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Regenerative bone implants should be completely replaced by new bone within a period of time corresponding to the growth rate of native bone. To meet this requirement, suitable biomaterials must be biodegradable and promote osteogenesis. The combination of slowly degrading but osteoconductive calcium phosphates (CPs) with rapidly degrading and mechanically more resilient magnesium phosphates represents a promising material class for this purpose. In order to create the best possible conditions for optimal implant integration, microporous calcium magnesium phosphate (CMP) cements were processed using 3D powder printing. This technique enables the production of a defect-adapted implant with an optimal fit and a high degree of open porosity to promote bone ingrowth. Four different compositions of 3D printed CMP ceramics were investigated with regard to essential properties of bone implants, including chemical composition, porosity, microstructure, mechanical strength, and cytocompatibility. The ceramics consisted of farringtonite (Mg 3 (PO 4 ) 2 ) and stanfieldite (Ca 4 Mg 5 (PO 4 ) 6 ), with either struvite (NH 4 MgPO 4 ·6H 2 O) or newberyite (MgHPO 4 ·3H 2 O) and brushite (CaHPO 4 ·2H 2 O) as additional phases. The CMP materials showed open porosities between 13 and 28% and compressive strengths between 11 and 17 MPa, which was significantly higher, as compared with clinically established CP. The cytocompatibility was evaluated with the human fetal osteoblast cell line hFOB 1.19 and was proven to be equal or to even exceed that of tricalcium phosphate. Furthermore, a release of 4-8 mg magnesium and phosphate ions per mg scaffold material could be determined for CMPs over a period of 21 d. In the case of struvite containing CMPs the chemical dissolution of the cement matrix was combined with a physical degradation, which resulted in a mass loss of up to 3.1 wt%. In addition to its beneficial physical and biological properties, the proven continuous chemical degradation and bioactivity in the form of CP precipitation indicate an enhanced bone regeneration potential of CMPs., (Creative Commons Attribution license.)

Objective: This study aims to compare the Modified Maquet Procedure (MMP) with the Tibial Plateau Leveling Osteotomy (TPLO) using long-term follow-up examinations over the period of more than one year (∅ 3,15 years) by clinical examination, radiographic assessment of osteoarthritis progression, and gait analysis by treadmill examination. Additional aim is to review the influence of surgeons' experience in TPLO technique., Material and Methods: This clinical study included 67 stifle joints of 50 dogs of different breeds between 20 and 40 kilograms body weight that were treated by TPLO (n = 48) or MMP (n = 19) following the rupture of the cranial cruciate ligament. The TPLO group was further divided into a group operated by two experienced surgeons (TPLO1, n = 25) and a second group operated by several surgeons with different experience (TPLO2, n = 23). Following a post-operative time period of more than one year in the least (mean, 3.15 ± 1.21 years) orthopedic and radiographic examinations as well as separate unilateral and bilateral gait analyses were conducted. In addition, gait analysis data were compared with an orthopedically healthy control group., Results: No significant and clinically relevant differences were observed between the 3 groups in the results of their orthopedic examination.Osteoarthritis progression showed similar values in all 3 surgical groups. On average per year this feature was slightly but statistically significantly lower in the TPLO2 group in comparison to the TPLO1 and MMP groups.Gait analysis during walking exhibited significant differences in bilateral ruptures at the Peak Vertical Force and the Vertical Impulse, especially when compared to the healthy control group. Stance phase duration did not show any significant differences. At trot, no significant differences were found between the 3 surgical groups., Conclusion: Both surgical techniques achieved good clinical, radiological, and gait analysis results in the 3 groups at long-term follow-up, even when compared with a healthy control group., Clinical Relevance: MMP can be considered a rapid feasible alternative to the established TPLO method also bearing satisfactory results in dogs. The degree of the surgeon's experience does not seem to influence the outcome., Competing Interests: Es besteht kein Interessenkonflikt der Autoren., (Thieme. All rights reserved.)

In recent years, dentistry has steadily gained more prominence in veterinary medicine, including exotic and wild animal medicine. It is known that dental diseases are among the most common diseases in captured big cats. However, so far, there is no standardized method for dental radiography in these animals. Therefore, this study aimed to develop a standardized procedure for the systematic radiographic examination of the teeth in big cats. In total, 34 big cats, including 21 lions and 13 tigers, of different ages were examined. Animals that needed treatment for known dental diseases and those that had to be anesthetized for other medically necessary procedures and dental health status examinations were included. Intraoral dental radiographs were captured with digital imaging plates designed for intraoral dental radiography in horses. Based on the intraoral dental radiography procedures used in domestic cats, both the bisecting angle technique and parallel technique were used. A hemisphere model originally developed for horses was used to describe the path and position of the x-ray beam as accurately as possible. The results demonstrated that it was possible to completely image all the teeth of big cat dentition on seven radiographs using the described method. This method can be used to acquire high-quality intraoral dental radiographs in big cats, aiding in the quick and reliable diagnosis of dental diseases.

Introduction: Measurement of torsional deformities and varus alignment in the canine femur is clinically and surgically important but difficult. Computed tomography (CT) generates true three-dimensional (3D) information and is used to overcome the limitations of radiography. The 3D CT images can be rotated freely, but the final view for angle measurements remains a subjective variable decision, especially in severe and complex angular and torsional deformities. The aim of this study was the development of a technique to measure femoral angles in a truly three-dimensional way, independent of femoral positioning., Methods: To be able to set reference points in any image and at arbitrary positions of the CT series, the 3D coordinates of the reference points were used for mathematical calculation of the angle measurements using the 3D medical imaging Software VoXim ® . Anatomical reference points were described in multiplanar reconstructions and volume rendering CT. A 3D bone-centered coordinate system was introduced and aligned with the anatomical planes of the femur. For torsion angle measurements, the transverse projection plane was mathematically defined by orthogonality to the longitudinal diaphyseal axis. For varus angle measurements, the dorsal plane was defined by a femoral retrocondylar axis. Independence positioning was tested by comparison of angle measurement results in repeated scans of 13 femur bones in different parallel and two double oblique (15/45°) positions in the gantry. Femoralvarus (or valgus), neck version (torsion), and inclination angles were measured, each in two variations., Results: Resulting mean differences ranged between -0.9° and 1.3° for all six determined types of angles and in a difference of <1° for 17 out of 18 comparisons by subtraction of the mean angles between different positions, with one outlier of 1.3°. Intra- and inter-observer agreements determined by repeated measurements resulted in coefficients of variation for repeated measurements between 0.2 and 13.5%., Discussion: The introduction of a bone-centered 3D coordinate system and mathematical definition of projection planes enabled 3D CT measurements of canine femoral varus and neck version and inclination angles. Agreement between angular measurements results of bones scanned in different positions on the CT table demonstrated that the technique is independent of femoral positioning., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Brühschwein, Schmitz, Zöllner, Reese and Meyer-Lindenberg.)

Objective: Aim of the study was to collect data concerning the use of antibiotics (AB) in dogs and cats in veterinary practices and clinics in Bavaria, Germany. It was evaluated, whether changes in the use of AB since the amendment of the Verordnung über Tierärztliche Hausapotheken (TÄHAV, German Regulation on the Veterinary In-house Pharmacy) in March 2018 could be documented., Material and Methods: Using 2 anonymous online surveys in 2017 and 2020, veterinarians treating dogs and cats in Bavaria were questioned about their usage of AB and their assessment of the current antimicrobial resistance situation. The results of both surveys were evaluated statistically and compared with each other., Results: While in 2017 a total of 238 questionaries were evaluated, 160 could be included in 2020. The three most commonly used antibiotics for systemic therapy were Amoxicillin/Clavulanic acid (74.8 % of veterinarians), Enrofloxacin (56.7 %) and Amoxicillin (53.4 %) in 2017; and Amoxicillin/Clavulanic acid (88.8 %), Amoxicillin (67.5 %) and Metronidazole (33.8 %) in 2020, respectively. The participating veterinarians stated that their overall use of 3 rd and 4th generations cephalosporins (from 20.2 % of veterinarians in 2017 to 9.4 % in 2020, p = 0,005) as well as fluoroquinolones (from 80.3 % to 33.1 %, p < 0.001) had significantly declined. In 2020, the choice of AB in veterinarians was affected by legal requirements (83.8 %), tolerability (81.3 %), way of application (76.9 %), acceptance by the patient (70.0 %), and frequency of application (64.4 %), with the last parameter being significantly more important to veterinarians working in a practice (83.8 %, p = 0.004) than to veterinarians in a clinic., Conclusion: Veterinarians report a significantly reduced usage of fluoroquinolones and 3 rd and 4th generation cephalosporines in dogs and cats compared to 2017. These changes in prescribing practice could be a consequence of the amendment of the TÄHAV, which dictates a prohibition of rededication as well as an obligation for microbial sensitivity testing for these AB classes., Clinical Relevance: Legal restrictions could have a positive influence on the amount and type of antibiotics used and therefore help to prevent antimicrobial resistance., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

Due to the positive effects of magnesium substitution on the mechanical properties and the degradation rate of the clinically well-established calcium phosphate cements (CPCs), calcium magnesium phosphate cements (CMPCs) are increasingly being researched as bone substitutes. A post-treatment alters the materials' physical properties and chemical composition, reinforcing the structure and modifying the degradation rate. By alkaline post-treatment with diammonium hydrogen phosphate (DAHP, (NH 4 ) 2 HPO 4 ), the precipitation product struvite is formed, while post-treatment with an acidic phosphate solution [e.g., phosphoric acid (PA, H 3 PO 4 )] results in precipitation of newberyite and brushite. However, little research has yet been conducted on newberyite as a bone substitute and PA post-treatment of CMPCs has not been described in the accessible literature so far. Therefore, in the present study, the influence of an alkaline (DAHP) or acid (PA) post-treatment on the biocompatibility, degradation behavior, and osseointegration of cylindrical scaffolds ( h = 5.1 mm, Ø = 4.2 mm) produced from the ceramic cement powder Ca 0.75 Mg 2.25 (PO 4 ) 2 by the advantageous manufacturing technique of three-dimensional (3D) powder printing was investigated in vivo . Scaffolds of the material groups Mg225d (DAHP post-treatment) and Mg225p (PA post-treatment) were implanted into the cancellous part of the lateral femoral condyles in rabbits. They were evaluated up to 24 weeks by regular clinical, X-ray, micro-computed tomographic (µCT), and histological examinations as well as scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) analysis and compared with tricalcium phosphate (TCP). All materials showed excellent biocompatibility and rapid osseointegration. While TCP degraded only slightly, the CMPCs showed almost complete degradation. Mg225d demonstrated significantly faster loss of form and demarcability from surrounding bone, scaffold volume reduction, and significantly greater degradation on the side towards the bone marrow than to the cortex than Mg225p. Simultaneously, numerous bone trabeculae have grown into the implantation site. While these were mostly located on the side towards the cortex in Mg225d, they were more evenly distributed in Mg225p and showed almost the same structural characteristics as physiological bone after 24 weeks in Mg225p. Based on these results, the acid post-treated 3D powder-printed Mg225p is a promising degradable bone substitute that should be further investigated., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Kowalewicz, Waselau, Feichtner, Schmitt, Brückner, Vorndran and Meyer-Lindenberg.)

Objective: The aim of the study was to investigate the awareness for the breed-related brachycephalic obstructive airway syndrome (BOAS) and the occurrence of other breed-typical diseases within the framework of an online survey for pug owners., Material and Methods: A digital questionnaire for owners was created, distributed via social media and subsequently evaluated., Results: The questionnaire was completed by 1220 pug owners. According to the owners, 32 % (344/1073) of the animals that did not undergo airway dilatation surgery show slight and 3 % (34/1073) show distinct breathing sounds when at rest. 86 % (326/378) of the owners perceive these breathing sounds as "normal, breed-specific" and 14 % (51/378) consider them as sign of "disease". 20 % (210/1073) of the animals are considered "somewhat" and 5 % (57/1073) "frequently tired and quickly short of breath" after a small amount of time. 24 % (245/1220) of all animals suffer from ocular diseases, 10 % (122/1220) from skin diseases and 11 % (134/1220) from spinal diseases, among others., Conclusion: The survey shows that with 67 % (814/1220) more than half of the pug owners perceive clinical signs of BOAS and/or other breed-specific diseases in their animals, however, a large proportion consider these as being non-problematic., Clinical Relevance: The present study reveals that the animals' clinical limitations associated with brachycephaly are oftentimes not perceived as being pathologic and are hence underestimated by the owners., Competing Interests: Die Autoren bestätigen, dass kein Interessenskonflikt besteht., (Thieme. All rights reserved.)

This study was performed to provide a description of the normal anatomy of the canine hindlimb veins using helical CT images. The studies of 30 dogs that underwent CT venography with a 64-slice helical CT scanner were retrospectively reviewed. The dogs were positioned in a head-first prone or head-first supine body position. A topogram CT scan was performed from the pelvic limbs cranial to the iliac wings to the tips of the paws. Bolus-tracking software was used for the dual-phase angiogram, and contrast medium was administered in a cephalic vein. The venous phase was scanned after a delay time of a few seconds after the arterial phase in a caudocranial direction. Three-dimensional images were generated using maximum intensity projections and volume rendering technique. Representative images of three of the 30 dogs were selected and anatomic structures labelled., (© 2022 The Authors. Anatomia, Histologia, Embryologia published by Wiley-VCH GmbH.)

Objective: To collect kinetic and kinematic data on the back movement in healthy dogs in comparison to chondrodystrophic dogs following hemilaminectomy while walking and trotting., Material and Methods: Gait analysis on the back movement was obtained from 19 healthy dogs and 21 chondrodystrophic dogs following hemilaminectomy procedure in consequence to disc herniation in the thoracic or lumbar region., Results: In transverse and sagittal planes the group of surgically treated dogs showed a higher range of motion (ROM) throughout the spine while walking and trotting. The difference in back movement depended on the region of the hemilaminectomy (thoracic, thoracolumbar, or lumbar). Operated dogs showed a significantly higher weight distribution towards their front limbs. When comparing the weight distribution among the hind limbs, there was a decreased Peak Vertical Force (PVF) and Vertical Impulse (VI) on the side corresponding to the hemilaminectomy., Conclusions: Following hemilaminectomy, dogs displayed increased instability within their spine, which - depending on the region and side of the hemilaminectomy - affected the back movement in different ways. Weight bearing was generally shifted away from the hind limb of the affected side, and towards the front limbs., Clinical Relevance: Even though hemilaminectomy has an effect on the back movement of dogs, it seems not to have relevant influence of quality of life., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

Objective:  The aim of this study was to investigate whether small- to medium-sized dogs with a naturally occurring unilateral hindlimb lameness show the same compensatory changes in ground reaction forces as large-breed dogs and how the changes are displayed compared with healthy small- to medium-sized dogs., Study Design:  Small- to medium-sized dogs ( n  = 15) and large-breed dogs ( n  = 16) with unilateral rupture of the cranial cruciate ligament were examined. The kinetic parameters peak vertical force and vertical impulse of the two groups were compared with each other and compared with healthy Beagles ( n  = 15) and with healthy Labrador Retrievers ( n  = 17), respectively., Results:  The healthy Beagle group showed a significantly higher weight loading on the forelimbs compared with the healthy Labrador group. The affected groups in comparison with the corresponding healthy groups showed a higher load on the non-affected body half and a significant lower weight bearing on the affected limb. Comparing the two affected groups, no significant difference could be found., Conclusion:  Despite a substantially different initial situation regarding weight distribution of the examined small- to medium-sized dogs and large dogs, a unilateral hindlimb lameness leads to the same compensatory changes (cranial and lateral shift of the body mass centre)., Competing Interests: None declared., (Thieme. All rights reserved.)

Objective:  The aim of the study was to investigate the kinetic and kinematic changes in the stifle after a tibial plateau levelling osteotomy (TPLO) with a postoperative tibia plateau angle (TPA) of either 6 or 1 degrees., Study Design:  Biomechanical ex vivo study using seven unpaired canine cadaver hindlimbs from adult Retrievers.Hinge plates were applied and a sham TPLO surgery was performed. Motion sensors were fixed to the tibia and the femur for kinematic data acquisition. Pressure mapping sensors were placed between femur and both menisci. Thirty per cent bodyweight was applied to the limbs with the stifle in 135 degrees of extension. Each knee was tested with intact cranial cruciate ligament (CCL), deficient CCL, 6 degrees TPLO and 1degree TPLO., Results:  Transection of the CCL altered kinematics and kinetics. However, comparing the intact with both TPLO set-ups, no changes in kinematics were detected. After 1 degree TPLO, a significant reduction in the force acting on both menisci was detected ( p  = 0.006)., Conclusion:  Tibial plateau levelling osteotomy restores stifle kinematics and meniscal kinetics after transection of the CCL ex vivo . The contact force on both menisci is reduced significantly after TPLO with a TPA of 1 degree. Increased stifle flexion might lead to caudal tibial motion., Competing Interests: None declared., (Thieme. All rights reserved.)

Objective:  Magnification error is always present in radiography and calibration is necessary, if high accuracy is required in pre-surgical planning. The goal of this study was to verify the use of self-made markers and calibration techniques and to establish guidelines for magnification correction., Study Design:  We evaluated and compared spherical and linear markers of different sizes with focus on practicability, accuracy and precision. Markers were placed on foam pads or attached to flexible arms., Results:  Vertical marker deviation of 1 cm from the anatomical reference point corresponded to ∼1% of magnification error in our setting. Marker placement along the horizontal plane showed no significant magnification in the periphery of the radiograph. All markers showed good accuracy and the commercial spherical marker with a flexible segment arm had the best results regarding practicability., Conclusion:  Our study suggests that marker type is not solely responsible for usability and accuracy but also the type of fixation. In the absence of a calibration marker, calculation of the magnification factor using a measurement tape during radiography is equally reliable. Use of a fixed averaged calculated calibration factor showed poor agreement compared with the marker calibration, probably due to variability in size of the animals. In conclusion, if precision matters, use of a calibration marker, which could be purchased or self-made, is advised., Competing Interests: None declared., (Thieme. All rights reserved.)

Objectives: Survey concerning the situation of small animal anesthesia in Europe and assessment of the compliance with the guidelines of the AVA (American Society of Anesthesiologists) and the DVG specialty group VAINS (Veterinary Anesthesia, Intensive Care, Emergency Medicine, and Pain Management)., Material and Methods: A link to an online survey with questions concerning anesthesia management (topics include demographics, equipment, monitoring, thermal management, pre-anesthetic examination, anesthetic protocol, and others) was sent to small animal practitioners in several countries., Results: A total of 767 evaluable questionnaires came from Germany (n = 343), Austria (n = 216), Switzerland (n = 83), the United Kingdom (n = 38), France (n = 25), Hungary (n = 25), Scandinavia (n = 23), and "other countries" (n = 11). On average, 91 % of respondents complied with the AVA guideline and 58 % complied with the VAINS specialty group guideline even before its publication. Practices/clinics with higher staff possessed superior equipment, and practices/clinics performing higher numbers of anesthesias per week were more likely to implement "good preliminary examination.", Conclusion and Clinical Relevance: Although the guidelines were found to be implemented to a certain degree, the presented study reveals a potential for optimization of the anesthesia regime in many practices/clinics, e. g. by improving the equipment or allowing for better use of present apparatus., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

Two female intact Labrador Retriever dogs (6 and 3 months of age, respectively) presented with a history of urinary incontinence. In both dogs, abdominal ultrasound revealed evidence of a unilateral ectopic ureterocele. Diagnosis of ureteral ectopia was established urethrocystoscopically by visualization of the ureteral orifice in the urethra, and an intramural course was confirmed via retrograde contrast fluoroscopy. Ectopic ureteral orifices were stenotic in both dogs. Cystoscopic- and fluoroscopic-guided laser ablation of the ectopic ureter were performed with a Hol:YAG laser. Following the procedure, both dogs were fully continent without any medical treatment. Cystoscopic- guided laser ablation of ureteroceles was effective and safe in these 2 dogs. Thus, this minimally invasive technique for the treatment of ectopic ureteroceles provides an alternative to surgical intervention., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

Radius and ulna fractures can be detected in dogs with an incidence of 18.0% and occur more frequently in toy breeds with increased complication rates. The reasons for the predisposition and the increased complication rate of antebrachial fractures in toy breeds are not yet fully understood. The aim of this study was to research the associated mechanisms by investigating the trabecular structure parameters (BV/TV (%), Tb.N (mm -1 ), Tb.Th (mm), Tb.Sp (mm), Conn. D (mm -3 ), DA) and the cortical bone density (Mean Density (mg HA/ccm)) for toy breeds and small dogs of other breeds using microcomputed tomography and to identify the differences between both groups. A total of 70 forearms, originating from toy breeds (n = 36) and small dogs of other breeds (n = 34) were evaluated by microcomputed tomography. The results of this study showed a lower bone volume fraction (BV/TV), more (Tb.N) but thinner trabeculae (Tb.Th) with greater separation (Tb.Sp) and decreased diaphyseal cortical density (Mean Density) in toy breed dogs. This could thus contribute to the increased risk of antebrachial fractures in toy breeds. Within the group of toy breeds inhomogeneous results were observed, whereby the values of the Chihuahuas deviated. This breed had significantly thinner trabeculae (Tb.Th) with a greater trabecular separation (Tb.Sp), lower bone volume fraction (BV/TV) and significantly lower diaphyseal cortical density (Mean Density). These parameters could therefore indicate an increased antebrachial fracture and complication risk, especially in Chihuahuas., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Introduction: For the regeneration of large volume tissue defects, the interaction between angiogenesis and osteogenesis is a crucial prerequisite. The surgically induced angiogenesis by means of an arteriovenous loop (AVL), is a powerful methodology to enhance vascularization of osteogenic matrices. Moreover, the AVL increases oxygen and nutrition supply, thereby supporting cell survival as well as tissue formation. Adipose-derived stem cells (ADSCs) are interesting cell sources because of their simple isolation, expansion, and their osteogenic potential. This study targets to investigate the coimplantation of human ADSCs after osteogenic differentiation and human umbilical vein endothelial cells (HUVECs), embedded in a vascularized osteogenic matrix of hydroxyapatite (HAp) ceramic for bone tissue engineering. Materials and Methods: An osteogenic matrix consisting of HAp granules and fibrin has been vascularized by means of an AVL. Trials in experimental groups of four settings were performed. Control experiments without any cells (A) and three cell-loaded groups using HUVECs (B), ADSCs (C), as well as the combination of ADSCs and HUVECs (D) were performed. The scaffolds were implanted in a porous titanium chamber, fixed subcutaneously in the hind leg of immunodeficient Rowett Nude rats and explanted after 6 weeks. Results: In all groups, the osteogenic matrix was strongly vascularized. Moreover, remodeling processes and bone formation in the cell-containing groups with more bone in the coimplantation group were proved successful. Conclusion: Vascularization and bone formation of osteogenic matrices consisting of ADSCs and HUVECs in the rat AVL model could be demonstrated successfully for the first time. Hence, the coimplantation of differentiated ADSCs with HUVECs may therefore be considered as a promising approach for bone tissue engineering.

An 8-year-old primiparous Labrador Retriever bitch was presented to the clinic 46 hours following the delivery of 2 vital and one stillborn puppy due to an increase of vaginal discharge. At the veterinary clinic, the dog spontaneously delivered an additional healthy puppy without any obstetric support. The findings of the general and gynaecological examinations as well as results of blood analyses were within normal limits. This case shows that extremely prolonged whelping process may be a rare but possible phenomenon in bitches. However, it is recommended to re-evaluate dam and fetuses regularly in case the inter-whelping interval exceeds the normal time span in order to recognize further signs of dystocia and induce obstetric support when clinically indicated., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

Degradable bone substitutes made of magnesium alloys are an alternative to biological bone grafts. The main advantage is that they can be manufactured location- and patient-specific. To develop and scale appropriate implants using computational models, knowledge about the mechanical properties and especially the change in the properties during the degradation process is essential. Therefore, degraded open-pored implants were investigated using scanning electron microscope and nanoindentation to find their material composition and mechanical properties. Using both techniques the correlation of the material composition and the average modulus was determined. It could be shown that the average modulus of the degradation layer is distinctly lower than that of the base material. The local average modulus of degrading implant highly depends on the magnesium concentration and the accumulation of elements from the environment. A decrease in magnesium concentration leads to a decrease in the average modulus. Thus, the degrading implant had a lower stiffness than the initial structure., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

There is increasing prevalence of digital diagnostic imaging in veterinary medicine with a progressive need to use medical imaging software. As Digital Imaging and Communications in Medicine (DICOM)-viewers for veterinary use do not require medical device approval in many countries, freeware viewers might be a practical alternative. The aim of this study was to identify and evaluate free DICOM-viewer software for veterinary purposes. The functionality and user-friendliness of various DICOM-viewers from the internet were analyzed and compared. Inclusion criteria for the evaluation were free availability, PACS (picture archiving and communication system)-connectivity, and stand-alone and client-based software. Based on this, eight viewers were found: Ginkgo CADx, Horos, K-PACS, MAYAM, MITO, OsiriX Lite, RadiAnt, Synedra personal. In these DICOM-viewers, 14 core tools were tested and rated on a score from 1 to 10 by multiple observers with different levels of training, using studies of four imaging modalities. Criteria were functionality and user-friendliness. For each viewer, the total number of a predefined set of 47 important tools was counted. The ranking based on functionality and user-friendliness of 14 core tools (mean score in brackets) was as follows: 1. Horos/OsiriX Lite (8.96), 2. RadiAnt (8.90), 3. K-PACS (8.02), 4. Synedra (7.43), 5. MAYAM (6.05), 6. Ginkgo CADx (5.53), 7. MITO (3.74). The DICOM-viewers offered between 20 and 44 tools of the predefined important tool set and are sufficient for most veterinary purposes. An increasing number of tools did not necessarily impair user-friendliness, if the user interface is well designed. Based on the results of this study, veterinarians will find suitable free DICOM-viewers for their individual needs. In combination with PACS-freeware, this allows veterinary practices to run a low-budget digital imaging environment.

Objective: Evaluation the development of perioperative body temperature while administrating a combination of acepromazine and metamizol (AM) versus anesthesia with acepromazine (A) alone., Material and Methods: In this prospective, quasi-randomized controlled study 20 dogs undergoing standardized tibial plateau leveling osteotomy were alternatingly assigned to group A or group AM (n = 10 each). The patients' body temperature values were recorded from the time of premedication up to its post-surgical return to reference values., Results: Body temperature decreases during anesthesia in both groups were comparable (p = 0.12). Postoperatively on the other hand, temperature development differed significantly between the two groups (p = 0.0455). In 6 dogs of the group AM, body temperature continued to decrease following extubation prior to returning to normothermic values., Conclusion: Intraoperatively, all patients developed hypothermia, regardless of the investigated anesthetic medication administered. Postoperatively, patients not receiving metamizol reached normothermia more rapidly., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (© Georg Thieme Verlag KG Stuttgart · New York.)

Mesenchymal stem cells (MSC) are multipotent cells, which are able to differentiate into various cell types of the body, as for example in osteogenic, chondrogenic, adipogenic and myogenic directions. In human medicine, the application of stem cells represents a well-established clinical procedure already applied for several decades. Addition-ally, in veterinary medicine, the stem-cell field is a rapidly growing sector for clinical use, particularly in horses. Recently, this treatment moda lity has also been commonly applied in dogs. The main field of application are diseases of the musculoskeletal system. Furthermore MSC are predominantly used for the treatment of lameness because of osteoarthritic changes of the large joints. In veterinary medicine, MSC are mainly isolated from bone marrow or adipose tissue. This artic le provides an overview of the removal site, isolation, characterisation and application of MSC. Moreover, studies available in the litera ture concerning the therapy of orthopaedic diseases in the dog using MSC are presented., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (Georg Thieme Verlag KG Stuttgart · New York.)

Objective: The aim of the first part of the present study was to specify risk factors for the development of adventitious bursae on the limbs of weaning and finishing pigs., Material and Methods: In total, 192 pigs were examined weekly, recording the following parameters: general condition, number, size and localization of adventitious bursae on the limbs and sternum, gait and claws., Results: Adventitious bursae can occur at 13 positions on the limbs or sternum. These adventitious bursae were already evident when pigs were moved to the nursery. The prevalence of adventitious bursae increased constantly from weaning to slaughter. At the age of 24 weeks, 97.8 % of all investigated pigs displayed adventitious bursae (aged 4 weeks: 25.5 %; aged 12 weeks: 67.6 %). Heavier pigs had significantly more and larger adventitious bursae than lighter pigs of the same age. Furthermore, heavier pigs retrieved feed from the automatic feeder less frequently but ate larger amounts each time. In addition, pigs with poorer gait displayed significantly more adventitious bursae. In 95.6 % of all investigated pigs, claw lesions were evident at slaughter. The general condition was unaffected by adventitious bursae., Conclusion and Clinical Relevance: Referring to the results of the present study and the general function of bursae protecting underlying structure against pressure, there is no indication that adventitious bursae affect the animal welfare in terms of the sensation of pain. Influenced by various factors, adventitious bursae develop with high prevalence and number per animal over the course of the life of pigs and can be described as a technopathy. Because of the exposure of adventitious bursae, there is a risk to become an ulcerated bursa of degree three in relation to injuries., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (Georg Thieme Verlag KG Stuttgart · New York.)

Objectives:  To evaluate negative pressure wound therapy (NPWT) for treatment of complicated wounds in dogs., Study Type:  Prospective randomized clinical study MATERIALS AND METHODS:  Dogs ( n  = 26) undergoing open-wound treatment were randomly assigned to one of two groups: Group A ( n  = 13) NPWT; Group B ( n  = 13) silver-coated foam dressing. Pairs of patients were matched based on wound conformation, localization, and underlying cause and compared in terms of duration of previous treatment, development of wound size (wound planimetry), time to closure, bacterial bio-burden and complications. Wound dressing changes were performed every 3 days during the first 9 days of therapy for both groups. Statistical analysis was performed., Results:  Pre-treatment signalment and bacterial status were comparable between groups. Total time to closure was significantly ( p  = 0.018) shorter in Group A (14.2 days) compared with Group B (28.6 days), and wound planimetry on days 3, 6 and 9 showed significant greater reduction in total wound area for Group A at all-time points ( p  < 0.05). Furthermore, wounds in Group A showed less progression of local infection than did wounds in Group B ( p  = 0.01)., Conclusion:  NPWT-treated wounds showed faster closure, improved macro-deformation and less local signs of infection., Competing Interests: None., (Georg Thieme Verlag KG Stuttgart · New York.)

Objective: To evaluate the bacterial contamination rate and to compare the efficacy of polyhexanide, cold argon plasma and saline at reducing bacterial bio-burden in dog bite wounds., Material and Methods: Dogs with bite-wound injuries were included when surgical debridement was pursued with subsequent treatment using either polyhexanide-biguanide lavage (A), cold argon plasma treatment (B) or saline lavage (C). Culture swabs were taken after debridement as well as after lavageor argon treatment. Statistical analysis was performed using the chi-square test., Results: A total of 40 dogs were enrolled in the study (A: n = 12; B: n = 10; C: n = 18). The majority of injuries were minor and 87.5% of patients had positive bacterial culture results pre-lavage, with 19.8% of isolates classified as multidrug resistant. A reduction in wound bioburden was achieved in 8/12 patients in group A, 5/10 patients in group B and 14/18 patients in group C. Complete decontamination was achieved in 5/12 patients in group A, 2/10 in group B and 9/18 in group C. None of these differences were statistically significant nor associated with the development of complications., Conclusion: No statistically significant differences were detected between the treatment groups; however, the cold argon plasma treatment provided the least effective decontamination., Clinical Relevance: Bite wounds yield a high rate of bacterial contamination, with increasing multidrug-resistance rates. Based on these preliminary results, no superior effect was detected for lavage using polyhexanidebiguanide or cold argon plasma., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (Schattauer GmbH.)

A unicameral bone cyst in the proximal humerus of a 3-year-old Norwegian forest cat was diagnosed by dynamic contrast-enhanced magnetic resonance imaging, surgical exploration, and histopathology. Surgical curettage and incorporation of bone cement led to full recovery. An osteosarcoma developed at the surgical site 17 months later. Thoracic radiographs showed pulmonary lesions consistent with metastasis.

Aims: Rapid blood vessel ingrowth in transplanted tissue engineering constructs is the key factor for successful incorporation, but many potential patients who may use engineered tissues suffer from widespread diseases that limit the capacity of neovascularization (e.g. diabetes). Thus, in vivo vascularization analyses of tissue-engineered constructs in angiogenically affected organisms are required., Methods: We therefore investigated the in vivo incorporation of collagen-coated and cell-seeded poly-L-lactide-co-glycolide scaffolds in diabetic B6.BKS(D)-Lepr(db)/J mice using repetitive intravital fluorescence microscopy over a time period of two weeks. For this purpose, scaffolds were seeded with osteoblast-like or bone marrow mesenchymal stem cells and implanted into the dorsal skinfold chambers of diabetic and non-diabetic (C57BL/6) mice., Results: Apart from slightly increased inflammatory parameters, diabetic mice showed significantly reduced capillary densities compared with non-diabetic animals from day 6 onward. In line with previous studies, more densely meshed microvascular networks were demonstrated in cell-seeded than in collagen-coated scaffolds from day 6 onward within the single groups (diabetic and control)., Conclusions: A large number of patients who suffer from systemic diseases that affect angiogenesis would profit from tissue engineering. Therefore, the challenge for the clinical introduction of tissue-engineered constructs will be to overcome the decreased angiogenesis in diabetic organisms., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Magnesium alloys are the focus of research as resorbable materials for osteosynthesis, as they provide sufficient stability and would make surgery to remove implants unnecessary. The new degradable magnesium alloy ZEK100 was developed to improve the stability and corrosion resistance by alloying with zinc, rare earth metals and zirconium. As the implants were degraded to only a limited extent after 6 months implantation in a previous in vivo study the present study was conducted to evaluate the long-term degradation behaviour and biocompatibility in the same animal model over 9 and 12 months. Five rabbits each with intramedullary tibia implants were examined over 9 and 12 months. Three legs were left without an implant to serve as negative controls. Numerous examinations were performed in the follow-up (clinical examinations, serum analysis, and radiographic and in vivo micro-CT investigations) and after death (ex vivo micro-CT, histology, and implant analysis) to assess the in vivo degradation and biocompatibility. It could be shown that favourable in vivo degradation behaviour is not necessarily associated with good biocompatibility. Although ZEK100 provided a very high initial stability and positive biodegradation, it must be excluded from further biomedical testing as it showed pathological effects on the host tissue following complete degradation., (Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Biocompatibility and degradation of magnesium sponges (alloy AX30) with a fluoride (MgF(2) sponge, n = 24, porosity 63 ± 6 %, pore size 394 ± 26 μm) and with a fluoride and additional calcium-phosphate coating (CaP sponge, n = 24, porosity 6 ± 4 %, pore size 109 ± 37 μm) were evaluated over 6, 12 and 24 weeks in rabbit femurs. Empty drill holes (n = 12) served as controls. Clinical and radiological examinations, in vivo and ex vivo μ-computed tomographies and histological examinations were performed. Clinically both sponge types were tolerated well. Radiographs and XtremeCT evaluations showed bone changes comparable to controls and mild gas formation. The μCT80 depicted a higher and more inhomogeneous degradation of the CaP sponges. Histomorphometrically, the MgF(2) sponges resulted in the highest bone and osteoid fractions and were integrated superiorly into the bone. Histologically, the CaP sponges showed more inflammation and lower vascularization. MgF(2) sponges turned out to be better biocompatible and promising, biodegradable bone replacements.

Background: Most studies on biodegradable magnesium implants published recently use magnesium-calcium-alloys or magnesium-aluminum-rare earth-alloys.However, since rare earths are a mixture of elements and their toxicity is unclear, a reduced content of rare earths is favorable. The present study assesses the in vivo biocompatibility of two new magnesium alloys which have a reduced content (ZEK100) or contain no rare earths at all (AX30)., Methods: 24 rabbits were randomized into 4 groups (AX30 or ZEK100, 3 or 6 months, respectively) and cylindrical pins were inserted in their tibiae. To assess the biodegradation μCT scans and histological examinations were performed., Results: The μCT scans showed that until month three ZEK100 degrades faster than AX30, but this difference is leveled out after 6 months. Histology revealed that both materials induce adverse host reactions and high numbers of osteoclasts in the recipient bone. The mineral apposition rates of both materials groups were high., Conclusions: Both alloys display favorable degradation characteristics, but they induce adverse host reactions, namely an osteoclast-driven resorption of bone and a subsequent periosteal formation of new bone. Therefore, the biocompatibility of ZEK100 and AX30 is questionable and further studies, which should focus on the interactions on cellular level, are needed.

Background: In recent years magnesium alloys have been intensively investigated as potential resorbable materials with appropriate mechanical and corrosion properties. Particularly in orthopedic research magnesium is interesting because of its mechanical properties close to those of natural bone, the prevention of both stress shielding and removal of the implant after surgery., Methods: ZEK100 plates were examined in this in vitro study with Hank's Balanced Salt Solution under physiological conditions with a constant laminar flow rate. After 14, 28 and 42 days of immersion the ZEK100 plates were mechanically tested via four point bending test. The surfaces of the immersed specimens were characterized by SEM, EDX and XRD., Results: The four point bending test displayed an increased bending strength after 6 weeks immersion compared to the 2 week group and 4 week group. The characterization of the surface revealed the presence of high amounts of O, P and Ca on the surface and small Mg content. This indicates the precipitation of calcium phosphates with low solubility on the surface of the ZEK100 plates., Conclusions: The results of the present in vitro study indicate that ZEK100 is a potential candidate for degradable orthopedic implants. Further investigations are needed to examine the degradation behavior.

Magnesium alloys have been in the focus of research in recent years as degradable biomaterial. The purpose of this study was the biomechanical characterisation of MgCa0.8-screws. The maximum pull out force of screws was determined in a synthetic bone without corrosion and after fixed intervals of corrosion: 24, 48, 72 and 96 h. This in vitro study has been carried out with Hank's solution with a flow rate corresponding to the blood flow in natural bone. A maximum pull out force (F(max)) of 201.5 ± 9.3 N was measured without corrosion. The biomechanical parameter decreased by 30% after 96 h in corrosive medium compared to the non-corrosion group. A maximum load capacity of 28 ± 7.6 N/h was determined. Our biomechanical data suggests that this biodegradable screw provides a promising bone-screw-fixation and has great potential for medical application.

The aim of this study was to compare the biomechanical properties of degradable magnesium calcium alloy (MgCa0.8) screws and commonly used stainless steel (S316L) screws and to assess the in vivo degradation behavior of MgCa0.8. MgCa0.8 screws (n=48) and S316L screws (n=32) were implanted into both tibiae of 40 adult rabbits for a follow-up of 2, 4, 6 and 8 weeks. This resulted in a testing group of MgCa0.8 (n=12) and S316L (n=8) screws for each follow-up. Uniaxial pull-out tests were carried out in an MTS 858 Mini Bionix at a rate of 0.1 mm s(-1). For degradation analysis of MgCa0.8 in vivo micro-computed tomography (μCT) was performed to determine the volume of metal alloy remaining. Retrieved MgCa0.8 screws were analysed for degradation by determination of weight changes, scanning electron microscopy and energy dispersive X-ray analyses. No significant differences could be noted between the pull-out forces of MgCa0.8 and S316L 2 weeks after surgery (P=0.121). Six weeks after surgery the pull-out force of MgCa0.8 decreased slightly. In contrast, the S316L pull-out force increased with time. Thus, significantly higher pull-out values were detected for S316L from 4 weeks on (P<0.001). The volume and weight of MgCa0.8 gradually reduced. A corrosion layer, mainly composed of oxygen, magnesium, calcium and phosphorus, formed on the implants. Since MgCa0.8 showed good biocompatibility and biomechanical properties, comparable with those of S316L in the first 2-3 weeks of implantation, its application as a biodegradable implant is conceivable., (Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Purpose: Tissue expanders lead to changes in the underlying bone and can cause bone resorption. We investigated whether the insertion of mechanical devices that distribute the load on the bone can influence these effects., Materials and Methods: A total of 28 Lewis rats were assigned to 1 of 4 groups. Hydrogel expanders were placed subcutaneously either directly on the calvaria, on titanium mesh, or on a titanium plate. The fourth group of rats served as the controls. The bone quality and thickness were assessed beneath, and at the periphery of, the expanders using micro-computed tomography and histologic examination., Results: Micro-computed tomography images were obtained before and 21 days after insertion. The images revealed a significant decrease in hydroxyapatite density beneath the expanders in the group with only expanders. This decrease was reduced with the use of titanium mesh and completely prevented with the use of titanium plates. Histologic examination revealed a significant decrease in bone density and marked lacunae beneath the hydrogel expanders in the group with only expanders. In contrast, the titanium mesh decreased the size of the lacunae, and the titanium plates completely prevented both the formation of lacunae and the decrease in bone thickness., Conclusion: The bone resorption caused by hydrogel expanders can be diminished using titanium mesh and completely prevented by the insertion of a titanium plate., (Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

The knowledge of the radiation exposure of the staff involved in X-ray examinations is one precondition for an optimisation of radiation protection. Hence the radiation exposure of the staff during X-ray examinations of dogs and cats was investigated in the Clinic for Small Animals. The study includes at least ten measurements for each of thirteen X-ray examinations of a dog and four of a cat. The equivalent doses of eye lens, thyroid, chest, hands, gonads, and lower leg were measured using TLD (LiF:Mg,Cu,P). The maximum values of 44.3 and 48.3 microSv were measured on the eye lens and the thyroid, respectively. The median and mean values of the equivalent doses on the seven measuring positions with the exception of eye lens (6.0 microSv) are lower than 5 microSv per radiograph. More than 95% of the equivalent doses on chest, hands, gonads, and lower leg are smaller than 2 microSv. Particularly eye lenses and thyroid are exposed to measurable doses. Altogether the radiation exposure of the staff is relatively low. Hence a manual fixation of animals is justifiable if the fundamental rules of radiation protection are observed.

In this study the quality of digital and analog radiography in dogs was compared. For this purpose, three conventional radiographs (varying in exposure) and three digital radiographs (varying in MUSI-contrast [MUSI = MUlti Scale Image Contrast], the main post-processing parameter) of six different body regions of the dog were evaluated (thorax, abdomen, skull, femur, hip joints, elbow). The quality of the radiographs was evaluated by eight veterinary specialists familiar with radiographic images using a questionnaire based on details of each body region significant in obtaining a radiographic diagnosis. In the first part of the study the overall quality of the radiographs was evaluated. Within one region, 89.5% (43/48) chose a digital radiograph as the best image. Divided into analog and digital groups, the digital image with the highest MUSI-contrast was most often considered the best, while the analog image considered the best varied between the one with the medium and the one with the longest exposure time. In the second part of the study, each image was rated for the visibility of specific, diagnostically important details. After summarisation of the scores for each criterion, divided into analog and digital imaging, the digital images were rated considerably superior to conventional images. The results of image comparison revealed that digital radiographs showed better image detail than radiographs taken with the analog technique in all six areas of the body.

In Germany pet owners are present during X-ray examinations of dogs and cats. Due to a change in the German X-ray Ordinance and the directive "Radiation Protection in Veterinary Medicine" it is necessary to determine the body dose of the pet owners. This study in the Clinic for Small Animals includes at least ten measurements for each of thirteen X-ray examinations of a dog and four of a cat. The equivalent doses of eye lens, thyroid, chest, hands, gonads, and lower leg were measured using TLD (LiF:Mg,Cu,P). The maximum value of 52 microSv was measured on the right hand. The 99 % -quantiles amount to 13 microSv for eye lens, 9 microSv for thyroid, 2.3 microSv for chest (under lead apron), 14 microSv for both hands, 2.1 microSv for gonads (under lead apron), and 2.0 microSv for lower leg. In every case the median and mean values at the seven measuring positions are lower than 2.5 microSv per radiograph. In view of the constant measured equivalent doses under the lead apron of less than 5 microSv for the trunk and gonads per X-ray examination the measurement of the personal dose of the pet owner during every X-ray examination of small animals is not justified. Alternatively, with reference to up-to-date measurements and the presented paper a certificate of exemption from the dose determination for pet owners could be applied for from the local authority.

The implantation of a total hip prosthesis is an operation which is performed frequently due to advanced hip joint damage both in humans and in veterinary medicine in dogs. The long-term result of a hip prosthesis is mainly determined by aseptic loosening of the prosthesis; among other causes, abrasion particles of the tribological pairing are responsible for the loosening. For the analysis of the surface stresses with different tribological pairings, a finite element model was generated which was based on the CAD data of a commercial total hip prosthesis. After transmission of a physiological force in the components of the three tribological pairings ceramic/polyethylene, ceramic/ceramic and metal/polyethylene, stresses were calculated. Stresses in the ceramic/ceramic tribological pairings were conspicuously higher than in the other material pairings. In the future adapted prostheses have to be developed that ensure optimal friction and absorption characteristics of the components.

Due to the great variations among the shape of the skull in different breeds, the routine use of computed tomography in the diagnosis of central nervous diseases in the dog requires basic knowledge of the structure of the inner subarachnoidal spaces. In neoplastic as well as in inflammatory brain disease, changes of the size and shape of liquor filled spaces can be found. In the present study, the easily demonstrable lateral ventricles of the brain of ten dogs of each breed, respectively, without cerebral disease belonging to the breeds German Shepherd (DSH), Dachshund, Boxer, Labrador Retriever and Toy poodle were characterized with regard to their two-dimensional expansion. The average width and height of the lateral ventricles were ascertained for each breed. The Boxer had the relatively largest lateral ventricles, whereas in the other breeds,their sizes were very similar. 32 of the dogs investigated (64%) had symmetric lateral ventricles, and in 18 dogs (36%) they were asymmetric. Of these 18 cases, the left lateral ventricle was larger in 12 dogs (67%).

The degenerative wear and pathologic damage of the joints are reasons for total endoprotheses in man as well as in dogs. The main problem is the aseptic loosening of the protheses. By usig the finite-element-method, the total endoprothesis is designed with new features, with the purpose of preventing loosening and being better adapted to load transmission. In order to simulate the femur of the dog for the numerical analysis, a material law is developed. By taking into account the anisotropy and the local density of the cancellous bone in the femoral head, the young's modules are experimentally determined. The measurements are performed by ultrasonic methods on femoral heads of euthanised dogs. The results show planar isotropic cancellous bone.

The purpose of this study was to elaborate on the advantages and limits of computed tomography (CT) in the differentiation of thoracic lesions, in particular neoplasias. In the course of the investigation CT-scans of the thorax of 31 dogs with lesions in the area of the lungs or mediastinum were evaluated. The lesions were rated by morphology, distribution pattern, attenuation values and contrast-enhancement. Biopsies or the whole body underwent a pathohistological examination. Of the 31 dogs 17 had neoplastic and 14 had inflammatory lesions in the thoracic region. With help of the CT, the exact localisations of the different lesions was possible in most cases. Due to their characteristic morphologies, distribution patterns and attenuation values the differentiation between inflammatory and neoplastic lesions was possible in most cases (n=25/31) on the basis of the CT-scans. Mean non-enhanced CT attenuation values of the neoplastic lesions ranged between 31 and 50 HU, of the inflammatory lesions between -251 and 9 HU. Both neoplastic and inflammatory lesions showed contrast enhancement (between 14 and 38 HU and between 2 and 95 HU respectively). The mediastinal abcesses enhanced mainly on the periphery of the lesion. A differentiation of the various types of neoplastic lesions based on the non-enhanced attenuation values was not successful. Only metastasis could be differentiated because of their distribution pattern.

Since computed tomography (CT) was introduced to veterinary medicine in the beginnings of the 80s, the CT of the skull has mainly been used for the diagnosis of brain tumors. The present study includes 18 dogs and five cats, all patients of the Clinic of Small Animals of the School of Veterinary Medicine Hannover. After a CT of their skull was made, a primary intracranial neoplasm was confirmed by a pathomorphological and -histogical examination post mortem. Four of the five cats had a meningioma, one cat an astrocytoma. With five cases the meningioma also predominated in the dogs, followed by primary lymphoma with four cases. An astrocytoma, an oligodendroglioma and a choroid plexus papilloma were diagnosed respectively in two dogs. A pituitary gland tumor, a germ cell tumor and a medulloblastoma represented individual cases. Based on the pathomorphologically and -histologically confirmed diagnosis, characteristics of these primary brain neoplasms can be found in their CT image. However, changes are not pathognomonic for a certain type of tumor; a definitive diagnosis cannot be made from the CT image.

In order to establish reference values for corneal sensitivity in ophthalmologically healthy persians (n = 40) and domestic short hair cats (n = 60) a prospective study was conducted. Furthermore corneal sensitivity in 48 cats with a corneal sequestrum was measured. Corneal sensitivity was recorded with the help of the aesthesiometer according to Cochet and Bonnet in five different corneal locations (central, nasal, dorsal, temporal, and ventral). The sensitivity for the central corneal region was recorded as amounting to 3.58 +/- 0.56 cm in ophthalmologically healthy domestic short hair cats and to 2.97 +/- 0.58 cm in healthy persian cats. The sensitivity of the central corneal area of a cat with a corneal sequester only amounts to 2.03 +/- 0.53 cm. Between the diseased and the healthy eyes no statistical difference could be demonstrated for any of the measured corneal locations. The sensitivity of the peripheral corneal locations is significantly lower than that of the central corneal region in all three groups examined.

The objective of the present study was to analyze the mode of inheritance for congenital sensorineural deafness (CSD) in German Dalmatian dogs by consideration of association between phenotypic breed characteristics and CSD. Segregation analysis with regressive logistic models was employed to test for different mechanisms of genetic transmission. Data were obtained from all three Dalmatian kennel clubs associated with the German Association for Dog Breeding and Husbandry (VDH). CSD was tested by veterinary practitioners using standardized protocols for Brainstem Auditory-Evoked Response (BAER). The sample included 1899 Dalmatian dogs from 354 litters in 169 different kennels. BAER testing results were from the years 1986 to 1999. Pedigree information was available for up to seven generations. The segregation analysis showed that a mixed monogenic-polygenic model including eye color as covariate among all other tested models best explained the segregation of affected animals in the pedigrees. The recessive major gene segregated in dogs with blue and brown eye color as well as in dogs with and without pigmented coat patches. Models which took into account the occurrence of patches, percentage of puppies tested per litter, or inbreeding coefficient gave no better adjustment to the most general (saturated) model. A procedure for the simultaneous prediction of breeding values and the estimation of genotype probabilities for CSD is expected to improve breeding programs significantly.

164 total hip prostheses of different manufacturers were implanted over an 8-year period. Clinical records were evaluated with a complication rate of 29.0% (42 of 145 joints) or 31.7% (39 of 123 dogs). The complications encountered in dogs that received the modular hip prosthesis (Biomécanique, Bretigny-sur-orge, France) amounted to 16.3% (15 of 92), dogs that received a fixed head prosthesis (5 different manufactures) had 39% complications (28 of 72). Although the complication rate was influenced by different surgeons (n = 5) with different system predelictions and a different learning curve it was obvious that luxations (n = 6 of 10) and stem fractures (n = 5) more often occurred with the fixed head prosthesis systems. These stem fractures might be due to implant material failure or due to improper cementation followed by fatigue material failure. Femur fracture or infection were encountered with both prosthesis systems.