[Food hygiene and safety - What is your diagnosis?] / Lebensmittelhygiene ­ Was ist Ihre Diagnose?

INTRODUCTION: A healthy, 1,5 year old female wild boar (Sus scrofa) was shoot in a hunting district in Switzerland on June 22, 2023. The meat inspection revealed noticeable skin changes on all four distal extremities which were described histologically as multifocal epidermal hyperplasia and moderate orthokeratotic hyperkeratosis. The rest of the animal body, the organs and the lymph nodes were without any obvious lesions. The diagnosis of papilloma virus-associated exophytically growing papillomas was made. The venison was approved as fit for human consumption.

INTRODUCTION: Un sanglier femelle (Sus scrofa) en bonne santé, âgé d'un an et demi, a été abattu dans le nord de la Suisse le 22 juin 2023. L'inspection de la viande a révélé des modifications cutanées notables sur les quatre extrémités distales des membres qui ont été décrites histologiquement comme une hyperplasie épidermique multifocale et une hyperkératose orthokératosique modérée. Le reste du corps de l'animal, les organes et les ganglions lymphatiques ne présentaient aucune lésion évidente. Le diagnostic de papillomes à croissance exophytique associés à des papillomavirus a été posé. La venaison a été déclarée propre à la consommation humaine.

Clinical, laboratory and ultrasonographic findings in 94 cows with type-1 abomasal ulcer.

INTRODUCTION: This study included 94 cows aged 2.1 to 12.0 years (5.2 ± 2.05 years) that were examined at a referral clinic because of type-1 abomasal ulcer. The most common clinical findings were poor general health status (94%), partial or complete anorexia (93%), congested scleral vessels (89%), decreased skin surface temperature (76%), decreased or absent faecal output (72%), abdominal guarding (59%), tachypnoea (56%), rumen atony (53%) and positive percussion and simultaneous auscultation and/or ballottement and simultaneous auscultation on the right side (53%). The most common laboratory findings were hypokalaemia (68%), positive base excess (60%) and azotaemia (51%). The chloride concentration of rumen fluid was increased in 48% of the cows. The diagnosis of type-1 ulcer was made during laparotomy and/or postmortem examination. One or more concurrent diseases were diagnosed in 97% of the cows. Seventy-eight (83%) cows were euthanased immediately after the initial examination, during laparotomy or after unsuccessful treatment, and eight (8.5%) cows died, and all were examined postmortem. Eight (8.5%) cows were discharged and six of these made a complete recovery.

INTRODUCTION: La présente étude a inclus 94 vaches âgées de 2,1 à 12,0 ans (5,2 ± 2,05 ans) qui ont été examinées dans une clinique de référence en raison d'un ulcère de la caillette de type 1. Les signes cliniques les plus courants étaient un mauvais état de santé général (94%), une anorexie partielle ou complète (93%), des vaisseaux scléraux congestionnés (89%), une diminution de la température de la surface de la peau (76%), une diminution ou une absence de débit fécal (72%), une défense abdominale (59%), de la tachypnée (56%), une atonie du rumen (53%) et une percussion positive avec auscultation simultanée (PSA) et / ou ballottement et auscultation simultanée (BSA) du côté droit (53%). Les résultats de laboratoire les plus courants étaient l'hypokaliémie (68%), l'excès de base positif (60%) et l'azotémie (51%). La concentration en chlorure du liquide du rumen a augmenté chez 48% des vaches. Le diagnostic d'ulcère de type 1 a été posé lors de la laparotomie et/ou de l'autopsie. Une ou plusieurs maladies concomitantes ont été diagnostiquées chez 97% des vaches. Soixante-dix-huit vaches (83%) ont été euthanasiées immédiatement après l'examen initial, pendant la laparotomie ou après un traitement infructueux, et huit vaches (8,5%) sont mortes. Toutes ont été examinées post-mortem. Huit vaches (8,5%) sont sorties de clinique et six d'entre elles ont complètement récupéré.

A case series highlighting the role of different gamma-herpesviruses in Equine Multinodular Pulmonary Fibrosis.

INTRODUCTION: This case series describes three cases of equine multinodular pulmonary fibrosis (EMPF) diagnosed at the Clinic for Equine Internal Medicine at the University of Zurich between 2012 and 2017. Current information on etiology and treatment options are presented. Two horses showed mild signs of chronic lower respiratory tract disease and one horse was presented with acute signs of disease including recurrent fever spikes and tachypnea. Diagnosis was achieved by physical examination, radiographic findings, and PCR testing for equine herpesviruses (EHV) of bronchoalveolar lavage (BAL) fluid or lung tissue obtained by biopsy. All horses were euthanized due to continuing deterioration after attempted treatment. Post mortem histological examination of lung tissue showed severe multifocal diffuse to confluent fibrosis in two cases and in another horse a discrete nodular fibrosis pattern. Panherpes nested PCR revealed the presence of equine herpesvirus 5 (EHV-5) DNA in lung tissue of one horse whereas in two other horses, asinine herpes virus 5 (AHV-5) was detected. EMPF should be considered as a differential diagnosis in horses with acute and chronic respiratory disease, including horses non-responsive to treatment for equine asthma.

INTRODUCTION: Cette série de cas décrit trois cas de fibrose pulmonaire multinodulaire équine (EMPF) diagnostiqués à la Clinique de médecine interne équine de l'Université de Zurich entre 2012 et 2017. Des informations actuelles sur l'étiologie et les options de traitement sont présentées. Deux chevaux présentaient de légers signes de maladie chronique des voies respiratoires inférieures et un cheval présentait des signes aigus de maladie, notamment des pics de fièvre récurrents et une tachypnée. Le diagnostic a été obtenu grâce à un examen physique, des résultats radiographiques et des tests PCR pour les virus herpès équins (EHV) du liquide de lavage broncho-alvéolaire (BAL) ou du tissu pulmonaire obtenus par biopsie. Tous les chevaux ont été euthanasiés en raison d'une détérioration continue après une tentative de traitement. L'examen histologique post mortem du tissu pulmonaire a montré une fibrose multifocale diffuse à confluente sévère dans deux cas et chez un cheval un type de fibrose nodulaire discret. La PCR par Panherpes a révélé la présence d'ADN de virus herpès équin 5 (EHV-5) dans le tissu pulmonaire d>un cheval alors que chez deux autres chevaux, le virus de l>herpès asinien 5 (AHV-5) a été détecté. L'EMPF doit être considéré comme un diagnostic différentiel chez les chevaux souffrant d'une maladie respiratoire aiguë et chronique, y compris les chevaux ne répondant pas au traitement de l'asthme équin.

Variation in fat content between liver lobes and comparison with histopathological scores in dairy cows with fatty liver.

BACKGROUND: The assessment of a liver biopsy remains the gold standard for diagnosing and staging fatty liver in dairy cows, which is often necessary for diagnostic and research purposes. Accuracy of the diagnosis relays on the quality of the biopsy, the assumed representativeness of a small tissue sample for a disease process throughout the liver and accurate human evaluation of histologic specimens. The objective of the present study was to assess the distribution of triacylglycerol (TAG) infiltration throughout the parenchyma of livers with different degrees of fatty liver in dairy cows. In addition, histopathological scores from the corresponding specimens were compared to a quantitative measurement of TAG, as well as the agreement between two observers. METHODS: Thirty livers with different degrees of lipid infiltration were selected and 10 different locations throughout the liver were assessed. The TAG content was measured enzymatically, calculated in % or mg/g wet weight, and assigned to a scoring system. Corresponding tissue specimens were stained with hematoxylin-eosin (H&E) and Oil red O (ORO) for histopathological evaluation, using a scoring system. RESULTS: The difference in TAG content between any locations was less than 2%. Based on the scoring system the TAG concentration was even distributed in 79.3% of the livers. Based on kappa statistics the agreement between two pathologists and staining technique in scoring histological specimens was moderate to fair. CONCLUSIONS: Overall the distribution of TAG throughout the liver and the accuracy of human evaluation of liver biopsies may lead to acceptable diagnoses for clinical purposes. Within the liver lobules a common pattern of lipid distribution depending on severity could be observed. For the staging of lipid infiltration for research projects, some degree of variation needs to be considered.

[Spina bifida aperta in a sheep lamb]. / Spina bifida aperta bei einem Schaflamm.

The case report describes the symptoms and diagnostic methods of a spina bifida aperta in a new born lamb. The most relevant clinical findings were recumbency immediately after birth with normal consciousness and suckling reflexes, alterations of the skin and coat in the lumbosacral region as well as dysuria. The biochemical and haematological screening of the blood indicated no abnormalities. While the radiological examination of the spine showed no clear evidence of the cause of the clinical sings the ultrasound and computed tomography examination revealed an incomplete closure of the vertebral arch between the 4th lumbar and the 3rd sacral vertebrae. Additionally, a hernia with similar density to the spinal cord was present in the same region of the spine. Based on the findings the lamb was euthanized. The pathological examination confirmed the incomplete closure of the vertebral arch and moreover a myelomeningocele has been diagnosed. In the histopathological examination the white and grey matter were separated in the area of the macroscopic visible lesions. Due to non-specific clinical symptoms imagining diagnostics can be crucial to confirm the diagnosis of this rare syndrome.

[Ulcerative colitis and proctitis in two Swiss Braunvieh cows]. / Ulzerierende Colitis und Proktitis bei zwei Braunviehkühen.

Two Swiss Braunvieh cows were referred to our clinic because of narrowing of the rectum and difficult rectal examination attributable to restricted arm movement within the pelvic cavity. Cow 1 also had perforation of the cranial rectum and cow 2 had multiple small funnel-shaped depressions in the rectal mucosa. Both cows had ultrasonographic evidence of peritonitis with thickening of the intestinal wall and fibrin and fluid accumulation in the abdominal cavity. A diagnosis of peritonitis was made in both cows, most likely caused by rectal perforation; they were euthanized and a post-mortem examination was carried out. Both cows had proctitis and ulcerative colitis with three or four perforated ulcers which were associated with fibrinopurulent peritonitis. The final diagnosis was ulcerative colitis and proctitis of unknown aetiology. Infectious causes of colitis and proctitis, including bovine viral diarrhoea, adenovirus infection and salmonellosis, and trauma and poisoning were ruled out.

Acinar cell carcinoma of exocrine pancreas in two horses.

Two horses were presented with non-specific clinical signs of several weeks' duration and were humanely destroyed due to a poor prognosis. At necropsy examination, both horses had multiple small, white nodules replacing pancreatic tissue and involving the serosal surface of the abdominal cavity, the liver and the lung. Microscopically, neoplastic cells were organized in acini and contained abundant (case 1) or sparse (horse 2) intracytoplasmic zymogen granules. Immunohistochemically, both tumours expressed amylase and pan-cytokeratin, but not insulin or neuron-specific enolase. In case 2, a low percentage of neoplastic cells expressed glucagon and synaptophysin. The presence of zymogen granules was confirmed in both cases by electron microscopy and occasional fibrillary or glucagon granules were observed in cases 1 and 2, respectively. A diagnosis of pancreatic acinar cell carcinoma was established in both horses.

Transcriptional targeting of DCs with lentiviral vectors induces antigen-specific tolerance in a mouse model of multiple sclerosis.

The aim of this work was to induce permanent tolerance toward self-antigens involved in autoimmune diseases, such as multiple sclerosis (MS). We hypothesized that the stable auto-antigen presentation by dendritic cells (DCs) would tolerize auto-reactive T cells and, therefore, prevent disease development in a mouse model of experimental autoimmune encephalomyelitis (EAE), which closely resembles MS. Specifically, our strategy included the ex vivo modification of hematopoietic stem cells (HSCs) with self-inactivating (SIN) lentivirus vectors that transcriptionally target the expression of myelin antigens to DCs. As SIN lentivirus vectors support the genomic integration of transgene sequences in HSC, the transduced and transplanted HSC may provide a constant supply of antigen expressing steady-state DCs. Here, we demonstrate that targeting myelin oligodendrocyte glycoprotein (MOG) expression to DCs indeed resulted in complete and stable protection from EAE. No histological signs of EAE, such as demyelination, axonal damage, or infiltration of leukocytes in brain, spinal cord and optical nerve, were observed in tolerized mice. Tolerance induction was concomitant with the efficient deletion of MOG-specific T cells and the generation of Foxp3(+) regulatory T cells and, most importantly, directed toward a specific self-antigen while T-cell reactivity to unrelated foreign antigens was fully preserved.

[First cases of besnoitiosis in cattle in Switzerland]. / Erste Fälle von Besnoitiose bei Rindern in der Schweiz.

Bovine besnoitiosis has been diagnosed in neighboring countries but not in Switzerland so far. This disease occurs endemically in France and focal outbreaks have been reported in Germany and Italy. To determine if Besnoitia besnoiti is introduced into Switzerland through the import of breeding cattle from France, a systematic serological survey was performed. A total of 412 breeding cattle (from 114 farms) imported from France into Switzerland between 2005 and 2011, were serologically examined for antibodies against B. besnoiti using a commercial ELISA kit (PrioCHECK© Besnoitia Ab 2.0, Prionics AG, Zurich, Switzerland). Sixty-four (15.5 %) animals reacted positive in ELISA. The serologic diagnosis was confirmed by an indirect immunfluorescence test (IFAT) and a Western blot (WB) in only 2 Limousin cows imported from France on a farm in Eastern Switzerland. Subsequently, this whole herd (n = 16) was examined clinically and serologically and 2 additional Limousin cows imported from Germany also reacted positive in the three serological tests. One of these cows presented B. besnoiti tissue cysts in the scleral conjunctiva and typical skin lesions in the head region. The infection was further confirmed cytologically, histopathologically and by PCR. It can be concluded that the parasite is most likely being introduced into Switzerland through the import of infected animals.

[Squamous cell carcinoma of the reticulum and liver in a Simmental cow]. / Plattenepithelkarzinom in Haube und Leber bei einer Fleckviehkuh.

This report describes an 8.8-year-old Simmental cow with squamous cell carcinoma of the reticulum and liver. The cow had calved recently and was referred to our clinic because of intractable fever, anorexia and progressive indigestion. The general condition and mental status were moderately affected and rectal temperature and respiratory rate were significantly elevated. There were no ruminal sounds and pinching of the withers consistently elicited a grunt. Serum activities of gamma glutamyl transferase, glutamate dehydrogenase and sorbitol dehydrogenase were elevated. Radiographic examination of the reticulum and ultrasonographic examination of the reticulum, liver and abdominal cavity revealed multifocal, poorly demarcated, heterogeneous and echogenic changes in the liver. Biopsy of these lesions yielded a diagnosis of squamous cell carcinoma. The cow was euthanized and a postmortem examination confirmed the diagnosis. A 15 by 15 cm neoplasm was found in the reticular wall, and histological examination showed squamous cell carcinoma. It was assumed that the reticular mass was the primary tumour, which metastasized to the liver via the portal vein.

[Effect of vaccination against GnRH (Bopriva®) in the male pubertal calf]. / Wirkung einer Impfung gegen GnRH (Bopriva®) beim männlichen pubertären Kalb.

The objective of this experiment was to investigate the effectiveness of a newly developed bovine anti-GnRH vaccine (Bopriva®, Pfizer Animal Health, Australia). A total of 12 peripubertal bull calves aged between 6 and 8 months were used, 2 randomly selected animals served as controls. Animals were vaccinated twice at an interval of 4 weeks with 1ml of Bopriva® (400 µg GnRH-protein-conjugate) subcutaneously in the neck and observed for a total of 36 weeks. Scrotal circumference was measured every week and blood samples were also taken weekly for the determination of testosterone and GnRH antibodies. Three months after the second injection (booster), 5 animals were slaughtered and their testes histologically examined. GnRH antibody titers rapidly began to rise after the second vaccination and reached peak values 3 weeks later. Testosterone concentrations decreased to values below 0.5 ng/ml serum 1 week after the booster and remained at this low level for at least 10 weeks. The following increase of testosterone occurred individually within 11 and 23 weeks after the booster injection. Histological examination of testes in vaccinated animals showed an incomplete spermatogenesis with impaired or no production of spermatids and a reduced diameter of seminiferous tubules. From our results we conclude that in the peripubertal bull two injections with the new bovine anti-GnRH vaccine 4 weeks apart is effective in suppressing testicular growth and testosterone secretion during at least 10 weeks after the booster injection.

Chondrosarcoma in the humerus of a goat.

The clinical, radiographical and histo-pathological findings of a chondrosarcoma in the humerus of a goat are discussed. An 11-year-old female Saanen goat was admitted for evaluation of chronic, progressive left forelimb lameness. Clinical examination revealed signs of pain in the shoulder region. Radiographs of the scapulohumeral joint showed a large lytic lesion of the proximal third of the humerus with cortical destruction, intralesional calcification and marked periosteal reactions. Differential diagnoses included aggressive bone lesions as seen with osteomyelitis or a primary bone tumour, such as osteosarcoma, chondrosarcoma or fibrosarcoma. The goat was euthanatized for humane reasons because of the poor prognosis. On the basis of the histopathological findings, the lesion was diagnosed as grade II chondrosarcoma. The tumour had already spread to the lungs and the left prescapular lymph node at the time of diagnosis.

[Ultrasonographic findings and treatment in a cow with a haemangiosarcoma of the urinary bladder]. / Ultraschallbefunde und Therapie bei einer Kuh mit einem Hämangiosarkom in der Harnblase.

A 4.5-year-old Swiss Braunvieh cow was presented to the Department of Farm Animals, University of Zurich, because of severe haematuria. All other clinical findings were within normal ranges. Transrectal ultrasonography revealed a 1 cm x 1 cm echogenic, irregularly-shaped, raised mass in the wall of the urinary bladder. Endoscopy identified the mass as a proliferation, approximately 0.5 cm in diameter, which was bleeding continuously. Thermocautery of the bleeding site was carried out twice five days apart via endoscopy. Clinical signs resolved for the remainder of the cow's life; she was slaughtered 15 months later because of infertility. Histological examination of the mass revealed a haemangiosarcoma.

Immunohistochemical diagnosis of persistent infection with Bovine Viral Diarrhea Virus (BVDV) on skin biopsies.

Detection of persistent infection with BovineViral Diarrhea Virus (BVDV) is essential for both epidemiological and clinical reasons. In addition to the classical virological methods such as virus isolation in tissue culture, ELISA and RT-PCR, immunohistochemistry of skin biopsies has become a useful and reliable tool. Assuming that the presence of BVDV antigen in skin structures is restricted to persistent infection, this method could differentiate from transient infection. In order to answer this question, 6 calves were experimentally infected orally with a non-cytopathic genotype 1 BVDV strain belonging to the subtype k.The calves developed fever, mucopurulent nasal discharge, coughing and leucopenia with relative lymphopenia. Immunohistochemistry of skin biopsies taken daily up to day 13-post infection did not reveal any evidence of BVDV infection. BVDV was, however, isolated from blood samples on cell cultures. Anti-NS3-antibody-ELISA and serum neutralization tests showed that all six calves seroconverted. We conclude that in acute BVDV infections, with genotype 1 and the subtypes found in Switzerland (b, e, h and k) viral antigen is not found in epidermal structures of the skin. In contrast, persistently infected animals test positive for BVD viral antigen by immunohistochemistry of the skin.

Pituitary macroadenoma in a cat with diabetes mellitus, hypercortisolism and neurological signs.

A 13-year-old neutered male European short-hair cat was presented because of blindness and behavioural abnormalities. On physical examination, abnormal behaviour, compulsive walking, circling, continuous vocalization and blindness were the main neurological signs. In addition, abdominal alopecia, thin and inelastic skin, weight loss despite polyphagia, polyuria and polydipsia were present. Laboratory investigation revealed diabetes mellitus and pituitary-dependent hypercortisolism. Diagnostic imaging showed bilaterally enlarged adrenals and a large pituitary mass. Histopathological and immunohistochemical examination confirmed the clinical diagnosis of an ACTH-producing pituitary macroadenoma.

BMP-silk composite matrices heal critically sized femoral defects.

Clinical drawbacks of bone grafting prompt the search for alternative bone augmentation technologies such as use of growth and differentiation factors, gene therapy, and cell therapy. Osteopromotive matrices are frequently employed for the local delivery and controlled release of these augmentation agents. Some matrices also provide an osteoconductive scaffold to support new bone growth. In this study, silkworm-derived silk fibroin was evaluated as an osteoconductive matrix for healing critical sized mid-femoral segmental defects in nude rats. Four treatment groups were assessed over eight weeks: silk scaffolds (SS) with recombinant human BMP-2 (rhBMP-2) and human mesenchymal stem cells (HMSC) that had been pre-differentiated along an osteoblastic lineage ex vivo (Group I; pdHMSC/rhBMP-2/SS); SS with rhBMP-2 and undifferentiated HMSCs (Group II; udHMSC/rhBMP-2/SS); SS and rhBMP-2 alone (Group III; rhBMP-2/SS); and empty defects (Group IV). Bi-weekly radiographs revealed a progressive and similar increase in Group I-III mean defect mineralization through post-operative week (POW) 8. Radiographs, dual energy x-ray absorptiometry, and micro-computed tomography confirmed that Groups I-III exhibited similar substantial and significantly (p<0.05) greater defect mineralization at POW 8 than the unfilled Group IV defects which remained void of bone. No significant differences in Groups I-III defect healing at POW 8 were apparent using these same assays or mechanical testing. Histology at POW 8 revealed moderately good bridging of the parent diaphyseal cortices with woven and lamellar bone bridging islands of silk matrix in Groups I and III. Group II defects possessed comparatively less new bone which was most abundant adjacent to the parent bone margins. Elsewhere the silk matrix was more often enveloped by poorly differentiated loose fibrous connective tissue. Group IV defects showed minimal new bone formation. None of the treatment groups attained the mean mineralization or the mean biomechanical strength of identical defects implanted with SS and pdHMSCs alone in a previous study. However, addition of rhBMP-2 to SS prompted more bone than was previously generated using udHMSC/SS or SS alone. These data imply the clinical potential of silk scaffolds and rhBMP-2 as composite osteopromotive implants when used alone or with select stem cell populations. Additional studies in larger species are now warranted.

HSV-1 amplicon-mediated post-transcriptional inhibition of Rad51 sensitizes human glioma cells to ionizing radiation.

Standard treatment for glioblastoma multiforme and other brain tumors consists of surgical resection followed by combined radio-/chemotherapy. However, radiation resistance of tumor cells limits the success of this treatment, and the tumors invariably recur. Therefore, the selective inhibition of molecular mediators of radiation resistance may provide therapeutic benefit to the patient. One of these targets is the Rad51 protein, which is a key component of the homologous recombinational repair of DNA double-strand breaks. Here, we investigated whether post-transcriptional silencing of Rad51 by herpes simplex virus-type 1 (HSV-1) amplicon vector-mediated short interfering RNA expression can enhance the antitumor effect of radiation therapy. We demonstrate that these vectors specifically and efficiently inhibited the radiation-induced recruitment of Rad51 into nuclear foci in human glioma cells. The combination of vector-mediated silencing of Rad51 expression and treatment with ionizing radiation resulted in a pronounced reduction of the survival of human glioma cells in culture. In athymyc mice, a single intratumoral injection of Rad51-specific HSV-1 amplicon vector followed by a single radiation treatment resulted in a significant decrease in tumor size. In control animals, including mice that received an intratumoral injection of Rad51-specific amplicon vector but no radiation treatment, the tumor sizes increased.

Silk based biomaterials to heal critical sized femur defects.

Bone auto- and allografts have inherent drawbacks, therefore the treatment of non-unions and critical size defects in load bearing long bones would benefit from the use of osteopromotive biodegradable, biocompatible and mechanically durable matrices to enhance migration or delivery of cell populations and/or morphogens/cytokines. Silk fibroin biomaterial scaffolds were evaluated as osteopromotive matrices in critical sized mid-femoral segmental defects in nude rats. Four treatment groups were assessed over 8 weeks in vivo: silk scaffolds (SS) with human mesenchymal stem cells (hMSCs) that had previously been differentiated along an osteoblastic lineage in vitro (group I; pdHMSC/SS); SS with undifferentiated hMSCs (group II; udHMSC/SS); SS alone (group III; SS); and empty defects (group IV). When hMSCs were cultured in vitro in osteogenic medium for 5 weeks, bone formation was characterized with bimodal peak activities for alkaline phosphatase at 2 and 4 weeks. Calcium deposition started after 1 week and progressively increased to peak at 4 weeks, reaching cumulative levels of deposited calcium at 16 mug per mg scaffold wet weight. In vivo osteogenesis was characterized by almost bridged defects with newly formed bone after 8 weeks in group I. Significantly (P < 0.01) greater bone volumes were observed with the pdHMSC/SS (group I) implants than with groups II, III or IV. These three groups failed to induce substantial new bone formation and resulted in the ingrowth of cells with fibroblast-like morphology into the defect zone. The implantation of pdHMSC/SS resulted in significantly (P < 0.05) greater maximal load and torque when compared to the other treatment regimens. The pdHMSC/SS implants demonstrated osteogenic ability in vitro and capacity to thrive towards the healing of critical size femoral segmental defects in vivo. Thus, these new constructs provide an alternative protein-based biomaterial for load bearing applications.

Malignant histiocytosis of the brain in three dogs.

Three dogs (two Rottweilers and a Flat-coated retriever) showed various neurological signs, including apathy, depression, circling, a partial decrease in functions associated with cranial nerves, seizures, hyperaesthesia, proprioceptive deficits, and increased spinal reflexes. In all three cases, necropsy revealed a solid, distinct, white mass in the brain and multiple, poorly demarcated, firm nodular proliferations in the lung; in one case the liver was also affected. Histopathological examination showed loosely aggregated, pleomorphic cells, with abundant eosinophilic cytoplasm. The neoplastic cells sometimes contained vacuoles or phagocytized cells. Binucleated and multinucleated giant cells, and mitotic figures, were common. Immunohistochemically, the tumour cells reacted strongly for lysozyme and vimentin, but there was no reaction for S-100 protein, cytokeratin, CD3 or CD79a. The histological and immunohistochemical examinations indicated a histiocytic origin of the tumour cells and malignant histiocytosis was therefore diagnosed.

Histomorphological and immunohistochemical findings in testes, bulbourethral glands and brain of immunologically castrated male piglets.

The aim of this study was the histological and immunohistochemical evaluation and comparison of testicular, bulbourethral and brain tissue in immunized and intact control boars. Fourteen male piglets, aged between 10 and 16 weeks, were vaccinated twice subcutaneously 4 to 5 weeks apart with Improvac, an anti-GnRH vaccine. The pigs were sacrificed 1 to 16 weeks following the second injection. Testicular weight was recorded and various tissue samples were collected and fixed in formalin and Bouin's fixative for histological examination. In addition, 2 boars were immunized five times and slaughtered 60 weeks after the last injection. Histological and immunohistological studies performed on testes and epididymes showed clear signs of atrophy in the immunized animals and a significant reduction in paired testes weight was seen in treated boars. Microscopically, the mean diameter of the seminiferous tubules was markedly reduced. Spermatogonia as well as few spermatocytes were visible between the Sertoli cells and Leydig cells were atrophic. None or only few spermatozoa were detected in the epididymis. The bulbourethral glands of immunocastrated pigs were smaller than in control pigs and showed histological evidence of atrophy. Immunohistological detection of LH and FSH in the pituitary gland of treated and control boars showed no quantifiable difference in the amount of these two gonadotropins and no lesions were visible in the hypothalamus and the pituitary gland. From our findings it can be concluded that the anti-GnRH vaccine Improvac induces severe atrophy of testes and bulbourethral glands in immunized pigs. This effect appears to be reversible, depending on the immune response of each animal and the time elapsed after the last booster injection.