dental disorders

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.

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.

Recent clinical and post-mortem studies documented a high prevalence of dental disorders in donkeys, but less information appears to be available specifically about incisor disorders in donkeys. A study to investigate the prevalence of oral and dental disorders affecting incisor teeth was performed, in two endangered breeds of donkeys: the Mirandês Donkey and the Zamorano-Leonés Donkey, through a prospective cross-sectional study in 800 donkeys, divided in 7 age groups (ranging 0-34 years), in 86 villages inside their geographic area of distribution, thinking on welfare and genetic preservation issues. The 74% of donkeys suffer from incisors disorders, ranging from 56.8% in the youngest group to 90.3% in group 7. Craniofacial abnormalities (49.25%), abnormalities in the occlusal surface (21.63%), fractures (17%), periodontal disease (16.13%) and diastemata (14.38%) were the main disorders recorded. Incisors disorders are significant, presenting at a much higher prevalence when compared to other studies involving the incisor teeth of equids, affecting all ages but particularly in older animals. This study provide essential information in dentistry applied to donkeys but also highlighted the importance of regular dental care in endangered breeds, improving their welfare and preserving a unique genetic heritage.