Biomedical subjects

E Deegen

Publications and source records attributed to E Deegen.

At least 19 recordsLinked to original sources

PubMed2006

Effects of two different dosages of dobutamine on pulmonary artery wedge pressure, systemic arterial blood pressure and heart rate in anaesthetized horses.

The purpose of the present study was to investigate the effects of two different dobutamine concentrations on pulmonary artery wedge pressure (PAWP) and on mean systemic arterial blood pressure (MAP) in horses anaesthetized with isoflurane, after induction of general anaesthesia with xylazine, ketamine and diazepam. Eight healthy warm-blood horses were included in the study. Each horse was subjected to general anaesthesia twice with two different dosages of dobutamine, 3 and 5 microg/kg bw/min, being infused over 15 min, starting 50 min after induction of general anaesthesia (T(0)). The heart rate, the PAWP and the MAP were recorded after 10 min (T(1)) and then every 5 min until 15 min after cessation of intravenous dobutamine administration (T(3)-T(5)). The PAWP was measured by a right heart catheter, which was positioned in the pulmonary capillaries. Mean systemic arterial blood pressure was monitored at the facial artery for the duration of general anaesthesia. All parameters increased at both dosage rates of dobutamine and decreased significantly when dobutamine administration ceased. The increase in heart rate was significantly higher after administration of 3 microg/kg bw/min dobutamine compared with the dosage of 5 microg/kg bw/min dobutamine. The increase in MAP was also higher at this dosage, but not significantly different to the dosage of 5 microg/kg bw/min dobutamine. During both dosages the MAP was above a value considered to be compatible with good peripheral circulation. The greater increase in PAWP was observed during administration of 5 g/kg bw/min dobutamine, but PAWP was not significantly different with the dosage of 3 microg/kg bw/min dobutamine. In conclusion, the administration of dobutamine led to an increase in MAP and PAWP above a value considered to be compatible with a good peripheral circulation. The results of the present study indicate that dobutamine improves circulation, in addition to its well-known effect on the periphery.

Adrenergic beta-Agonists↗

PubMed2005

[The development of verrucous pastern dermatitis syndrome in heavy draught horses. Part I: Review of the literature].

Verrucous pastern dermatitis is a chronic hyperplastic dermatopathy of the feet of horses which is characterized by a greasy, odorous coating of the skin and, in advanced stages, by clearly demarcated calluses and wart-like proliferations. The disease occurs almost exclusively in cold-blooded and other heavy horses, with certain breeds affected most frequently. It is considered a distinct disease entity within the framework of pastern dermatitis syndrome. There is no consensus in the literature about relationship of the disease to the sex and age of the horse. Horses with a high cannon circumference and pronounced fetlock tufts of hair seem to be affected most severely. In chiefly anecdotal reports the cause of the disease or its aggravation has been ascribed to housing conditions and environmental influences, chemicals, mechanical insults, feeding, or infections with Chorioptes skin mites. It thus seems likely that the disease is affected by a variety of factors. Although verrucous pastern dermatitis has been known for hundreds of years, its etiology and pathogenesis remain unclear.

Age Factors↗

PubMed2005

[Verrucous pastern dermatitis syndrome in heavy draught horses. Part II: Clinical findings].

In the present field study the skin of the feet of 37 heavy draught horses of different breeds showing verrucous pastern dermatitis was examined clinically. Included were the degree of severity of the disease and the prevalence of anatomically normal structures associated with the skin: fetlock tufts of hair ("feathering"), ergots, chestnuts, bulges in the pastern region, cannon circumference. Each horse was examined for Chorioptes sp. skin mites. Information was also collected on the development of the skin alterations and housing conditions and feeding. These individual data were correlated with the clinical degree of severity of verrucous pastern dermatitis, which was evaluated using a numerical code (scoring system). In addition, punch biopsies were taken from the diseased skin of the feet and from healthy skin of the neck for comparative patho-histological examination (see Part III). Verrucous pastern dermatitis is a chronic disease which can be divided into four groups: scaling (group I), hyperkeratotic and hyperplastic plaque-like lesions (group II), tuberous skin masses (group III), and verrucous skin lesions with rugged surfaces (group IV). No correlation was found between the clinical degree of severity of the skin lesions and sex, breed, amount of work, use of stallions for breeding, grooming condition of the hair, white markings in the foot region, or Chorioptes sp. infestation. In regard to feeding it was found that the amount of maize and oats fed had some influence on the clinical degree of severity. Statistical analysis revealed a significant correlation between the clinical degree of severity and the age, the grooming condition of the hooves, and the mean cannon circumference. The prevalence of fetlock tufts of hair, chestnuts, ergots, and anatomically normal bulges in the pastern region also increased significantly with the clinical degree of severity. Furthermore the study revealed that the clinical degree of severity depended on the hygienic conditions of the stables and of the ground where the horses were kept outdoors.

Animals↗

PubMed2004

Sensitivity of commercial prothrombin time reagents to detect coagulation factor deficiencies in equine plasma.

The sensitivity of commercial prothrombin time (PT) tests was assessed based on a dilution series of equine pooled plasma (EPP) (experiment 1) and on 40 equine plasma samples with reduced activity of coagulation factors II, V, VII and X (experiment 2). Two different PT reagents (reagent 1, human placental thromboplastin; reagent 2, recombinant human tissue factor) were used according to the manufacturers' instructions (standard test, PT([ST])) and compared to a modified test procedure (modified test, PT([MT])) using sample dilution and fibrinogen addition. In all samples, sensitivity was lower (P<0.01) when using PT([ST]) with reagent 2 (0.20) than when using either PT([ST]) with reagent 1 (0.65) or PT([MT]) with both reagents (reagent 1, 0.60-0.75, reagent 2, 0.58-0.70, depending on sample dilution). The highest sensitivity was found for PT([MT]) when using a 1:20 sample dilution. In those samples in which at least one coagulation factor activity was decreased (by 20%; n=18), the sensitivity of PT([ST]) with reagent 2 (0.33) was found to be inadequate, in contrast to all other test procedures (0.83-0.94). This low sensitivity corresponded to shorter time intervals between different coagulation activity levels prepared by EPP dilution. The results indicate that adequate sensitivity of PT measurements in equine plasma can be achieved using a standard test procedure as long as a suitable reagent is used.

Animals↗

PubMed2004

Retrospective analysis of 50 cases of guttural pouch tympany in foals.

Between 1994 and 2001, guttural pouch tympany was diagnosed in 51 foals; there were approximately three times as many fillies as colts, of Arabian, different German warmblood breeds and Western horse breeds. There were significantly more Arabian and paint horse foals than expected in comparison with the breed distribution of the foals hospitalised at the Clinic for Horses. The foals' breed and sex did not influence the age of onset, the type and severity of the clinical signs or the recurrence rate. A surgical laser technique was used on 50 of the foals; in 35 cases only one surgical treatment was necessary, in seven cases a second operation was required during the foal's initial period of hospitalisation, and in eight cases a second operation was performed during a second period of hospitalisation. Long-term follow-up information was obtained for 44 of the 50 treated horses; 24 of them were under two years of age and 20 were over two years of age. In six horses, no follow-up information was available. Four horses were euthanased for reasons unrelated to the condition or its treatment. The horses over two years of age were in training or were being used for competitions in dressage or jumping or for breeding purposes, and in only one of them was an adventitious respiratory noise reported. All the horses up to two years of age were reported to be healthy.

Animals↗

PubMed2004

[Influence of detomidine on echocardiographic function parameters and cardiac hemodynamics in horses with and without heart murmur].

30 warmblood horses were examined before and after sedation with 20 micrograms/kg BW detomidine, to determine changes of cardiac function parameters, using B-mode, M-mode and Doppler echocardiography. 15 horses showed a heart murmur, but no clinical signs of cardiac heart failure, 15 horses had neither a heart murmur nor other signs of cardiac disease. After sedation with detomidine we could recognise a significant increase of end-diastolic left atrium diameter, an increase of end-systolic left ventricular diameter and aortic root diameter. The end-systolic thickness of papillary muscle and interventricular septum showed a decrease. Fractional shortening and amplitude of left ventricular wall motion was decreased after sedation. The mitral valve echogram revealed a presystolic valve closure and an inflection in the Ac slope (B-notch) in xy horses before sedation. Both increased after sedation with detomidine. Doppler echocardiography showed a decrease of blood flow velocity and velocity time integral (VTI) in the left and right ventricular outflow tract after sedation. Regurgitant flow signals were intensified following sedation in xy horses, especially at the mitral valve.

Animals↗

PubMed2003

[Experimental studies on the therapy of epiglottis hypoplasia in horses--transendoscopic injection of collagen and polytetrafluoroethylene].

Epiglottic augmentation by transendoscopic injection of an implant material was performed on ten clinically healthy horses. In six cases bovine collagen (Zyplast) was used, in the remaining four horses the injection was done with polytetrafluorethylene (PTFE-Paste). The results of the surgery were observed endoscopically and by contrast radiography. Using the radiographs, epiglottic length and thickness were measured. For necropsy and histologic assessment the horses, three and two animals of the two groups, were euthanized at three and 12 weeks after surgery. The data obtained from the measurements at necropsy were correlated with those from the radiographs. The minimal invasive technique was very easy to perform with the bovine collagen while PTFE was less suitable for the transendoscopic injection. The data concerning the epiglottic length as well as its thickness measured on the radiographs correlated well to those obtained from the measurements at necropsy. After injection of collagen as well as PTFE an organisation of the implant was noticed histologically, which increased in accordance with the increasing time after injection. As far as the collagen implant is concerned, there was fibrous granulation tissue accompanied by an inflammatory reaction consisting mainly of lymphocytes and histiocytes. In contrast the injection of PTFE led to the development of a foreign body granuloma. In addition, some cases showed ulcers. Both implant materials led to an increase in epiglottic thickness, so that one can expect an improvement in its stability which could be of benefit to the therapy of epiglottic hypoplasia. But this increase in thickness had its maximum level directly after injection and declined over the period observed. Still, especially in the case of the collagen used here, the development of a fibrous granulation tissue and the immigration of fibroblasts and fibrocytes into the implant indicates that there is a stabilisation to some extent. Bovine collagen was proven to be highly suitable for transendoscopic injection. Although there is report about good clinical results using PTFE via laryngotomy, this material seems to be unsuitable for the transendoscopic technique due to the circumstances that lead to a higher number of complications.

Animals↗

PubMed2003

[Effects of excess caloric fat feeding on the lipid metabolism in Shetland ponies].

To investigate the influence of overweight and dietary fat supplementation on lipid and insulin glucose metabolism of Shetland ponies, eight Shetland pony geldings were fed a hypercaloric (30 MJ DE/150 kg bwt. and day) fat diet (10% fat as soybean oil) or a carbohydrate control diet for nine months until ponies gained an overweight of 15%. Afterwards oral glucose tolerance tests (oGTT; 5, 6 mmol/kg bwt.) were performed after a 12 hour fast and after a fast which led to an increase of plasma triglyceride concentrations to a threshold of 3 mmol/l (36-65 hrs.). Plasma concentrations of glucose, insulin, triglycerides and non esterified fatty acids (NEFA) were determined for 480 minutes after the glucose load. Ponys having had received the control diet tended to a higher insulin secretion in case of both oGTTs, whereas the glucose tolerance was similar in both groups but lower than in ponies of normal weight. During the oGTTs after fasting leading to the plasma triglyceride threshold, triglyceride concentrations decreased significantly (p < 0.05) faster and stronger in fat fed ponies. Additionally, fat fed pony showed significantly (p < 0.05) lower NEFA levels. The results of this study demonstrate a positive effect of fat feeding on the triglyceride clearance of overweight Shetland ponies.

Animals↗

PubMed2003

[Standing behavior in horses after inhalation anesthesia with isoflurane (Isoflo) and postanesthetic sedation with romifidine (Sedivet) or xylazine (Rompun)].

Isofluorane is a modern, only slightly depressive inhalation anaesthetic with excellent pharmacologic characteristics in use in equine medicine. In contrast to halothane, isofluorane is hardly broken down in the liver, but is eliminated by the lung. It low solubility in blood permits excellent control of anaesthesia. However, due to its swift elimination from the organism there is heightened risk of premature recovery from isofluorane anaesthesia. In this study the recovery phases of 96 horses were monitored for its duration and the animals' physical coordination. The horses were divided into four groups. Two groups were sedated with xylazine, one of which received postanaesthetic sedation with xylazine, the other saline solution only. The other two groups were sedated with romifidine, either with or without postanaesthetic sedation after general anaesthesia. In this study the horses of Group 4, sedated with 0.02 mg/kg BW romifidine at the moment of extubation, showed the best recovery phase. The number of attempts to arise was reduced and coordination was better. Similar results were obtained by postanaesthetic sedation with 0.2 mg/kg BW xylazine (Group 2). Premedication with 0.08 mg/kg BW romifidine without postanaesthetic sedation (Group 3) could be carried out at mean duration of anaesthesia of 85 minutes with no negative effects observed during the recovery period. Premedication with xylazine without postanaesthetic sedation (Group 1) is not to be recommended, as the number of attemps to stand up was significantly higher and coordination was either weak or significantly poorer than in the other three groups. The results of this study show that post-anaesthetic sedation of horses with an alpha 2-adrenoceptor agonist can improve the recovery phase after inhalant anaesthesia with isofluorane in regard to the number of attempts to arise and the animals' physical coordination.

Adrenergic alpha-Agonists↗

PubMed2003

[Bacteriological findings for endodontical and apical molar dental diseases in the horse].

In most cases the diagnosis of any molar dental disease in horses is made at an advanced stage, so that permanent restoration of the diseased teeth is not feasible. Complications such as bacteraemia and septicaemia due to infections as a result of dentogenous sinusitis and following dentosurgical procedures have been described in human medicine and in veterinary medicine. Twenty patients were available for examination from the Clinic for Horses of the School of Veterinary Medicine Hannover with molar dental disease in upper or lower jaw. As a result of this disease the infected tooth had to be removed surgically. The aim of this study was to determine the presence of and to identify microbes in 20 patients. Swab samples were taken from infected pulpa, from dental abscesses and from involved nasal sinuses. The samples were examined microbiologically and tested for aerobes and anaerobes at the same time. Infectious agents were found in 19 of 20 horses. In all, 27 different species of infectious agents were isolated, including both aerobic and anaerobic microbes. Fifteen patients (75%) showed a mixed flora. Further differentiation indicated a preponderance of the group of gram-negative obligatory anaerobic agents isolated from a total of 17 horses. In all these samples there was a high concentration of infectious agents of these genera, the most common of which were Prevotella spp (n = 16) and Fusobacterium spp. (n = 15). Pre-surgical antibacterial therapy is recommended to reduce the risk of intra- and/or post-surgical bacteraemia and its serious consequences. In light of these microbiological results and considering the high degree of resistance among all anaerobic microbes, all patients in this study were treated with Amoxicillin.

Animals↗

PubMed2003

[Population genetic analysis of the heritability of gutteral pouch tympany in Arabian purebred foals].

The objective of the present study was to analyse the importance of the influences of the sex, inbreeding coefficient and the additive genetic contribution to the occurrence of guttural pouch tympany in Arabian foals. Horses affected by guttural pouch tympany were ascertained in the Clinic for Horses, School of Veterinary Medicine Hannover. The data comprised 27 Arabian purebred foals with guttural pouch tympany. Of these 27 animals 22 were patients of the Clinic for Horses between 1994 and 2001 and 5 Arabian foals were sampled on the studs. Information on the pedigrees of these patients allowed us to sort in the affected foals into four families with a total of 276 animals. Female foals were more often affected by guttural pouch tympany. The difference was 11.9% in favour of female foals. The size of the inbreeding coefficient was not important for the occurrence of guttural pouch tympany. The heritability estimate for the frequency of guttural pouch tympany using a threshold model was 0.49 +/- 0.28. This is the first report that could show a genetic component responsible for guttural pouch tympany in foals.

Animals↗

PubMed2002

[Influencing respiratory gas analytical lung function parameters by intravenous injection of clenbuterol in horses with chronic lung diseases].

In a placebo-controlled drug study data were collected about flow, volume and expiratory CO2-concentration in 13 horses with chronic obstructive pulmonary disease before and until 2.5 h after intravenous injection of clenbuterol. An ultrasonic flow measuring unit and an infrared-CO2-analyser (Spiroson Scientific) were used. functional deadspace and expiratory mixed volume were calculated. In addition the effect on the partial pressure of oxygen (PaO2) and carbon dioxide (PaCO2) in arterial blood was tested and the alveolo-arterial oxygen difference (AaDO2) determined. The volume of the functional deadspace directly after injection of clenbuterol was 24% bigger than the one after placebo injection. 45 min after injection there was no significant difference anymore. The PaO2 showed a decrease with a maximum difference of 11.6 mmHg to the starting value at 45 min after the injection of clenbuterol. As the PaCO2 didn't show significant changes this resulted in an increase of the AaDO2 of up to 15 mmHg (45 min p. inj.). All these alterations had a short-term character and started approaching their basic values 45 min p. inj.. Only the PaO2 did not reach the starting level 150 min after injection of clenbuterol. The expiratory mixed volume didn't show a straight tendency. On the one hand the results indicate that the functional deadspace is an interesting pathophysiological parameter. On the other hand the combined presentation of the changes in blood gas-tension and deadspace volume after the injection of clenbuterol gives indications, that the increase of anatomic deadspace caused by bronchospasmolysis combined with a delayed opening of alveoli, that were not ventilated beforehand, are the reason for the initial decrease in PaO2. Other reasons are discussed.

Animals↗

PubMed2001

Detection of equine herpesvirus type 2 (EHV-2) in horses with keratoconjunctivitis.

The prevalence of EHV-2 in 27 horses with keratoconjunctivitis and 21 clinically healthy horses of different ages and stocks were analyzed. We demonstrated that EHV-2 was present in 12 keratoconjunctivitis cases as shown by nested PCR on ocular swabs. This is statistically more often than in the control group, where only two ocular swabs were EHV-2 positive. Cocultivation was successful on peripheral blood leukocytes of healthy and diseased horses but not on swabs. We isolated ten EHV-2 strains from diseased and nine from control horses, whereas 16 isolates showed different restriction enzyme patterns. The results of immunfluorescence and neutralization tests are predictory only in combination with the nested PCR data on ocular swabs. A successful antiviral treatment in nine out of 16 cases supports the aetiological role of EHV-2 in this ocular disease.

Animals↗

PubMed2001

Glucose-dependent insulinotropic polypeptide (GIP) and the enteroinsular axis in equines (Equus caballus).

To investigate the enteroinsular axis (EIA) in equines oral (oGTT) and intravenous (i.v.GTT) glucose tolerance tests (5.6 and 1 mmol glucose/kg BW, respectively) were performed with healthy, normal weight large horses and Shetland ponies. Plasma was analysed for concentrations of glucose, glucose-dependent insulinotropic polypeptide (GIP) and insulin. In all equines plasma GIP concentrations only increased significantly when glucose was administered orally. The insulin glucose ratio (IGR) was significantly higher during the oGTT than during the i.v.GTT in both races. Basal plasma glucose levels were significantly higher in large horses than in ponies in both experiments. During the oGTT maximum glucose values were significantly higher in ponies. Ponies tended to a higher insulin secretion but the IGRs were identical in both races after oral and intravenous glucose administration. One clinically inconspicuous pony showed hyperinsulinaemia and, in case of the oGTT, insulin resistance, glucose intolerance, and GIP hypersecretion. The results of this study indicate the existence of an EIA in equines due to the higher IGRs during the oGTT. Furthermore, the similarity of plasma GIP levels and IGRs in ponies and large horses suggest a comparable activity of the EIA in both races. Regarding the elevated plasma GIP concentrations of the insulin resistant pony the EIA appears to participate in equine hyperinsulinaemia.

Administration, Oral↗

PubMed2001

Effects of fat feeding and energy level on plasma metabolites and hormones in Shetland ponies.

The aim of this study was to investigate the influence of a fat-supplemented diet compared with a carbohydrate diet on the lipid metabolism and the enteroinsular axis of Shetland ponies. The 'crossover' experiment was divided into two parts: in the first 10 weeks the diets comprised the correct number of calories according to requirements and in the following 10 weeks they were hypercaloric, in order to check the effect of a different energy content of the diets. Feeding the fat-enriched diet, independently of its energy content, led to a significant decrease in plasma triglycerides, associated with a mean 50% increase of plasma lipoprotein lipase activity. After oral glucose load the ponies on fat-enriched diets showed higher plasma glucose concentrations. Oral glucose administration after feeding the hypercaloric fat-enriched diet led to a 25-fold increase of plasma insulin levels. Glucose-dependent insulinotropic polypeptide plasma levels were increased in the animals on the fat-enriched diets. The results of this study suggest that fat feeding improves triglyceride clearance. However, the fat supplementation of the diet also led to impaired glucose tolerance. These results are important for a better understanding of the function of the enteroinsular axis. To investigate the influences of fat on lipid metabolism in relation to the aetiopathogenesis of equine hyperlipaemia further studies involving diseased animals are needed.

Animals↗

PubMed2000

[Occurrence of various immunoglobulin isotopes in horses with equine recurrent uveitis (ERU)].

We investigated 30 healthy eyes and 41 eyes with ERU from 57 horses. The total immunoglobulin titers and titers of IgGa, IgGb, IgM were measured in aqueous humour, vitreous and serum using different ELISA techniques. Every sample investigated contained detectable amounts of immunoglobulins. Compared to control eyes significantly increased titers were found in the aqueous humour and vitreous of the ERU eyes for all immunoglobulin isotypes studied (p < or = 0.01). While IgM was detected in only 2 out of thirty aqueous humour and in none of the thirty vitreous samples of healthy eyes, 79.6% of samples of ERU eyes revealed considerable IgM titers. Changes of the IgGa/IgGb ratio in the eye as compared to that in the autologous serum was more frequent in affected than in healthy eyes. In contrast to the intraocular immunoglobulins there were no significant differences in immunoglobulin serum titers in healthy horses and those affected with ERU (p > 0.05). In conclusion, the results argue for a physiological appearance of immunoglobulins in the healthy eye. The increased titers of immunoglobulins in eyes stricken with ERU might be signs either of a local ocular production of antibodies and/or an increased permeability of intraocular barriers.

Animals↗

PubMed2000

[Diagnosis of stomach carcinoma in the horse].

In 10 horses, which were referred to the clinic with the suspicion of disorders of the gastrointestinal tract, gastroscopy revealed a gastric tumour. In ten cases the diagnosis of a squamous cell carcinoma was made on the basis of histology of biopsies or autopsy. The tumour always derived from the non-glandulary mucosa. The horses showed various clinical symptoms. All patients had a hypoalbuminemia and a hyperglobulinemia in the serum electrophoresis. This suggests that a gastric tumour can be suspected intra-vitam even without gastroscopy of the patient.

Animals↗

PubMed2000

[New fundamental order of the School of Veterinary Medicine Hanover].

On June 29, 2000, the Council of the School of Veterinary Medicine Hannover (TiHo) passed a new fundamental order. Upon termination of the current terms of office of the rector and the chancellor in September and at the end of the year 2001, respectively, a school management will be established with a longer term of office and a new type of School Council. However, the new fundamental order must still be approved by the Lower Saxony Ministry of Science and Culture. This change has been made necessary by radical restructuring affecting all universities in Lower Saxony: the transformation to a state enterprise with the concomitant introduction of a global budget demands full-time management. This is a step of historical significance, for this change in the fundamental order puts an end to a tradition of 87 years at the School of Veterinary Medicine Hannover under a constitutional rectorate. The following essay describes the most important changes and explains their necessity.

Faculty↗