Biomechanical comparison of titanium alloy additively manufactured and conventionally manufactured plate-screw constructs.

AIM: To biomechanically compare the bending stiffness, strength, and cyclic fatigue of titanium additively manufactured (AM) and conventionally manufactured (CM) limited contact plates (LCP) of equivalent dimensions using plate-screw constructs. METHODS: Twenty-four 1.5/2.0-mm plate constructs (CM: n = 12; AM: n = 12) were placed under 4-point bending conditions. Data were collected during quasi-static single cycle to failure and cyclic fatigue testing until implants plastically deformed or failed. Bending stiffness, bending structural stiffness, and bending strength were determined from load-displacement curves. Fatigue life was determined as number of cycles to failure. Median test variables for each method were compared using the Wilcoxon rank sum test within each group. Fatigue data was also analysed by the Kaplan-Meier estimator of survival function. RESULTS: There was no evidence for a difference in bending stiffness and bending structural stiffness between AM and CM constructs. However, AM constructs exhibited greater bending strength (median 3.07 (min 3.0, max 3.4) Nm) under quasi-static 4-point bending than the CM constructs (median 2.57 (min 2.5, max 2.6) Nm, p = 0.006). Number of cycles to failure under dynamic 4-point bending was higher for the CM constructs (median 164,272 (min 73,557, max 250,000) cycles) than the AM constructs (median 18,704 (min 14,427, max 33,228) cycles; p = 0.02). Survival analysis showed that 50% of AM plates failed by 18,842 cycles, while 50% CM plates failed by 78,543 cycles. CONCLUSION AND CLINICAL RELEVANCE: Additively manufactured titanium implants, printed to replicate a conventional titanium orthopaedic plate, were more prone to failure in a shorter fatigue period despite being stronger in single cycle to failure. Patient-specific implants made using this process may be brittle and therefore not comparable to CM orthopaedic implants. Careful selection of their use on a case/patient-specific basis is recommended.

Disseminated Rasamsonia argillacea infection in a dog.

CASE HISTORY: A 4-year-old, male neutered Borzoi presented for unlocalised pain and frequent episodes of vocalisation. CLINICAL FINDINGS: Pain was localised to the lumbar spine and radiographs revealed a L3-L4 lesion consistent with discospondylitis. The dog was treated for presumptive bacterial discospondylitis with surgical debridement, spinal stabilisation, and cephalexin. Samples collected from the affected intervertebral disc at the time of surgery revealed lymphoplasmacytic inflammation with no causative agent identified on histopathology or bacterial culture. After an initial period of improvement, signs recurred despite an 8-week antibiotic course, with the development of inappetence, weight loss, polydipsia, and polyuria. Repeat radiographs revealed a new cervical intervertebral lesion, and concurrent pyelonephritis was diagnosed based on blood and urine results. Fungal culture of urine resulted in growth of Rasamsonia argillacea species complex and disseminated fungal disease was clinically diagnosed. Antifungal treatment was commenced, however the dog deteriorated, and euthanasia was performed. PATHOLOGICAL FINDINGS: Multifocal white plaques were grossly visualised in the spleen, mesenteric lymph nodes, cervical vertebrae, and kidneys. Periodic acid-Schiff-positive, fine, parallel-walled, occasionally branching, septate hyphae 5-10 µm in diameter, and conidia 5-7 µm in diameter were found on sectioning all organs. R. argillacea species complex was identified by fungal culture of urine and was considered the species of fungal organism seen histologically. The isolate was subsequently confirmed as R. argillacea by DNA sequencing. DIAGNOSIS: Disseminated Rasamsonia argillacea infection. CLINICAL RELEVANCE: Rasamsonia argillacea species complex is a recognised invasive mycosis in veterinary medicine, with disseminated disease causing significant clinical complications and death. This is believed to be the first report of infection caused by R. argillacea in a dog in Australasia and highlights the importance of awareness of a potential fungal aetiology in dogs with discospondylitis.Abbreviations: CLSI: Clinical and Laboratory Standards Institute; CRI: Constant rate infusion; MEC: Minimum effective concentration; MIC: Minimum inhibitory concentration; PAS: Periodic acid-Schiff.

The effect of pearl spacing on single-cycle load-to-failure and cyclic loading parameters of 2.0†mm pearl locking plates.

AIMS: To compare the mechanical performance and mode of failure in four-point bending of two different 2.0 mm "string of pearls" locking plates that differ in dimensions. METHODS: Ten *2.0 mm, 82 mm long, 10-hole (Plate A) and ten 2.0 mm, 69 mm long, 12-hole (Plate B) Cortical Pearl Systems were secured to plate extenders and centred beneath an Instron tensile tester in four-point bending. In all constructs, a simulated fracture gap was maintained at 33 mm. Due to differences in plate dimensions, 33 mm corresponded to four pearls (Plate A) and six pearls (Plate B). Following an initial preload of 10 N, ramped single-cycle load-to-failure at 0.1 mm/second was performed in five Plate A and five Plate B constructs. Load and displacement were recorded. Constant frequency sinusoidal cyclic loading (33 N) at 20 mm/minute was performed on five Plate A and five Plate B constructs following 10 N of preload. Maximum moment and cycle count were recorded. Testing and data analysis were completed in accordance with the American Society for Testing and Materials F382-14 guidelines. Differences in performance and mode of failure were compared. RESULTS: : Plate A constructs produced higher mean values for bending stiffness (19.8 (SD 2.0) N/mm vs. 10.1 (SD 0.6) N/mm; p < 0.001), bending structural stiffness (0.77 (SD 0.08) Nm2 vs. 0.39 (SD 0.02) Nm2; p < 0.001), yield point (64.1 (SD 4.2) N vs. 54.6 (SD 3.9) N; p = 0.01), proof load (65.4 (SD 3.2) N vs. 55.6 (SD 4.0) N; p = 0.005), and bending strength (1.3 (SD 0.1) Nm vs. 1.1 (SD 0.08) Nm; p = 0.005) when compared to Plate B constructs in single cycle load-to-failure. Plate A constructs had a greater (p = 0.001) mean cycle count to failure (26,178 (SD 4,061) cycles) when compared with Plate B constructs (15,550 (SD 1,291) cycles). All plates failed by non-catastrophic plastic deformation. CONCLUSIONS: Plate A, which is wider, thicker and has a greater spacing between pearls, was mechanically superior to Plate B in four-point bending under single-cycle load-to-failure and sinusoidal cyclic loading. CLINICAL RELEVANCE: Although mechanical differences were identified in four-point bending, in vivo biomechanical performance remains undetermined. By selecting Plate B, the clinician may gain bone purchase through a greater number of pearls and thus screws per unit length, however, the inferior mechanical characteristics, as evaluated in four-point bending, should also be considered. Further research into the mechanical and biomechanical performance of these plating systems is warranted.

Animal medical genetics: a historical perspective on more than 50 years of research into genetic disorders of animals at Massey University.

Over the last 50 years, there have been major advances in knowledge and technology regarding genetic diseases, and the subsequent ability to control them in a cost-effective manner. This review traces these advances through research into genetic diseases of animals at Massey University (Palmerston North, NZ), and briefly discusses the disorders investigated during that time, with additional detail for disorders of major importance such as bovine α-mannosidosis, ovine ceroid-lipofuscinosis, canine mucopolysaccharidosis IIIA and feline hyperchylomicronaemia. The overall research has made a significant contribution to veterinary medicine, has provided new biological knowledge and advanced our understanding of similar disorders in human patients, including testing various specific therapies prior to human clinical trials.

A veterinary perspective on preventing injuries and other problems that shorten the life of working dogs.

Domesticated dogs are widely used for farm work, law enforcement, military service and in assistance roles. Farm dogs assist farmers by guarding or moving stock, reducing the requirement for human workers and enabling steep terrain to be productive. Working and service dogs are subject to illness and injury, depending on their breed characteristics, activities and the environment in which they work. There are limited data in the veterinary literature on the causes of loss and early retirement of working dogs, and targeted research is required to better determine factors that affect their incidence. Many breeds of working dog suffer from inherited forms of musculoskeletal disease; most importantly, elbow and hip dysplasia. The effectiveness of traditional radiographic (phenotypic) scoring schemes at reducing the prevalence of hip and elbow dysplasia has been variable. The selection of breeding stock should preferably be based on estimated breeding values, rather than on an individual phenotypic score/grade. Nutrition can affect physical and mental performance, disease risk and susceptibility, and recovery from injury, age-associated decline and longevity. The dietary proportions of fat, protein and carbohydrate influence fuel selection during exercise. A common concern among farmers is the difficulty of maintaining body condition in their dogs during periods of heavy work with current feeding practices. Additionally, maintaining a positive calcium balance is necessary for adaptive remodelling in response to exercise. Research strategies should include improved treatment options, the development of more specific means of genetic selection for inherited diseases, investigation into specific nutritional requirements and the dissemination of this knowledge.

Les chiens domestiqués sont très largement utilisés pour travailler dans les fermes, ainsi qu'en tant que chiens policiers, chiens militaires ou chiens d'assistance. Les chiens de ferme aident les éleveurs à garder ou à déplacer leurs troupeaux, ce qui réduit les besoins en main d'oeuvre et permet d'exploiter des terrains escarpés. Les chiens de travail et aidants sont plus ou moins exposés à la maladie et aux blessures, en fonction des caractéristiques de leur race, des tâches qui leur sont confiées et de l'environnement dans lequel ils travaillent. Il n'existe pas beaucoup d'études vétérinaires publiées sur les causes des morts et des mises à la retraite prématurées des chiens de travail, thème qu'il conviendrait d'explorer plus précisément afin de mieux déterminer les facteurs affectant l'incidence de ces problèmes. Plusieurs races canines sont atteintes de troubles musculo-squelettiques héréditaires, dont le plus important est la dysplasie du coude et de la hanche. Les méthodes traditionnelles d'interprétation radiologique (mesure des phénotypes) ont contribué à réduire la prévalence de la dysplasie du coude et de la hanche, avec des résultats variables. La sélection des reproducteurs devrait reposer sur l'estimation de leur potentiel génétique (valeur d'élevage) plutôt que sur le score ou l'échelle de mesure du phénotype d'un individu. L'alimentation joue un rôle sur les performances physiques et mentales, la sensibilité aux maladies et le risque sanitaire, les capacités de rétablissement après une blessure, le processus de vieillissement et la longévité. La proportion relative des lipides, protéines et glucides dans l'alimentation donnée aux chiens détermine les sources d'énergie utilisées durant l'effort. Une préoccupation courante parmi les éleveurs concerne la difficulté de maintenir leurs chiens en bonne condition physique pendant les périodes où le travail est le plus dur, compte tenu des pratiques d'alimentation actuelles. Il est également important de maintenir un bon équilibre en calcium afin de soutenir les capacités d'adaptation à l'effort et de récupération. Les stratégies de recherche devraient explorer les pistes d'amélioration des traitements, mettre au point des méthodes de sélection génétique axées spécifiquement sur les maladies héréditaires et mieux élucider les besoins nutritionnels des chiens, sans oublier de diffuser par la suite les connaissances ainsi obtenues.

El uso del perro doméstico en tareas agrícolas, policiales, militares y de socorro o ayuda está muy extendido. Los perros pastores ayudan al granjero vigilando o conduciendo el ganado, lo que reduce la necesidad de personal humano y permite aprovechar las tierras situadas en terrenos escarpados. Los perros de trabajo y de servicio están sujetos a enfermedades y lesiones que dependen de las características de la raza, la actividad de que se trate y el medio en que esta discurra. En la bibliografía veterinaria hay escasa información sobre las causas que subyacen a la pérdida o la jubilación anticipada de perros de trabajo. De ahí la necesidad de investigar específicamente este aspecto para determinar con más precisión los factores que influyen en ello. Muchas razas de perros de trabajo padecen formas hereditarias de enfermedad musculoesquelética, la más importante de ellas la displasia de codo o cadera. Los tradicionales sistemas de puntuación radiológica (fenotípica) han resultado de eficacia variable para reducir la prevalencia de estas dos displasias. La selección de ejemplares reproductores debería basarse no tanto en la puntuación o grado fenotípico de cada individuo como en los valores estimados de cría. La alimentación puede influir en el rendimiento físico y mental, el riesgo de enfermedades y la sensibilidad a ellas, la recuperación tras una lesión y la longevidad o la decadencia ligada a la edad. Las proporciones de grasas, proteínas y carbohidratos presentes en el régimen alimentario influyen en la selección de combustible metabólico durante la actividad física. Uno de los aspectos que preocupa a todos los granjeros es la dificultad de mantener el cuerpo del perro en condiciones en los periodos de mucho trabajo con las actuales prácticas de alimentación. Además, también es necesario mantener un saldo positivo de calcio para que tenga lugar la remodelación adaptativa del cuerpo en respuesta al ejercicio físico. Los planes de investigación deben incluir aspectos como la búsqueda de mejores alternativas de tratamiento, la obtención de medios más específicos de selección genética respecto de las enfermedades hereditarias, el estudio de necesidades nutricionales específicas y la difusión de cuanto conocimiento resulte de estas investigaciones.

Mechanical testing of a steel-reinforced epoxy resin bar and clamp for external skeletal fixation of long-bone fractures in cats.

AIMS: To provide veterinarians with confidence when using a commercially available epoxy resin in external skeletal fixators (ESF), testing was conducted to determine exothermia during curing of the epoxy resin compared to polymethylmethacrylate (PMMA), the hardness of the epoxy resin as a bar over 16 weeks, and the strength of the epoxy resin bar compared with metal clamps in similarly constructed Type 1a ESF constructs simulating the repair of feline long bone fractures. METHODS: Exothermia of the epoxy resin during curing was tested against PMMA with surface temperatures recorded over the first 15 minutes of curing, using four samples of each product. The hardness of 90 identical epoxy resin bars was tested by subjecting them to cyclic loads (1,000 cycles of 20.5 N, every 7 days) over a 16-week period and impact testing 10 bars every 2 weeks. Ten bars that were not subjected to cyclic loads were impact tested at 0 weeks and another 10 at 16 weeks. Strength of the epoxy resin product, as a bar and clamp composite, was tested against metal SK and Kirschner-Ehmer (KE) clamps and bars in Type 1a, tied-in intramedullary pin, ESF constructs with either 90° or 75° pin placement, subjected to compressive and bending loads to 75 N. RESULTS: The maximum temperature during curing of the epoxy resin (min 39.8, max 43.0)°C was less than the PMMA (min 85.2, max 98.5)°C (p<0.001). There was no change in hardness of the epoxy resin bars over the 16 weeks of cyclic loading (p=0.58). There were no differences between the median strength of the epoxy resin, SK or KE ESF constructs in compression or bending when tested to 75 N (p>0.05). Stiffness of constructs with 75° pin placement was greater for SK than epoxy resin constructs in compression (p=0.046), and was greater for KE than epoxy resin constructs in bending (p=0.033). CONCLUSIONS: The epoxy resin tested was found to be less exothermic than PMMA; bars made from the epoxy resin showed durability over an expected fracture healing timeframe and had mechanical strength characteristics comparable to metal bar and clamp ESF constructs. CLINICAL RELEVANCE: The epoxy resin ESF construct tested in this study can be considered a suitable replacement for SK or KE ESF constructs in the treatment of feline long-bone fractures, in terms of mechanical strength.

Provisional heritability estimates of four distraction index traits in a breeding population of German Shepherd dogs.

AIM To obtain provisional estimates of the heritability (h2 ) of passive laxity of the coxofemoral joints of a breeding colony of German Shepherd dogs, measured using the PennHIP distraction index (DI). METHODS Records were obtained of the PennHIP DI of right and left hips of 195 German Shepherd dogs (377 DI records) from the dog breeding colony of the New Zealand Police Dog Breeding Centre between 2003 and 2016, as well as pedigree records of 884 animals over four generations. Estimates of h2 and variance components for the log transformed DI data were obtained using restricted maximum likelihood procedures with a single trait sire model. Four DI traits for each dog were analysed: left hip, right hip, mean and worse-hip DI. The model included the fixed effects of sex and year of birth, with the age at scoring as a covariable, the random sire effect and residual error for each observation. RESULTS The h2 of the DI of the left hip (0.81, SE 0.40) was higher than the h2 of the DI of the right hip (0.35, SE 0.36). The h2 for the worse-hip DI (0.15, SE 0.28) in each dog was lower than the h2 of the individual hip DI, or the h2 for the mean of the two hips (0.53, SE 0.36) in each dog. The low number of generations prevented a meaningful analysis of the genetic trend. CONCLUSIONS AND CLINICAL RELEVANCE The h2 estimates for the left, right and mean DI traits were moderate to high, whereas the h2 estimates for the worse-hip DI (as used by the PennHIP programme for ranking of dogs) was low, but all estimates had large SE due to the small sample size. This provisional estimate of the h2 of four distraction index traits suggests that the mean DI could be useful as a selection tool against canine hip dysplasia in German Shepherd dogs, whereas the worse-hip DI may be less effective. Heritability estimates from a population with a greater number of DI measures is needed to validate this finding given the large SE in our study.

Heritabilities and genetic trends for elbow score as recorded by the New Zealand Veterinary Association Elbow Dysplasia Scheme (1992-2013) in four breeds of dog.

AIM: To estimate the heritability of the New Zealand Veterinary Association (NZVA) elbow phenotype, obtain estimated breeding values (EBV) for the worst-elbow score and estimate the genetic trends for this trait in four populous breeds of dogs, using the records from the NZVA Canine Elbow Dysplasia Scheme database (1992-2013). METHODS: Overall, 4,070 elbow records from a pedigree of 11,311 dogs were available for animals scored between 1992 and 2013. The worst elbow score between the left and right elbows was identified for each dog and used for EBV analysis. Estimates of heritability and EBV for the elbow score of dogs from German Shepherd dog, Labrador Retriever, Golden Retriever and Rottweiler breeds were obtained using restricted maximum likelihood procedures with a within-breed linear animal model. The model included the fixed effects of sex and birth year, with age at scoring as a covariable, and the random effect of animal. Genetic trends for the worst-elbow score were calculated as the regression coefficient of the EBV, weighted by reliabilities, on year of birth. RESULTS: The estimates of heritability for worst-elbow score were 0.25 (SE 0.06) in German Shepherd dogs, 0.46 (SE 0.06) in Labrador Retrievers, 0.18 (SE 0.07) in Golden Retrievers and 0.29 (SE 0.11) in Rottweilers. The genetic trend for German Shepherd dogs was -0.0082 (SE 0.0015), for Labrador Retrievers was -0.0016 (SE 0.0016), for Golden Retrievers was -0.0033 (SE 0.0010) and for Rottweilers was -0.0070 (SE 0.0023) units per annum, which were different from zero (p<0.01) in all breeds except Labrador Retrievers. CONCLUSIONS AND CLINICAL RELEVANCE: A small but favourable response to selection was achieved by three of the four breeds in the study period; during which selection for elbow traits has been largely voluntary. While the magnitude of genetic change in terms of elbow units per annum may appear small, it must be remembered that elbow scoring grades only range from 0-3. Greater improvement may be possible if compulsory screening was a requirement for pedigree breeding stock, and if greater selection pressure were applied on the basis on an individual's EBV, rather than the worst-elbow score alone. The maintenance of an open registry, with transparency of EBV information made available to all breeders, may enhance selection intensity opportunities and potentially assist with the process and progress of breeding selection.

Computer-assisted surgical correction of an antebrachial deformity in a dog.

OBJECTIVE: To report the use of three dimensional (3D) computed tomographic (CT) imaging, computer simulation and rapid prototype modelling to aid surgical correction of a complex antebrachial deformity in a dog. METHODS: A six-year-old, 13 kg spayed female Chihuahua crossbreed dog was presented for worsening forelimb gait and exercise intolerance. Both forelimbs had gross angular limb deformity with carpal hyper-flexion, valgus and radial procurvatum. Surgical planning from radiographs was problematic therefore CT data were used to generate 3D reconstructions of the antebrachium. Using imaging software we then quantified the nature of the deformity using a previously unreported method based on the centre of rotation of angulation as a 3D model. Computer simulated closing of the virtual wedge osteotomy was then performed as proof of concept. A stereolithographic model complete with osteotomy axes, was then created in plastic using a rapid prototyping machine. Oscillating saw guides were fabricated in polymethylmethacrylate and cold sterilised. A closing wedge osteotomy with de-rotation was performed and stabilised with a pre-contoured dynamic compression plate. At the three- and six-month follow-up examinations there was improved weight-bearing and cosmetic appearance. CONCLUSIONS: Computer assistance was valuable for locating and quantifying this antebrachial deformity and conceptualising the corrective surgery. The results of our study suggest that rapid prototyping can be used to create models and saw guides to simplify one-stage corrective osteotomies and more accurately treat angular limb deformity.

Kinetics of Plasma Cell-Free DNA and Creatine Kinase in a Canine Model of Tissue Injury.

BACKGROUND: Cell-free DNA (cfDNA) comprises short, double-stranded circulating DNA sequences released from damaged cells. In people, cfDNA concentrations correlate well with disease severity and tissue damage. No reports are available regarding cfDNA kinetics in dogs. OBJECTIVES/HYPOTHESIS: Cell-free DNA will have a short biological half-life and would be able to stratify mild, moderate, and severe tissue injury. Our study aims were to determine the kinetics and biological half-life of cfDNA and to contrast them with those of creatine kinase (CK). ANIMALS: Three groups of 10 dogs undergoing open ovariohysterectomy, surgery for cranial cruciate ligament rupture (CCLR), or hemilaminectomy. METHODS: Plasma for cfDNA and CK analysis was collected at admission, at induction of anesthesia, postsurgery (time 0) and at 6, 12, 24, 36, 48, 60, and 72 hours after surgery. RESULTS: The biological half-life of plasma cfDNA and CK were 5.64 hours (95% confidence interval [CI 95], 4.36-7.98 hours) and 28.7 hours (CI95, 25.3-33.3 hours), respectively. In the hemilaminectomy group, cfDNA concentrations differed significantly from admission at 6-12 hours after surgery. Creatine kinase activity differed among the surgical groups and reached a peak 6 hours after surgery. In the ovariohysterectomy and CCLR groups, plasma CK activity 72 hours after surgery did not differ from admission activity of the ovariohysterectomy group. In contrast, in the hemilaminectomy group, plasma CK activity after 72 hours did not return to the ovariohysterectomy group admission activity. CONCLUSIONS AND CLINICAL IMPORTANCE: Plasma CK activity has a longer biological half-life than previously thought. In contrast to plasma CK activity, cfDNA has a short half-life and could be a useful marker for peracute severe tissue injury.

Etiological differences between subtypes of cutaneous malignant melanoma: Western Canada Melanoma Study.

From newly incident cases in Western Canada, 415 patients with superficial spreading melanoma (SSM), 128 with nodular melanoma (NM), and 56 with lentigo maligna melanoma (LMM) were interviewed, with age- and sex-matched controls chosen from the general population. The associations of these 3 subtypes with pigmentation, skin reaction to sun, different types of sun exposure, sunburn, and suntan were assessed. Compared to the other types, LMM occurred in older patients, and 75% of lesions occurred on the head and neck: It was less strongly related to pigmentation factors, intermittent sun exposure, and skin reaction to sun. The associations of SSM and NM with pigmentation, chronic sun exposure, skin reaction, and suntan were very similar: Both were associated with intermittent sun exposure, but SSM was more strongly related to vacation exposures than was NM. These results were compared with those from a similar Australian study. While LMM appears different in its etiology from SSM and NM, there is no strong evidence of major etiological differences between SSM and NM.

Radioiodide (131I) therapy for the treatment of canine thyroid carcinoma.

OBJECTIVE: To assess the efficacy of radioactive iodine treatment (131I) for canine thyroid carcinoma, as both the sole therapeutic modality and as an adjunct to surgery. DESIGN: Retrospective analysis of case records from the Gladesville Veterinary Hospital Nuclear Medicine Service, Sydney, between August 1988 and December 2001. CASE DETAILS: The records of 65 dogs with thyroid carcinoma were analysed according to therapy and outcome. Forty-three dogs received radioiodide therapy, either as the sole therapeutic modality (32) or as an adjunct to surgery (11). Radioisotope therapy consisted of one to three doses of 131I with a dose range of 555 to 1850 MBq. For analysis, dogs were divided into groups according to therapy: no treatment, surgery alone, surgery with radioiodide therapy or radioiodide therapy alone. Mode of therapy, dosage of 131I, clinical staging and age were all independently analysed according to survival to compare efficacy or predictive value respectively. RESULTS: When radioiodide therapy was used as an adjunct to surgery, median survival was 34 months. Censored median survival time for dogs that received radioiodide alone was 30 months. Dogs that did not receive treatment had a median survival of only 3 months. Log rank statistical analysis indicated that mode of therapy was significantly correlated with survival but that clinical stage of disease was not. CONCLUSION: The authors conclude that 131I therapy is effective at extending survival time, both as a sole therapeutic modality and as an adjunct to surgery, in dogs with invasive canine thyroid carcinoma. Incomplete surgical resection may not prolong survival in dogs also receiving 131I therapy, however surgical resection with curative intent should be recommended as the first line of therapy for mobile thyroid carcinomas. Radioisotope therapy can be recommended for cases where surgery alone is considered unlikely to be curative because of metastatic disease or local invasion, or for cases where surgery has been attempted but complete surgical removal has not been achieved.

Surgical repair of humeral condylar fractures in New Zealand working farm dogs - long-term outcome and owner satisfaction.

AIM: To report the long-term outcome, return to work and owner satisfaction, for working farm dogs in New Zealand following surgical repair of humeral condylar fractures. METHODS: A retrospective study of working dogs that had undergone surgical repair of one or more condylar fractures of the humerus was undertaken by searching the medical records of two referral veterinary clinics. The inclusion criteria were working dogs that had undergone open surgical reduction and internal fixation of a fracture of one or both humeral condyles. The ability of the dog to work after surgery, persistence of lameness and the owners' degree of satisfaction with the outcome were assessed from answers to a questionnaire. RESULTS: Sixteen dogs met the inclusion criteria and had owner questionnaires completed at a median follow-up interval of 54 (min 3, max 121) months. Fifteen were working farm dogs (13 Heading dogs, including Border Collies, and two New Zealand Huntaways) and one dog was a cross-breed used for pig hunting. Four dogs had two fractures on separate occasions, of which three underwent surgery on both elbows at a median interval of 19 months. Of the 20 humeral fractures, 10 were lateral condylar, one was a medial condylar fracture and nine were dicondylar fractures. Of the 16 repairs with follow-up data, seven (44%) dogs could perform all expected duties following surgical repair, whilst a further eight (50%) could perform most duties although some allowances had to be made for some limitation of their performance. Of the 15 owners responding, 13 (87%) were satisfied or very satisfied with the outcome of surgery and felt the surgery was worth the expense. Post-operative complications requiring a second surgery occurred in 7/20 (35%) dogs, and all six dogs that received appropriate surgical revision returned to work. CONCLUSIONS: In this small case series, surgical repair of humeral condylar fractures in working dogs had a good prognosis with 15/16 of treated dogs returning to full or substantial levels of work. CLINICAL RELEVANCE: These data provide veterinarians with relevant information regarding the outcome and prognosis of surgery for clients whose working dogs have fractured a humeral condyle.

Genetic evaluation of the total hip score of four populous breeds of dog, as recorded by the New Zealand Veterinary Association Hip Dysplasia Scheme (1991-2011).

AIM: To use estimated breeding value (EBV) analysis to investigate the genetic trend of the total hip score (to assess canine hip dysplasia) in four populous breeds of dogs using the records from the New Zealand Veterinary Association (NZVA) Canine Hip Dysplasia Scheme database (1991 to 2011). METHODS: Estimates of heritability and EBV for the NZVA total hip score of individual dogs from the German Shepherd, Labrador Retriever, Golden Retriever and Rottweiler breeds were obtained using restricted maximum likelihood procedures with a within-breed linear animal model. The model included the fixed effects of gender, birth year, birth season, age at scoring and the random effect of animal. The pedigree file included animals recorded between 1990 and 2011. A total of 2,983 NZVA hip score records, from a pedigree of 3,172 animals, were available for genetic evaluation. Genetic trends of the NZVA total hip score were calculated as the regression coefficient of the EBV (weighted by reliabilities) on year of birth. RESULTS: The estimates of heritability for hip score were 0.32 (SE 0.08) in German Shepherd, 0.37 (SE 0.08) in Labrador Retriever, 0.29 (SE 0.08) in Golden Retriever and 0.52 (SE 0.18) in Rottweiler breeds. Genetic trend analysis revealed that only the German Shepherd breed exhibited a genetic trend towards better hip conformation over time, with a decline of 0.13 (SE 0.04) NZVA total hip score units per year (p<0.001). The genetic trends of total hip score for the remaining three breeds were not significantly different from zero (p>0.1). CONCLUSIONS: Despite moderate heritability of the NZVA total hip score, there has not been substantial improvement of this trait for the four breeds analysed in the study period. CLINICAL RELEVANCE: Greater improvement in reducing the prevalence of canine hip dysplasia may be possible if screening were to be compulsory as a requirement for registration of pedigree breeding stock, greater selection pressure were to be applied and selection of breeding stock made on the basis on an individual's EBV rather than the NZVA total hip score alone.

Regulation of lipid synthesis by the RNA helicase Mov10 controls Wnt5a production.

Expression of the Wnt ligand Wnt5a is frequently elevated in melanoma and is thought to be a critical regulator of cell movement during metastasis. However, the mechanisms regulating its expression are unknown. We find that the level of secreted Wnt5a varies by as much as 10-fold between cell lines and correlates more strongly with invasion than total cellular levels. Our results indicate that the RNA helicase Mov10 plays a role in Wnt5a synthesis and secretion. Inhibition of Mov10 increases secreted Wnt5a levels in melanoma cells by increasing Wnt5a synthesis and acylation. This is achieved by increasing fatty acid synthase (FASN) and stearoyl-CoA desaturase expression, leading to elevated levels of palmitoleoyl-CoA, required for Wnt ligand lipid modification and secretion. Melanoma tumors exhibit reduced expression of Mov10 compared with benign nevi and Mov10 levels inversely correlate with FASN levels in primary tumors. These results reveal a previously unappreciated role for aberrant lipid metabolism in regulating Wnt5a signaling that may be a critical step in melanoma progression.

Superfractionation in glioblastoma multiforme--results of a phase II study.

A sequential series of 30 patients who were referred to a cancer treatment hospital with glioblastoma multiforme were treated with superfractionated cobalt 60 gamma radiation, three treatments per day, 100 rad per fraction. Their survival was compared to that of a historical group of 90 patients who had been referred for the same disease. Survival of the study patients was significantly longer than the historical patients, both for those who underwent resection (48.6 weeks median survival vs. 35.1 weeks), and for those who did not (35.1 weeks vs. 11.7 weeks). A retrospective survey of the historical group led to the following conclusions about this group: 1. Survival for patients who were well enough to be referred was unchanged after steroids came into general use; 2. Younger patients (under 50 years) did not have a longer survival than older patients; 3. The size of the dose of irradiation did not affect survival over the range of doses employed; 4. The size of the treatment volume employed did not affect survival over the range of treatment volumes employed.

Metastatic extraskeletal myxoid chondrosarcoma. Successful therapy with interferon alfa-2b.

A patient with pulmonary metastatic extraskeletal myxoid chondrosarcoma (EMC), of unknown cause, responded dramatically to 16 months of therapy with interferon alfa-2b. This is the first report of a significant response of a patient with EMC to this novel treatment approach.

A histological study of the Shionogi adenocarcinoma 115 grown in male and female mice.

We have previously demonstrated that growth rate and morphology differ between androgen-responsive Shionogi mouse mammary tumours maintained in male and female mice. Furthermore, we can modulate the growth rate of these tumours in male mice by exposing the mice to psychosocial stressors. In the present study, we were interested in determining if tumours in male mice with a comparable growth rate to that in females, also had a morphology similar to that in females. SC115 tumours were examined using histochemical and immunohistochemical techniques. Tumours in male mice were easily distinguishable from tumours in female mice regardless of growth rate. Tumours maintained in female mice contained osteoid-like regions which stained positive for sialic acid and sulphate moieties. No such regions were observed in any of the tumours from male mice. In addition, although all tumours contained MSA (muscle specific actin)-positive and S100 protein-positive cells, these regions were more extensive in the tumours of female mice. This study suggests that tumour growth rate and morphology are independently regulated by the host environment.

A new histochemical technique of use in the interpretation and diagnosis of adenocarcinoma and villous lesions in the large intestine.

The periodic acid-thionin Schiff/potassium hydroxide/periodic acid-Schiff (PAT/KOH/PAS) procedure has been used to investigate the histochemical staining characteristics of the mucins found in adenocarcinoma and villous lesions of the large intestine. The 46 blocks examined represented 58 lesions from 37 patients, all of whom had had resections for carcinoma of the colon. tin sharp contrast to normal colon, none of the adenocarcinomas stained red with the PAT/KOH/PAS. With two exceptions the poorly and moderately differentiated adenocarcinomas stained blue, whereas of the well differentiated lesions half were blue and half purple. The malignant villous lesions demonstrated the same trends, although a larger percentage were purple. None of the benign lesions stained blue. It is suggested that malignancy in the colon is accompanied by an increase in blue staining in the PAT/KOH/PAS technique and that such staining may be of value in the interpretation of highly atypical adenoma where it might identify the onset of malignancy. This change in staining indicates a distinct alteration in the chemistry of the mucins which we interpret as a reduction in the degree of side chain O-acylation of their constituent sialic acids.

The Walton report and its subsequent impact on cervical cancer screening programs in Canada.

A summary and discussion of some of the important and controversial recommendations in the original Walton report of 1976 on cervical cancer screening programs in Canada are presented. The reactions to the report in Canada are briefly outlined, particularly as related to the frequency of screening. The subsequent modifications in the recommendations by the reconvened task force of 1980, in response to the concerns of the profession and to newly available data, are highlighted.