Assessing Biogeography of Coffee Rust Risk in Brazil as Affected by the El Niño Southern Oscillation.

The El Niño Southern Oscillation (ENSO) is an oceanic-atmospheric phenomenon influencing worldwide weather and climate. Its occurrence is determined by the sea surface temperature (SST) anomaly of the 3.4 Niño region in the Pacific Ocean (5°N-5°S, 120°-170°W). El Niño (EN), Neutral (NT), and La Niña (LN) are the three possible phases of ENSO, respectively, for warm, normal, and cold SST anomaly. As in other regions around the world, weather in Brazil is influenced by ENSO phases. The country is the major coffee producer in the world, and production is strongly influenced by weather conditions, which affect plant yield, harvest quality, and interactions with pests and diseases. Coffee leaf rust (CLR), caused by the fungus Hemileia vastatrix, is a major cause of coffee yield and quality losses in Brazil, and requires fungicide spray applications every season. Because CLR is highly influenced by weather conditions, it is possible to use weather variables to simulate its progress during the cropping cycle. Therefore, the aims of this study were to estimate CLR infection rate based on a validated empirical model, which has daily minimum air temperature and relative humidity as inputs, and to assess the extent of ENSO influence on the annual risk of this disease at 45 sites in Brazil. Cumulative infection rates (CIR) were estimated daily from October to June of each growing season and location, based on the prevailing ENSO phase. Differences between the extreme phases (EN-LN) were assessed by the Two-One-Sided-Tests (TOST) method. Analysis of data from eight sites, located mainly in Paraná State, provided evidence of CIR differences between EN and LN phases (G1). Evidence of no difference of CIR between EN and LN was found in 18 sites (G2), whereas 19 sites showed no evidence of differences (G3) due to relatively large variation of CIR within the same ENSO phase. The G1 sites are located mostly in Southern Brazil, where ENSO exerts a well-defined influence on rainfall regime. In contrast, the G2 sites are mainly in Minas Gerais State, which is characterized as a transition region for ENSO influence on rainfall. The G3 sites are located between the northern region of Minas Gerais State and southern region of Bahia State, which is characterized by a subhumid climate that is usually very dry during winter, and where rainfall can vary up to 300% from one year to another, influencing relative humidity and resulting in a high CIR variability. Therefore, ENSO had a well-defined influence on CIR only in Paraná State, a region with minor importance for coffee production in Brazil. No ENSO influence was found in more northerly zones where the majority of Brazilian coffee is produced. This is the first evidence of ENSO-linked regional impact on the risk of coffee rust.

A microbiome analysis of equine peripheral dental caries using next generation sequencing.

BACKGROUND: Although, peripheral caries (PC) affects almost half of UK horses, no comprehensive microbiological study has been performed on this disorder. As a high proportion of oral bacteria cannot be conventionally cultured, molecular microbiological techniques such as Next Generation Sequencing are required to examine the complex oral bacteria community. OBJECTIVES: To identify the microbiota involved in equine PC, including comparing microbiota at the more commonly and severely affected three caudal cheek teeth with the less commonly affected three rostral cheek teeth. STUDY DESIGN AND METHODS: Equine dental plaque samples were collected from the palatal aspects of cheek teeth of 63 horses. DNA was isolated and amplified using PCR, targeting the V4 region of the 16S rRNA gene and Next Generation Sequencing of these gene amplicons was performed. The acquired data were processed and analysed using Mothur and R. RESULTS: Streptococcus species was the genus most commonly associated with equine PC, whereas Gemella species was the genus most associated with the control group. In a further analysis where the rostral and caudal cheek teeth were compared with each other and with the control group. Veillonella species was the most commonly associated genus with PC of the rostral cheek teeth, Streptococcus species was the most associated genus with the caudal cheek teeth, and Corynebacterium with the control group. MAIN LIMITATIONS: Some bacteria can have multiple heterogeneous copies of the 16S rRNA gene, which can affect the estimation of their relative abundance. CONCLUSIONS: Similar to caries studies in other species, acidogenic and aciduric microorganisms including Streptococcus species were found to be associated with equine peripheral caries.

A histological and ultrastructural study of equine peripheral caries.

BACKGROUND: Peripheral caries (PC) has recently been shown to affect over half of UK and Australian horses. OBJECTIVES: To examine affected cheek teeth histologically and ultrastructurally, to assess the possible route(s) of carious infection into the dental tissues and to further describe the pathological changes in affected teeth. STUDY DESIGN: Descriptive pathological study. METHODS: Four control and 16 cheek teeth with different grades of PC were examined grossly, histologically and by electron microscopy. RESULTS: Cariogenic bacteria from plaque entered peripheral cementum perpendicular to the sides of teeth alongside Sharpey's fibres or vascular channels or more horizontally alongside exposed intrinsic fibres and cemental growth lines. Subsequent intra-cemental bacterial spread created different patterns of caries including vertical and horizontal flake-like patterns; deep, large flask-shaped or smaller superficial ellipsoid-shaped lytic lesions. Cemental caries progressed to affect enamel, dentine and even pulp. Gross examination underestimated the degree of caries observed on histological evaluation. MAIN LIMITATIONS: No dental histories were available; all teeth were examined on a single occasion. CONCLUSION: Equine PC causes different patterns of cemental lesions that appear dependent on the route of cariogenic bacterial invasion. Progression of caries can lead to pulpitis and tooth loss. Gross examination can underestimate the true extent of caries.

Radiographic, computed tomographic, gross pathological and histological findings with suspected apical infection in 32 equine maxillary cheek teeth (2012-2015).

BACKGROUND: Equine maxillary cheek teeth apical infections are a significant disorder because of frequent spread of infection to the supporting bones. The accuracy of computed tomographic imaging (CT) of this disorder has not been fully assessed. OBJECTIVES: To compare the radiographic and CT findings in horses diagnosed with maxillary cheek teeth apical infections with pathological findings in the extracted teeth to assess the accuracy of these imaging techniques. STUDY DESIGN: Observational clinical study. METHODS: Thirty-two maxillary cheek teeth (in 29 horses) diagnosed with apical infections by clinical, radiographic and principally by CT examinations, were extracted orally. The extracted teeth were subjected to further CT, gross pathological and histological examinations. Four normal teeth extracted from a cadaver served as controls. RESULTS: Pulpar and apical changes highly indicative of maxillary cheek teeth apical infection were present in all 32 teeth on CT, but in just 17/32 teeth (53%) radiographically. Gross pulpar/apical abnormalities and histological pulpar/periapical changes were present in 31/32 (97%) extracted teeth. On CT, one tooth contained small gas pockets in the apical aspect of one pulp and adjacent periodontal space, however no pathological changes were found following its extraction. MAIN LIMITATIONS: The study is descriptive and is confined to a small number of cases. CONCLUSION: This study showed a 97% agreement between CT diagnosis of maxillary cheek teeth apical infection and the presence of pathological changes in the extracted teeth, confirming the diagnostic accuracy of CT compared with radiography for this disorder.

Evaluation of ex vivo restoration of carious equine maxillary cheek teeth infundibulae following debridement with dental drills and Hedstrom files.

An ex-vivo study was performed on vertically mounted equine maxillary cheek teeth that had caries of 30 infundibulae, using high and low speed contra-angle dental drills and Hedstrom files to debride infundibular food debris and carious dental tissues. This technique effectively debrided 27/30 infundibulae with a mean depth of 19mm (range 9.4-34.3mm) as assessed by computed tomographic (CT) imaging. The debrided infundibulae were treated with sodium hypochlorite, EDTA and a bonding agent, and then then filled in layers with endodontic restoration materials. Further CT imaging and direct examination of sectioned restored teeth showed 6/30 infundibulae, including three that were incompletely debrided, to have defects between the restoration and the infundibular wall/apex. Twenty-one of the remaining 24 infundibulae contained air bubbles, largely within restorations. It is concluded that the use of drills and Hedstrom files is effective in debriding carious infundibulae but improved techniques and materials are required to more effectively fill infundibulae with restorative material.

An epidemiological survey on the prevalence of equine peripheral dental caries in the United Kingdom and possible risk factors for its development.

BACKGROUND: Equine peripheral caries (PC) is an increasingly recognised disorder that causes premature wear of teeth and dental fractures and thus has major welfare implications. Little information is available on its prevalence or severity in UK horses and there are no proven associations with any risk factors. OBJECTIVES: To document the prevalence of PC over a wide area of the UK, assess its intraoral distribution and severity in affected horses and examine for potential risk factors for its development. STUDY DESIGN: Cross sectional study. METHODS: Experienced personnel were recruited for a UK wide dental survey on their patients during dental examinations. Established guidelines were used for grading PC. Frequency of PC occurrence was compared between teeth and dental arcades using McNemar's tests. Potential risk factors for PC were screened using univariable logistic regression prior to building a multivariable model. RESULTS: A total of 706 horses were examined by 25 participants, showing a 51.7% prevalence of PC (365/706). Some regional differences in prevalence were found. The PC primarily affected the cheek teeth with the 12 caudal being significantly more commonly affected than the 12 rostral cheek teeth. Most of the hypothesised risk factors including age, breed, sex, time at pasture and feeding of silage (haylage) were unproven. A limited association with moderate levels of concentrate feeding was observed. The presence of concurrent dental abnormalities were significantly associated with the likelihood of having PC. MAIN LIMITATIONS: Not all regions in UK were included and there may be inconsistencies between examiners. CONCLUSIONS: Peripheral caries is common in British horses, primarily affecting the caudal cheek teeth. There was limited evidence of an association between feeding and PC. The association between PC and concurrent dental disorders indicates that these should be addressed in affected horses.

Gingival Toll-like receptor and cytokine messenger RNA levels in equine periodontitis and oral health.

REASONS FOR PERFORMING STUDY: Equine periodontitis is a common and painful condition. However, the disease often goes unnoticed by owners and is thus a major welfare concern. The aetiopathogenesis of the condition remains poorly understood and has been investigated in few studies. The innate immune system is known to play an important role in human periodontitis, but its role in equine periodontitis has not been examined. OBJECTIVES: To quantify the messenger (m)RNA levels of Toll-like receptors (TLRs) and cytokines in gingival tissue from orally healthy horses and those affected by periodontitis. STUDY DESIGN: Observational study. METHODS: Gingival tissue samples were taken post-mortem from 13 horses with no clinical signs of oral disease and 20 horses with periodontitis. mRNA levels of TLR2, TLR4 and TLR9 and cytokines interleukin-1ß (IL-1ß), tumour necrosis factor-α (TNF-α), IL-4, IL-6, IL-10, IL-12, IL-17 and interferon-γ (IFN-γ) were determined using quantitative real-time PCR. The statistical significance of results was assessed using appropriate t tests. RESULTS: mRNA levels of all TLRs and cytokines were upregulated in equine periodontitis. Significant increases in mRNA levels of TLR2, TLR9, IL-4, IL-10, IL-12 (P≤0.05) and IFN-γ (P≤0.01) were observed for both unweighted and age-weighted analyses of diseased gingival tissue samples compared with healthy gingival samples. In comparisons of samples of periodontitis lesions with healthy gingival control samples from the same horse, significant increases in mRNA levels of TLR4, TLR9, IL-10, IFN-γ (P≤0.05), TLR2, IL-1ß and IL-12p35 (P≤0.01) were observed. CONCLUSIONS: This study has provided an initial insight into the involvement of the immune system in equine periodontitis. Increased mRNA levels of TLR2, TLR4 and TLR9 indicate substantial microbial challenge in diseased gingival tissue. A mixed Th1/Th2/Th17 cytokine response is produced in equine periodontitis. Further studies are required to more fully characterise the role of the innate immune system in this disease.

An anatomical study of the dorsal and ventral nasal conchal bullae in normal horses: Computed tomographic anatomical and morphometric findings.

REASONS FOR PERFORMING STUDY: Infection of the dorsal nasal conchal bulla and ventral nasal conchal bulla has recently been shown to cause clinical disease in horses, but the anatomy of these 2 structures is poorly documented. OBJECTIVES: To describe the anatomical features, dimensions and relationships to adjacent structures of the dorsal conchal bulla and ventra conchal bulla in normal horses using computed tomography (CT). STUDY DESIGN: Descriptive imaging study using cadavers. METHODS: Computed tomographic images acquired from 60 equine cadaver heads that were shown to be free of sinonasal disease were categorised into 3 age groups (0-5; 6-15; >16 years old). Linear and volumetric measurements and descriptive anatomical assessments of the dorsal conchal bulla and ventral conchal bulla were produced from these CT images and the anatomical relationships between the dorsal conchal bulla and ventral conchal bulla and the adjacent structures, particularly the maxillary cheek teeth, were examined. The associations between bullae dimensions with horse ages and skull dimensions were assessed using linear regression. RESULTS: Mean (range) dorsal conchal bulla measurements were: length 7.5 cm (4.6-14), width 1.9 cm (1.3-2.5), height 2.8 cm (1.8-4), volume 24 cm3 (5.9-50.5). Mean ventral conchal bulla measurements were: length 5.7 cm (2.5-8.5), width 1.6 cm (0.7-2.9), height 2.4 cm (0.8-3.7), volume 15 cm3 (0.4-30). In both dorsal conchal bulla and ventral conchal bulla, there were significant differences in sizes between the different age groups (smaller in younger animals). In the ventral conchal bulla, this was probably related to protrusion of the large dental alveoli of younger horses into the lateral nasal cavity. Measures of bullae size and volume were significantly associated with head size. The anatomical positions (rostro-caudal boundaries) of the dorsal conchal bulla and ventral conchal bulla were closely associated with specific maxillary cheek teeth. CONCLUSIONS: Computed tomography was a useful technique to establish the linear and volumetric dimensions of the nasal conchal bullae in normal horses. Both dorsal conchal bulla and ventral conchal bulla sizes increased with animal age. Relatively consistent anatomical relationships were shown between the rostral and caudal limits of the bullae and certain maxillary cheek teeth, which would be of diagnostic value with conventional radiography and act as landmarks in the surgical treatment of nasal bulla disease.

Orthodontic correction of overjet/overbite ('parrot mouth') in 73 foals (1999-2013).

REASONS FOR PERFORMING STUDY: There are limited reports on the efficacy of functional orthodontic correction of overjet or overbite in foals. OBJECTIVES: To report the outcome of using orthodontic tension bands in combination with an inclined plane biteplate in the treatment of overjet, with or without concurrent overbite, rates of correction of these 2 malocclusions and associated complications. And to examine factors associated with outcomes. STUDY DESIGN: Retrospective case series. METHODS: Clinical records for 73 foals treated at a single clinic, by the same surgeon were analysed. Overall change and rates of change in overjet and overbite were calculated. Associations between potential explanatory variables including age, severity of initial malocclusion and surgeon experience were examined using linear regression. RESULTS: Records for 73 foals (43 colts, 30 fillies) were evaluated. The median number of implant placements per animal was 2 (range 1-4). Of 61 cases with complete records, reduction in overjet and overbite dimensions were achieved in 95% and 90% of foals, respectively, with mean reductions in malocclusions of 9.9 and 8.4 mm, respectively. Complete reduction in overjet was achieved in 25% (15/61) and reduction of malocclusion dimensions to ≤5 mm (i.e. functionally corrected) was achieved in 51% (31/61). Increasing animal age was significantly associated with decreased total reduction in overjet and decreased rate of reduction in overbite. Increased original severity of overbite was significantly associated with increased rate of its correction. Short-term complications included intraoperative haemorrhage, transient facial nerve neuropraxia and irritation of the mare's udder by the brace. Longer-term complications included cheek teeth diastema formation and incisor discoloration and maleruption. CONCLUSIONS: Using this technique, correction or improvement of these malocclusions is rapid, with minimal complications. Often more than one implant is required. Animal age at the start of treatment is associated with rate and amount of correction achievable, so initiating treatment at an early age is recommended.

Anatomical and histological study of the dorsal and ventral nasal conchal bullae in normal horses.

The morphology of the dorsal conchal bulla (DCB) and ventral conchal bulla (VCB) are poorly described. The recent recognition that these bullae can become infected, causing chronic unilateral nasal discharge, has stimulated interest in these structures. Fourteen cadaveric horse heads were transected sagittally midline and dissected to expose the nasal conchal bullae. The dimensions of each bulla, the number and orientation of drainage apertures, and cellulae septae were recorded. Randomly selected samples were examined histologically. The mean DCB and VCB lengths were 78  and 57 mm, respectively; equivalent to 13.9 per cent and 10.2 per cent of skull length, respectively. The mean DCB and VCB heights were 29  and 28 mm, respectively; equivalent to 5.2 per cent and 5 per cent of skull length, respectively. The DCB was larger than the VCB, containing more septae, cellulae and drainage apertures. No communications were identified between the bullae and the immediately adjacent paranasal sinuses. Histology revealed that the bullae consist of ciliated, pseudostratified, columnar epithelium over glandular submucosa often overlying turbinate bone and, variably, hyaline cartilage. This more detailed description of equine DCB and VCB anatomy will hopefully facilitate successful treatment of their disorders.

Clinical Research Abstracts of the British Equine Veterinary Association Congress 2015.

REASONS FOR PERFORMING STUDY: The morphology of the dorsal (DCB) and ventral (VCB) nasal conchal bullae, including their cellulae, drainage and histology, are poorly described. The recent recognition that these bullae can become infected, causing chronic unilateral nasal discharge has stimulated interest in these structures. A more complete understanding of their anatomy would be useful in the diagnosis and treatment of their disorders. OBJECTIVES: To document the structure, drainage and histology of the equine DCB and VCB. STUDY DESIGN: Descriptive. METHODS: Fourteen fresh cadaveric horse heads, were transected sagittally midline and dissected to expose the nasal conchal bullae. The dimensions of each bulla, the number of drainage apertures, the number of cellulae and orientation of the septae were recorded. Representative samples were collected for histopathology. RESULTS: The mean lengths of the DCB and VCB were 77.7 mm (range 48-105 mm) and 57.1 mm (range 34-86 mm) respectively; equivalent to 13.8% and 10.2% of skull length, respectively. The mean widths of the DCB and VCB were 28.5 mm (range 21-35 mm) and 28.2 mm (range 13-41 mm) respectively; equivalent to 5.1% and 5% of skull length respectively. The median number of drainage apertures from the DCB and VCB were 2 and 1 respectively. The median number of cellulae within the DCB and VCB were 3 and 2, respectively. No communications were identified between the DCB and VCB and the adjacent paranasal sinuses. Histology revealed that the bullae consisted of ciliated, pseudostratified, columnar epithelium supported by a glandular submucosa often overlying turbinate bone and, variably, hyaline cartilage. CONCLUSIONS: The morphology of the equine nasal conchal bullae is quite variable. The DCB is generally a more complex structure than the VCB, containing more septae, cellulae and drainage apertures. This more detailed description of DCB and VCB anatomy will hopefully facilitate successful treatment of their disorders. Ethical animal research: Research ethics committee oversight not currently required by this conference: the study was performed on material obtained from an abattoir. SOURCE OF FUNDING: None. Competing interests: None declared.

Empyema of the nasal conchal bulla as a cause of chronic unilateral nasal discharge in the horse: 10 cases (2013-2014).

REASONS FOR PERFORMING STUDY: Empyema of the nasal conchal bullae has recently been identified in horses suffering from chronic unilateral nasal discharge. The diagnosis and management of such cases has not been reported previously. OBJECTIVES: To describe the diagnosis and treatment of cases suffering from empyema of the nasal conchal bullae and report the frequency of diagnosis from a population of horses referred for head computed tomography (CT). STUDY DESIGN: Retrospective case review. METHODS: Records from cases diagnosed with nasal conchal bulla disease using CT were reviewed. RESULTS: Abnormalities of the nasal conchal bullae were identified by CT in 10 cases (8 ventral conchal bulla, 2 dorsal conchal bulla), from 102 equine head CT examinations. Eight cases were subsequently treated at the study clinic, 7 of which had concurrent paranasal sinus disease. In 3 cases, fenestration of the ventral conchal bulla per nasum facilitated drainage and clearance of empyema. CONCLUSIONS: Disease of the conchal bullae should be considered as a potential cause of chronic unilateral nasal discharge in horses. Clearance of empyema within these bullae is unlikely to occur through lavage of the paranasal sinuses alone. Where necessary, fenestration of the bulla allows physical removal of infected material.

Critical evaluation of ex vivo restoration of carious equine maxillary cheek teeth infundibulae following high-pressure gas and micro-particle abrasion.

Infundibular caries of the equine maxillary cheek teeth is an important disorder that can lead to dental fracture or apical infection. Treatment by removing food debris and carious dental tissue from affected infundibulae using high-pressure abrasion with aluminium hydroxide micro-particles, followed by filling the cleaned defect with endodontic restorative materials is a recommended treatment. However, although anecdotally considered a successful treatment option, there is currently no objective evidence to support this claim. Forty maxillary cheek teeth (CT) that contained 55 infundibulae with caries (mainly grade 2) were extracted post-mortem from 21 adult horses. Five of the CT were sectioned prior to treatment to facilitate visual examination of the carious infundibulae. The remaining carious infundibulae were cleaned using high-pressure abrasion with aluminium hydroxide particles and five CT were sectioned to assess the efficacy of this cleaning process. The remaining 30 CT containing 39 carious infundibulae were then filled with a composite restorative material. The efficacy of this restoration was assessed by computed tomography imaging followed by direct visual examination after sectioning the teeth. Only 46% (18/39) of restored infundibulae, all with shallow (mean 9.6 mm deep) defects, were fully cleaned of food debris and carious material, and filled with restorative material to their full depth. Of these 18, 11 had peripheral defects around the restoration, leaving just 18% (7/39) of restorations without any gross defects. The remaining 54% (21/39) of infundibulae (mean depth of infundibular caries defect, 18.3 mm) still contained food debris and/or carious material in more apical locations, with infundibulae with the deepest caries defects being the least effectively cleaned. The findings of this study indicate that high-pressure micro-particle abrasion is only effective in cleaning food debris from shallow, carious CT infundibulae and consequently, the majority of subsequent infundibular restorations are imperfect.

Characterisation of palatal dysfunction after laryngoplasty.

REASONS FOR PERFORMING STUDY: Dorsal displacement of the soft palate (DDSP) in the horse has been previously described as intermittent, typically occurring at fast exercise; or persistent, seen at rest. Dorsal displacement of the soft palate has recently been reported following laryngoplasty (LP) and can be associated with continued poor performance and respiratory noise. OBJECTIVES: The current study aimed to characterise the DDSP diagnosed post LP. STUDY DESIGN: Cross-sectional study. METHODS: Owners/trainers of horses undergoing LP at one institution over 6 years were contacted to determine the horse's progress and willingness for re-examination. The horses were examined at the rest, walk, trot and canter with an overground exercising endoscope. A GPS-equipped watch was carried to obtain maximal exercising speeds. Videos of horses with DDSP were reviewed to determine frequency and duration of DDSP and swallowing events at the various gaits. RESULTS: Exercising endoscopy was performed in 41 of the 89 horses that had undergone LP. Nineteen of the 41 horses were diagnosed with DDSP at exercise, of which 7/41 also had DDSP at rest. No difference was detected in the percentage of total time spent displaced at each gait (P = 0.67), or in the frequency of new DDSP events per minute between each gait (P = 0.10), or in the frequency of swallowing events per minute between each gait (P = 0.52). The majority of horses displaced at various times throughout each gait. Dorsal displacement of the soft palate was most commonly solely induced spontaneously and always corrected with a swallow. The maximum speed achieved was 8.3 m/s. CONCLUSIONS: Dorsal displacement of the soft palate was common following LP and it appears to be induced at slower gaits than DDSP that has previously been described. It also occurred at various times throughout each gait and did not always occur persistently at rest. POTENTIAL RELEVANCE: These findings suggest horses undergoing LP may be more prone to DDSP and further investigations into the aetiology of post LP palatal dysfunction are warranted.

A long-term study on the clinical effects of mechanical widening of cheek teeth diastemata for treatment of periodontitis in 202 horses (2008-2011).

REASON FOR PERFORMING STUDY: Cheek teeth diastemata are a common cause of painful periodontal disease in horses, but there is limited objective information on their treatment. OBJECTIVE: To assess the long-term response to diastema widening in clinically affected horses. STUDY DESIGN: Retrospective study. METHOD: Medical records from cases of cheek teeth diastemata treated by diastema widening referred to the University of Edinburgh Equine Hospital from 2008 to 2011 were analysed. RESULTS: During this period, 302 horses were diagnosed with clinically significant cheek teeth diastemata, of which 202, median age 11 years, with severe associated periodontitis were treated by widening of 674 problematic diastemata; 89.8% between mandibular cheek teeth and 10.2% between maxillary cheek teeth, with a mean of 1.5 treatments performed per case. These 202 cases showed quidding in 76.2%; weight loss in 33.2%; bitting problems in 20.1% and halitosis in 10.9%, with 5.4% being asymptomatic. Follow-up of 92% of treated cases, a mean of 20.8 months after their initial treatment, showed that 72.6% had complete remission of clinical signs that was permanent (for the duration of this study) in 50.5% and temporary in 22%. A partial response was obtained in 17.2%, no response was obtained in 4.3%, and owners were unsure of response in 5.9%. Clinical improvement was sometimes delayed, with 19% taking >4 weeks following treatment for improvement. Inappropriate sites were burred in individual teeth of 6 horses, causing iatrogenic pulpar exposure in 2 cases, but following treatment none developed clinical signs of apical infection. CONCLUSIONS: Diastema widening is an effective but potentially invasive treatment for horses with cheek teeth diastemata with severe periodontitis. POTENTIAL RELEVANCE: Diastema widening by trained personnel is suitable for advanced cases of cheek teeth diastema, but many cases require repeated treatments.

Swellings of the angle of the mandible in 32 horses (1997-2011).

Disorders of the horizontal ramus (body) of the equine mandible are well reported, but there is minimal documentation of disorders of the angle of mandible. A retrospective examination of the records of Edinburgh University Equine Hospital (1997-2011) showed that 32 horses were referred due to swellings of the angle of the mandible. The aetiology of these swellings was identified in just 13/32 cases (41%) including fractures (n=2), traumatic, localised periosteal/cortical lesions (n=4), traumatic soft tissue lesions (n=2), neoplasia (n=3), and inflammation of the adjacent salivary gland (n=1) and masseter muscle (n=1). The remaining 19 (59%) cases without a definitive diagnosis showed two patterns of lesions. Twelve cases had localised periosteal/cortical lesions of the ventral aspect of the angle of mandible that were most likely traumatic in origin. The remaining seven undiagnosed cases without mandibular bony changes all had sinus tracts/chronic soft tissue infections on the medial aspect of the angle of the mandible which were believed to be caused by a draining retro-pharyngeal lesion in five cases. Surgical excision of abnormal soft tissues (if present) and bone curettage was the most successful treatment. It was concluded that the aetiology of swellings of the angle of the equine mandible are often obscure; most appear to be traumatic in origin, yet horses seldom develop gross fractures at this site due to the support of the dense surrounding musculo-tendinous structures. A smaller proportion are caused by draining retropharyngeal lesions that respond poorly to medical therapy, but respond well to surgical treatment.

Congenital defects of the soft palate in 15 mature horses.

REASONS FOR PERFORMING STUDY: Horses, usually foals, with a congenital defect of the soft palate have been reported infrequently, and most reports describe a surgical procedure to repair the defect. Results of conservative management have not been previously reported. OBJECTIVE: To describe 15 horses affected with soft palate defects that were presented for examination when mature. STUDY DESIGN: Retrospective case series. METHODS: Clinical records from horses identified as having been diagnosed with a soft palate defect when older than one year were reviewed retrospectively. Follow-up was obtained wherever possible. RESULTS: Nasal discharge, occasional coughing and abnormal respiratory noise at exercise were the most common reasons for presentation. Only one yearling had mild symptoms of aspiration pneumonia. Many were able to perform at least low-intensity ridden activities and 2 Thoroughbreds raced successfully without surgical treatment. Surgical correction was attempted in 3 horses but was only partially successful in 2. The other horses were not treated surgically and no deterioration in severity of clinical signs was reported in the long term. The prevalence of survival in this case series was 100%. CONCLUSIONS AND POTENTIAL RELEVANCE: This case series shows that some foals may survive to maturity with substantial congenital defects of the soft palate without displaying severe clinical signs. Given the published high incidence of morbidity and mortality associated with surgical treatment, this case series suggests that a reasonable alternative is to manage such cases conservatively, provided that they are not suffering from severe pneumonia or ill thrift and that their welfare is not compromised.

A clinical survey on the prevalence and types of cheek teeth disorders present in 400 Zamorano-Leonés and 400 Mirandês donkeys (Equus asinus).

Dental disease is now recognised as a major but often unrecognised disorder of equids, including horses and donkeys. However, very few large clinical studies have documented the prevalence and type of dental disease present in different equid populations and no dental studies have been reported in Zamorano-Leonés or Mirandês donkeys, two endangered donkey breeds. Clinical and detailed oral examinations were performed in 400 Mirandês and 400 Zamorano-Leonés donkeys in Portugal and Spain. It was found that just 4.5 per cent had ever received any previous dental care. Cheek teeth (CT) disorders were present in 82.8 per cent of these donkeys, ranging from a prevalence of 29.6 per cent in the <2.5-year-old group to 100 per cent in the >25-year-old group. These CT disorders included enamel overgrowths (73.1 per cent prevalence but with just 6.3 per cent having associated soft tissue injuries), focal overgrowths (37.3 per cent), periodontal disease (23.5 per cent) and diastemata (19.9 per cent). Peripheral caries was present in 5.9 per cent of cases, but inexplicably, infundibular caries was very rare (1.3 per cent prevalence); this may have been due to their almost fully foraged diet. The high prevalence of enamel overgrowths in these donkeys, most which never received concentrates, also raises questions about the aetiology of this disorder. This very high prevalence of CT disorders, especially in older donkeys, was of great welfare concern in some cases and emphasises the need for routine dental care in these cases on welfare grounds and in order to help preserve these unique breeds.

Genetic and virulence variability among Erwinia tracheiphila strains recovered from different cucurbit hosts.

The causal agent of cucurbit bacterial wilt, Erwinia tracheiphila, has a wide host range in the family Cucurbitaceae, including economically important crops such as muskmelon (Cucumis melo), cucumber (C. sativus), and squash (Cucurbita spp.). Genetic variability of 69 E. tracheiphila strains was investigated by repetitive-element polymerase chain reaction (rep-PCR) using BOXA1R and ERIC1-2 primers. Fingerprint profiles revealed significant variability associated with crop host; strains isolated from Cucumis spp. were clearly distinguishable from Cucurbita spp.-isolated strains regardless of geographic origin. Twelve E. tracheiphila strains isolated from muskmelon, cucumber, or summer squash were inoculated onto muskmelon and summer squash seedlings, followed by incubation in a growth chamber. Wilt symptoms were assessed over 3 weeks, strains were reisolated, and rep-PCR profiles were compared with the inoculated strains. Wilting occurred significantly faster when seedlings were inoculated with strains that originated from the same crop host genus (P<0.001). In the first run of the experiment, cucumber and muskmelon strains caused wilting on muskmelon seedlings at a median of 7.8 and 5.6 days after inoculation (dai), respectively. Summer squash seedlings wilted 18.0, 15.7, and 5.7 dai when inoculated with muskmelon-, cucumber-, and squash-origin strains, respectively. In a second run of the experiment, cucumber and muskmelon strains caused wilting on muskmelon at 7.0 and 6.9 dai, respectively, whereas summer squash seedlings wilted at 23.6, 29.0 and 9.0 dai when inoculated with muskmelon-, cucumber-, and squash-origin strains, respectively. Our results provide the first evidence of genetic diversity within E. tracheiphila and suggest that strain specificity is associated with plant host. This advance is a first step toward understanding the genetic and population structure of E. tracheiphila.