Erratum: One welfare: Linking poverty, equid ownership and equid welfare in the brick kilns of India - ERRATUM.

[This corrects the article DOI: 10.1017/S0962728600032504.].

P-glycoproteins play a role in ivermectin resistance in cyathostomins.

Anthelmintic resistance is a global problem that threatens sustainable control of the equine gastrointestinal cyathostomins (Phylum Nematoda; Superfamily Strongyloidea). Of the three novel anthelmintic classes that have reached the veterinary market in the last decade, none are currently licenced in horses, hence current control regimens focus on prolonging the useful lifespan of licenced anthelmintics. This approach would be facilitated by knowledge of the resistance mechanisms to the most widely used anthelmintics, the macrocyclic lactones (ML). There are no data regarding resistance mechanisms to MLs in cyathostomins, although in other parasitic nematodes, the ABC transporters, P-glycoproteins (P-gps), have been implicated in playing an important role. Here, we tested the hypothesis that P-gps are, at least in part, responsible for reduced sensitivity to the ML ivermectin (IVM) in cyathostomins; first, by measuring transcript levels of pgp-9 in IVM resistant versus IVM sensitive third stage larvae (L3) pre-and post-IVM exposure in vitro. We then tested the effect of a range of P-gp inhibitors on the effect of IVM against the same populations of L3 using the in vitro larval development test (LDT) and larval migration inhibition test (LMIT). We demonstrated that, not only was pgp-9 transcription significantly increased in IVM resistant compared to IVM sensitive L3 after anthelmintic exposure (p < 0.001), but inhibition of P-gp activity significantly increased sensitivity of the larvae to IVM in vitro, an effect only observed in the IVM resistant larvae in the LMIT. These data strongly implicate a role for P-gps in IVM resistance in cyathostomins. Importantly, this raises the possibility that P-gp inhibitor-IVM combination treatments might be used in vivo to increase the effectiveness of IVM against cyathostomins in Equidae.

Papaya latex supernatant has a potent effect on the free-living stages of equid cyathostomins in vitro.

The control of equid gastrointestinal nematodes in developed countries, in particular the cyathostomins, is threatened by high levels of anthelmintic resistance. In recent years, there has been increasing interest in the evaluation of traditional 'ethnoveterinary' medicines as alternatives to chemical anthelmintics. The cysteine proteinases (CPs), a group of enzymes derived from fruits such as papaya (Carica papaya), pineapple (Ananas comosus) and figs (Ficus spp.), have shown good efficacy against adult stages of a range of parasitic nematodes, in vitro and in vivo. The efficacy of CPs against cyathostomins remains to be explored. In this study, the efficacy of a crude preparation of CPs, papaya latex supernatant (PLS), against the free-living stages of cyathostomins was evaluated using two in vitro tests, the egg hatch test (EHT) and the larval migration inhibition test (LMIT). It was demonstrated that PLS had a potent effect in the EHT, with EC-50 values in the range of 0.12-0.22µM. At concentrations above 6.25µM the eggs did not develop, below this concentration the L1 developed but they lost integrity of the cuticle upon hatching. These effects were inhibited by pre-incubation of PLS with the CP inhibitor L-trans-epoxysuccinyl-l-leucylamido-(4-guanidino butane) (E64), indicating that CPs were responsible for the anti-parasitic activity. A dose-dependent inhibition of migration of third stage larvae (L3) in the LMIT was demonstrated at higher concentrations of PLS, with EC-50 values in the range of 67.35-106.31µM. Incubation of PLS with E64 prior to use in the LMIT did not reverse the anti-migratory effect, suggesting that CPs were not responsible for the reduced migration of cyathostomin L3 and that PLS also contains an additional active compound. This is the first report of PLS and/or CPs showing activity against the free-living stages of a parasitic helminth. In addition, it suggests that cyathostomins are highly sensitive to the effects of CPs and further evaluation of their efficacy against parasitic stages and in vivo are strongly indicated.

Essential oils in the management of the donkey louse, Bovicola ocellatus.

REASONS FOR PERFORMING STUDY: Chewing lice are widespread and clinically compromising parasites of livestock and equids. Their management is complicated by growing levels of resistance to commonly applied insecticides. Hence, the development of novel approaches to their control is of major clinical interest. OBJECTIVES: To assess the effects of incorporating the essential oils of tea tree and lavender into a grooming programme for populations of donkeys with natural infestations of Bovicola ocellatus in the UK and Ireland when louse populations were at their winter seasonal peak. STUDY DESIGN: In vivo field trial. METHODS: Suspensions of 5% (v/v) tea tree or lavender oil or an excipient only control were groomed into the coats of winter-housed donkeys (n = 198) on 2 occasions, 2 weeks apart. Louse counts were conducted before each application and 2 weeks later. RESULTS: After 2 applications, the groups groomed with lavender or tea tree oil suspensions had a significant reduction in louse intensity, with a mean decline in louse abundance of 78% (95% confidence interval 76-80%). Louse numbers in the groups groomed with excipient only either did not change or increased significantly. Donkey hair length had no effect on the decline in louse numbers. CONCLUSIONS: These results demonstrate that the inclusion of essential oil suspensions during grooming can be used to manage louse populations successfully.

An evidence-based approach to the evaluation of ethnoveterinary medicines against strongyle nematodes of equids.

Cyathostomins are the most important gastrointestinal nematode infecting equids. Their effective control is currently under threat due to widespread resistance to the broad spectrum anthelmintics licenced for use in equids. In response to similar resistance issues in other helminths, there has been increasing interest in alternative control strategies, such as bioactive plant compounds derived from traditional ethnoveterinary treatments. This study used an evidence-based approach to evaluate the potential use of plant extracts from the UK and Ethiopia to treat cyathostomins. Plants were shortlisted based on findings from a literature review and additionally, in Ethiopia, the results of a participatory rural appraisal (PRA) in the Oromia region of the country. Systematic selection criteria were applied to both groups to identify five Ethiopian and four UK plants for in vitro screening. These included Acacia nilotica (L.) Delile, Cucumis prophetarum L., Rumex abyssinicus Jacq., Vernonia amygdalina Delile. and Withania somnifera (L.) Dunal from Ethiopia and Allium sativum L. (garlic), Artemisia absinthium L., Chenopodium album L. and Zingiber officinale Roscoe. (ginger) from the UK. Plant material was collected, dried and milled prior to hydro-alcoholic extraction. Crude extracts were dissolved in distilled water (dH2O) and dimethyl sulfoxide (DMSO), serially diluted and screened for anthelmintic activity in the larval migration inhibition test (LMIT) and the egg hatch test (EHT). Repeated measures ANOVA was used to identify extracts that had a significant effect on larval migration and/or egg hatch, compared to non-treated controls. The median effective concentration (EC-50) for each extract was calculated using PROBIT analysis. Of the Ethiopian extracts A. nilotica, R. abyssinicus and C. prophetarum showed significant anthelmintic activity. Their lowest EC-50 values were 0.18 (confidence interval (CI): 0.1-0.3), 1.1 (CI 0.2-2.2) and 1.1 (CI 0.9-1.4)mg/ml, respectively. All four UK extracts, A. sativum, C. album, Z. officinale and A. absinthium, showed significant anthelmintic activity. Their lowest EC-50 values were 1.1 (CI 0.9-1.3), 2.3 (CI 1.9-2.7) and 0.3 (CI 0.2-0.4)mg/ml, respectively. Extract of A. absinthium had a relatively low efficacy and the data did not accurately fit a PROBIT model for the dose response relationship, thus an EC-50 value was not calculated. Differences in efficacy for each extract were noted, dependent on the assay and solvent used, highlighting the need for a systematic approach to the evaluation of bioactive plant compounds. This study has identified bioactive plant extracts from the UK and Ethiopia which have potential as anthelmintic forages or feed supplements in equids.

Seasonal infestation of donkeys by lice: phenology, risk factors and management.

A longitudinal study was undertaken over a 21 months period to examine the seasonal abundance of lice infesting donkeys, the risk factors which predispose donkeys to infestation and the effectiveness of louse management. All the lice seen were Bovicola (Werneckiella) ocellatus. A strong seasonal pattern, which was correlated with mean monthly temperature, was observed with higher prevalence and intensity in the cooler, winter months (October-March). Overall infestation in these animals was over-dispersed, suggesting that some individuals are strongly predisposed to infestation. Donkey age and mean hair length were characteristics which affected louse prevalence: older and younger donkeys and donkeys with longer hair harboured the highest numbers of lice. However, the practice of coat-clipping, to reduce the infestation, resulted in a lower louse prevalence only in the summer, suggesting that clipping is not an effective form of louse control in cooler months. Higher louse burdens were associated with larger areas of visible excoriation and hair damage, suggesting that B. ocellatus does adversely impact animal welfare. However, the ability of animal carers to estimate louse presence or absence accurately on an individual donkey was not sufficiently high to allow targeted selective treatment of heavily infested animals to be employed effectively. As animals are housed in closed herds these findings suggest that clipping in the summer and treating all animals with insecticide in late autumn, prior to turn-in may be an effective louse management strategy.

Expression of PGP 9.5 by enteric neurons in horses and donkeys with and without intestinal disease.

Intestinal motility disorders are an important problem in horses and donkeys and this study was carried out in order to evaluate the enteric neurons in animals with and without intestinal disease. Surplus intestinal tissue samples were collected from 28 horses undergoing exploratory laparotomy for colic. In addition, surplus intestinal samples from 17 control horses were collected immediately following humane destruction for clinical conditions not relating to the intestinal tract. Similar samples were also collected during routine post-mortem examinations from 12 aged donkeys; six animals were humanely destroyed for conditions related to the intestinal tract, while the remaining six were humanely destroyed for other reasons including dental and orthopaedic diseases. Tissue samples were fixed in formalin and immunohistochemical labelling was performed targeting the enteric neurons using a polyclonal antibody specific for the neuronal marker PGP 9.5. The distribution and density of neuronal networks were assessed qualitatively and semiquantitatively. There was strong PGP 9.5 expression in both the horse and donkey samples and labelling was detected throughout the tissue sections. In both species, PGP 9.5-immunoreactive nerve fibres were detected in all layers of the intestinal tract, both in large and small intestinal samples. Networks of enteric neurons were present in the donkey with a similar distribution to that seen in the horse. There was no demonstrable difference in enteric neuronal density and distribution in the groups of animals with intestinal disease compared with those without, apart from two (out of 28) horses with intestinal disease that showed a marked reduction in PGP 9.5 immunoreactivity. Apart from these two animals, this total cohort analysis differs from some previously observed findings in horses with intestinal disease and may therefore reflect the different pathophysiological processes occurring in varying intestinal conditions resulting in colic both in the donkey and the horse.

Control of the chewing louse Bovicola (Werneckiella) ocellatus in donkeys, using essential oils.

Infestations by lice can be a significant clinical and welfare issue in the management of large animals. The limited range of commercial pediculicides available and the development of resistance have led to the need to explore alternative louse management approaches. The results of in vitro and in vivo trials undertaken to control populations of the donkey chewing louse, Bovicola ocellatus (Piaget) (Phthiraptera: Trichodectidae) using the essential oils of tea tree (Melaleuca alternifolia) and lavender (Lavandula angustifolia) are reported here. Results of contact and vapour bioassays showed that 5% (v/v) tea tree and lavender oils resulted in > 80% louse mortality after 2 h of exposure. On farms, separate groups of 10 donkeys sprayed with 5% (v/v) tea tree and lavender oil as part of their usual grooming regime showed significant reductions in louse numbers compared with a control group (0.2% polysorbate 80 in water). These findings indicate that tea tree and lavender essential oils can provide clinically useful levels of control of B. ocellatus when used as part of a grooming routine and suggest that with further development could form the basis of an easy to apply and valuable component of a louse management programme for donkeys.

Hyperlipemia in a population of aged donkeys: description, prevalence, and potential risk factors.

BACKGROUND: Hyperlipemia is a common disorder of the donkey, with mortality rates of up to 80% reported. Such a poor prognosis makes prevention of this disorder or amelioration in the early stages crucial. OBJECTIVES: The objective of this study was to describe and determine the prevalence of hyperlipemia in a population of donkeys and to determine risk factors for development of the disease. ANIMALS: A total of 449 cases were investigated from a population of 3829 donkeys; donkeys were resident at The Donkey Sanctuary, a charity providing refuge for unwanted donkeys in the UK. Animals were selected on the basis of presence of clinical disease. METHODS: A retrospective case-control study design was used, and all donkeys presenting with hyperlipemia over a 4-year period were included. Each case was matched with 2 controls that had not suffered from hyperlipemia in the previous month. Multivariable analysis was carried out to determine risk factors. RESULTS: A total of 449 clinical cases of hyperlipemia were reported with an associated mortality rate of 48.5%. Concurrent disease was present in 72% of donkeys and was the greatest risk factor (OR = 76.98); others included cardboard bedding (OR = 3.86), movement (OR = 3.94), weight loss (OR = 6.4), dental disease (OR = 1.73), and concentrate feeding (OR = 1.87). CONCLUSIONS: This study shows that this population of donkeys in the UK often develops hyperlipemia, particularly in response to stress or primary illness, and provides useful insights in to health and management risk factors that may be addressed to decrease the risk of hyperlipemia both in the study population and in other similar donkey populations.

Retrospective analysis of post-mortem findings in 1,444 aged donkeys.

The aim of this study was to describe and report the prevalence of conditions found at necropsy examination of UK donkeys. Records from 1,444 donkeys over a 7-year period were included in the analysis. Sixty-one categories of post-mortem finding were identified from 9,744 observations. The four most prevalent conditions noted were dental disorder (78.7%), vascular disease other than aneurysm (60.9%), arthritis (55.4%) and foot disorder (44.8%). Gastric ulceration was found in 42% of the donkeys and gastrointestinal impaction in 18.6%. The most frequent combination of two post-mortem findings in the same animal was arthritis and dental disorder. The most common disorders were associated with age, body weight and/or body condition post mortem and, for some disorders, gender. For many of the post-mortem findings, crude associations were found between the presence of one finding and the odds of also having certain other post-mortem findings. This study is the first to summarize all conditions noted at necropsy examination for a large group of donkeys. The findings increase knowledge of diseases and conditions of this species and may be useful when investigating the relevance of various pathological conditions in the live animal.

Haemosiderin deposition in Donkey (Equusasinus) liver: Comparison of liver histopathology with liver iron content.

Histopathological examination was carried out on post mortem samples of liver from 12 donkeys (Equus asinus), aged 21-57 years (4 females, 1 stallion, 7 geldings). Variable amounts of haemosiderin were present in Kupffer cells, portal macrophages and hepatocytes in all cases. In all cases there was infiltration of connective tissue around portal tracts by variable numbers of inflammatory cells (lymphocytes, plasma cells and macrophages) but obvious portal fibrosis was present in only four animals. Subjective assessment of overall haemosiderin staining (including extent and intensity) generally reflected biochemical measurements of liver iron content (measured by an inductively-coupled plasma method) as well as quantitative histochemical measurements (using an image analysis package and sections stained with Perl's Prussian blue stain). Accumulation of hepatic iron in old donkeys was not directly related to other pathological changes and may be an incidental finding.

Haemosiderin deposition in Donkey (Equus asinus) livers: Comparison of quantitative histochemistry for iron and liver iron content.

Post mortem liver samples from 12 donkeys (Equus asinus) aged 21-57 years (4 females, 1 stallion, 7 geldings), were assessed chemically for copper and iron content on a wet weight basis and histologically for stainable iron. Chemical liver copper content ranged from 2.7 to 4.8µg/g (mean 3.5±0.05µg/g). Chemical liver iron content ranged from 524 to 5010µg/g (mean 1723±1258µg/g). Histochemical iron was measured morphometrically using a computer-based image analysis system; percentage section area staining for iron ranged from 0.84% to 26.69% (mean 10.82±8.36%). There was no clear correlation, within the wide range of iron values, between histochemically demonstrable iron and chemically measured iron content. No clear age-related increase was apparent for either parameter in these aged donkeys. The accumulation of iron in the liver of donkeys may represent a physiological haemosiderosis rather than pathological haemochromatosis.

Morphological study of tracheal shape in donkeys with and without tracheal obstruction.

REASON FOR PERFORMING STUDY: There is limited information on the gross tracheal morphology of donkeys with or without tracheal abnormalities. OBJECTIVES: To: 1) examine the morphology of tracheas of donkeys with and without clinical and/or post mortem evidence of tracheal obstruction; 2) record the cross-sectional dimensions and shapes of tracheal rings at fixed sites; and 3) document prevalence, sites and characteristics of detected tracheal abnormalities. METHODS: The tracheas of 75, predominantly aged (median age 30 years, range 7-48 years) donkeys that died or were subjected to euthanasia on humane grounds were examined. Five had severe dyspnoea due to tracheal obstruction (with intercurrent lung disease in 3), while 7 had post mortem evidence of severe tracheal airway obstruction. Every 5th tracheal ring was dissected free and the inner and outer vertical and transverse dimensions and cross sectional areas were measured. Each dissected ring was photographed and the shape of the trachea was classified as normal or, in one of 6 abnormal grades, according to the type and degree of structural abnormality present. RESULTS: The tracheas had a mean of 43 (range 34-50) tracheal rings that tended to be more oval in shape in the distal cervical region. Only 31.2% of rings examined had a circular to oval shape. Dorso-ventral flattening was present in 0.9% of tracheal rings, dorsal ligament separation in 24.4%, slight cartilage deformity in 26.0%, moderate cartilage deformity in 10.4%, marked cartilage deformity in 1.9% and miscellaneous other abnormalities in 4.9% of tracheal rings. The 12 donkeys with ante or post mortem evidence of tracheal obstruction had significantly increased tracheal abnormality grade in comparison to the remaining donkeys. CONCLUSIONS AND POTENTIAL RELEVANCE: Structural tracheal abnormalities are present in most old donkeys, but generally do not cause clinical problems in these sedentary animals unless intercurrent pulmonary disease is present.

Clinical dental examinations of 357 donkeys in the UK. Part 1: prevalence of dental disorders.

REASONS FOR PERFORMING STUDY: Dental disorders have a high prevalence in older donkeys and horses, but the nature and pathogenesis of many of these disorders have yet to be established. OBJECTIVES: The identification and determination of the prevalence of important dental disorders in different age groups in a large single population of donkeys, to establish a better understanding of the nature and pathogenesis of these disorders. METHODS: A prospective cross-sectional study was performed on the donkey population at The Donkey Sanctuary with detailed oral examinations of 357 donkeys within 7 different age groups (age range 2-53 years) recorded. RESULTS: The prevalence of dental disease in all donkeys was 73%, increasing in prevalence from 28% in the youngest to 98% in the oldest age group. There was an increase in prevalence of commonly recognised dental disorders with increasing age, such as: diastemata (3.8% in youngest to 86% in oldest group); missing teeth (0-56%); overgrown teeth (15-86%); worn teeth (8-84%); displaced teeth (0-38%); and periodontal disease (0-28%). CONCLUSIONS: There was a significant increase in the prevalence of dental disorders with increasing age with the largest significant increase for most dental disorders occurring in the 15-20 year age group. POTENTIAL SIGNIFICANCE: Most dental disorders significantly increase in prevalence in the 15-20 year age group and, therefore, prophylactic geriatric dental treatment in donkeys should be commenced from age 15 years.

Clinical dental examinations of 357 donkeys in the UK. Part 2: epidemiological studies on the potential relationships between different dental disorders, and between dental disease and systemic disorders.

REASONS FOR PERFORMING STUDY: Dental disease has been shown to be a risk factor for weight loss and colic in horses. No extensive clinical studies in donkeys have investigated the potential relationship between different dental disorders, or between dental disease and systemic disorders. OBJECTIVES: To determine possible associations between dental disease and body condition score, weight loss, the need for supplemental feeding and prevalence of colic in donkeys of all ages, and to gain a better understanding of the pathogenesis of dental disease by the determination of associations between different dental disorders. METHODS: A prospective cross-sectional analysis of clinical dental examinations of 357 donkeys in The Donkey Sanctuary, Sidmouth was performed. Other epidemiological factors such as estimated age group, body condition score, weight loss, medical history and supplemental feeding were also recorded, and multiple regression analyses were performed to determine possible associations. RESULTS: Donkeys from older age groups were more likely to have dental disease, poor body condition score and suffered previous colic episodes. The presence of dental disease was also significantly associated with weight loss, colic, low body condition score and the need for supplemental feeding. The presence of diastemata, periodontal disease, wave mouth, smooth mouth and step mouth are frequently associated with the presence of other dental disorders. CONCLUSIONS: In addition to oral-related pain, dental disease can cause significant systemic disorders and so has increased welfare implications in donkeys. Some dental disorders promote the development of other types of dental abnormalities and thus increase the severity of dental disease in individual animals. POTENTIAL SIGNIFICANCE: Effective treatment of dental disorders slows down the progression of dental disease and decreases the risk of developing some medical disorders such as colic and weight loss that are associated with dental disease.

Dimensions of diastemata and associated periodontal food pockets in donkey cheek teeth.

Equine cheek teeth (CT) diastemata often cause deep periodontal food pocketing and are therefore regarded as a painful dental disorder of equidae. However there appears to be no information available on the size or shape of these diastemata. This post mortem study examined 16 donkey skulls (mean age = 32-years) containing 45 CT diastemata to define the anatomical shape and dimensions of these diastemata, and of the associated periodontal food pockets that occur with this disorder. Diastemata were found to more commonly involve mandibular (56.0%) compared with maxillary CT (44.0%), and 71.0% of these diastemata had adjacent intercurrent dental disorders that may have predisposed donkeys to the diastemata. The median widths of all diastemata were 2.0-mm at the occlusal surface and 3.1-mm at the gingival margin, with no diferences in widths between the lateral or medial aspects of diastemata. Diastemata were defined as open (60.00%) or valve (40.00%) based on their gross appearance. This classification was confirmed to be accurate by measurements that showed valve diastemata to have an occlusal to gingival width ratio of 0.4, in contrast to open diastemata where this ratio was 1.07. Food was impacted in 89.0% of diastemata, but all diastemata had adjacent periodontal disease. Periodontal food pocketing was present adjacent to 76.0% of diastemata, more commonly on the lateral aspect (73.0% prevalence; mean pocket depth = 4.1-mm) than the medial aspect (47.0% prevalence; mean pocket depth = 2.4-mm). The depth of periodontal pockets of diastemata was not associated with the height of the erupted crowns of adjacent CT.

Necropsy survey of gastric ulcers in a population of aged donkeys: prevalence, lesion description and risk factors.

There is no information about the prevalence of gastric ulceration in donkeys or potential risk factors for its presence in donkeys. The donkey is a stoic, hardy animal that has not previously been thought to suffer from this disease. However, gastric ulceration was found to be a problem in a population of non-working UK donkeys resident at the Donkey Sanctuary and its prevalence was estimated by examining necropsy data over a 2-year period during 2005 to 2006. Associations with clinical and management factors were determined. In total, 426 donkeys were examined at necropsy to determine the presence of gastric ulceration. Lesions were described and scored according to a four-point scale. Management and clinical data from these donkeys were analysed to identify potential risk factors for the presence of gastric ulceration. Terminal blood samples were also studied to determine whether animals were exhibiting hyperlipaemia prior to death. Results showed that 41% (n = 174) of the donkeys studied had evidence of gastric ulceration at necropsy. Most (49%) of the ulcers were of a medium size (area of 2 cm2 - <10 cm2) and the most common site for ulcers was the margo plicatus. Of the donkeys examined, 18% had hyperlipaemia prior to or death or euthanasia and this was a risk factor for donkeys developing gastric ulceration; 62% of hyperlipaemia cases also displayed gastric ulceration (P < 0.001). Kidney disease was a potential risk factor (P = 0.02), with 74% of these animals having gastric ulceration. Donkeys that died or were euthanased due to respiratory disease were at a decreased risk of developing ulceration (P = 0.01) Donkeys fed a carbohydrate-based diet were more likely (P < 0.001) to have gastric ulceration than those fed a fibre-only diet, with 55% having gastric ulceration compared with 33% in the fibre-only group. This study has shown that gastric ulceration is commonly observed in donkeys at necropsy and may be extensive.

Post mortem survey of dental disorders in 349 donkeys from an aged population (2005-2006). Part 1: prevalence of specific dental disorders.

REASON FOR PERFORMING STUDY: Donkey dental disorders are being recognised with increased frequency worldwide and have important welfare implications; however, no detailed investigations of dental disorders in donkeys appear to have been published. OBJECTIVES: To determine the prevalence of specified dental disorders in donkeys by performing a prospective post mortem study on donkeys that were subjected to euthanasia or died for other reasons at the Donkey Sanctuary, UK. METHODS: Post mortem examinations were performed on 349 donkeys over an 18 month period, 2005-2006. The presence and extent of specified dental disorders were recorded and these data analysed to determine their prevalence and common locations. RESULTS: A high prevalence (93%) of disorders was noted in the population with a median age of 31 years. In particular, cheek teeth diastemata (85% prevalence) were very common, often associated with advanced periodontal disease. Other disorders observed included missing teeth (in 55.6% of donkeys), displaced teeth (43%), worn teeth (34%), local overgrowths (15%), focal sharp overgrowths (3%) and dental-related soft tissue injuries (8%). CONCLUSIONS AND POTENTIAL RELEVANCE: Aged donkeys have a high prevalence of significant dental disease, especially cheek teeth diastemata. These findings highlight the importance of routine dental examinations and prophylactic dental treatments to improve the dental health and welfare of donkeys.

Post mortem survey of dental disorders in 349 donkeys from an aged population (2005-2006). Part 2: epidemiological studies.

REASON FOR PERFORMING STUDY: Dental disorders have recently been recognised as having major clinical and welfare implications in donkeys. However, no investigation appears to have examined the association of dental disorders with managemental factors and any intercurrent illness. OBJECTIVES: To determine the association of dental disorders observed in a post mortem study with age group, body condition score, time since last dental treatment, feeding and the illness that necessitated euthanasia or caused death. METHODS: A prospective study documented the type and prevalence of dental disorders in 349 mainly aged donkeys (median estimated age of 31 years) that were subjected to euthanasia over an 18 month period in 2005'Aì2006. The estimated age, body condition score, supplemental feed status, time since last dental treatment and nature of the intercurrent disease that necessitated euthanasia or caused death were also recorded. Multivariable analysis was performed to examine associations of these factors with specific dental disorders and between specific dental disorders. RESULTS: There was a high prevalence (93.4%) of significant dental disease. Age group was significantly associated with the presence of dental disorders and an older age range was a high risk factor for the presence of cheek teeth (CT) diastemata. There was a significant association between the presence of CT diastemata and the concurrent presence of displaced, missing and worn CT. There was also a significant association between the presence of diastemata and colic. CONCLUSIONS AND POTENTIAL RELEVANCE: Aged donkeys have a high prevalence of dental disorders especially of CT diastemata. Dental disorders and, in particular, the presence of CT diastemata were significantly associated with colic. Routine, prophylactic dental treatments should be performed, especially in aged donkeys.