horse

Hyperlipaemia is a disease resulting from excessive mobilisation of triglyceride stores such that plasma clearance processes become overwhelmed. Consequently increased plasma triglyceride concentrations (>5.6 mmol/l), visibly cloudy plasma and a sick, anorexic or hypophagic subject follow. Epidemiological studies have identified many predisposing and triggering factors and the attentive carer or veterinary surgeon should be alert to such risk factors so that the disease can be prevented, or at least identified and treated at an early stage. Hyperlipaemic subjects are invariably in a negative energy balance, and nutritional management therefore plays a central role in both the prevention and resolution of the disease.

Typhlocolitis was diagnosed in 40 aged donkeys at routine post mortem examinations subjected to euthanasia for colic-related clinical signs at The Donkey Sanctuary. Gross pathological changes included oedema, ulceration and haemorrhage involving the caecum and ventral colon. Histopathology indicated endoparasite and bacterial associated inflammation in 20 and 11 cases, respectively. Bacterial culture in 18 cases did not yield a definite aetiological agent. Other management and stress related factors were looked at to identify obvious risk factors. This report describes the clinical, biochemical and haematological parameters and pathological changes observed in 40 donkeys diagnosed with typhlocolitis.

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.

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.

A cross-sectional coprological survey in the regions of Ada, Akaki, Bereh and Boset, and a retrospective postmortem investigation were conducted to study the epidemiology of Parascaris equorum in donkeys and horses in Ethiopia. Faecal samples from 803 working donkeys and 402 horses were collected, and the numbers of worms recovered from 112 donkeys examined postmortem between 1995 and 2004 were analysed. There was a high prevalence of infection and faecal egg output of Parascaris equorum in both donkeys and horses, and the severity of the infection in donkeys was increased irrespective of their age. The prevalence of the infection in the donkeys was 51·1 per cent and in the horses 16·2 per cent, and the prevalence in the donkeys examined postmortem was 55 per cent. There was no significant difference between different age groups of donkeys in either the prevalence or the intensity of the infection. The prevalence of the infection was significantly higher in the Ada and Akaki regions than in the Bereh and Boset regions.

Parascaris equorum is an important parasite of young horses, particularly sucklings and weanlings (Russell 1948, Soulsby 1982, Austin and others 1990, Southwood and others 1998). The parasite has a worldwide distribution, and is usually present wherever horses are raised (Clayton 1986, Southwood and others 1998). It can reduce the growth rate of foals and cause occasional deaths due to intestinal obstruction or rupture (Dipietro and others 1983, Clayton 1986, Ryu and others 2004).

Parascaris equorum has also been reported in donkeys from various regions of the world (Tolliver and others 1985, Vercruysse and others 1986, Pandey and Eysker 1990, Ricci and Sabatini 1992, Burgu and others 1995, Daoud and Al-Alousi 1995, Feseha 1998, Lewa and others 1998, Getachew 1999, Kotwal and others 2000, Matthee and others 2002). However, most of these reports concern only small numbers of animals, and the information is rather fragmentary. There have been no specific studies of the epidemiology, pathogenicity and immunology of parascarid infections in horses and donkeys under the tropical weather conditions of Ethiopia. The aim of the present study was to investigate the epidemiology of this parasite in working donkeys and horses in Ethiopia by means of a cross-sectional coprological survey and retrospective postmortem examination findings.

Background

In the UK, there are thousands of donkeys being cared for by charities; however, little is known about the reasons for relinquishment or their previous health status, with even less information available in published literature. Such information could help to identify factors contributing to poor equine welfare and guide the development of appropriate educational resources.

Objectives

To describe the characteristics of the relinquished donkeys and to better understand the current preventative healthcare status of donkeys relinquished into The Donkey Sanctuary.

Study design

Cross‐sectional observational survey.

Methods

A total of 596 donkeys were admitted during a 30‐month period. Each had a health check at arrival; and previous management information was provided by the owner. Data were retrieved from The Donkey Sanctuary database, inputted into a specific Microsoft Access 2016 database then exported for analysis in IBM SPSS 19.0 for Windows®. Mules and ponies were excluded from the study.

Results

Many donkeys arrived without a valid passport (32.3%) or microchip (49.7%). Only 23.2% were fully protected against influenza and tetanus and 21.0% of the donkeys had no previous anthelmintic treatment history. Geriatric donkeys often suffered from moderate to severe dental disease in need of advanced treatment, and 43.9% had received no dental treatment within the last year. Overall 26.3% of donkeys were classed as overweight and 8.6% were obese. The median time since the last hoof trim was 10 weeks.

Main limitation

The health status of the studied donkeys may have been affected by the reasons for relinquishment, and associations require further investigation.

Conclusions

This study highlights the need for improving preventative healthcare in donkeys to ensure better welfare within the population.

Background

Factors affecting working equid welfare are wide-ranging and reflect cultural, economic and climatic conditions, the type of work equids are used for, and individual differences in the practices of their handlers. In Mexico working equids are widely used for facilitating agricultural activities, however, welfare issues are common.

Objectives

To assess working equids across three communities in Mexico, identify predominant welfare problems and document how these problems vary across locations and associated working roles and species type.

Study design

Cross-sectional survey.

Methods

The study combined the administration of a wide-ranging questionnaire to equid handlers/owners and a welfare assessment of their animal. 120 equid owners were asked about their equid management practices, the working conditions and health status of their animal. The welfare of their equids (56 donkeys, 7 mules, 57 horses) was assessed by evaluating body condition, signs of illness or injury, and behavioural indicators.

Results

Welfare varied by species, working role, sex and location. The poorest welfare was seen in one of the two arid regions (the third location having a tropical climate). Donkeys had poorer welfare than horses, and equids used for packing had poorer welfare than those used for riding and agroforestry. Overall poor body condition and wounds were the most common problems seen.

Main limitations

Work type, species type and location strongly co-varied, thus the impact of each factor could not be assessed in isolation. The sample size was relatively small.

Conclusions

Results showed significant regional variations in welfare, suggesting that environmental and/or cultural variations are producing a major effect on welfare.

Published online ahead of print.

The microhardness of the enamel, primary dentine and regular secondary dentine of seven donkey and six horse incisors was determined with a Knoop indenter at the subocclusal and mid-tooth level. The mean microhardnesses of the donkey incisor enamel, primary dentine and secondary dentine were 264·6 63·00 and 53·6 Knoop Hardness Number, respectively. There was no significant difference between the microhardness of the enamel and primary dentine on the incisors of the donkeys and horses, but the microhardness of the regular secondary dentine of the donkeys' incisors at the mid-tooth level was slightly but significantly less than that of the horses. There was also a difference in the microhardness of the secondary dentine between the subocclusal and mid-tooth levels in both donkey and horse incisors.

Because most donkeys live well beyond 30 years of age (Crane 1997), it has been proposed that their teeth may be harder than the teeth of horses, wear more slowly, and thus remain functional for longer (Misk and Seilem 1999). There have been studies of dental microhardness in human beings (Craig and Peyton 1958, Collys and others 1992), sheep (Suckling 1979), cattle (Attin and others 1997) and horses (Muylle and others 1999b). In horses, there are differences between breeds in the rate of dental wear caused by attrition (Muylle and others 1997, 1998) and in the microhardness of enamel and secondary dentine (Muylle and others 1999b), which could account for these differences. It is proposed that there may be a similar difference between the microhardness of the teeth of donkeys and horses that may contribute to the less rapid attrition of donkey teeth.

The aim of this study was to compare the microhardness of the enamel and primary and secondary dentine of the incisor teeth of donkeys and horses, to determine whether there was a significant difference between them.

Normal dental anatomy and the range of dental disorders found in donkeys are largely similar to those described in horses. Recent studies have shown dental disease to have a high prevalence in donkeys. Some dental disorders, such as diastemata, displaced teeth and wave mouth can have serious clinical consequences by causing oral pain and weight loss and even predispose to colic. Many of these signs can be prevented by regular dental treatment that can slow down or even prevent the progression of these disorders.

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.