Tierärztliche Fakultät - Digitale Hochschulschriften der LMU - Teil 01/07 Archiv

Anesthesia of Rainbow trouts (Oncorhynchus mykiss) with clove oil and BHA – stress and product quality In the questioned experiment three different methods of anesthesia were tested on their influence of product quality and the possibility to minimise stress on the rainbow trouts to be slaughtered. One group was anesthesized by clove oil, another by BHA. Those were compared to a group stunned by a blow on the head. The effect of stress was measured by screening of HKT and catecholamines in the blood and by surveillance of behaviour during anesthesia. Product quality was judged out by sensory tests, optical examination of carcasses and concentration of anaesthetics in the blood. All three methods of anesthesia worked within a limited time, with no animal showing signs of typical behaviour under stress. Blood parameters did give hints for no or very low stress. In the mean of sensory testing a few persons were able to detect clove taste. Carcasses showed no sign of visible damages. All three methods of anesthesia are though likely to carry out anesthesia of rainbow trouts for slaughter without negative effects on product quality and in the means of animal welfare.

This thesis treats the volume segmentation and three-dimensional reconstruction of the CT and dissection image data sets of the „Visible Animal Project“ by means of the VOXEL-MAN-System. In consequence one has here succeeded in producing a volume data based computer model consisting of 779 structures detailing the anatomy of the head of a dog, pro-viding a previously, until now unattainable photorealistic image representation and accuracy of detail. 23 „intelligent animations” (intelligent movies) were calculated and compiled on the basis of this model, available by means of the visualisation program InsideDOG: The Head. The intelligent movies provide the user with the means of seemingly rotating and altering the model freely. Furthermore all segmented structures may be readily identified and accessed by mouse action. The tutorial program provides an ideal supplement to traditional learning and teaching programs, limited as they are in their dimensional representation. The possibilities of visualisation of the three-dimensional animations are clarified and explained by means of specifically selected animations. In addition to the calculation and measuring of intelligent movies the model also provides a means of compiling anatomical pictures and drawings for textbooks, atlases and other multi-media tutorial systems. This simulation of examination methods and surgical procedures provides also the possibility of being employed in scientific and clinical realms.

Laboratory rabbits are frequently used in animal experimental research. The aim of the present study is to compare the heart functions of New Zealand White Rabbits (WN) to the one of Chinchilla Bastard Rabbits (CB) in vivo and in vitro. The higher stress susceptibility of New Zealand White Rabbits noticed in clinical observations is to be examined based on parameters of cardiac contractility. To determine the morphometric parameters and the contractile function of the heart, six animals at a time anaesthetized with Propofol are examined by means of echocardiography. As a result the thickness of the heart wall and the diameter of the left ventricle are determined, and the fractional shortening is calculated. All parameters are measured at the end of systole and diastole. In the next step single cardiomyocytes of six additional animals from each race are enzymaticly isolated from the removed hearts with a modified Langendorff-Perfusion-Apparatus. The contractility of the single cells is analysed under controlled conditions as well as under ß-agonist stimulation with Isoprenalin concentrations of 10-11 to 10-6 M. In terms of the strength of the heart wall or the left ventricle’s diameter, the ultrasound investigations don’t yield any significant differences. However Chinchilla Bastard Rabbits show a significantly higher fractional shortening (40,19 ± 3,19 %) than New Zealand White Rabbits (35,49 ± 3,78 %). Regarding the single cardiomyocytes a distinct difference in the duration of basal shortening can be noticed. WN clearly show a longer shortening period (255,80 ms) than CB (208,73 ms). Cardiomyocytes of WN respond to very low Isoprenalin concentrations from 10-11 to 10-10 M with a significantly higher shortening speed. Broad differences in the fractional shortening of the single cells arise during the experiments with the highest concentration of Isoprenalin (10-6 M). The fractional shortening of cardiomyocytes from WN amount to 7,47 %, whereas the cardiomyocytes from CB reach 9,89 %. On the single cell level WN react more sensitively to the stimulation with increasing Isoprenalin until a threshold of 10-8 M. Beyond that level the contractility decreases visible. However on the organ level the CB have basal a higher contractility. The breed specific results found in this research study could be caused by differences in sensitivity, regulation and the number of ß-receptors as well as by differences in anaesthetic behaviour. Further investigations on a biochemical and molecular level should be carried out to answer these questions.

Nowotni, A. (2003): Clinical examination of cattle for BSE at the slaughterhouse in Munich The aim of the present study was to investigate the reactions of BSE-free cattle at the slaughterhouse to the in vivo BSE-test for cattle of BRAUN et al. (1997). A total of 949 female cattle, older than 24 months and with a negative result in the rapid BSE-test, were examined at the slaughterhouse in Munich. Only behaviour and sensitivity (reactions to touch, sound, light, broom) could be assessed, as the locomotion could not be recorded in all animals. The time taken for the examination per animal was about three minutes. The examination of behaviour and sensitivity was conducted as described by BRAUN et al. (1997). When using the hand or the pen to touch the animal, and when using the broom, the examinations described by BRAUN et al. (1997) were modified. For assessment of the recorded reactions the scheme of BRAUN et al. (1997) was adopted with modifications, to assess the probability for BSE for each individual cow. About a third of the examined animals showed behaviour which was assessed as positive, according to the aforementioned conditions. When touching the animal with a pen more than half of the examined animals responded with at least one BSE-typical reaction. The specificity for the category “profoundly BSE-suspect” was found to be 97.8 %. When excluding all animals with BSE-symptoms, the specificity fell to 63.7 %. In the present investigation only a statement can be made for specificity, as none of the examined animals reacted positive in the rapid BSE-test. A clinical examination at the slaughterhouse can not be recommended. The cost benefit analysis is unpromising. Continuation of the obligatory rapid BSE-test for slaughtered cattle may have to be reviewed if the incidence of BSE keeps decreasing.

LAPAROSCOPIC LIVE DONOR NEPHRECTOMY AND AUTOTRANSPLANTATION AFTER PERIVASCULAR PAPAVERINE APPLICATION - EXPERIMENTAL STUDY IN PIGS The aim of this study is to evaluate whether renal function and blood perfusion can be enhanced by periarterial application of papaverine during laparoscopic donor nephrectomy in pigs. The study is subdivided in two parts. In part one, intraoperative urine output and creatinine-clearance are measured to investigate the influence of perivascular papaverine on renal function during the laparoscopic procedure. In part two of the study, blood perfusion of both kidneys during laparoscopic left donor nephrectomy is determined using fluorescent-labeled microspheres to analyse the vasodilatative effect of papaverine. In a subgroup of animals the donor nephrectomy is followed by autotransplantation and initial renal function is measured for a period of 24 hours after papaverine administration and laparoscopic nephrectomy. Histopathological examination of random samples is performed to evaluate structural damage following nephrectomy and autotransplantation. This study is carried out to refer to the actual clinical situation. After perivascular administration of papaverine an increase of renal function during laparoscopic nephrectomy can be achieved. Compared to controls urine output and creatinine-clearance is significantly improved after local papaverine application. In part two of the study measurement of renal blood flow shows enhanced renal perfusion after application of the vasodilatator in the treatment group. After autotransplantation the papaverine group exhibits an improved initial renal function. Enhanced creatinine-clearance has to be varified by further experiments. Histopathological signs of tissue damages of various extend can be found in all samples. The results presented are interpreted as follows: local periarterial application of papaverine increases renal blood flow during laparoscopic donor nephrectomy. Therefore renal function seems to be augmented. In controls decreased organ perfusion seems to lead to impaired renal function. In consequence the presented study demonstrates a significant better graft function in the treatment group. This method might have the potential to significantly improve graft quality after laparoscopic live donor nephrectomy in human patients.

Die Wirkung der prebiotisch wirksamen Substanz Lactoferrin wurde an neonatalen Hundewelpen getestet. Diese wurden am 3. Lebenstag von der Mutter getrennt, in eine Kontroll- bzw. 4 Lactoferringruppen mit unterschiedlichen Dosierungen eingeteilt und mutterlos mittels Milchaustauscher aufgezogen. Es wurde die Gewichtsentwicklung und Futterverwertung, Mikrobiologie des Kotes, Lactat- und Ammoniakgehalt im Kot, sowie der Kot-pH und Blutwerte untersucht. In den Lactoferringruppen wurde eine Erhöhung der Lactatgehalte und erniedrigte Ammoniakwerte im Kot festgestellt. Die aeroben Gesamtkeimzahlen, sowie die Enterococcengehalte wurden durch Lactoferrin verringert, die milchsäurebildenden Keime gefördert. In den Lactoferringruppen waren die Lymphozytenzahlen ab der 10. Lebenswoche um durchschnittlich 35 % im Vergleich zur Kontrolle reduziert.

This study aimed at establishing a method for checking the efficacy of probiotic substances in beagle puppies, in accordance with the requirements of the Guidelines for the assessment of micro-organisms in the animal categories dogs, cats and horses of the European Commission of October 2000. The orphan rearing of neonatal puppies was chosen as trial method, the only method to ensure avoidance of interindividual differences such as quality and quantity of mother milk. Another advantage is exact standardisation by exact prerequisites (time of weaning, type and frequency of feeding, keeping facilities, sample collection, choice of parameter, methods of analysis). In two different feeding trials with beagle puppies (duration 14 weeks) the efficacy of the prebiotic substance Lactoferrin (n=23) and of the probiotic bacteria Enterococcus faecium (n=12) on neonatal organisms was analysed. It has become clear that the general status of the puppies could be sufficiently assessed by general clinical parameters (clinical examination, food intake, weight development, quantity and consistency of faeces, blood parameter). As far as these parameters could be determined based on scoring systems, they contributed to the assessment of the substances as so-called “supporting data“. The specific parameters directly related to the probiotic action that could be established in this model are, among others, ph analysis, ammonia and lactate determination as well as microbiological analyses of faeces. Furthermore gut wall samples of duodenum and colon could be taken for immunohistochemical analysis. Antioxidative and immunmodulatory effects were assessed by means of determining trolox equivalent antioxidative capacity, vitamine E and C, uric acid, bilirubin, free ferrum, lactate, CK and GOT, the overall content of IgG and IgA, and the specific content of antibodies against humane serumalbumine in plasma. The two feeding experiments show what principles can be applied for examining the effect of prebiotically or probiotically effective substances in small animals by means of scientific standards for carrying out experiments, documenting and analysing them. Thus these experiments provide a basis for appropriate application of minimum quality standards in examining these substances, according to the requirements of the European Commission in October 2000.

The present study aimed to investigate the effect of oral administration of a probiotic containing Ec. faecium (Total concentration 1 x 108 cfu / 100 g dry matter of feed) on the development and health status of hand reared beagle puppies. For this experiment each control group, respectively each trial group consisted of 6 puppies. The trial began on day 3 after the birth of the puppies in order to ensure sufficient intake of colostrum, and ended on day 98. General health status, clinical parameters, daily feed intake, weight gain, amount of faeces and faeces consistency were recorded. Apart from that 8 blood samples were taken to determine immune status, and 4 for establishing blood parameters. Faeces samples were taken continually in order to determine the dry matter. At 4 different periods there were microbiological analyses as well as a determination of lactate and ammonia in each individual puppy’s faeces. To determinate a specific immune response, humane serumalbumin (hsa) was applied in week 8 and 12, and the serum concentration of total IgG, IgA and specific antibodies against hsa were measured. The probiotic affected the puppies´ general health status slightly negatively during the first 8 days of the trail, resulting in sleepiness, yawning, reduced suckling, reduced muscular tone and reduced feed intake. Besides that no negative effects of the probiotic on the puppies´ health were discovered. The feeding of Ec. faecium did neither influence weight gain nor feed intake. The trail group showed a 6.5 % better feed conversion during the period of mixed feeding with Pedigree and milk-replacer. No effect of the probiotic on red blood cells and thrombocytes was discovered, but the trial group showed on average a tendentious higher count on lymphocytes, neutrophil granulocytes and monocytes. Ec. faecium feeding resulted possibly in a raised number of macrophages, and herewith monocytes, a stronger immune response with more lymphocytes and a higher phagocytotic activity of neutrophil granulocytes. The lower IgG serum concentration of the trail group from week 2 on could be related to the probiotic, higher average values of IgA in week 2 and 4 suggested a stimulation of mucosal immunity by the additive. In the trial group, the probiotic feeding seemed to result in a higher count of total aerobe bacteria with a lower share of E. coli, in higher Enterococcus counts and throughout lower shares of Cl. perfringens positive animals. These facts are as desirable for the maintenance of the intestinal eubiosis, as is the discovery of a higher average count on Lactobacillus spp. in the trail group. The count on aerobe bacteria, Cl. perfringens, Enterococcus spp. and Lactobacillus spp. decreased with ongoing age of the puppies. In the period of milk-replacer feeding, probiotic feeding seemed to result in a decrease of fecal dry matter. Considering the high spread of single values, no significant effect of Ec. faecium on fecal lactate and ammonia concentration was discovered, although the probiotic seemed to lower fecal ammonia concentration at the beginning of the trail.

Die Vorhersage der Fertilität und die Aufklärung von Zusammenhängen zwischen der Befruchtungsfähigkeit und Parametern im Organismus ist in der Reproduktionsmedizin ein zentrales Anliegen, um eine effizientere Selektion hochfertiler Tiere zu erreichen. Das Seminalplasma wurde als geeigneter Parameter zur Beurteilung der Fertilität identifiziert, da die positive Beeinflussung der Spermienmotilität und die Vorverlegung der Ovulation durch Seminalplasma nachgewiesen wurde. Diese Arbeit hatte das Ziel anhand verschiedener Pietrainebergruppen und Hybridebergruppen einerseits Komponenten des IGF-Systems im Eberseminalplasma zu identifizieren und ihren Einfluss auf die Fertilität zu überprüfen, andererseits mittels der Proteomics-Technik das komplexe Proteingemisch im Eberseminalplasma zu analysieren. Es wurde das Vorhandensein von IGF-I/II im Eberseminalplasma nachgewiesen, ein Zusammenhang mit der Fertilität bestand nicht. Die Untersuchung der IGFBP-Aktivität ergab beim Vergleich der verschiedenen Pietrainebergruppen signifikante Unterschiede in der relativen Intensität der IGFBP-Banden, die Hybrideber bestätigten diese Ergebnisse nicht. Um eine möglichst einfache, nicht radioaktive Testung dieser IGFBP-Aktivität zu ermöglichen, war es nötig, zu ermitteln, um welche IGFBPs es sich bei diesen Banden handelte. In einer Seminalplasmaprobe wurde IGFBP-5 mittels MALDI-MS identifiziert. Ein Western-Blot mit gegen IGFBP-5 generierten Antikörpern wäre ein effektives Verfahren zur Ermittlung der IGFBP-5-Aktivität im Eberseminalplasma. Die Nutzung der Proteomics-Technik zur Darstellung des Proteinmusters im Eberseminalplasma erwies sich als problematisch, da eine vertikale Streifung und die starke Intensität einzelner Spots die Identifizierung erschwerte. Es wurden mittels MALDI-TOF-TOF PSP-I und b-Mikroseminoprotein identifiziert.Um möglicherweise von PSP-I maskierte Proteine geringerer Intensität darstellen zu können, war es nötig, den PSP-I Gehalt vor der 2D-Gelelektrophorese zu verringern. Antikörper, die gegen zwei Hauptisoformen des PSP-I generiert wurden, zeigten hohe Titer gegen PSP-I und waren auch in der Lage natives PSP-I zu erkennen. Damit ist die affinitätschromatographische Abreicherung von PSP-I möglich und dadurch die Verbesserung der Trennleistung, so dass die 2D-Gelelektrophorese zur Identifizierung positiv wirksamer Proteinkomponenten im Seminalplasmas effizient genutzt werden kann.

The objective of this dissertation was to depict the structural parallels and differences of veterinary education in Germany and Great Britain from the point of view of the general framework as outlined by the European Commission. One of the main differences was the definition of the occupational area of veterinary surgeons and therefore the objectives of veterinary training. While the veterinary occupational image in Great Britain targeted to animal health care, the occupational image of veterinarians in Germany was aimed towards an "polyvalent" veterinary scientist. This difference was to be reflected strongly in the undergraduate education. Already the assessment of the number to the veterinary course presented significant differences. While in Great Britain the number of admitted candidates to the veterinary course was determined by the British veterinary schools and the professional association for veterinary surgeons, the number of applicants in Germany was calculated by a formula which was defined in the "Kapazitätsverordnung". Therefore the profession in Germany was not as protected as its counterpart in Great Britain. Major discrepancies between the University of Cambridge and the Ludwig-Maximilians Universität, Munich could be found in the admission procedures. The University of Cambridge had a specific and very complex admission procedure. Various parameters shall provide to select only the most skilled applicants to sign on the course. As the number of applicants in Germany exceeded the number of places as well, the places were distributed by a central agency, the ZVS, in accordance with the entry criteria: partly taking in consideration the marks of the Abitur and partly the date of application. Simplification of the course curriculum was the main characteristic of the Cambridge course. In order to prevent repetitions of the course content, modules were formed covering a variety of subjects. In addition the practical application of the modules was emphasised. Therefore the Cambridge course showed a reduction in overall hours and para-clinical subjects as well as an orientation towards clinical practice. The target objective to introduce the students into research work was achieved by imbedding small research projects into the course. The obligation to provide adequate training in food safety was poorly achieved by the Cambridge curriculum, when compared to the Munich one. With respect to the advanced academic training, the Munich degree of a Doktor der Veterinärmedizin could correspond to three different research degrees in Great Britain: the Certificate of Postgraduate Study, the Master of Science or the Master of Philosophy. The degree of a Doctor of Philosophy was comparable to the Tiermedizinischen Habilitation on a scientific point of view but an examination of the pedagogical skills was only performed for the Tiermedizinischen Habilitation. The differences in the continuous professional development (CPD) systems in Great Britain and Germany are mainly noticable by their organisation. While the German CPD - system was one-staged and controlled through the regional professional association, the British established a three-stage CPD system, which was controlled centrally. As this dissertation aimed to discuss the strengths and weaknesses of the veterinary education in Germany and Great Britain it had to point out on the one hand the practical and efficient clinical training in Cambridge and on the other hand the widespread training on food safety in Munich.

Thioredoxin Reductases (TR) are ubiquitously expressed Selenium-containing redox enzymes. By reducing different intracellular substrates they protect cells from oxidative stress. For mus musculus two members of the Thioredoxin Reductase gene family have been characterized so far: TR1 and TR2. Whereas the subcellular localization of TR1 is mainly cytoplasmatic, TR2 was only found in mitochondria. The protein functions of TR1 and TR2 were investigated by examining genetically engineered mice. Here I will present the establishment of a conditional TR1-knockout mouse strain and the phenotypical characterization of TR1- and of TR2-knockout mice, that have been established before. Both knockouts, TR1 and TR2, showed to be embryonically lethal. TR1 deficient mouse embryos died at day 9.5, whereas TR2 deficient mouse embryos died around day 13.0 of embryonic gestation. Total deficiency of TR1 leads to strong developmental retardation and malformations in organogenesis mostly affecting the turning of the embryo, closure of neural tube, formation of head structures and formation of somites. Thereby TR1 deficient embryos maximally reach the developmental stage of normal E8.5 wildtype embryos. Neuronal specific TR1 knockout mice show growth retardation and cerebellar hypoplasia. Starting at the postnatal age of 10-14 days they loose weight and show cerebellar ataxia and tremors. Recent results indicate that mice die at the age of approximately 4 weeks. TR2 deficient embryos can already be recognized at embryonic day E11.5 due to a smaller embryo size and paler colour. Mice are retarded in their status of organ differentiation and show malformations in heart and liver development, possibly leading to fatal heart failure or liver insufficiency. Besides that, TR2 deficient embryos show decreased proliferation rates of hematopoetic progenitor cells in the embryonic liver. Taken together these results indicate that TR1 plays an important role in embryonic growth and organogenesis. Besides, deficiency of TR2 is proposed to disturb primarily the integrity of mitochondria and as a consequence affect processes like cell proliferation and transdifferentiation – leading to embryonic death. The functions of Thioredoxin Reductases 1 and 2 in separate organ systems need to be further analyzed by using conditional ablation strategies.