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

The aim of the present study was to estimate the influence of uterine NOS-system and the sexual steroids estrogen and progesterone on the blood supply of the uterus and the ovaries. Five trotter mares were examined in total during four estrous cycles and one early pregnancy. The investigations contained color Doppler- and ultrasound recordings as soon as the extraction of blood samples and endometrial biopsies. The first cycle was medically uninfluenced and investigations were carried out on Days 0 (= ovulation), 1, 5, 11, 15 and daily during estrous, whereas in estrous only one endometrial biopsy was taken. In the second cycle luteal regression was induced on Day 5 of diestrous with the PGF2α-analogon Tiaprost (Ilirenâ, 450 mg i.m.) and in estrous ovulation was induced with hCG (Choriolutinâ, 2500 IE i.v.), when the size of one follicle reached 35 mm. Investigations were carried out in this cycle immediately before giving PGF2α and 0.5, 1, 3, 6, 12, 24, 36, 48 hours after that and then once a day up to ovulation. Endometrial biopsies were taken in each case before induction of luteolysis, 12 and 36 hours after that, before injection of hCG and immediately after ovulation. During the further two cycles the mares were treated orally with the NO donor ISDN (ISDN 40â, 30 mg, twice a day). Investigations were carried out on Days 0, 1 and 5 of the first cycle (ISDN I), as well as on Days 11, 15 and during estrous of the second cycle (ISDN II). During early pregnancy color Doppler recordings and blood samples were taken on Days 0, 1, 5, 11 and 15 of pregnancy, while endometrial biopsies were only gained on day 15. The analysis of uterine blood flow was based on the time-averaged maximum velocity (TAMV). Estrogens and progesterone were measured by an enzyme immunoassay. Nitrate concentrations were evaluated using Griess reacting. Total RNA was isolated from endo-metrial biopsies. Transcriptes encoding the estrogen receptors a and b and the endothelial as well as the inducible nitric oxide-synthase (eNOS and iNOS) were quantified by RT-PCR-analysis. The expression of eNOS-mRNA in control, as well as in the PGF2a-induced cycle, followed a consistent wavelike pattern (p < 0.05 and p < 0.0001). Both, eNOS and iNOS, showed their maximum of expression especially on Day 5 of diestrous and during estrous, when the highest levels of either progesterone or estrogen were measured. In the PGF2a-induced cycle, a significant connection between eNOS and progesterone was proved (p < 0.05). There was a positive correlation between the expression of the eNOS-mRNA and the uterine blood flow (p < 0.05) in the control cycle. In the PGF2a-induced cycle these two parameters also showed a similar cyclic pattern. The levels of estrogen-receptors in the endometrium or concentrations of estrogen in plasma were not related to the endometrial NO-synthases or to TAMV values. Plasma concentrations of nitrate were independent from the stage of estrous cycle and consequently were proved as unsuitable for the question raised here (in this case). The application of the NO donor ISDN leaded to a marked decrease of the uterine NOS-expression when compared with control cycle (p < 0.0001). An increase of uterine or ovarian perfusion during the application of ISDN was not provable (p > 0.05). In result of the biopsies on day 5 and of simultaneous ISDN application luteolysis was induced next to all mares. On day 15 of pregnancy, an increase in uterine and ovarian perfusion as well as an enhancement in iNOS-mRNA expression was observed. In conclusion, the results of this study indicate that the endometrial NO-synthases play an important role in the regulation of uterine blood supply during estrous cycle and pregnancy of the mare. Progesterone as well as estrogen seem to stimulate the endometrial expression of eNOS and iNOS, by which these hormones may indirectly influence uterine and ovarian blood flow.

Occurence of pathogenic Y. enterocolitica 4/O:3 in pork in southern Germany The prevalence of pathogenic Yersinia enterocolitica in pork products in Southern Germany was studied because no data is available of distribution of this pathogen at retail level in Germany. A total of 300 meat products containing pork from different plants were collected between May and August year 2000. These samples consist of 215 raw and 85 heat-treated products. The samples were studied with different culture methods: direct plating, overnight enrichment in TSB combined with alkali treatment, selective enrichment in MRB and ITC, and cold enrichment in TSB followed by alkali treatment. Y. enterocolitica was isolated from selective CIN agar plates. Urea-positive colonies were identified using API 20E. Y. enterocolitica isolates were bio- and serotyped, and the pathogenicity was confirmed with Congo red binding and Calcium dependence on CRMOX agar plates. Pathogenic Y. enterocolitica was recovered from raw meat products but not from heat-treated products. The isolation rate of Y. enterocolitica 4/O:3 in minced meat was 9.0%. This type was also found two times (7.4%) from raw pork. All pathogenic Y. enterocolitica isolates were belonging to bioserotype 4/O:3. Selective enrichment in ITC was shown to be the most productive method for raw meat products. No pathogenic Y. enterocolitica isolates could be recovered after non- selective enrichment even when combined with alkali treatment. These results show that raw pork can be one source of Y. enterocolitica 4/O:3 infections among humans in Southern Germany. This study also demonstrates that no pathogenic Y. enterocolitica can be found without selective enrichment.

For the first time the complete BHV-1 Schönböken genome was cloned as an infectious bacterial artificial chromosome (BAC), by inserting mini F plasmid sequences into the glycoprotein E (gE) open reading frame (ORF). DNA of the resulting BAC clone pBHV-1DgE was transfected into permissive bovine kidney cells and infectious BHV-1DgE could be recovered. Using RecE/T cloning in Escherichia coli BHV-1 genomes with a deletion of either glycoprotein G (gG) or gM or gK in addition to gE (pBHV-1DgE-gG, pBHV-1DgE-gM and pBHV-1DgE-gK) were generated. The recombinant viruses with a simultaneous deletion of gE and gG (BHV-1DgE-gG) or gE and gM (BHV-1DgE-gM), respectively, were reconstituted after transfection of manipulated BAC DNA into eukaryotic cells. However, no virus could be recovered after transfection of recombinant pBHV-1DgE-gK DNA, suggesting that gK is likewise essential for the replication of BHV-1 as demonstrated for other alphaherpesviruses. Growth properties of the other BAC derived virus mutants BHV-1DgE, BHV-1DgE-gG and BHV-1DgE-gM were analysed in vitro. The mutant viruses exhibited no markedly lowered virus titres compared to wild type strain Schönböken. However, BHV-1DgE specific virus plaques were reduced by 45% compared to BHV-1 Schönböken as assessed by plaque size measurement. Plaques sizes of BHV-1DgE-gG and BHV-1DgE-gM were reduced by 56% (BHV-1DgE-gG) and 54% (BHV-1DgE-gM). The observations made here emphasize the influence of gE, gG and gM on the BHV-1 cell-to-cell spread. Moreover, they clearly demonstrate that viral cell-to-cell spread is slightly more inhibited by a simultaneous deletion of gE and gG or gE and gM than by a single gE deletion. Comparing the plaque sizes of BHV-1DgE, BHV-1DgE-gG and BHV-1DgG it could be shown that gE and gG function independently from each other in cell-to-cell spread, because an additive and no synergistic effect was observed in the gE-gG double deletion mutant. These studies illustrate, that the propagation and manipulation of herpesviruses in bacterial systems provides the advantage of a more rapid and accurate generation and characterisation of BHV-1 deletion mutants over conventional cloning procedures. In conclusion the new technique will allow the fast generation of BHV-1 mutants as well as the investigation for their suitability as future (marker) vaccines.

population in southwestern Germany To determine the expansion of TBE infection of horses, this seroepidemiological study took place in a known endemical area, the western Bodensee/ Hochrhein region, in which the horses (n= 205) were chosen randomly. In this area the anti-body development was tracked by testing the sample three times over one year. The existence of TBE antibodies in dogs (n= 243) were also checked in the same area over the same period. A commercially obtainable ELISA (Labor Alomed, Radolfzell) was used in this anti-body determination. Random samples of the results were double checked by a neutralisation test (reference method, Baxter-Immuno, A-Orth a.d. Donau, Austria). In the first examination 48 out of 205 horses in the chosen population were tested positive. The percentage of seropositive horses in the examination area increased significantly from east to west (p= 0,001), which allowed the classification of a highly endemical area (31 % positive) and a lower endemical area (4 % positive). The anti-body titer increased significantly during the examination period. The probability of the seropositivity of a horse depended if (p= 0,001) and how often the horse visits pastures (p= 0,021). The percentage of seroreagents increased with the age of the horses (p= 0,011). A racial or sex disposition was not present. The serological examination of the dogs resulted in 71 seroreagents out of 243 (29,2 %). A geographical westward increase was noticed; however the area could not be marked out as well as could be done with the horses. This result can be explained by the higher mobility of the dogs within an area in comparison to the horses. The features: Length of fur (p= 0,015), Colour shades (p= 0,004), frequent forest contact (p= 0,001) and age (p= 0,011) are significant for dogs. A disposition for size and sex is not relevant. The probability of seropositivity of a dog increased with the features “long, fair fur” and “frequent forest contact”. The seropositivity increased with the age of the dogs; dogs younger than one year and older than 12 years had much less antibodies against the TBE virus. Zusammenfassung 131 Dogs and horses are good indicators for mapping endemical areas, because they often show seroconversion and normally have a high exposure to ticks because of the way they are kept. The proportion of the seroreagents of dogs and their average number of antibody titers in the research area were significantly higher than the average number of the. horses. Due to the result of this serological research with dogs, an endemical area can be spottet with a higher probability. Horses can then be used to narrow in the endemic areas and to find “hot spots” in low endemic areas. During the period of the research no symptoms were observed, which could give hints of a possible TBE infection, in either horses or dogs. In recent months some owners of seropositive animals have reported occurrences of bad health and temporary high temperatures which may or may not be related to TBE.

Surgical techniques in equine ophthalmology – A literature review - The objective of the presented study is to provide a comprehensive review of surgical intervention techniques and their results in the treatment of equine ophthalmologic disorders. The study surveys English, German and, to a limited degree, French literature beginning in the middle of the 19th century till today, including books, journal articles, conference proceedings and theses in the field of veterinary surgery, ophthalmology and equine diseases. Data was collected by screening of titles, keywords and bibliography of available literature and by using computer databases such as Vet-CD and Medline. Copies of the cited literature were obtained from the libraries of the Veterinary faculties in Munich, Hanover and London, the central library of the Ludwigs-Maximilians-University in Munich and the Bavarian library in Munich (Bayerische Staatsbibliothek). The chapter plan follows the anatomy of the eye and each chapter is subdivided into treatments of specific disorders. In addition chapter 1. eyelids, 3.1. conjunctiva, 3.2. third eyelid and 4. cornea include sections about specific operations performed on these structures. The horse was in the centre of surgical and ophthalmologic veterinary research and clinical work at the end of the 19th and the beginning of the 20th century - as it is reflected by the number of publications in these fields. Over the following years interest in equine ophthalmology lessened and it took till the last quarter of the 20th century to become an issue of interest again. In the meanwhile veterinary ophthalmology concentrated on small animals, especially the dog. Aetiopathogenesis and treatment of ophthalmologic disorders in the horse were hardly investigated and the specific anatomy and physiology of the equine eye were not considered to be of clinical interest. At the beginning of the 20th century reports about surgical treatment of equine ophthalmologic disorders are characterised by high case numbers, but lack statistical analysis of the data and many have in fact almost “anecdotal” form. Recent research follows today´s scientific standard methods and comprises case reports, retrospective and, to a lesser degree, prospective studies. Case numbers in this field of research are still low and comparison of different treatment methods is difficult due to the variety of disorders presented and the difference in study design. Some publications are missing out on important parameters, such as the quality of eye sight achieved after surgery; others use subjective judgement, but do not perform objective evaluation of certain parameters. There is also an obvious discrepancy between clinical prevalence of a disorder and the number of case reports dealing with it, e.g. corneal laceration, glaucoma. Some surgical techniques developed for small animals can be applied to the equine eye. However, this is not possible for all methods and the techniques may require at least species specific modifications. There are controversial discussions among the specialists in the field of equine ophthalmology with regards to indication of surgery and surgical technique, even down to the question which suture material is best. Today´s surgical techniques in equine ophthalmology seem to be far away from standardisation. More prospective and well-designed studies are desirable to provide comparable data for the different techniques in the future.

The role of thrombocyte- and leukocyte-endothelial cell-interaction in atherogenesis - an in vivo-study in the ApoE-knock-out-mouse - Platelets play a crucial role in thromboembolic complications of advanced atherosclerotic lesions but their involvement in the initiation of the atherosclerotic process in unclear. Platelet adhesion regulates secretion of intracellulary stored proinflammatory and proliferative mediators. In vitro, platelets promote the expression of inflammatory genes in endothelial cells, including adhesion receptors and chemokines suggesting a proatherogenic role of platelets. Here, we show in vivo that platelets adhere to the vascular endothelium of the carotid artery in ApoE-deficient mice prior to the development of manifest atherosclerotic lesions. Glycoprotein (GP-)Ib and GPIIb-IIIa are the predominant adhesion receptors mediating platelet adhesion to the endothelium of the carotid artery and may play a crucial role in the genesis of platelet-mediated atherosclerosis. In this experiments we could demonstrate the crucial role of these two receptors for platelet adhesion. While anti-GPIb reduced transient adhesion for 85% and permanent adhesion for 99%, anti-GPIIb-IIIa shows a 95%-reduction of permanent adherent platelets. Long–term antibody-treatment (anti-GPIb) shows by a substantial reduction of plaque area from 60% in the aorta and 81% in the carotid arterya a crucial influence of atheroprogression. Together, prolonged inhibition of platelet adhesion (with anti-GPIb) in ApoE-deficient mice profoundly inhibited arterisclerotic lesion formation. These findings establish platelets as major players in initiation of the atherogenic process and may have important implications for the development of novel anti-atherosclerotic therapies.

Untersuchungen verschiedener Regenbogenforellenstämme auf Myxobolus cerebralis, dem Erreger der Drehkrankheit der Salmoniden

Radiographic morphometry and myelography of the canine lumbar spine with regard to the diagnosis of defined ventrolateral epidural space occupying lesions. Neurologic disorders with suspicion of space occupying lesions in the vertebral canal are not always visible in myelographic standard projections (VD and Si-DeL). For these indications it might be helpful to include 45°-oblique myelograms in the radiologic procedure for a precise localisation of the involved segment or side, as verified by own results and references. For the investigation 20 euthanized small-breed (group 1), 20 middle-size-breed (group 2) and 21 large-breed dogs (group 3) were needed. The 1069 simulated ventrolateral epidural space occupying lesions in three different balloonvolume-sizes (l.) were not visible in 23% (246 of 1069 l.) of the routine VD and Si-DeL views, but in the 45°-oblique projections. In group 1 22.6% (l.= 119) of the small lesions, in group 2 58% (l.= 118) of the small and 14.4% (l.= 118) of the middle-size-lesions and in group 3 66.4% (l.= 119) of the small, 32% (l.= 119) of the middle-size-, and 10% (l.= 119) of the large lesions became diagnosed only in 45°-oblique myelograms. In comparison to the 45°-oblique myelograms in which the lesions were visible in 100% (l.= 1069), they became depicted in 68% (l.= 1069) in the VD and only in 36% (l. = 1069) in the Si-DeL view. The possibility to evaluate ventrolateral masses in 45°-oblique views and in no other projections increases significantly with the weight and body length. The most important factors are the diameter of the dural sac, the medulla spinalis and the epidural space.In all three groups of dogs measurements were made on: the vertebral canal hight and width, spinal cord hight and width, dural sac hight and width and the epidural space hight and width. Not expected morphometric differences were seen especially in group 2. In these, the ratio between the vertebral canal to the dural sac decreased from L4 to S1 faster than in the other two groups. This leads to absolutely smaller dural sacs caudal L7. The dural sacs in group 2 also end earlier in comparison to the other groups. By the examination of different breeds a significant variability of the measured diameters was observed. In conclusion the diameter of the dural sac and epidural space depends not only on the size of the dog, but also on the breed (eg. Dobermann pinsher, Foxhound, Staffordshire- and Pitbull-Terrier and Dachshound).Signifikant correlations between the end of the dural sac and the crown-rump length, the breed or the age of the dogs could not be proved.

The influence of estrogen-like substances on the gonadal development in frogs (Rana temporaria and Xenopus laevis). Ultrastructural and immunohistochemical investiga-tions on the gonads of frogs (Rana temporaria). The aim of the present thesis was the investigation and assessment of the estrogen pollu-tion of a river in South-Germany above and below a sewage plant outlet and its possible effects on the gonadal development in amphibians. In an exposure experiment with differ-ent sewage dilutions the effect on the indigenous gras frog (Rana temporaria) were com-pared with the effects on the African claw frog (Xenopus laevis). Because of the lack of relevant data in current literature it was necessary to first collect some basic data on light microscopy, ultrastructure and immunohistochemistry with reference to frogs. Furthermore the sexual differentiation of two populations of different origin were compared histologically. Characterisation of the gonads The ovaries of Xenopus laevis displayed a garland-like structure in contrast to the compact ovaries of Rana temporaria. The ovaries of both frog species were surrounded by an epi-thelium and filled with germ cells which enclosed an ovarian cavity. The oogonies were mainly found in the peripheral parts of the organ. The oocytes were characterised by a big and irregularly shaped cell nucleolus with peripherally located nucleoli. They were sur-rounded by a thin one-layered follicular epithelium. Electron microscopical examination of the ovaries of Rana temporaria showed elongated tubular mitochondria in the cytoplasm which were found exclusively in oocytes. Some of the mitochondria from subadult frogs contained yolk crystals. Additionally an accumulation of electron-tight Granule was found just below the plasma membrane, which could be a preliminary stage of the cortical granule. The testis of the frogs were enveloped by an epithelium and a tunica albuginea which al-ready showed a tubular structure. The testis from Rana temporaria and the Xenopus laevis differed in their developmental stages. The testis of juvenile Rana temporaria contained only germ cells whereas the testis of some Xenopus laevis already contained spermato-cytes and spermatozoa. The spermatocysts, characteristic of frog testis, could be seen in conjunction with the appearance of spermatocytes only. By using light microscopy two different types of germ cells in both frog species could be distinguished which probably were primary and secondary germ cells. By electron microscopical investigation of the testis of Rana temporaria the somatic cells could, on the basis of location and morphology, be differentiated in two types. The somatic cells of the first type were located inside the Tubuli seminiferi and have probably the same function as the Sertoli cells of mammals. The cells of the second type, the Leydig cells or interstitial cells, were located outside the Tubuli and were characterized by granular vesicle in the cytoplasm. With view to the sexual differentiation of Rana temporaria a comparative histological inves-tigation of the gonads of juvenile and subadult frogs of a native midland population and a high alpine population was performed. The midland population proved to be a sexually semi-differentiated species since apart from clearly male or female animals it also com-prises intersex individuals in different stages of the transformation process. The genotypi-cally male animals developed female gonads in the first place which secondly converted into testis during a hermaphrodite stage. The transformation process from female into male gonads was, on the basis of morphological criteria, classified into three stages. The highal-pin population on the other hand proved to be a sexually differentiated race. By using the Avidin-Biotin-Complex-Technique five different antibodies were tested on the gonadal tissue of juvenile and subadult Rana temporaria. The test for Laminin, a non-collagen glycoprotein, which is part of the basal membrane in mammals, resulted in a posi-tive reaction. It seems therefore that similar to Laminin in mammals a glycoprotein plays an important part in the basal membrane of frogs. α-Actin, a fibrous protein of the smooth muscles, which was detected in the Theca externa of the layer of follicle cells in different species, could be established in the blood vessel wall only and not in the layer of follicle cells. Furthermore the occurrence of a Zona pellucida by using antibodies against the por-cine glycoprotein ZP3 was investigated. The ovum including the surrounding layer of follicle cells showed a negative reaction which however did not implicitly exclude the occurrence of a glycoprotein layer with a different antigenicity. Until now the existence of a glycoprotein layer in anurans, in connection with microscopical anatomy of ovaries in Rana temporaria or other species of frogs has not been mentioned in references. The examination of the go-nadal tissue as to the occurrence of ACE (Angiotensin Converting Enzymes) turned out negative as well. Example of application With the exception of a temporarily higher concentration of alkylphenol in the beginning of the exposure, the chemical analyses revealed a relatively low degree of pollution with alcyl-phenols and steroids. The results were comparable to other results of German rivers and stayed well below other European comparative data. According to the results of this study the current level of pollution of the experimental water with estrogens does not endanger the amphibian population. The examination did not reveal any influence of the sewage on the embryonal and larval development. Furthermore, the histological investigation of the gonads in exposed and unexposed frogs with reference to the gonadal sexual differentia-tion as well as the sex ratios did not reveal significant changes. There was no correlation as to the frequency of the occurrence of intersex in the groups of exposed and unexposed frogs, neither of Xenopus laevis nor of Rana temporaria. Only the transformation process from ovaries to testis of the sexually semi-differentiated species of Rana temporaria was slowed down in the group of exposed animals in contrast to unexposed animals. The rea-son for this phenomenon could be the inhibitive influence of the low-level but more continu-ous estrogen pollution in sewage than in river water. Conversely, a link between the accel-eration of the transformation process within the group of unexposed animals and the tem-porarily higher alkylphenol level in the beginning of the exposure cannot completely be ruled out. According to references alkylphenol can cause an increase of testosterone. The semiquantitative RT-PCR detecting Vitellogenin-mRNA carried out by the Institute of Freshwater Ecology and Inland Fisheries in Berlin showed a minor increase in females of Xenopus laevis which were exposed to sewage in the ration of a 2:1 dilution in contrast to the unexposed animals. Taking into account the synergistic effects of estrogens, the in-crease could be attributed to the higher estrogen pollution of the sewage. The histopa-thological analysis for the detection of toxical effects of the sewage as well as other poten-tial influential factors provided no hints as to a possibly toxical influence of the sewage.

The human colon cancer cellline HT29 was investigated in various models regarding different criteria. The in-vivo-experiments were carried out with female SCID mice and consisted of subcutaneous cell injection, orthotopic cell injection into the cecal wall and orthotopic fixation of a tumor fragment onto the cecum. The subcutaneous experiment took 41 days; the orthotopic animal experiments were equally divided into three points of necropsy each two weeks apart. On these days tumor, liver and lung were withdrawn, fixed in 3,8% formaldehyde and analyzed histologically. In addition blood samples of all animals of the orthotopic experiments were taken on days of autopsy and the CEA (carcinoembryonic antigen) content was determined using an ELISA. The vascularization of the orthotopic primary tumors was examined by staining of CD34, i.e. number and area of the tagged vessels were ascertained. Additionally the green fluorescent protein (GFP) was studied in view of its suitability as quantifiable reporter gene in these models. Therefore not only HT29-wildtype but also HT29 cells transfected with GFP were used in vitro and in the first two in vivo assays. Advantages and disadvantages summarized: - The subcutaneous model was realized easily, measurement of the primary tumor was simple, the tumor take rate was 100 % and the laboratory animals appeared to suffer only from a relative slight amount of stress. Besides these advantages this setting cannot be used for investigations regarding metastasis because of the low number of metastases. - The orthotopic cell injection generated small, hardly measurable primary tumors, but this approach is a suitable model of metastasis because of the number of metastases detected. The technical effort and the burden for the animals exceeded that found in the subcutaneous setting but was below the effort of orthotopic fixation of a tumor fragment. - Of all investigated models the orthotopic fixation of a tumor fragment represents the model with the greatest effort. The primary tumors were big enough to be measured, but the number of metastases was too low to make statistical valuable evaluations. - The CD34 staining successfully marked the vessels of the primary tumor and facilitated a computer-assisted quantitative analysis of the vascularization of orthotopic colon tumors. It was assessed that a broad neoangiogenesis occurred at the beginning of tumor growth prior to the development of metastases. The number of metastases increased with proceeding length of time, whereas the number of vessels decreased. The continuous extension in tumor volume resulted in a necrotic tumor center so that vessels were detectable in the border area only. - The used HT29-GFP clone was not stable enough to generate sufficient fluorescence. The cells both in vitro an in vivo grew more slowly, the subcutaneous tumors showed necrotic areas and there were less metastases after orthotopic injection of GFP cells than after injection of wildtype cells. Because of the insufficient fluorescence it was not possible to execute a quantifiable analysis of metastasis. The application of GFP was not advantageous within these models. - CEA suits to be a valuable tumor marker for colon cancer in both investigated models. The CEA content in the blood samples of tumor bearing animals increased dependent on tumor burden and tumor invasiveness. A direct correlation between tumor size and CEA might be established with an improved measurement system or rather an advanced measuring of tumor volume. Due to the comparative characterization of injection and implantation techniques as well as other detailed examinations carried out for this thesis, it is possible to select suitable models for preclinical trials depending on the individual purpose.

Summary Iodine supply in dogs and cats in France The iodine content was determined for 367 dog and cat urine samples taken from different regions of France as well as random samples from one region in Ireland and Italy each. By using two mathematical equations, the estimation of the daily alimentary iodine uptake was calculated. In addition, iodine determination was performed in 53 commercial complete feed for dogs and 38 commercial complete feed for cats purchasable in France. Results were compared with data published for Germany. Furthermore in the here presented study, the stability of creatinine was investigated. It is an important parameter in the determination of the iodine content in urine. Iodine supply in dogs and cats from different regions of France and from one region of Ireland and Italy each The iodine supply of the dogs (n = 271) in the regions investigated was sufficient in 40 – 60 % of the animals. In none of the regions investigated an average iodine supply below the recommendation of 15 µg iodine/kg BW/24h could be found. These results were interpreted as a mild but evenly spread iodine deficiency. However a group of kennel dogs fed exclusively on a self prepared diet showed a too low iodine content in urine without exeption. This demonstrated the often insufficient iodine supply of self made diets; if fed regularly over a longer period of time, a iodine supplement is necessary. Concerning the iodine supply of cats (n = 96) the situation was more favorable. 80 - 90 % of the cats from the different regions had a sufficient iodine supply; in none of the regions the average iodine supply determined was lower than the recommended 21 µg/kg BW/24h. No statement could be made about regional differences. In comparison to data published for southern Germany, a similar situation of iodine supply was noted. Iodine content of certain commercial complete feed for dogs and cats in France A very broad range of iodine content could be found in commercial complete feed for dogs (26 dry- and 27 wet feed) as well as for cats (19 dry- and 19 wet feed) purchasable in France. In dog feed the maximum ( 2114 µg iodine/MJ ME) was 214 times higher than the minimum (9 µg iodine/MJ ME), while in cat feed the maximum of 1890 µg iodine/MJ ME was 210 times higher than the minimum of 9 µg iodine/ MJ ME. Large differences in iodine content could be found in different products even from the same producer. The calculated requirements for dogs of 75,6 µg iodine /MJ ME was reached by 58 % of the analysed dog feed in France; in Germany it was 56 %. The calculated requirements for cats of 95,5 µg iodine/MJ ME was reached by 50 % of the cat feed in France; in Germany it was 47 %. The situation of iodine supply in both countries in commercial dog and cat feed is almost identical. Examination of the stability of creatinine The stability of creatinine could be determined to be higher than found in literature. In dog urine it was stable for at least 14 days at room temperature.