Vetsuisse Faculty Research Articles

Natural History and Risk Factors of Hymenoptera Venom Allergy in Dogs

Hymenoptera, which includes honeybees, wasps, bumblebees, and hornets, is an order of the class Insecta, whose venom can induce anaphylactic reactions in dogs. While several studies have investigated the natural histories and risk factors of Hymenoptera venom allergy (HVA) in humans, only limited information is available on canine patients. Therefore, the aim of this study was to identify risk factors leading to severe systemic reactions (SSRs) and to explore the natural history of these patients. This was achieved with an inquiry into the case histories of 178 dogs that were stung by Hymenoptera and presented to the Vetsuisse Faculty Animal Hospital of the University of Zurich between 2018 and 2022. Dogs under two years old, dogs that weighed under 10 kg, purebred dogs, and dogs that were stung in the oral cavity were at a greater risk of developing SSRs. Almost two thirds of patients with SSRs experienced the same or worse symptoms after subsequent stings and >40% of patients with local reactions developed SSRs when stung again. Next to providing valuable clinical information about HVA in dogs, these findings strongly support the recommendation of venom immunotherapy (VIT) for patients with HVA.

Dentigerous cysts in horses: A retrospective study

SummaryBackgroundDentigerous cysts are well‐known congenital defects in horses, and the literature on this condition is extensive. Recently, a third type of dentigerous cyst, associated with an exostosis arising from the temporal bone, has been described. Today, computed tomography (CT) is often available and provides detailed information about the exact location and extent of dentigerous cysts, allowing for the description of new findings.Study designThis is a case series outlining the clinical, radiographic and computed tomographic features of dentigerous cysts in seven horses presented to the Equine Clinic at the Vetsuisse Faculty, University of Zurich, Switzerland.ObjectivesThe aim of this case series was to describe the radiographic and computed tomographic findings, and the occurrence of exostoses arising from the temporal bone, in horses with dentigerous cysts.MethodsThe medical records of the Equine Hospital at the University of Zurich were reviewed for horses admitted with dentigerous cysts between 2007 and 2023. Data collected and analysed included patient signalment, clinical history, clinical signs and their duration prior to referral, diagnostic imaging results, treatment and outcomes.ResultsThe most common location for the cysts was the base of the ear, although in one case, the maxillary sinus was involved. Of the seven cases, four were Icelandic horses. CT proved superior to standard radiography for determining the extent and precise location of the cysts, as well as for identifying dental material and exostoses in the temporal region. CT also facilitated detailed surgical planning. All cysts were surgically removed with good long‐term outcomes.Main limitationsOverall, the incidence of dentigerous cysts in horses was low. The relatively high occurrence of dentigerous cysts in Icelandic horses in this study is an interesting finding, though the small sample size calls for further research.ConclusionsTwo of the cases in this series were similar to a recently described variant of a ‘temporal dentigerous cyst associated with an exostosis in the temporal region’ and were closely connected to the bony structure and draining tract.

Navicular bone fractures in horses: Prognosis after conservative and surgical treatment

The aim of this retrospective study is to describe and compare conservative and surgical treatment of navicular fractures in horses. An attempt is made to identify critical points that can favorably influence the prognosis of this orthopedic disease. All horses treated for a navicular fracture at the Equine Clinic, Vetsuisse Faculty, University of Zurich between 2005 and 2017 were included in this study. The severity of lameness at initial examination, radiographic assessment, hoof conformation, treatment (conservative or surgical), complications and outcome were determined from the medical records. Conservative and surgical treatment consisted of stable rest, a controlled exercise program and therapeutic orthopedic shoeing. During surgical treatment, fracture reduction was also carried out with a cortical screw. Computer assisted surgery were used in five horses and computer tomography in three horses. Follow-up examinations included clinical and radiographic examinations. The outcome was divided into three categories: 1 = very good; 2 = good; 3 = poor. Twelve horses met the inclusion criteria; Four horses were treated conservatively and eight were treated surgically. After conservative treatment, two horses (50 %) had a very good outcome and two (50 %) had a good outcome. After surgical treatment, four horses (50 %) had a very good outcome and four (50 %) had a poor outcome. Overall, 67 % of horses had a very good or good outcome, although radiographic signs of bone healing was not present in any of these cases. Various complications were identified, such as the fracture of a screw, the fragmentation of the small navicular bone fragment, the development of osteoarthrosis in the coffin joint and progressive podotrochosis. This study shows that the prognosis of navicular fractures is generally cautious and that degenerative changes to the navicular apparatus worsen the prognosis. In the present study, surgical treatment did not improve the prognosis of navicular fractures despite the intrasurgical use of three-dimensional imaging. However, technical advances could reduce the complication rate in the future.

Findings Related to Cerebrospinal Fluid and Central Nervous System Disorders in Small Ruminants-A Retrospective Study on Sheep and Goats.

Small ruminants often suffer from central nervous system (CNS) disorders, and cerebrospinal fluid (CSF) analysis can be used as a diagnostic tool in this regard. In small animals and cattle, specific CSF patterns have been defined for specific disease categories. No data exist regarding CSF results obtained from small ruminants and their association with certain CNS diseases. The objective of this study was to retrospectively investigate CSF findings obtained from sheep and goats and to identify possible CSF patterns associated with disease categories. CSF samples and medical records from 44 sheep and 27 goats were included in this study. All animals were presented to the Veterinary Teaching Hospital Zurich of the Veterinary Teaching Hospital Zurich of the Vetsuisse Faculty of the University of Zurich between 2003 and 2016 and had either a confirmed CNS diagnosis or showed CSF changes without a specific CNS diagnosis. Mixed mononuclear pleocytosis was the most common CSF pattern in sheep (25%), followed by monocytic pleocytosis (21%). Lymphocytic pleocytosis was most frequently found in goats (37%). In 75% of sheep and 56% of goats, infectious CNS diseases were diagnosed, with listeriosis being the most common infectious disease in both species, followed by parasitic disorders (nematodiasis and coenurosis). The cytologic CSF patterns in small ruminants are mainly based on the increased presence of monocytic and lymphocytic cells with variable quantitative expression, whereas neutrophilic pleocytosis and cytoalbuminologic dissociation were rare findings. Infectious diseases of bacterial origin were the most common underlying causes for CSF alterations in sheep and goats, followed by parasitic disorders. The pleocytosis type is not helpful for differentiating disease types.

Examinations of cattle births with a special focus on Coxiella burnetii

Cattle births can carry the risk of transmissible and zoonotic diseases. The focus of the present study was the excretion of Coxiella (C.) burnetii during cattle births. Small ruminants are considered as the main reservoir of C. burnetii. Cattle are often subclinical carriers and their role as potential reservoir has not been fully elucidated until now, although the excretion of Coxiella has been demonstrated during cattle birth. The study recorded all births, caesarean sections and one abortion in 40 cattle at the ruminant clinic of the Vetsuisse Faculty in Bern in the study period from March 2019 to March 2020. A placenta -, milk - and fecal sample was examined for antigen diagnostics using polymerase chain reaction (PCR). In addition, a serum sample was analyzed to detect C. burnetii-specific antibodies. Antigen and/or antibodies (placenta, n=8/9; milk, n=2/9; faeces, n=1/9; serology n= 3/9) were detected in 22,5 % of the cows (n=9/40) without the presence of specific clinical symptoms. It is essential to sensitize contact persons to this zoonosis, since Coxiella can trigger Q-fever in humans.

Investigated regional apparent diffusion coefficient values of the morphologically normal feline brain.

Diffusion-weighted imaging (DWI) MRI is increasingly available in veterinary medicine for investigation of the brain. However, apparent diffusion coefficient (ADC) values have only been reported in a small number of cats or in research settings. The aim of this study was to investigate the ADC values of different anatomical regions of the morphologically normal brain in a feline patient population. Additionally, we aimed to assess the possible influence on the ADC values of different patient-related factors, such as sex, body weight, age, imaging of the left and right side of the cerebral hemispheres and white vs grey matter regions. This retrospective study included cats undergoing an MRI (3T) examination with DWI sequences of the head at the Vetsuisse Faculty of the University Zurich between 2015 and 2021. Only cats with morphologically normal brains were included. On the ADC maps, 10 regions of interest (ROIs) were manually drawn on the following anatomical regions: caudate nucleus; internal capsule (two locations); piriform lobe; thalamus; hippocampus; cortex cerebri (two locations); cerebellar hemisphere; and one ROI in the centre of the cerebellar vermis. Except for the ROI at the cerebellar vermis, each ROI was drawn in the left and right hemisphere. The ADC values were calculated by the software and recorded. A total of 129 cats were included in this study. The ADC varied in the different ROIs, with the highest mean ADC value in the hippocampus and the lowest in the cerebellar hemisphere. ADC was significantly lower in the white cerebral matter compared with the grey matter. ADC values were not influenced by age, with the exception of the hippocampus and the cingulate gyrus. ADC values of different anatomical regions of the morphologically normal feline brain in a patient population of 129 cats in a clinical setting are reported for the first time.

Effect of early administration of tranexamic acid on ongoing haemorrhage in dogs with non-surgically treated haemoabdomen.

Tranexamic acid (TXA) is an antifibrinolytic drug used for the prophylaxis and treatment of haemorrhage of various origin. This retrospective study investigated the effect of TXA on ongoing bleeding in dogs with nonsurgically treated haemoabdomen. The study population consisted of 48 dogs treated in the period 2009-2020 at the Small Animal Clinic of the Vetsuisse Faculty of Zurich. Twenty-eight of 48 dogs were treated with 20 mg/kg TXA IV within 3h of diagnosis of haemoabdomen. Dogs treated with and without TXA were monitored over 48 hours for signs of ongoing haemorrhage. Ongoing haemorrhage was defined as an increase in abdominal fluid accumulation, a decrease in haematocrit of >5% over time or need for surgical exploration after at least 12 hours of medical treatment. Transfusion requirements, cumulative amount of fluid therapy, heart rate, respiratory rate, temperature, systolic and mean arterial pressure, estimate of abdominal fluid identified by FAST analysis, venous haematocrit, abdominal haematocrit, serum albumin, serum lactate and thrombocyte count were extracted from patient records at 6, 12, 24 and 48 hours after diagnosis of haemoabdomen. Groups were comparable at presentation, however dogs of the TXA group showed a significantly lower abdominal haematocrit at presentation (37 vs 45%, P=0,034) and a higher fluid accumulation (P=0,019), both persisting over time. None of the outcome parameters for ongoing haemorrhage was significantly different between groups. Transfusion requirement was low and similar in both groups. Of interest, none of the 16 dogs undergoing thromboelastometry showed hyperfibrinolysis at presentation. We conclude that other mechanisms than antifibrinolytic therapy was responsible for cessation of bleeding in the majority of patients.

Metastatic cornual melanoma in a Valesian copperneck goat

AbstractA 10‐year‐old, neutered, male Valesian copperneck goat was presented to the Clinic for Ruminants, Vetsuisse Faculty, University of Bern for a chronic wound at the base of the right horn first noticed 3 weeks before presentation. Clinical examination revealed a firm mass with ulcerations and malodorous discharge at the base of the right horn, and a duller sound on percussion of the right frontal sinus. Radiography revealed a soft tissue opacity filling the right cornual diverticulum of the frontal sinus. Upon wound debridement, tissue of grey to black discoloration was noticed and sent in for histopathological examination, which confirmed the presence of a melanoma. Subsequent ultrasonography of the liver and radiography of the thorax revealed no sign of metastatic disease. Given the poor prognosis, the goat was euthanased, and postmortem examination revealed the presence of multiple metastatic lesions in the regional lymph nodes.

SARS-CoV-2 infections in cats, dogs, and other animal species: Findings on infection and data from Switzerland

The pandemic with the novel coronavirus (SARS-CoV-2) has led to infections and deaths worldwide. Apart from humans, certain animal species are susceptible to the viral infection. Spillover between humans and animals is favored by close contact; thus, surveillance of animals is an important component to fight the pandemic from a One Health perspective. The Clinical Laboratory of the Vetsuisse Faculty Zurich has been investigating SARS-CoV-2 infections in animals since the beginning of the pandemic. In November 2020, the first SARS-CoV-2 positive Swiss cat was reported to the World Organisation for Animal Health (OIE-WAHIS). The cat showed respiratory signs and lived in a COVID-19 affected household. By now, over 500 natural SARS-CoV-2 infections have been recorded in animals worldwide. A prevalence study on SARS-CoV-2 infections in dogs and cats was carried out together with clinics from Germany and Italy during the first wave of the pandemic (March-July 2020). Among the tested 1137 animals, only one cat and one dog were positive. The prevalence of infection in dogs and cats presented to veterinary clinics was low, even in pandemic hotspot regions. However, recent studies that focused on animals in COVID-19 households found a higher prevalence of infection. A study is currently underway that specifically collects samples from pets from Swiss COVID-19 affected household and collects data on human-animal interaction.

Falcons From the United Arab Emirates Infected With Chlamydia psittaci/C abortus Intermediates Specified as Chlamydia buteonis by Polymerase Chain Reaction.

Chlamydiaceae are obligate intracellular bacteria with a broad host range. Several studies have found chlamydial species that are genetically intermediate between Chlamydia psittaci and Chlamydia abortus in various avian species. One of these intermediate Chlamydia species, found in a red-shouldered hawk (Buteo lineatus), was recently classified as a new species Chlamydia buteonis. This newly described Chlamydia species has, so far, only been reported in hawks exhibiting clinical signs of conjunctivitis, dyspnea, and diarrhea. In the present study, fecal samples of 5 gyrfalcons (Falco rusticolus), 3 gyr/peregrine falcon hybrids (Falco rusticolus × Falco peregrinus), and 15 falcons of unknown species presented to falcon clinics on the Arabian Peninsula were shipped to the Vetsuisse Faculty, University of Zurich (Zurich, Switzerland), for examination for the presence of Chlamydiaceae. A step-wise diagnostic approach was performed to identify the chlamydial species involved. Chlamydiaceae were detected in 21/23 falcons by a family-specific real-time quantitative PCR (qPCR). Further identification with a 23S ribosomal RNA-based microarray assay and 16S conventional PCR and sequencing yielded inconclusive results, indicating the presence of an intermediate Chlamydia species. Because none of the falcons tested positive for Chlamydia psittaci by specific qPCR, all 23 samples were subjected to a Chlamydia buteonis-specific qPCR, which was positive in 16/23 samples. Detailed information regarding clinical history was available for 8 falcons admitted to a falcon clinic in Dubai, United Arab Emirates. Six of those birds that were presented to the clinic because of loss of performance and poor general condition, including vomiting and diarrhea, were positive for C buteonis. In 2 birds without clinical disease signs admitted for a routine health examination, 1 was positive for C buteonis, and 1 was negative. It is yet unknown whether Chlamydia buteonis causes disease in birds, but the findings in this study indicate that Chlamydia buteonis may be an infectious pathogen in falcon species.

Evaluation of agreement and correlation of results obtained with MRI-based and macroscopic observation-based grading schemes when used to assess intervertebral disk degeneration in cats.

To evaluate agreement in results obtained with an MRI-based grading scheme and a macroscopic observation-based grading scheme when used to assess intervertebral disk (IVD) degeneration in cats. 241 MRI and 143 macroscopic images of singular IVDs in 44 client-owned cats (40 cadaveric and 4 live). Singular images of IVDs were obtained of live cats admitted for treatment of suspected neurologic disease (MRI images of IVDs) and of cadavers of cats euthanized for reasons unrelated to spinal disease (MRI and macroscopic images of IVDs) at the Small Animal Hospital, Vetsuisse Faculty, Zurich, Switzerland, between January 12, 2015, and October 19, 2015. The IVD images were randomized and evaluated twice by 4 observers for each grading scheme. Inter- and intraobserver reliability for the grading schemes was assessed with Cohen weighted κ analysis. Agreement and correlation between results obtained with the 2 grading schemes were determined with Cohen weighted κ and Spearman correlation coefficient (ρ) analyses, respectively. Inter- and intraobserver agreement between results was substantial to almost perfect (mean weighted κ, 0.66 to 0.83 and 0.71 to 0.86, respectively) for the MRI-based grading scheme and moderate to substantial (mean weighted κ, 0.42 to 0.80 and 0.65 to 0.79, respectively) for the macroscopic observation-based grading scheme. Between the 2 grading schemes, agreement in results was moderate (mean ± SE weighted κ, 0.56 ± 0.05), and the correlation was strong (ρ = 0.73). Results indicated that the MRI-based and macroscopic observation-based grading schemes used in the present study could be used reliably for classifying IVD degeneration in cats.

Comparison of 3D‐assisted surgery and conservative methods for treatment of type III fractures of the distal phalanx in horses

SummaryThe aim of this retrospective study was to compare the outcome of conservative methods and 3D‐assisted surgery for treatment of type III fractures of the distal phalanx with regard to recovery time and the development of osteoarthritis (OA) in the distal interphalangeal joint (DIPJ). The medical records of all horses with type III fracture of the distal phalanx referred to the Equine Department, Vetsuisse Faculty, University of Zurich, between 1992 and 2016 were reviewed. The severity of lameness at initial examination, radiographic evaluation, treatment (conservative, group A; 3D‐assisted surgery, group B), complications, outcome and recovery time were determined. Follow‐up examinations included clinical and radiographic examinations. Of 33 horses, 15 received conservative treatment and 18 underwent surgery. Eleven of the 15 (73.3%) horses in group A returned to their intended use and four were subjected to euthanasia or remained chronically lame. The median recovery time was 240 days (95% CI, 180–374). Thirteen of 15 (86.7%) horses developed OA of the DIPJ within 5 months of the fracture. In group B, 16 of 17 (94.1%) horses returned to their intended use, one horse remained chronically lame, and one horse was subjected to euthanasia because of unrelated reasons. The median recovery time was 139 days (95% CI, 120–270), and seven horses (38.9%) developed OA of the DIPJ within 5 months of the fracture. Overall, the screws had to be removed in five fluoroscopic‐assisted surgery cases (three because of implant infection and two because of severe lameness), in one computer‐assisted surgery case due to severe lameness and in one computed tomography‐assisted surgery case because of implant infection. In conclusion, there was no significant difference in time for recovery of type III fractures of the distal phalanx between the two groups, but surgical treatment led to significantly fewer cases of OA in the DIPJ as determined by subjective radiographic evaluation (P = 0.015).

Membrane-based therapeutic plasma exchange in dogs: Prescription, anticoagulation, and metabolic response.

BackgroundTherapeutic plasma exchange (TPE) is used increasingly in small animals to remove circulating large molecular products such as antibodies, pathogenic proteins, and protein‐bound toxins. Specific, efficient, and safe protocols need to be developed.Hypothesis/ObjectivesTo describe the technique of membrane‐based TPE, the resulting physiological and metabolic changes, and to define an adequate regional citrate anticoagulation protocol.AnimalsThirty‐four dogs treated with TPE (2011‐2017).MethodsRetrospective review of all TPE treatments performed at the Vetsuisse Faculty, University of Bern, identified through a search of the institutional database for extracorporeal treatments.ResultsSixty‐four treatments were performed, resulting in 1.0 plasma volume exchange (range, 0.4‐1.1). Replacement fluids included fresh frozen plasma (12%‐100% volume), colloids (0%‐52%), human albumin (0%‐41%), and saline (0%‐70%). Anticoagulation was performed with regional citrate (n = 24), systemic heparinization (n = 2), or combined (n = 38). Main relevant laboratory changes included a 24.7% decrease in total proteins (interquartile range, 16.7‐31.4; P < .001), 53% in fibrinogen (−30 to 63; P = .009), 36% in bilirubin (13‐43, P = .02), 9.0% in urea (0.7‐15.7; P < .001), and 4.5% in creatinine (−6.6 to 10.6; P = .006). Citrate accumulation was evidenced in all dogs, more pronounced in those with renal but not with hepatic impairment. Maximal tolerable citrate rates were estimated as 5.5 and 9.0 μmol/kg/min for treatments in dogs with and without renal impairment, respectively. Complications were observed in 22 treatments (34%) and were fatal in 2 dogs.Conclusions and Clinical ImportanceTherapeutic plasma exchange causes metabolic and biochemical alterations. Understanding these effects makes possible to anticipate most complications and to improve safety of the procedure.

Pierre M. Montavon (1949-2018).

I remember very well a difficult period at the Vetsuisse Faculty University of Zurich, Switzerland, when Pierre Montavon, already Professor of small animal surgery, felt cheated by the board of directors of the faculty. The financial sources were shortened for his clinic and a team room was assigned to another clinic. Pierre took out his pirate flag and it waved from the window of his office for some weeks, demonstrating that he would not accept the decision, but would follow his own way.

Food intake and energy expenditure in growing cats with and without a predisposition to overweight.

Overweight and obesity are multifactorial diseases caused by an imbalance in energy metabolism. An underlying genetic predisposition is often a factor in these conditions. In the cat breeding family of the Institute of Animal Nutrition at the Vetsuisse Faculty, University of Zurich, a segregating overweight phenotype with a genetic contribution was observed. From this breeding family, 26 kittens were followed from birth up to 8months of age. During this time, food intake was measured using an automatic feeding station, and energy expenditure was investigated using indirect calorimetry at the ages of 4 and 6months. Dual-energy X-ray absorptiometry (DEXA) was performed and blood glucose, leptin and insulin were measured at the ages of 4, 6 and 8months. The kittens were also weighed daily for the first 2weeks of life, every second day until weaning and once per week until 8months of age. The body condition score (BCS) was evaluated monthly between 2 and 8months of age. The main finding of this study is that a predisposition to overweight is connected to a higher food intake early in life, with no significant alterations in energy expenditure. The leptin blood levels were related to body fat percentage, and insulin sensitivity did not seem to be affected.

Epidemiology of fractures: The role of kick injuries in equine fractures.

Fractures occur commonly in equids and often are associated with complications and a poor outcome. There are no reports on the epidemiology of fractures in a heterogeneous equine population. To study the epidemiology of fractures in a heterogeneous equine population, focusing on differences between fractures resulting from a kick and fractures, resulting from other causes and investigating predictors for recovery. Retrospective case series. Data of all equids presented to the Equine Department, Vetsuisse Faculty, University of Zurich between 1990 and 2014 and diagnosed with a fracture were reviewed and those with a known cause were included in this study. Mann-Whitney and chi-squared tests were used to compare recovery rates of fractures resulting from a kick and fractures resulting from other causes, and a logistic regression was carried out for multivariate analysis of the most important factors affecting recovery. Here, 1144 cases fulfilled the inclusion criteria. Of all fractures (with a known cause), 43.6% were the result of a kick from another equid. Kicks often produced open fractures (44.7%) that involved bones of the limbs (85.6%). Overall recovery was 70.1%. Logistic regression showed that high-grade lameness accompanying the fracture and severe comminution negatively affected recovery. The equids in this study were drawn from a referred population, which likely precluded the inclusion of both minor fractures and catastrophic fractures that necessitated immediate euthanasia. Moreover, many cases were excluded because the cause of the fracture could not be determined from the patient record. Kicks are the most common cause of fractures in a heterogeneous equine population and measures to reduce the incidence of kicks are necessary in group-housing systems.

Veterinary parasitology teaching – Ten years of experience with the Vetsuisse curriculum

Pursuant to the Joint Declaration by 29 European education ministers in June 1999 in the city of Bologna, Italy, the so-called ‘Bologna Process’ was officially introduced at the Vetsuisse Faculty (Universities of Zurich and Berne) in Switzerland in 2007. The long-term goal of restructuring the study programmes was to create a common European Higher Education Area (EHEA), with uniform and clearly defined standards for degrees (“diplomas”). Accordingly, the Vetsuisse curriculum was organised as a 3-year Bachelor and a 2-year Master study program. For the final Federal examination in veterinary medicine, both programs and a master thesis have to be completed. Parasitology, as a subject, is introduced with selected examples in the ecology course during the first academic year. The second and third years of the Bachelor program comprise non-organ-centred (NOC) and integrated organ-centred (OC) course modules, respectively. In the NOC modules, parasitology is taught in consecutive courses, focussing on topics including occurrence, biology, pathogenesis, clinical manifestations, diagnostics and the strategic principles of therapeutic and prophylactic interventions against major veterinary and zoonotic parasites. This syllabus is complemented with live demonstrations as well as practical laboratory exercises. Lecture notes, with defined learning objectives, are based on the textbook “Parasitology in Veterinary Medicine” which is available free of charge to students as an on-line edition in German. Furthermore, students review relevant parasitoses in the diagnostic context of OC case presentations. In another module, immunological aspects of parasitic diseases are elaborated on group sessions, supported through the use of specialist literature. The two-year Master program is divided into a core syllabus for all students, and elective subjects are chosen from six areas of specialisation (three each with clinical or non-clinical focus). Within the clinically focused specialisations, interactive teaching of control strategies against parasitoses of companion and farm animals is the focus. Students specialising in ‘Pathobiology’ experience a deep immersion in parasitology. Learning objectives are verified in different test formats. E-learning tools, including a learning management on-line platform, allow interactive student training in coproscopic diagnostic techniques and in arachno-entomology and provide case-oriented teaching. Since an aptitude test limits the number of first-year students in veterinary medicine in Switzerland (80 in Zürich, 70 in Berne), the conditions for students and teachers are similar each year. The fragmentation of teaching in veterinary parasitology, the reduction of the number of diagnostic exercises and clinically oriented day-1-skills pertaining to the control of parasitoses are critically commented upon.

Direct approach to the nasal cavity through a bone flap for the treatment of a large nasal cyst

SummaryA 21‐year‐old Warmblood mare was referred to the Equine Department, Vetsuisse Faculty, University of Zurich, because of recurrent unilateral nasal discharge 3 months after partial removal of a large cyst from the left maxillary and frontal sinuses. Endoscopic, radiographic and computed tomographic examinations showed that the remnant of the cyst, which originally had extended from the left maxillary and frontal sinuses into the left nasal cavity, had expanded and was obliterating the left middle nasal meatus. A direct surgical approach to the cyst through the left nasal and maxillary bones rostral to the facial crest was chosen, which allowed evaluation and removal of the entire cyst. Endoscopic examination 3 days post operatively showed no remnants of the cyst, and the mare was discharged in good health. Re‐examination one year later showed no recurrence of the cyst.

Joint histogram analysis of histology and micro computed tomography to reveal the performance of bone-grafting materials

Event Abstract Back to Event Joint histogram analysis of histology and micro computed tomography to reveal the performance of bone-grafting materials Bert Müller1, 2, Bernd Ilgenstein1, Anja K. Stalder1, Natalia Chicherova1, Hans Deyhle1, Georg Schulz1, Stefan Stübinger2, 3, Brigitte Von Rechenberg3 and Simone E. Hieber1 1 University of Basel, Biomaterials Science Center, Switzerland 2 University Hospital Basel, Surgery, Switzerland 3 University of Zurich, Vetsuisse Faculty ZH, Switzerland In oral surgery, bone-grafting materials have been applied to provide sufficient bone for successful implant insertion. Although autologous bone is still the gold standard, commercially available bone grafts play an important role because of the limited availability of autologous bone and the wish of patients and clinicians to avoid discomfort related to the harvesting procedure. As the bone grafts can be fully integrated into the remodelling process, the tissue can regenerate completely. The commercially available bone graft materials differ in composition and structure, and significant differences in their behaviour can be expected. A clinical comparison of several grafting materials is rare. To this end, we harvested trepanned biopsies exactly at the site of implant placement from eleven patients treated with Bio-Oss® (Geistlich Pharma AG, Wolhusen, Switzerland), BoneCeramic (Institute Straumann AG, Basel, Switzerland) with an absorbable collagen membrane (Bio-Gide® Geistlich Biomaterials, Wolhusen, Switzerland) and easy-graftÔ (SUNSTAR Degradable Solutions AG, Schlieren, Switzerland). These cylindrically shaped specimens were non-destructively visualized using micro computed tomography in absorption contrast mode. Subsequently, hematoxylin and eosin stained histological images were obtained. Dedicated software was developed to identify the counterpart of the two-dimensional histological slices in the three-dimensional micro computed tomography data, cf. Fig. 1 and ref[1]. It was validated by the manual search of a medical expert. Once satisfactory congruence was reached, a joint histogram was generated to segment the tissues, i.e. old and newly formed bone as well as soft tissues and the remaining bone-grafting material. The differences of the bone-grafting materials in density and composition are clearly reflected in their local X-ray attenuation. As not only conventional micro computed tomography but also the synchrotron radiation-based technique was applied, the density resolution or contrast of the data was sufficient to discriminate bone in different mineralization stages and bone-grafting materials in various stages of degradation. Nevertheless, intensity-based segmentation can prove challenging, since the X-ray attenuation coefficients of the components overlap. The combination with histology, however, allowed identifying many anatomical features and the grafting material, which can neither be obtained from the histological nor from the high-resolution, high-contrast X-ray tomography data alone[2]. The volume of newly formed bone and of the remaining bone-grafting materials was determined. A direct comparison of the materials implanted in patients is, however, still questionable and the number of cases has to be increased significantly. Therefore, our study is preliminary and methodically oriented.

Vaccines and drugs against Neospora caninum, an important apicomplexan causing abortion in cattle and other farm animals

Vaccines and drugs against Neospora caninum, an important apicomplexan causing abortion in cattle and other farm animals Andrew Hemphill, Joachim Müller Institute of Parasitology, Vetsuisse Faculty, University of Bern, Bern, Switzerland Abstract: The apicomplexan parasite Neospora caninum represents an important abortion-causing parasite in cattle. The economic impact of neosporosis has led to considerable investments to develop vaccines that would prevent infection and abortion. Live-attenuated vaccines have been shown to confer some protection against N. caninum infection, but may cause problems due to regulatory issues and other drawbacks. Therefore, efforts have been undertaken to develop recombinant subunit vaccines based on antigens involved in adhesion/invasion or other parasite–host cell interaction processes. Concerning chemotherapeutical agents, the currently known arsenal of active drugs that act against N. caninum is limited to a small number of compounds with suitable in vitro properties including low inhibition constants, parasitocidal effects, and low cytotoxicity. For in vivo studies, mostly small laboratory animal models that mimic cerebral infection, acute disease, and fetal loss upon infection during pregnancy have been applied for the assessment of vaccines or drug candidates. However, only a small number of recombinant vaccines and drug candidates have met the expectations, and small laboratory models for neosporosis need to be standardized in order to be able to compare the results of different laboratories. Few vaccines and compounds have made it into trials involving ruminant models such as cattle or sheep, including live-attenuated vaccines and the anticoccidial drug toltrazuril. We here summarize the current status of vaccine and drug development for neosporosis. Keywords: neosporosis, anti-infective agents, chemotherapy, immunotherapy, vaccine, drug target