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Biomedical subjects

R Korbel

Publications and source records attributed to R Korbel.

At least 19 recordsLinked to original sources
PubMed1998

Viscoelastic properties of canine tracheal mucus: effects of structural inhomogeneities and storage.

Tracheal mucus is an inhomogeneous material and thus its viscoelastic properties may vary substantially within a mucus sample. In this study on canine tracheal mucus, we investigated this variation of mucus viscoelasticity and addressed the question whether or not the viscoelasticity is affected by storage of the mucus at low temperatures. Mucus samples were collected from 16 beagle dogs kept under clean air conditions. By means of magnetic rheometry, dynamic viscosity- and elasticity were determined either in the fresh state of these samples or after storage at -80 degrees C. Owing to inhomogeneities within the gel-structure of the mucus, local values of the viscoelastic parameters differed by more than an order of magnitude. Short storage periods (5 d) were found to decrease, long periods (100 d) to increase the viscosity as well as elasticity parameters of the mucus material. These results emphasize the fact that measured viscoelastic properties of mucus are average values depending on the measuring protocol. In addition, these values are modified by storage of the mucus at low temperatures.

Animals↗
PubMed1998

[Comparative investigations on inhalation anesthesia with isoflurane (Forene) and sevoflurane (SEVOrane) in racing pigeons (Columba livia Gmel., 1789, var. domestica) and presentation of a reference anesthesia protocol for birds].

A conventional inhalation anaesthesia using an isoflurane and sevoflurane-oxygen-nitrous oxide-mixture was performed in each six domestic pigeons (Columbia livia Gmel., 1789, var. domestica). Over a period of 60 minutes routine anaesthetic monitoring including reflex score (12 reflexes, cloacal body temperature and pulse oximetry) was performed. For anaesthesia maintainance 4.0 +/- 0.3 Vol. % sevoflurane compared to 2.0 +/- 0.2 Vol. % isoflurane were used. The induction period using sevoflurane was shorter (95 +/- 9 sec) than by using isoflurane (154 +/- 12 sec). The recovery period was significantly shortened using sevoflurane (162 +/- 12 sec) compared to isoflurane with 186 +/- 12 sec. Results show, that the use of sevoflurane is indicated especially in patients bearing anaesthesia risks, but has a number of advantages, though anaesthetic potency is approximately 50% lower than in isoflurane, causing higher costs. Furthermore low toxicity of sevoflurane leads to a lower burden for the surgical staff through so-called "waste gases", which play an important role in avian anaesthesia using a head chamber for application. Beside a review on current techniques in avian anaesthesia this paper includes a standardised detailed anaesthesia protocol description of avian inhalation anaesthesia regarding the technical equipment as well as its practice, which allows an exact documentation of the anaesthetic, meeting legal requirements, too. The results show that inhalation anaesthesia with isoflurane or sevoflurane has to be preferred even in birds when compared to ketamine anaesthesia, the future use of which has to be restricted to sedation and immobilisation partly due to animal welfare grounds.

Anesthesia, Inhalation↗
PubMed1998

[The modified Schirmer tear test in birds--a method for checking lacrimal gland function].

The Schirmer tear test (STT) is an important component of the complete ophthalmic examination in mammals for evaluating lacrimal function. However, no STT reference values for birds have been published to date. 255 ophthalmologically healthy birds (42 different species form seven orders) were tested using a 1-minute STT I (without topical anaesthesia, reflex secretion), STT II (with topical anaesthesia, basal secretion) and as a modification STT III (measurement under isofluran/oxygen, inhalation anaesthesia, a precaution to minimize examination induced stress) using standardized 5-mm-STT strips as well as--under consideration of the size of the palpebral fissure--strips trimmed down to 2 and 4 mm. Mean values (+/- SD) for STT I and STT II were 3.2 +/- 2.7 to 7.5 +/- 2.6 mm/min and 1.7 +/- 1.4 to 4.5 +/- 2.8 mm/min respectively in Psittaciformes (using 4 mm strips), 4.1 +/- 2.7 to 14.4 +/- 7.2 mm/min and 2.0 +/- 1.7 to 4.2 +/- 3.1 mm/min in Falconiformes and 10.7 +/- 4.0 to 11.5 +/- 5.4 mm/min and 3.6 +/- 1.7 to 5.9 +/- 3.1 mm/min in Accipitriformes (using 5 mm strips). Due to the lack of a glandula lacrimalis Strigiformes showed STT levels below 3 mm/min. STT III values were between those of STT I and STT II in Falconiformes and Accipitriformes but not in Columbiformes. On the basis of these results the STT will become an important component of the bird specific ophthalmologic examination procedure allowing more sophisticated examination of lacrimal gland associated avian eye disorders.

Animals↗
PubMed1997

[The problem of free living urban pigeons].

The biology and behaviour of urban pigeons is presented in this article. When changes in the population density of pigeons by capture, shooting, or intoxication are intended, the breeding behaviour has to be considered. A constant reduction of pigeons according to the law for the prevention of cruelty against animals can only be achieved by a restricted feeding if feeding at all.

Animal Feed↗
PubMed1996

[Ostrich farming from the perspective of veterinarians].

The present paper is an attempt to relate the etiology of 54 cases with diseased/deceased ostriches to criterions of keeping, feeding, climate and infectious diseases. Despite the fact that some of the damages diagnosed seem to be avoidable the criterions of the law for the prevention of cruelty to animals are not to be fulfilled since the adverse climatic circumstances in Germany.

Animal Welfare↗
PubMed1994

[Determination of the activity of delta-aminolevulinic acid dehydratase--a method for the diagnosis of lead poisoning in birds].

In avian patients enteral, parenteral and aerogenous lead intoxications are frequently observed. Ingestion of non-metallic lead may not be diagnosed by radiography. Alternatively, estimation of the delta-aminolevulinic acid dehydratase (delta-ALA Dehydratase) activity is a suitable diagnostic test for lead intoxications. The enzyme delta-ALA Dehydratase, which plays a central role in erythropoiesis, is inhibited by lead and is therefore a specific indicator for lead intoxications. The activity of delta-ALA Dehydratase is measured directly in the blood; not the amount of excreted delta-ALA in the urine as in mammals. Blood volumes of 0.45 ml are necessary and thus allow to perform the test in birds as small as 45 g body weight (e.g. Budgerigars). Possible ranges of application as well as a suitable therapy for lead intoxication in birds are presented.

Animals↗
PubMed1993

[Pathologico-anatomic and mycotoxicologic studies of aspergillosis in birds].

4.0% of all birds (n = 11249) examined post mortem at the Institute of Avian Diseases, Oberschleissheim, showed fungal infections of the respiratory tract. Clinical and histopathological findings to date have suggested toxin production in Aspergillus fumigatus infections. To obtain detailed information, preselected tissues from the lungs and air sacs (n = 17) were examined by culture and fluorescence microscopy. In 12 cases gliotoxin (0.1-0.45 mg/kg) was found in the A. fumigatus infected tissues. The importance of gliotoxin, which showed strong cytotoxic effects in cell cultures, is discussed.

Air Sacs↗
PubMed1993

[The occurrence of Chlamydia psittaci infections in raptors from wildlife preserves].

152 free-living raptors found in the area around Munich, Germany, were investigated for possible Chlamydia psittaci infections. Chlamydia psittaci was detected in 13.2% of these birds of prey (Strigiformes, Falconiformes and Accipitriformes) by examination of cloacal swabs with an antigen ELISA (IDEIA Chlamydia test kit). Chlamydia psittaci antibodies could be demonstrated in 85.1% of 121 birds by a Chlamydia antibody ELISA (Chlamydia-psittaci-AK-EIA). 29.7% of the samples investigated were positive, 55.4% showed strong positive reactions. The birds showed neither clinical nor pathological signs of chlamydial infections. The specificity and sensitivity of the Chlamydia antibody ELISA, as determined using positive sera and epidemiological criteria are discussed. Antigen ELISA and the cell culture method showed a consistency of 94%. The results and their consequences for diagnostic procedures and state regulations are discussed.

Animals↗
PubMed1993

[The problems of making birds unable to fly and questions of raising waterfowl in ponds from the viewpoint of animal welfare].

From the viewpoint of the current law on animal welfare, the methods of rendering birds flightless are described and evaluated. Besides the animal welfare, other law statutes are to be paid attention to obligatory when waterfowl is kept on ponds. The raising and fattening of ducks and geese without water to swim on, can also be advocated from the angle of animal welfare.

Animal Husbandry↗
PubMed1993

[Diagnostic endoscopy and sexoscopy in birds].

The main indication for clinical endoscopy in birds is--beside diagnostic reasons--sex determination in monomorphic avian species. Some typical findings, the technical procedure, important differences to endoscopy in mammals and possible complications are described.

Animals↗
PubMed1992

Further investigations on Pasteurella multocida infections in feral birds injured by cats.

A total of 64 Pasteurella multocida strains (46 out of 11 different feral bird species, partly injured by cat bites, and 18 strains originating from clinically healthy cats) were biochemically differentiated. As a result, 67.4% of the strains from feral birds and 61.1% from the cats were classified as the subspecies multocida, whilst 21.7% and 27.8% were identified as the subspecies septica. The percentage of frequency for both the subspecies was of a comparable order of magnitude from the birds injured by cat bites and from cats (58.6% and 61.1%, 24.1% and 27.8% resp.), whereas the frequency from other feral birds differed considerably (82.4% and 17.6%). Maltose-positive strains were only demonstrable in birds with wounds inflicted by cats. To date, maltose-positive strains have only been obtained from one cat and one human being with an injury caused by a cat. The results of this investigation confirm the possibility of the direct transmission of Pasteurella multocida via cat bites. 19 strains from feral birds and 15 strains from cats were tested for their capability to produce toxins. The results of these tests were negative. The present paper also describes the pathologic-anatomical and histopathological lesions caused by the infection in feral birds.

Animals↗
PubMed1992

[Ocular manifestations of systemic diseases in birds. Part 1].

Among the representatives of the class Aves ocular lesions may be a particularly strong indication of systemic disorders. A causative diagnosis of ocular lesions may be vital for the avian patient, not only as a basis for effective therapy of the primary disease, but also for saving the vision, as birds orientate themselves primarily by vision. The following paper presents a synopsis of important ocular disorders in avian patients that are either pathognomonic for certain disorders or, when considered in conjunction with other organic diseases, enable a specific diagnosis to be arrived at. In part 1 bacterial and parasitic etiologies will be described. Part 2 deals with viral infections and noninfectious etiologies.

Animals↗
PubMed1992

[Ocular manifestations of systemic diseases in birds. Part 2].

Among the representatives of the class aves, ocular lesions may be a particularly strong indicator of systemic disorders. A causative diagnosis of ocular lesions may be vital for the avian patient, not only as a basis for effective therapy of the primary disease, but also for saving the vision, as birds orientate themselves primarily by vision. The following paper presents a synopsis of important ocular disorders in avian patients that are either pathognomonic for certain disorders or, when considered in conjunction with other organic diseases, enable a specific diagnosis. Bacterial and parasitic infections were already described in part 1 of this paper. Part 2 gives outlines of possible viral etiologies and noninfectious diseases.

Animals↗
PubMed1992

[Restraint methods in avian patients. Theoretical basis and practical execution. Part 2].

In avian medicine a correct diagnostic and therapeutic procedure requires restraint. Incidents during restraint result most frequently from the ignorance of certain bird-specific physiological and anatomical characteristics. On the basis of theoretical fundamentals, outlined in part 1, the different restraint techniques are described and demonstrated in detail by figures.

Anesthesia↗