Malocclusions in the koala (Phascolarctos cinereus).

Malocclusions are a misalignment or incorrect positioning of the teeth when the upper and lower jaws close. These are poorly described in the koala and can result in irregular mastication which can have lifelong effects on body condition and oral health. A total of 370 koalas from two populations in Queensland (295) and one in South Australia (75) were examined for malocclusions. The prevalence of malocclusions in South Australian free-ranging koalas, captive Queensland koalas and Queensland free-ranging koalas was 39% (44), 30% (29) and 22% (29) respectively. Four types of malocclusion were identified based on severity of misalignment of the incisor/canine region, types 1, 2, 3 and 4. Maxillary overbite measurements of the molariform teeth were determined and these anisognathic values were then used to describe malocclusions within familial relationships in captive colonies. Captive koalas with a malocclusion had narrower mandibular width that ranged between 0.5 and 1% less than the normal measurements. The specific malocclusions reported in this study affected individuals by leading to tooth rotation, mobility and erosion with inefficient mastication of food and vegetation compaction. These changes increased the oral cavity pathology, by placing animals at risk of periodontal disease. There was evidence of familial links to malocclusion types in captive animals. Therefore captive breeding recommendations should consider known koala malocclusion traits to minimise their effect on future generations.

Predicting badger visits to farm yards and making predictions available to farmers.

The use of agricultural resources or environments by wildlife may result in opportunities for transmission of infections amongst wild animals, livestock and humans. Targeted use of biosecurity measures may therefore reduce disease risks, although this requires practical knowledge of where such measures would be most effective, and effective means of communicating risks so that stakeholders can make informed decisions about such investment. In parts of Europe, the European badger Meles meles may act as a wildlife reservoir for Mycobacterium bovis, the causative agent of bovine tuberculosis, and badger visits to farmyards may provide potential opportunities for transmission of M. bovis to cattle. Biosecurity measures are effective in reducing badger activity in farmyards, although it is unclear which farms should be targeted with such measures. We used cameras to monitor badger activity in 155 farmyards in south west England and Wales, and related variations in the presence and frequency of badger visits to farm characteristics. Badgers were recorded on camera in 40% of farmyards monitored. However, the frequency of visits was highly variable, with badgers recorded on >50% of nights in only 10% of farms. The presence of badgers in farmyards was positively associated with the density of badger setts, the number of feed stores and the number of cattle sheds, and negatively associated with the distance to the nearest active badger sett, the presence of a house/dwelling and the number of cattle housed on the farm. The frequency of visits was negatively associated with the distance to the nearest active badger sett and the number of cattle housed. Models predicted the presence/absence of badgers in farmyards with 73% accuracy (62% sensitivity, 81% specificity, using a cut off value of 0.265). Models could not distinguish between farms with low/high frequency of visits, although farms predicted as having badgers present typically had a higher frequency of visits than those that were not. We developed and present an interactive web based application: the Badger Farm Assessment Tool (BFAT), to allow users to enter the characteristics of a farm and generate a relative risk score describing the likelihood of badger visits.

How well do farmers know their badgers? Relating farmer knowledge to ecological survey data.

Knowledge of badger distribution is important for the management of bovine tuberculosis. At the farm level, typically the only information on badger activity available is from the farmers themselves. This study compares how well farmer perceptions of badger activity match data obtained from ecological surveys. Farmer estimates of numbers of badger setts (burrows) surrounding their farms were generally correlated with field survey results, but tended to be underestimates. Farmers correctly recorded 50 per cent of setts recorded in surveys, with larger setts and active setts more likely to be correctly recorded. Badger visits to farm buildings and yards were also monitored using surveillance cameras. The majority of farmers were aware of badger visits to their farm buildings, but in 22 per cent of cases farmers were not aware of badger visits. At the farm level, knowledge of badger activity will be useful in informing vets and animal health professionals of the potential risks of disease transmission, and hence directing management interventions. However, the tendency to underestimate activity, combined with a lack of detailed knowledge of sett locations, means that farmer estimates of badger activity should be interpreted with caution and in isolation may not be sufficient to inform management interventions.

Progressive facial asymmetry resulting from condylar osteochondroma - A case report detailing the resection, subsequent orthognathic intervention and custom joint replacement.

We discuss a 37 year old male - who presented with marked facial asymmetry and signs/symptoms suggestive of condylar hyperplasia. Imaging confirmed a large exophytic growth arising from the right mandibular condylar head. Treatment included tumour resection, orthognathic intervention and total joint replacement. The clinical presentation, pathology and treatment, along with a brief discussion are described in this report.

An abattoir survey of equine dental abnormalities in Queensland, Australia.

OBJECTIVE: A cadaver study to estimate the prevalence of dental disorders in horses presented at an abattoir in Queensland, Australia. METHODS: Cadaver heads at a Queensland abattoir were examined for the presence of dental abnormalities and categorised into age groups. The prevalence of abnormalities was analysed by binomial observation of observed proportion, Pearson's Chi-square test or Fisher's exact correlation test. Strength of association was evaluated using Cramer's V test. RESULTS: Heads from horses (n=400) estimated to be between 1 and 30 years of age were placed into four age groups. The most common abnormalities were sharp enamel points (55.3%) and hooks (43%). The highest frequency of dental diseases and abnormalities were in horses 11-15 years old (97.5%). CONCLUSIONS: Common abnormalities were found in all groups and the prevalence increased with age. This study suggests that all horses should have regular complete dental examinations to detect and treat dental disorders in order to limit more severe dental pathologies later in life.

Vaccination against tuberculosis in badgers and cattle: an overview of the challenges, developments and current research priorities in Great Britain.

Bovine tuberculosis (TB) is a significant threat to the cattle industry in England and Wales. It is widely acknowledged that a combination of measures targeting both cattle and wildlife will be required to eradicate bovine TB or reduce its prevalence until European official freedom status is achieved. Vaccination of cattle and/or badgers could contribute to bovine TB control in Great Britain, although there are significant gaps in our knowledge regarding the impact that vaccination would actually have on bovine TB incidence. Laboratory studies have demonstrated that vaccination with BCG can reduce the progression and severity of TB in both badgers and cattle. This is encouraging in terms of the prospect of a sustained vaccination programme achieving reductions in disease prevalence; however, developing vaccines for tackling the problem of bovine TB is challenging, time-consuming and resource-intensive, as this review article sets out to explain.

Sex-related heterogeneity in the life-history correlates of Mycobacterium bovis infection in European badgers (Meles meles).

Heterogeneity in the progression of disease amongst individual wild animals may impact on both pathogen and host dynamics at the population level, through differential effects on transmission, mortality and reproductive output. The role of the European badger (Meles meles) as a reservoir host for Mycobacterium bovis infection in the UK and Ireland has been the focus of intense research for many years. Here, we investigate life-history correlates of infection in a high-density undisturbed badger population naturally infected with M. bovis. We found no evidence of a significant impact of M. bovis infection on female reproductive activity or success, with evidence of reproduction continuing successfully for several years in the face of M. bovis excretion. We also found evidence to support the hypothesis that female badgers are more resilient to established M. bovis infection than male badgers, with longer survival times following the detection of bacterial excretion. We discuss the importance of infectious breeding females in the persistence of M. bovis in badger populations, and how our findings in male badgers are consistent with testosterone-induced immunosuppression. In addition, we found significant weight loss in badgers with evidence of disseminated infection, based on the culture of M. bovis from body systems other than the respiratory tract. For females, there was a gradual loss of weight as infection progressed, whereas males only experienced substantial weight loss when infection had progressed to the point of dissemination. We discuss how these differences may be explained in terms of resource allocation and physiological trade-offs.

Heterogeneity in the risk of Mycobacterium bovis infection in European badger (Meles meles) cubs.

The behaviour of certain infected individuals within socially structured populations can have a disproportionately large effect on the spatio-temporal distribution of infection. Endemic infection with Mycobacterium bovis in European badgers (Meles meles) in Great Britain and Ireland is an important source of bovine tuberculosis in cattle. Here we quantify the risk of infection in badger cubs in a high-density wild badger population, in relation to the infection status of resident adults. Over a 24-year period, we observed variation in the risk of cub infection, with those born into groups with resident infectious breeding females being over four times as likely to be detected excreting M. bovis than cubs from groups where there was no evidence of infection in adults. We discuss how our findings relate to the persistence of infection at both social group and population level, and the potential implications for disease control strategies.

Potential safety issues with blood flow restriction training.

The focal point of previous literature was establishing the efficacy of blood flow restriction training with respect to muscular strength, muscular hypertrophy, and muscular endurance. After mounting evidence supporting the efficacy of low-intensity blood flow restriction training, research has shifted to the overall safety of this training modality. The aim of this review was to summarize the research on the overall safety of blood flow restriction training, focusing on the cardiovascular system (central and peripheral), muscle damage, oxidative stress, and nerve conduction velocity responses compared with those observed with regular exercise. Although still sparse, the blood flow restriction training research thus far is promising with respect to safety outcomes. Individuals respond similarly to blood flow restriction training and to regular exercise; however, longer term studies are required to better understand the chronic effects of low-intensity blood flow restriction training and possible safety issues.

Commissurotomy for improving access to the oral cavity of the wombat.

Wombats are a grazing marsupial with a diet rich in silicates, which is highly abrasive and results in a higher rate of tooth attrition than in other grazing marsupials such as kangaroos. Any interference in the natural wear process, such as malocclusion or loss of teeth, causes overgrowth of teeth. The small mouth opening of the wombat makes access to the caudal mouth difficult and overgrowth of cheek teeth can be difficult to treat effectively. This case report describes a technique that greatly improves access to allow dental treatment of all overgrown teeth with minimal complications.

Using isolation-by-distance-based approaches to assess the barrier effect of linear landscape elements on badger (Meles meles) dispersal.

As the European badger (Meles meles) can be of conservation or management concern, it is important to have a good understanding of the species' dispersal ability. In particular, knowledge of landscape elements that affect dispersal can contribute to devising effective management strategies. However, the standard approach of using Bayesian clustering methods to correlate genetic discontinuities with landscape elements cannot easily be applied to this problem, as badger populations are often characterized by a strong confounding isolation-by-distance (IBD) pattern. We therefore developed a two-step method that compares the location of pairs of related badgers relative to a putative barrier and utilizes the expected spatial genetic structure characterized by IBD as a null model to test for the presence of a barrier. If a linear feature disrupts dispersal, the IBD pattern characterising pairs of individuals located on different sides of a putative barrier should differ significantly from the pattern obtained with pairs of individuals located on the same side. We used our new approach to assess the impact of rivers and roads of different sizes on badger dispersal in western England. We show that a large, wide river represented a barrier to badger dispersal and found evidence that a motorway may also restrict badger movement. Conversely, we did not find any evidence for small rivers and roads interfering with badger movement. One of the advantages of our approach is that potentially it can detect features that disrupt gene flow locally, without necessarily creating distinct identifiable genetic units.

A mechanistic approach to blood flow occlusion.

Low-Intensity occlusion training provides a unique beneficial training mode for promoting muscle hypertrophy. Training at intensities as low as 20% 1RM with moderate vascular occlusion results in muscle hypertrophy in as little as three weeks. The primary mechanisms by which occlusion training is thought to stimulate growth include, metabolic accumulation, which stimulates a subsequent increase in anabolic growth factors, fast-twitch fiber recruitment (FT), and increased protein synthesis through the mammalian target of rapamycin (mTOR) pathway. Heat shock proteins, Nitric oxide synthase-1 (NOS-1) and Myostatin have also been shown to be affected by an occlusion stimulus. In conclusion, low-intensity occlusion training appears to work through a variety of mechanisms. The research behind these mechanisms is incomplete thus far, and requires further examination, primarily to identify the actual metabolite responsible for the increase in GH with occlusion, and determine which mechanisms are associated to a greater degree with the hypertrophic/anti-catabolic changes seen with blood flow restriction.

Direct comparison of sensitivity encoding (SENSE) accelerated and conventional 3D contrast enhanced magnetic resonance angiography (CE-MRA) of renal arteries: effect of increasing spatial resolution.

PURPOSE: To assess the effect of attaining higher spatial resolution in contrast-enhanced magnetic resonance angiography (MRA) of renal arteries using parallel imaging, sensitivity encoding (SENSE), by comparing the SENSE contrast-enhanced (CE) MRA against a conventional CE-MRA protocol with identical scan times, injection protocol, and other acquisition parameters. MATERIALS AND METHODS: Numerical simulations and a direct comparison of SENSE-accelerated versus conventional acquisitions were performed. A total of 41 patients (18 male) were imaged using both protocols for a direct comparison. Both protocols used fluoroscopic triggering, centric encoding, breath-holding, equivalent injection protocol, and lasted approximately 30 seconds. RESULTS: Simulated point-spread functions were narrower for the SENSE protocol compared to the conventional protocol. In the patient study, although the SENSE protocol produced images with lower signal-to-noise ratio (SNR), image quality was better for all segments of the renal arteries. In addition, ringing of kidney parenchyma and renal artery blurring were significantly reduced in the SENSE protocol. Finally, reader confidence improved with the SENSE protocol. CONCLUSION: Despite a reduction in SNR, the higher-resolution SENSE CE-MRA provided improved image quality, reduced artifacts, and increased reader confidence compared to the conventional protocol.

Inhibition of matrix metalloproteinase-9 activity improves coronary outcome in an animal model of Kawasaki disease.

Kawasaki disease (KD) is the leading cause of acquired heart disease of children in North America. It is characterized by a massive immune activation and multi-system vasculitis, which evolves into a site-specific inflammatory response focused at the coronary arteries. Coronary artery (CA) inflammation leads to elastin breakdown, destruction of the vessel wall and aneurysm formation. We have demonstrated recently the pivotal role of tumour necrosis factor (TNF)-alpha-mediated matrix metalloproteinase (MMP)-9 activity in the pathogenesis of elastin breakdown in a murine model of KD, Lactobacillus casei cell wall extract-induced coronary arteritis. Using this model, we evaluated the in vitro effects of doxycycline, an antibiotic with MMP inhibitory function, in modulating key pathogenic stages of disease leading to CA damage. Doxycycline inhibits T cell activation and TNF-alpha production in peripheral immune cells, as assessed by thymidine incorporation and a TNF bioassay respectively. Additionally, doxycycline inhibits directly MMP-9 enzymatic activity derived from TNF-alpha-stimulated vascular smooth muscle cells as assayed by zymography. More importantly, in vivo treatment of Lactobacillus casei cell wall extract (LCWE)-injected mice with doxycycline reduces significantly the incidence of CA elastin breakdown and reduces loss of elastin. Therefore, doxycycline can mitigate TNF-alpha-induced MMP-9-mediated coronary elastin breakdown and improve coronary outcome. Agents with the ability to inhibit both inflammation and the downstream effects of inflammation, such as MMP-9 activity, offer a promising therapeutic strategy for the management of children with KD.

Micro magnetic resonance angiography of the finger in systemic sclerosis.

OBJECTIVE: To characterize vascular lesions in SSc disease with high-resolution magnetic resonance angiography (Micro-MRA) of the finger. METHODS: Eight SSc subjects and eight age- and sex-matched healthy controls were recruited for this study. Among the SSc subjects, the mean +/- s.d. age was 54.5 +/- 4.9 yrs, and the mean +/- s.d. duration of disease was 8.3 +/- 8.4 yrs. The numbers of SSc subjects that had telangiectasia, calcinosis and impaired finger flexion were 3, 2 and 3, respectively. The 2D time-of-flight micro-MRA was performed on a 3T clinical MRI scanner using a custom-designed finger coil with an in-plane resolution of 0.16 x 0.21 mm(2) and slice thickness of 1.2 mm. The data for the proper palmar digital artery lumen area, the number of visible dorsal digital veins and a semi-quantitative vascular score, which evaluates the overall integrity of digital vessels, were independently evaluated by two experienced reviewers who were blinded to the status of the subject. RESULTS: Micro-MRA detected significant differences in the digital vasculature between SSc subjects and healthy volunteers. The SSc subjects had a significantly decreased digital artery lumen area (0.13 +/- 0.06 vs 0.53 +/- 0.26 mm(2), P < 0.001), a reduced number of digital veins (0.63 +/- 1.06 vs 3.13 +/- 0.99, P = 0.001) and a lowered overall vascular score (1.75 +/- 1.04 vs 3.5 +/- 0.53, P = 0.001). The study also found that both the digital artery lumen area (Pearson's; r = -0.72, P = 0.044) and vascular scores (Spearman's; rho = -0.75, P = 0.047) of the SSc subjects were inversely correlated with the duration of the disease. CONCLUSIONS: Micro-MRA can be used to identify and quantitatively characterize the vascular disease in SSc fingers. The parameters derived from micro-MRA could potentially be used as prospective biomarkers for clinical evaluation.

Is Mycobacterium bovis in the environment important for the persistence of bovine tuberculosis?

Mycobacterium bovis is the causative agent of bovine tuberculosis (bTB) in cattle and wildlife. Direct aerosol contact is thought to be the primary route of infection between conspecifics, whereas indirect transmission via an environmental reservoir of M. bovis is generally perceived not to be a significant source for infection. Here, we report on the application of molecular technology (PCR) to quantify the prevalence of M. bovis in the environment and to explore its epidemiological significance. We show that the detectability of viable M. bovis at badger setts and latrines is strongly linked to the frequency of M. bovis excretion by infected badgers, and that putative M. bovis in the environment is prevalent on a large proportion of endemic cattle farms in Britain. These results raise important questions about the role of an environmental reservoir in bTB persistence.

Temperature changes in dental pulp associated with use of power grinding equipment on equine teeth.

OBJECTIVE: To quantify the temperature changes in the dental pulp associated with equine dental procedures using power grinding equipment. DESIGN: A matrix experimental design with replication on the same sample was followed to allow the following independent variables to be assessed: horse age (young or old), tooth type (premolar or molar), powered grinding instrument (rotating disc or die grinder), grinding time (15 or 20 seconds) and the presence or absence of water coolant. PROCEDURE: Sound premolar and molar teeth from a 6-year-old horse and a 15-year-old horse, which had been removed postmortem, were sectioned parallel to the occlusal plane to allow placement of a miniature thermocouple at the level of the dental pulp. The maximum temperature increase, the time taken to reach this maximum and the cooling time were measured (n=10 in each study). The teeth were placed in a vice and the instrument used on the tooth as per clinical situation. RESULTS: Significant differences were recorded for horse age (P < 0.001), instrument type (P < 0.001), grinding time (P < 0.001) and presence or absence of coolant (P < 0.001). There was no significant difference for tooth type. CONCLUSION: Thermal insult to the dental pulp from the use of power instruments poses a significant risk to the tooth. This risk can be reduced or eliminated by appropriate selection of treatment time and by the use of water irrigation as a coolant. The increased dentine thickness in older horses appears to mitigate against thermal injury from frictional heat.

Vaccinating badgers (Meles meles) against Mycobacterium bovis: the ecological considerations.

Bovine tuberculosis (TB) is a serious zoonotic disease, which despite a largely successful test and slaughter programme has persisted in cattle herds in parts of the UK. The badger (Meles meles) is widely considered to represent a significant wildlife reservoir for the transmission of Mycobacterium bovis to cattle, and has been the subject of a variety of culling strategies since the mid 1970s. Nevertheless, the incidence of herd breakdowns has continued to rise, and the efficacy of culling is currently the subject of a large-scale field trial. One potential alternative tool for the management of disease in wildlife populations is vaccination. However, the successful development of an effective vaccine and a strategy for its delivery will require careful consideration of the practical constraints imposed by ecological factors. In the current paper, we discuss relevant ecological and epidemiological characteristics of badger populations and practical aspects of vaccine delivery in the field.