Proliferative responses of lymphocytes to mitogens in the gray, short-tailed opossum, Monodelphis domestica.     

C M Brozek  E W Kaleta  D F Kusewitt  R D Ley 《Veterinary immunology and immunopathology》1992,31(1-2):11-19

A South American opossum (Monodelphis domestica) is a model animal for studies on the health effects of exposure to ultraviolet radiation (UVR). As part of a broad evaluation of immune function in this animal, we have tested in vitro mitogenic responses using whole blood cultures. Lymphocytes proliferated in the presence of phytohemagglutinin (PHA), concanavalin A (Con A), and pokeweed mitogen (PWM), but were unresponsive to bacterial lipopolysaccharide (LPS).  相似文献   

Polyomavirus infection in budgerigars (Melopsittacus undulatus): clinical and aetiological studies   总被引：1，自引：0，他引：1  

M E Krautwald  H Müller  E F Kaleta 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1989,36(6):459-467

In order to get insight into the aetiology of French Moult (FM) and Budgerigar Fledgling Disease (BFD), and to determine relationships between the two diseases, 298 budgerigars from 49 different breeding flocks were examined. From all birds with BFD and from several birds with FM, viruses were isolated which produced characteristic cytopathic changes in chicken embryo fibroblasts. They were insensitive to chloroform treatment, and their replication was inhibited in the presence of 5-iododeoxyuridine. One of these isolates, from a bird exhibiting clinical signs of BFD, was determined by biochemical and biophysical methods to be a polyomavirus (BFDV). Nestling budgerigars 3 to 10 days of age, were inoculated with this BFDV isolate. They developed an acute systemic disease with high mortality rates, similar to naturally occurring infections. In this regard, BFDV differs markedly from all the other polyomaviruses known until now which only cause clinically asymptomatic, persistent infections in their natural hosts. Most of the birds examined with clinical signs of BFD or FM exhibited low titers of antibodies neutralizing the BFDV isolate, whereas in clinically healthy birds from flocks that never had any problems with FM or BFD, no antibodies against BFDV could be detected. On account of the results of our experiments described here we suspect that FM might be a milder, more protracted form of a BFDV infection.  相似文献   

Immunological relationship between the New Zealand A and the Australian T strains of infectious bronchitis virus as measured by cross-immunisation tests in tracheal organ cultures from immunised birds     

Lohr JE  Hinze V  Kaleta EF 《New Zealand veterinary journal》1991,39(3):113-114

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

Kaleta EF  Hergarten G  Yilmaz A 《DTW. Deutsche tier?rztliche Wochenschrift》2005,112(12):448-456

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.  相似文献   

The pathogenesis of "egg drop syndrome 76" after experimental infection of one-day-old chicks and laying hens     

M Friederichs  O Siegmann  U Heffels-Redmann  E F Kaleta  U Neumann 《Berliner und Münchener tier?rztliche Wochenschrift》1987,100(2):41-47

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Crane hepatitis herpesviruses     

S Foerster  C Chastel  E F Kaleta 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1989,36(6):433-441

Comparative studies were performed on crane herpesviruses obtained from two different enzootics in Austria and France. The examined viruses appear to be identical in their physico-chemical properties, morphology and biological reactions in ovo. The crane viruses are tentatively classified as beta-herpesviruses. Crane herpesvirus antisera produced in rabbits reacted in cross neutralization tests with each other and with a herpesvirus obtained from a bobwhite quail. No reactivity was observed with other avian herpesviruses and with human herpes simplex virus type 1 and 2.  相似文献   

Untersuchungen zur immunologischen Funktion der Harderschen Drüse des Huhnes     

U. Neumann  E. F. Kaleta 《Zoonoses and public health》1977,24(4):331-339

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Chlamydial infections in feral pigeons in Europe: Review of data and focus on public health implications     

Magnino S  Haag-Wackernagel D  Geigenfeind I  Helmecke S  Dovc A  Prukner-Radovcić E  Residbegović E  Ilieski V  Laroucau K  Donati M  Martinov S  Kaleta EF 《Veterinary microbiology》2009,135(1-2):54-67

Feral pigeons (Columba livia domestica), which thrive in most European towns and cities, are commonly infected with the zoonotic bacterium Chlamydophila psittaci, the agent of psittacosis (also known as ornithosis) in humans. A number of surveys carried out over the last thirty years across Europe have detected high seropositivity values and high percentages of infection in feral pigeon populations. Overall, when considering data from 11 European countries, seropositivity values to C. psittaci in the sampled populations ranged from 19.4% to 95.6%. In most surveys, the complement fixation test was used, and antibodies were detected in 19.4-66.3% of the samples, with a median of 46.1%. Indirect immunofluorescence and ELISA tests were employed less frequently, but led to the detection of higher percentages of seropositivity (23.7-67.7% and 35.9-95.6%, respectively). Attempts to grow C. psittaci in cell culture or embryonated chicken eggs were successful in 2-42.3% and 0-57.1% of samples, respectively, antigen detection methods were positive in 2.3-40% of samples, while conventional PCR and real-time PCR using different genomic targets detected the organism in 3.4-50% of samples. Twenty-five C. psittaci isolates from pigeons were typed as ompA genotype B (n=14), E (n=10) and E/B (n=1). The huge increase of feral pigeon populations in Europe is a major cause of concern for the detrimental effect of pigeon droppings on environmental hygiene, in addition to the extensive damage due to the fouling of buildings and monuments. The most important pathogenic organism transmissible from feral pigeons to humans is C. psittaci, with 101 cases of disease reported in the literature. Exposure to C. psittaci-contaminated dust, direct contact with pigeons through handling and, to a lesser extent, through pigeon feeding have been identified as hazardous exposures in more than half of the human cases, while loose or transient contacts with feral pigeons have been mentioned in about 40% of the cases. Education initiatives as to the communication of a health risk resulting from contact with pigeons and pigeon excreta should primarily be targeted at individuals who may be exposed to C. psittaci-contaminated dust, such as demolition/construction workers. Recommendations to this category of workers include wearing protective clothes with hoods, boots, gloves and air filter face masks when removing pigeon faeces from roofs, garrets and buildings, especially if working indoors. Monitoring for C. psittaci infections in these workers over time should also be considered. Children should be warned not to handle sick or dead pigeons, and immunocompromised individuals should be advised to carefully limit their contact to feral pigeons. Culling of pigeons by shooting or poisoning is both unethical and ineffective as the place of the killed birds in the population is quickly filled by new juveniles or immigrating birds from neighbouring areas. Pigeon-deterring systems, such as nets and plastic or metal spikes applied to buildings and monuments will prevent their fouling, and the administration of contraceptive drugs may allow size regulation of the pigeon populations. Nevertheless, the measure that will ultimately lead to permanent reduction and will establish healthy sustainable populations is the restriction of indiscriminate feeding by pigeon lovers. The erection of dovecotes and artificial breeding facilities should be considered for providing shelter and a balanced diet to the birds, as well as a chance of interaction for pigeon lovers in a hygienically controlled environment.  相似文献   

Duck plague in a water-bird flock     

E F Kaleta  F J Kaup  W Drommer  W Herbst 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1983,30(2):131-136

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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     

Yilmaz A  Kaleta EF 《Veterinary journal (London, England : 1997)》2003,166(1):67-78

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.  相似文献