Advances in dental management in the equine geriatric patient: strategies for improved welfare.

Geriatric horses have a high prevalence of dental disease, which is a culmination of age-related dental changes and dental disease throughout the life of the horse that may have long-term consequences. Wear abnormalities, diastemata with periodontal disease, pulpitis and endodontic disease, infundibular caries, and equine odontoclastic tooth resorption and hypercementosis become more prevalent with age. Recognition of age-related dental disease at an early stage can help to treat and possibly preserve teeth for longer. With a natural decrease in masticatory efficiency, it is even more important to preserve teeth where possible and prevent any painful dental disease. Regular routine dental examination and maintenance will help to prevent many dental conditions such as wear disorders and possibly secondary diastemata. Successful treatment and management of most dental diseases are possible even in older patients and will ensure that we are able to maintain a high standard of welfare as horses age.

Long-term follow-up of equine incisor endodontic treatments using an orthograde technique.

OBJECTIVE: This retrospective clinical study was performed to determine the suitability and success rate of endodontic treatment of equine incisors presenting with apical and periapical disease. ANIMALS: All horses presented to a referral equine dental clinic between March 2013 and December 2019 specifically selected as candidates suitable for endodontic treatment were included in this study. METHODS: Initial clinical and radiographic presentation of incisor disorder cases suitable for endodontic treatment were recorded (88 incisors) and follow-up examination for long-term viability (8 months to 5 years) was performed in cases involving 32 incisors in total. RESULTS: A total of 68 horses with 88 incisors were included in this study for endodontic restorative treatment. Different dental materials were used, with a temporary 3-layered technique using calcium hydroxide apically and temporary cement and resin composite occlusally most commonly used at the first treatment. Complete obturation with resin composite was performed in 48% of the cases requiring second treatments (50 incisors). Follow-up examination involving 32 incisors showed that successful endodontic treatment was achieved in 75% of the teeth treated. CLINICAL RELEVANCE: Endodontic treatment of diseased incisors is a viable option in equid patients with a success rate comparable to humans in practice. The use of flowable resin composite as an obturation material has been shown to be successful at either the second treatment or in carefully selected patients at the first treatment.

Chronic pleuropulmonary fibrosis and elastosis of aged donkeys: similarities to human pleuroparenchymal fibroelastosis.

BACKGROUND: Donkey pulmonary fibrosis (DPF) is a spontaneous syndrome of aged donkeys with a high prevalence (35%). No previous detailed characterization of DPF has been performed. We sought to determine the similarities between DPF and recognized patterns of human pulmonary fibrosis. METHODS: Whole lungs were collected from 32 aged donkeys at routine necropsy. Gross examination revealed pulmonary fibrosis in 19 donkeys (DPF cases), whereas 13 (control cases) had grossly normal lungs. Eighteen whole inflated ex vivo lungs (11 DPF cases, seven control cases) were imaged with high-resolution CT (HRCT) scan, whereas the remainder were sectioned and photographed. Tissue samples were collected from all lungs for histopathologic evaluation using a standardized protocol. HRCT images and histology sections underwent independent blinded review. Lung tissue was analyzed for herpes virus, fungal hyphae, mycobacteria, and dust content. RESULTS: Ten of 19 DPF lungs were categorized as being consistent with pleuroparenchymal fibroelastosis (PPFE) according to previously defined histologic and imaging criteria. All 10 PPFE-like lungs had marked pleural and subpleural fibrosis, predominantly within the upper lung zone, with accompanying intraalveolar fibrosis and elastosis. Asinine herpesvirus was ubiquitously expressed within control and DPF lung tissue. No other etiologic agents were identified. CONCLUSIONS: Many cases of DPF share key pathologic and imaging features with human PPFE, a rare interstitial pneumonia. Consequently, further study of DPF may help to elucidate the etiopathogenesis of human PPFE.

A fresh look at the anatomy and physiology of equine mastication.

There have been many significant and interesting developments in equine dental anatomy during the past 20 years that are of major clinical significance in better understanding the physiology of equine mastication, the etiopathogenesis of some dental disorders, and their safe treatment. The many recent significant developments include descriptions of the enamel infolding of cheek teeth and of infundibular anatomy, including the frequent absence of cementum infilling in many infundibulae, which can lead to infundibular caries. Many important developments in equine dental anatomy are summarized in this article.

The gold standard of dental care: the geriatric horse.

Changes in normal equine dental anatomy with age result in dental disease specific to the geriatric horse. The culmination of dental disease throughout the life of a horse often results in advanced dental disease. Treatment of specific dental disease conditions has to be adapted for older horses to compensate for reduction in reserve crown and occlusal enamel. Ensuring oral comfort and maximizing masticatory ability are the mainstays of geriatric dental treatment. Recognition of dental disease common to older horses ensures that correct treatment is applied. Older patients often require long-term management changes, such as dietary modification, to manage dental disease effectively.

Selected health and management issues facing working donkeys presented for veterinary treatment in rural Mexico: some possible risk factors and potential intervention strategies.

The examination of 216 donkeys presented for treatment at the Donkey Sanctuary-World Horse Welfare-Universidad Nacional Autonoma de Mexico mobile clinics revealed a number of health and welfare problems. A general overview of the donkeys' health was made and showed that the median body condition score (BCS) in this population was 2.5. Underweight animals only accounted for 26% of the population. Females, 0-5-year-olds and >21-year-olds, were more likely to be underweight. When analysed, there was no correlation between faecal worm egg count (FEC) and BCS. The prevalence of strongyle infection as assessed by FEC was shown to be 80% with a median FEC of 600 eggs per gramme. Donkeys were assessed for body lesions and showed a high prevalence (71%), particularly in the facial region (54%). Analysis showed that mature animals (6-15 years old) were at increased risk of body lesions compared to older animals (16+ years old) as were donkeys with dental disease and those in particular villages. Risk factor analysis for lesions of the face showed that stallions and geldings are at increased risk as were donkeys wearing halters made from nylon rope. This study has identified areas for further investigation and potential areas where targeted interventions may be made to improve the health and welfare of working donkeys in Mexico.

Clinical dental findings in 203 working donkeys in Mexico.

Clinical dental examinations of 203 unsedated working donkeys in tropical and temperate climatic areas in Mexico revealed a high prevalence (62%) of dental disease with sharp enamel points present in 98% of the animals. More significant dental disorders (diastemata, 4%; overgrown teeth, 18%; worn teeth, 16%; missing teeth, 0.5%; displaced teeth, 1.5%; fractured teeth, 2%) with welfare implications that required immediate treatment were also present in 18% of donkeys. The high prevalence of buccal ulcers (14.3%) and calluses (13.3%) present in this population was believed to be due to the high prevalence of sharp enamel points in conjunction with the use of tight nose bands and head collars. Dental disease was significantly associated with age groups, but not with body condition score or to the climatic area where the donkeys lived. As part of more general examinations, 81% of donkeys that had faecal egg counts performed, had parasite burdens which mainly showed a moderate level of infection. This study concluded that dental disease is a welfare concern in working donkeys in Mexico.

The involvement of mast cells and mast cell proteinases in the intestinal response to equine cyathostomin infection.

Cyathostomins (Cyathostominae) are regarded as the most pathogenic equine nematode worldwide. These nematodes are difficult to control in equine populations due to emerging anthelmintic resistance and evasion of encysted larval cyathostomins to regular modern anthelmintics. Mast cells and their proteinases have been shown to play a role in the mammalian immune response to nematode infections. Involvement of mast cells and mast cell proteinases in the equine immune response to cyathostomin infection is proposed. A technique was established to perform immunohistochemical staining using polyclonal rabbit anti-equine mast cell proteinase-1 (eqMCP-1) and anti-equine tryptase on formalin-fixed large intestinal sections, from horses classified as cyathostomin positive and negative at the time of death based upon larval enumeration. Quantitative analysis of antibody labelled mast cells was used to detect mast cell proteinases in equine large intestinal sections positive and negative for cyathostomin larvae. This demonstrated an increase in equine tryptase labelled mucosal and submucosal mast cells in cyathostomin positive horses. This study has established an immunohistochemical technique to demonstrate mast cell proteinases in formalin-fixed large intestinal sections. This technique may be used to determine possible involvement of mast cells and their proteinases in the equine immune response to cyathostomin larvae. Further studies are required to define a specific role.