, M&Enno-Veterinär B neu und Neopredisan 135-1, were tested to evaluate their efficacy against caliciviruses at 20 and 10 degrees C. As model test virus served feline calicivirus type F9 (FCV F9). All disinfectants were tested according to Guidelines of the German Veterinary Association (DVG). The investigations were performed in suspension tests and germ carrier tests. The suspension tests were carried out without and with protein load. As protein was used foetal calf serum at the concentration of 40%. Venno FF super showed less protein dependence, however a considerable temperature dependence. This matter can be corrected by increase of concentration on 2%. Venno Vet 1 super was without protein especially effective. The losses on the effectiveness through low temperature and protein load can be annulled also here by increase of concentration. Venno Oxygen was more effective in the comparison to that here named both preparations. The effects of temperature can be corrected by extension of reaction time. The most effective preparation was M&Enno Veterinär B neu. The disinfection occurred at 20 degrees C with 0.5% solution within 120 min and at 10 degrees C with 1.0% solution within 60 min. The fifth disinfectant Neopredisan was in suspension tests without protein load and carrier tests with gauze at 20 and 10 degrees C relative convincing but in germ carrier tests with poplar wood, no complete disinfection could be achieved within tested concentrations and reaction times.

Animals↗

PubMed2003

Undesirable reactions of domestic pigeons to vaccination against paramyxovirus type 1.

Subcutaneous vaccination of fancy and racing pigeons with inactivated oil-based vaccines protects against all clinical manifestations caused by the Paramyxovirus type 1. Correct application of the vaccine may occasionally result in the development of granulomas or abscess-like lesions on the site of vaccine application. Although protected against disease as proven by challenge experiments, a variable proportion of vaccinated pigeons do not react with the formation of detectable serum antibodies. The pathogenesis of granuloma and abscess-like lesion developments and the failure to form humoral antibodies are presently not understood. Questions relating to legal liability of vaccinating veterinarians are briefly discussed.

Abscess↗

PubMed2002

Herpesviral, but no papovaviral sequences, are detected in cloacal papillomas of parrots.

Internal papillomatosis of parrots (IPP) is a tumour disease with unknown etiology, characterised by progressive development of papillomas in the oral and cloacal mucosa. Based on epidemiologic data, infectious agents, particularly DNA tumour viruses, are considered to be involved. In this study, cloacal papillomas were investigated by PCR for the presence of herpesvirus, papillomavirus and avian polyomavirus genomes, respectively. Using consensus and specific primers, 5 out of 12 papillomas were tested positive for herpesvirus; all papillomas were tested negative for papillomavirus and avian polyomavirus. The DNA sequence of one of the PCR products showed 86.5% homology to the corresponding region of the psittacine herpesvirus 1 DNA polymerase gene. Using a PCR with primers based on this sequence, additional 4 papillomas were tested positive. By in situ hybridisation, herpesviral sequences were detected in epithelial cells of the papilloma, but not in surrounding tissues. As 75% of the tumours proved to be positive, these data suggest an involvement of a herpesvirus in the etiology of IPP; the distinct role, however, needs to be investigated.

Animals↗

PubMed2002

Seroprevalence of avian paramyxovirus 1, 2, and 3 in captive and free-living birds of prey in Spain (preliminary results): implications for management of wild and captive populations.

Since December 1997, 700 blood plasma samples from 31 different species of captive and free-living birds of prey from Spain were analyzed by hemagglutination inhibition (HI) test for the presence of antibodies to avian paramyxovirus (aPMV) 1,2, and 3. Out of 700 birds, 120 tested positive for aPMV-1, 10 birds had antibodies to aPMV-2, and 4 birds tested positive against aPMV-3. Prevalence of antibodies against aPMV-1 was significantly higher in captive than in free-living birds of prey and in Falconiformes than in Strigidae and Accipitridae. Infection or exposure in captive birds may be due to the use of avian-derived food in rehabilitation and captive-breeding centers. This may be of concern at the time of reintroduction of these birds into free-living populations.

Animals↗

PubMed2002

Pathology of avian pox in wild red-legged partridges (Alectoris rufa) in Spain.

The diagnosis and pathology of an avian pox outbreak in free-living red-legged partridges in Cádiz, Southern Spain, is described. Diagnosis of the disease was based on histopathology, ultrastructural examination of, and virus isolation from lesions of necropsied animals. Lesions were present mainly in juvenile partridges (41%), and were observed primarily on the dorsal part of the digits or on the hock joint. The lesions ranged from small wartlike nodules to large tumor-like lesions. The presence of acute lesions of any grade as opposed to absence of lesions or healed lesions adversely affected body condition of the partridges (P <.01). Further investigations on the epidemiology of the disease and on the relation of the isolated strains to other avian poxviruses are under way.

Animals↗

PubMed2002

Foot-and-mouth disease: susceptibility of domestic poultry and free-living birds to infection and to disease--a review of the historical and current literature concerning the role of birds in spread of foot-and-mouth disease viruses.

Ruminants and pigs are the dominant natural hosts of food-and-mouth disease (FMD) viruses. Approximately 70 additional mammalian species are found to be susceptible under natural or experimental conditions. Reptilia, amphibia, and fish are probably naturally resistant to infection. According to the reviewed literature, domestic birds (chickens, turkeys, guinea fowl, ducks and geese) have been experimentally infected with some strains of FMD viruses and may develop lesions suggestive of FMD such as vesicular lesions on the comb, wattles, eye lids, and feet. Since chickens are to some extent coprophagous, chickens get infected by ingestion of virus under conditions of natural exposure or their plumage gets contaminated in an infectious environment. Thus, domestic birds kept in free-run systems may serve as virus vectors for short distances. Free-living birds, especially starlings (Sturnus vulgaris), sea gulls (Larus canus), house-sparrows (Passer domesticus) have been successfully experimentally infected and developed vesicular lesions on the skin and mucosal membranes of the mouth. During epizootics of FMD the plumage of these free-living birds can be contaminated with FMD viruses and the virus is spread over long distances during migration periods in spring and autumn. Thus migrating birds may assume an active role in long distance dissemination of FMD viruses.

Animals↗