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What controls diversity? The high diversity of many tropical taxa and subsequent decline in diversity away from the Equator has inspired many theories and much debate. Theories attempt to explain these patterns through a combination of one or several processes that may leave signatures in the functional, spatial and phylogenetic structure of species assemblages. Unfortunately, the testing of these theories has been hampered by a limited ability to separate the effects of multiple processes on observed patterns. In this thesis, I use recent advances in functional, spatial and phylogenetic methods in ecology to parse the contributions of multiple processes generating patterns of diversity in a hyper-diverse tree community in the Ecuadorian Amazon and the New World flora.In Chapter 1, I identify drought stress and herbivore pressure as key drivers of habitat associations and community structure in Amazonian trees using trait-based null models of community assembly. To do this I collected and analyzed leaf drought tolerance for 80 species and leaf lamina toughness for 454 species, both functional traits that are more tightly linked to a single assembly process than integrative traits such as specific leaf area.In Chapter 2, I ask if spatial aggregation in Amazonian trees is primarily determined by habitat associations, dispersal limitation or both processes using spatial point process modeling. I found that both processes were important drivers of aggregation for the majority of species, but that leaf traits such as drought tolerance were most predictive of habitat associations while seed mass predicted the size and density of species clustering independent of the abiotic environment.In Chapter 3, I test whether one proximate cause of latitudinal gradients in alpha diversity is a gradient in taxonomic or phylogenetic turnover, or beta diversity, with a large dataset of ~81,000 New World vascular plants. I found for both taxonomic and tip-weighted phylogenetic beta metrics that higher tropical diversity was associated with higher turnover. However, I found the opposite pattern for basal-weighted phylogenetic beta diversity, suggesting these metrics capture distinct aspects of biotic change across space. The results of this thesis suggest multiple processes combine and interact to create diversity patterns, but their influence can be separated with appropriate metrics.

Background: Canine hyperadrenocorticism (or Cushing’s syndrome) occurs due to a functional pituitary or adrenal tumour, resulting in excessive circulatory glucocorticoids, which produce the classical clinical signs in affected dogs. Although management of the disease traditionally focuses on treating these endocrine consequences, the pathology reflects an oncological disease with the possibility of progression of the underlying neoplasia. Surgical options for these tumours are now becoming increasingly available and successful. Aim of the article: This article covers how to distinguish between pituitary and adrenal hyperadrenocorticism as well as outlining the treatment options for this important disease in dogs.

Introduction Dogs treated for hypoadrenocorticism are monitored through analysis of their blood electrolytes. This is routinely performed with point-of-care analysers and doses of medications are adjusted based on the results. Objectives To investigate the performance of two point-of-care analysers (IDEXX Catalyst Dx and IDEXX VetStat) against a reference laboratory method for the measurement of blood sodium, potassium and chloride concentrations, as well as sodium: potassium ratios, in dogs diagnosed with and treated for hypoadrenocorticism. Methods Forty-eight dogs were enrolled into a prospective cross-sectional study. Paired blood samples were taken and tested on two point-of-care analysers and at a reference laboratory. Statistical analysis was then performed with Bland-Altman analysis and Passing-Bablok regression. The clinical effects of inaccurate electrolyte analysis were investigated. Results In total, 329 samples were tested on the Catalyst analyser, while another 72 samples were tested on the VetStat. Passing-Bablok regression identified both proportional and constant bias for some analytes. There was poor agreement between sodium and chloride concentrations on both analysers. Both analysers tended to give higher results than the reference method for all analytes, except for potassium when measured on the VetStat. Clinical significance There are inherent differences between the electrolyte concentrations measured by these two point-of-care analysers and reference laboratory methods in dogs with hypoadrenocorticism.

Objectives: The main aim of the study was to describe the features and diagnoses of a population of cats referred with pyrexia. Other aims were to report and evaluate the utility of clinical investigations performed, and describe any effect of treatment before referral on temperature at presentation and ability to make a diagnosis. Methods: Clinical records of cats with pyrexia (⩾39.2°C) documented at least twice were retrospectively reviewed. Cases were assigned to disease categories (infectious, inflammatory, immune-mediated, neoplastic, miscellaneous and no diagnosis [pyrexia of unknown origin, PUO]) based on diagnosis. The overall value of clinical investigations was assessed by classifying them as ‘enabling’, ‘assisting’ or ‘no assistance’ in achieving each diagnosis. The effect of treatment before referral was assessed for any association with temperature at presentation and ability to make a diagnosis (PUO vs other disease categories). Results: One hundred and six cases were identified. The most common cause of pyrexia was feline infectious peritonitis (22 cats, 20.8%) and the largest disease category was infectious (41/106, 38.7%). Inflammatory conditions were found in 19 (17.9%) cats, neoplasia in 13 (12.3%), miscellaneous causes in 11 (10.4%) and immune-mediated disease in six (5.7%). No diagnosis was reached in 16 (15.0%) cats, often despite extensive diagnostic investigations. Cytology and histopathology most often ‘enabled’ or ‘assisted’ in obtaining a diagnosis. Most cats (91, 85.8%) received treatment before referral, with antimicrobial treatment given to 87 (82.1%). Prior treatment before referral was not associated with temperature at presentation nor with success in establishing a diagnosis. Conclusions and relevance: This is the first study investigating causes of pyrexia in cats. Infectious diseases were most common and immune-mediated diseases were comparatively rare.

We agree that it is essential for all the veterinary associations to work collaboratively for the good of the profession, and that the BVA has an important role in harmonising veterinary policy and cross-professional initiatives. Although it is by no means perfect, the current system of operation …

New BSAVA President Ian Ramsey was born in Wales, spending his first 8 years in a famous little village on Anglesey called Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch. With his chemical engineer/civil servant father and maths lecturer mother, he then moved to London.

Alexander German, Ian Ramsey and Philip Lhermette address some of the concerns raised over calling pet obesity a disease and argue that this classification can bring many management opportunities.

Antimicrobial resistance (AMR) is a major threat to human and animal health. Studies in human healthcare have demonstrated that antibiotic stewardship programmes (ASPs) can be successful in achieving a sustained reduction in antibiotic use and rates of bacterial drug-resistance without negatively impacting patient outcome. ASPs for vets have been developed that highlight best practice guidelines – examples include the BVA’s seven-point poster and the British Small Animal Veterinary Association (BSAVA)/ Small Animal Medicine Society (SAMSoc) and British Equine Veterinary Association’s (BEVA) Protect Me posters. A key …

The objective of this study was to report clinical and clinicopathological abnormalities in canine spontaneous hyperadrenocorticism (HAC) and assess the relationship between patient size and those findings. A questionnaire was made available to primary care veterinarians to gather information on cases diagnosed with canine spontaneous HAC. Inclusion criteria were an adrenocorticotropic stimulation test and/or low-dose dexamethasone suppression test consistent with HAC. Exclusion criteria included concurrent systemic diseases, any clinical sign (CS) not typically associated with HAC, a urinary corticoid:creatinine ratio within reference interval, administration of steroids during the 3 mo before diagnosis, treatment with any drug causing CSs of HAC, and ongoing treatment for canine spontaneous HAC. Sixty-two cases were identified. The prevalences of various CSs were similar to those historically reported. No association between the patient weight and CSs was identified. The platelet count was negatively correlated to the weight (P = .005, r 2 = 0.3). Alanine aminotransferase (P = .016, r 2 = 0.17) and alkaline phosphatase (P = .05, r 2 = 0.0014) activities were positively correlated to the CS ratio. In this group of dogs, CSs were not significantly different between dogs ≤20 kg and dogs >20 kg. The prevalences of various clinical findings appeared to be similar to those historically reported. Dogs with more CSs tended to have higher alanine aminotransferase and alkaline phosphatase activities.

In this paper we report the results of a survey of financial literacy levels among Australian secondary school students. While key issues concerning financial literacy among adolescents is fairly well known, and governments see the urgency of addressing low levels of such literacy among a vulnerable cohort, less is understood about the variation of knowledge levels among young people. In this paper we identify the gap between urban and rural survey participants in respect of their financial literacy, and attempt to locate the contrasting knowledge levels in a setting that includes socioeconomic status and language background.

We are a mixture of volunteers and paid professionals who give our time to lead and support the veterinary professions, and we are extremely honoured to be able to do so. But we are increasingly concerned about the tone of some of the debates that are taking place in the veterinary world, particularly by the disparaging and demeaning language used against us or our colleagues. As leaders in the professions, representing various …

A subsea boosting system was implemented to increase the recovery from the Gulf of Mexico's Dalmatian field, which saw its first oil in 2014. Because today's challenging market requires a high focus on cost reduction, a great effort was undertaken to enable this project to materialize, ranging from the application of fit-for-purpose technology and a suitable contracting strategy. This is the industry's first project in which an alternative business model will enable the delivery and installation of a subsea boosting system. Furthermore, the Dalmatian project will represent the longest deepwater multiphase boosting stepout distance, applying high-voltage motor technology. The scope of the contract calls for the supply and installation of a subsea multiphase boosting system at 1,775-m water depth, including topside and subsea power and control system, as well as a 35-km combined power and control umbilical. The execution model enables a turnkey integrated project from design through supply, installation, and commissioning. This fit-for-purpose subsea boosting technology will improve the operator's ultimate recovery through a cost-effective and record breaking tieback. The innovative execution model that was applied further contributes to greater certainty of cost and return on investment. This paper addresses the technology and alternative business model that was used to make this project economically viable in a volatile and challenging market situation.

Background Hemoglobin A1c (HbA1c) provides a reliable measure of glycemic control over 2-3 months in human diabetes mellitus. In dogs, presence of HbA1c has been demonstrated, but there are no validated commercial assays. Objective The purpose of the study was to validate a commercially available automated immunoturbidimetric assay for canine HbA1c and determine an RI in a hospital population. Methods The specificity of the assay was assessed by inducing glycosylation in vitro using isolated canine hemoglobin, repeatability by measuring canine samples 5 times in succession, long term inter-assay imprecision by measuring supplied control materials, stability using samples stored at 4°C over 5 days and -20°C over 8 weeks, linearity by mixing samples of known HbA1c in differing proportions, and the effect of anticoagulants with paired samples. An RI was determined using EDTA-anticoagulated blood samples from 60 nondiabetic hospitalized animals of various ages and breeds. Hemoglobin A1c was also measured in 10 diabetic dogs. Results The concentration of HbA1c increased proportionally with glucose concentration in vitro. For repeat measurements, the CV was 4.08% (range 1.16-6.10%). Samples were stable for 5 days at 4°C. The assay was linear within the assessed range. Heparin- and EDTA-anticoagulated blood provided comparable results. The RI for HbA1c was 9-18.5 mmol/mol. There was no apparent effect of age or breed on HbA1c. In diabetic dogs, HbA1c ranged from 14 to 48 mmol/mol. Conclusions The assay provides a reliable method for canine HbA1c measurement with good analytic performance.

Blood glucose is maintained within a narrow range by the balance between intestinal absorption, glucose synthesis and glucose release from glycogen stores. Many diseases can affect this balance and result in hypoglycaemia; this can result in dramatic clinical signs due to neuroglycopenia. This article summarises the physiology of glucose regulation and the clinical signs of hypoglycaemia, its emergency treatment and its causes.

RECENTLY the most widely used treatment in the UK for canine hypoadrenocorticism (Addison's disease), fludrocortisone acetate (Florinef), has been taken off the market, to the consternation of many owners who have come to rely on this drug for their pets. A similar though not identical generic form of fludrocortisone is available but it is about six to seven times more expensive. Fortunately, a drug which is new to the UK but has been widely used in other countries, called desoxycortone pivalate (DOCP), is now available and is authorised for the treatment …

Each adrenal gland is composed of acortex and a medulla, which are functionally separate endocrine glands. The most common disorders affect the adrenal cortex and cause eitjer hyperadrenocorticism (HAC) or hypoadrenocorticism. This chapter considers canine hyperadrenocorticism, feline hyperadrenocorticism, canine hypoadrenocorticism, feline hypoadrenocorticism and other adrenal diseases. Readers will also find case examples included.

Summary Objective: This retrospective study describes the use of trilostane given once versus twice daily in dogs with hyperadrenocorticism (SID vs. BIDgroup) in separate clinical trials. Material and methods: The groups were compared over a six month period using laboratory findings, dose required to suppress post-ACTH cortisol, and clinical scores from owner and clinician questionnaires. Results: Ninety-three dogs enrolled the trials but for analysis of the final visit results only 56 dogs filled the inclusion criteria: 30 dogs in the SID-group and 26 dogs in the BID-group. Both treatment groups showed an improvement in clinical scores with time and no significant difference between them. In the BID-group post-ACTH cortisol concentrations went below 250 nmol/l sooner and in a higher proportion of dogs than in the SID-group.Twice-daily administration of trilostane also achieved a faster and more effective control for comparable daily doses. A higher individual tolerability (based on clinical scores) was found in the SID-group but there were no supporting laboratory findings. No dogs developed serious side-effects. Conclusion: This study reveals only small practical differences between once and twice daily trilostane administrations in treating hyperadrenocorticism. And the overall benefits of twice daily dosing have to be considered against the effect on the owners and their compliance with treatment.

Background: Trilostane is a recognized treatment for canine pituitary-dependent hyperadrenocorticism (PDH); however, its efficacy in dogs with adrenal-dependent hyperadrenocorticism (ADH) is unknown. Objectives: To examine factors that might influence survival in the medical management of ADH, with particular emphasis on treatment selection. Animals: Thirty-seven animals referred to 4 centers over a period of 12 years that had been diagnosed with ADH and treated with either trilostane (22/37), mitotane (13/37), or both (2/37). Methods: Retrospective analysis of clinical records. Results: There was no statistically significant difference between the survival times of 13 dogs treated only with mitotane when compared with 22 dogs treated only with trilostane. The median survival time for animals treated with trilostane was 353 days (95% confidence interval [CI] 95–528 days), whereas it was 102 days (95% CI 43–277 days) for mitotane. Metastatic disease was detected in 8 of 37 dogs. There was a significantly lower probability of survival for dogs with metastatic disease when compared with those without metastatic disease (P < .001). Conclusions and Clinical Importance: The choice of medical treatment for ADH may not have a major effect on survival times. However, the presence of metastatic disease considerably decreases survival time regardless of the choice of medical treatment.

Objectives: To describe the effect of trilostane on insulin requirements and serum fructosamine in dogs with diabetes mellitus (DM) and hyperadrenocorticism (HAC). Methods: Observational retrospective study of eight dogs. Results: Median fructosamine concentration at presentation was 401 μmol/L (range 244 to 554 μmol/L). Median insulin dose at presentation was 1·1 IU/kg/dose (0·4 to 2·1 IU/kg/dose) administered twice daily in five animals and once in three. Four dogs had their insulin dose prospectively reduced at the start of trilostane therapy. The HAC was controlled within 28 days in seven dogs. The remaining case was controlled by 17 weeks. Two dogs died within 40 days of starting trilostane. The median fructosamine concentration was 438 μmol/L (range 325 to 600 μmol/L) after stabilisation of the HAC. One case had a consistent reduction in serum fructosamine concentration over the first four months. The median insulin dose after stabilisation of HAC was 1·5 IU/kg dose (range 0·25 to 3·0 IU/kg/dose). Insulin requirements were reduced in two cases after treatment with trilostane. Four dogs required increased insulin doses. Clinical Significance: Insulin requirements and fructosamine concentrations do not consistently reduce during trilostane treatment for HAC. Prospective studies are required to provide recommendations regarding reductions in insulin doses with trilostane treatment.

Over the last 10 years, trilostane, a competitive inhibitor of steroid synthesis, is being widely used for the treatment of canine hyperadrenocorticism. Trilostane causes a significant but reversible decrease in cortisol production and a concomitant improvement in clinical signs in most dogs with this common condition. Side effects, though infrequent, can be serious: dogs treated with this drug require regular monitoring. This review summarizes current knowledge of the use of this drug with particular emphasis on its efficacy, safety, adverse reactions, and effects on endocrine parameters. Brief mention is made of its other uses in dogs and other species.

This article gives a short overview of the management of obesity in dogs and tells you more about the recent introduction of anti-obesity drugs. It is our opinion that no weight control programme in a veterinary practice can succeed without the active help of veterinary nurses. This article will help you understand the important principles underlying such a programme and answer some questions about setting up such a programme in a practice.

Polyuria (PU) and polydipsia (PD) are common presenting signs in dogs but less common in cats. Compensatory mechanisms that regulate water homeostasis mean that PU and PD always occur together. Most causes of PU/PD cause a primary PU with a secondary PD. There are a number of causes with some difference in the relative frequencies in dogs and cats (see Tables 1 and 2). LOGICAL APPROACH Most causes of PU/PD are serious diseases that require specific therapy. Therefore ‘symptomatic’ treatment is rarely appropriate and a logical series of investigative steps, if necessary undertaken over a series of veterinary consultations, is appropriate. The approach to PU/PD should be in this general order (which can be modified at any stage depending on the results) : 1. History 2. Physical examination 3. Urinalysis 4. Biochemistry (including T4 in cats) 5. Haematology 6. Hyperadrenocorticism screening test (less so in cats)

A 12-year-old male neutered Miniature Poodle with confirmed pituitary-dependent hyperadrenocorticism was treated with trilostane. After three doses, it developed clinical and laboratory changes suggestive of isolated hypocortisolism ('atypical hypoadrenocorticism'), which persisted and progressed for more than 3 months despite immediate withdrawal of the trilostane. The clinical signs of hyperadrenocorticism resolved without further trilostane. After 3 months, prednisolone treatment was started and the clinical signs of hypocortisolism resolved. Prednisolone therapy was required for more than 1 year. Ultrasonography initially demonstrated large hypoechoic adrenal cortices, typical of dogs with hyperadrenocorticism, which then became small and heteroechoic, consistent with the development of adrenal necrosis. Persistent isolated hypocortisolism has not been reported previously as a complication of trilostane therapy. The case is also remarkable for the very short duration of trilostane therapy that elicited this complication. Clinicians should be aware that trilostane therapy may result in adrenal necrosis, even in the very earliest stages of therapy, but prompt action can prevent a life-threatening situation.

Once it has been determined that a mating did take place and that the bitch was in heat then owners should be advised that pregnancy is possible (though by no means certain). Unless the client has a valid reason for keeping the animal intact then ovariohysterectomy performed two to three weeks after the end of vulval bleeding is the best recommendation. If the animal will potentially be used for breeding then several drugs are available that can terminate the pregnancy, however none is perfect. Many of the drugs that can be used to induce pregnancy termination have potentially serious side effects.

This article provides an overview of the management of canine obesity, with particular reference to the recent introduction of anti-obesity drugs and their role in weight management programmes. Obesity is best defined as an accumulation of excessive amounts of adipose tissue in the body. The term obese should be reserved for those cases whose current weight is 30% above their ideal (animals are termed overweight if they are 15 to 30% above their ideal). In most animals, obesity is the result of a simple imbalance between energy intake and energy expenditure. Numerous factors may influence the relative ease with which weight is gained, and these include genetics, age, neuter status, amount of physical activity, and the caloric content of the diet. In comparison with ‘simple’ obesity, medical causes such as hypothyroidism and hyperadrenocorticism, are comparatively rare (typically

Serum sodium:potassium (Na:K) ratios are often reported in biochemical studies of dogs, although their value has not been assessed. The aims of this study were to identify diseases associated with a low Na:K ratio in dogs and to compare their prevalence with the prevalence in dogs from the same referral hospital with normal Na:K ratios. A total of 238 dogs with a Na:K ratio less than 27 were identified from medical records. Sample contamination with edta was suspected in 74 cases (31 per cent) and these and two cases that had been supplemented with potassium were removed from the analysis. The remaining 162 cases and 147 control dogs were divided into five categories depending on the organ system affected. Among the cases there were significantly more in the endocrine category than among the control dogs. Hypoadrenocorticism was the most single common cause of a low Na:K ratio and affected 27 (16.7 per cent) of the cases. Other clinical problems associated with low Na:K ratios included different urogenital, cardiorespiratory and gastrointestinal diseases.

THE methods used to diagnose hyperadrenocorticism and distinguish the two forms of disease – pituitary-dependent versus adrenal-dependent – were described in the last issue of In Practice (September 2007, volume 29, pp 446-454). This article focuses on the treatment of the condition. Before treating any dog with hyperadrenocorticism, it is worthwhile having a detailed discussion with the owner about the costs, benefits and potential complications of the available therapies.