United Kingdom

Common helminth infections of donkeys and their control in temperate regions

Citation

Jacqui. B. Matthews, Faith A. Burden. March 2013. Common helminth infections of donkeys and their control in temperate regions. Equine Veterinary Education.

Authors
Publication details
Publication date: 
18 March 2013
DOI number: 
doi: 10.1111/eve.12018
Abstract

Roundworms and flatworms that affect donkeys can cause disease. All common helminth parasites that affect horses also infect donkeys, so animals that co-graze can act as a source of infection for either species. Of the gastrointestinal nematodes, those belonging to the cyathostomin (small strongyle) group are the most problematic in UK donkeys. Most grazing animals are exposed to these parasites and some animals will be infected all of their lives. Control is threatened by anthelmintic resistance: resistance to all 3 available anthelmintic classes has now been recorded in UK donkeys. The lungworm, Dictyocaulus arnfieldi, is also problematical, particularly when donkeys co-graze with horses. Mature horses are not permissive hosts to the full life cycle of this parasite, but develop clinical signs on infection. In contrast, donkeys are permissive hosts without displaying overt clinical
signs and act as a source of infection to co-grazing horses. Donkeys are also susceptible to the fluke, Fasciola hepatica. This flatworm can be transmitted, via snails and the environment, from ruminants. As with cyathostomins, anthelmintic resistance is increasing in fluke populations in the UK. A number of the anthelmintic products available for horses do not have a licence for use in donkeys, and this complicates the design of parasite control programmes. As no new equine anthelmintic classes appear to be near market, it is important that the efficacy of currently effective drugs is maintained. It is important that strategies are used that attempt to preserve anthelmintic efficacy. These strategies should be based on the concept that the proportion of worms in a population not exposed to anthelmintic at each treatment act as a source of ‘refugia’. The latter is an important factor in the rate at which resistance develops. Thus, it is imperative that parasite control programmes take into account the need to balance therapy to control helminth-associated disease with the requirement to preserve anthelmintic effectiveness.

Online references

Dietary management to improve the gastrointestinal health of the donkey

Citation

Faith A. Burden, Nikki Stradling. Dietary management to improve the gastrointestinal health of the donkey. Presented at 6th European Equine Health and Nutrition Congress. (1 March - 2 March 2013). Ghent, Belgium.

Authors
Presentation details
Date presented: 
Friday 1 March 2013
Abstract

The Donkey Sanctuary is a welfare organisation which cares for over 2500 donkeys. Donkeys may require additional feeding due to dental disease, ill health or previous neglect. Research in 2005 highlighted that impaction colics (IC) were a significant cause of mortality in resident donkeys (50 cases, 16% of total euthanasias or deaths) and gastric ulceration (GU) was common in donkeys examined post mortem (PM) (41%). Further studies established that feeding practices were contributing to the incidence of IC and GU. Cox et al.1, (2007) demonstrated that donkeys fed concentrate rations were at an increased risk of developing IC (Odds Ratio=2.5, P<0.001). Research in to GU by Burden et al.2, (2009) showed an increased risk of donkeys developing GU when fed cereal concentrate rations (OR=2.4, P<0.001).

Feeding practices were changed from 2008 onwards; prior to this cereal-based rations were fed in meals to donkeys requiring additional feed. They were replaced with fibre-based concentrates fed ad libutum or in small meals. The incidence of GU and IC have been monitored since these changes through PM examination of all animals that die or are euthanased. Prevalence at PM of IC in 2011(5% (n=13)) was significantly lower (P<0.001) than in 2005 (16% (n=50)), univariable logistic regression analysis indicated that donkeys fed concentrate rations are no longer at a greater risk of IC (P>0.05) when compared with those not fed concentrates. Active GU was seen in 7% (n=25) of donkeys at PM in 2011 compared to 41% in 2005, Univariable logistic regression analysis indicated that donkeys fed fibre-based concentrate rations were at no greater risk of developing GU than those not fed concentrates (P>0.05). During this time period the only significant management changes made were those related to feeding; however the effect of other variables on the prevalence of GU and IC at PM warrants further investigation.

1Cox et al. 2007 BMC Vet Res. 2;3:1

2Burden et al. 2009 animal, 3, 287-293

Online references

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

Citation

Nicole du Toit, John Gallagher, Faith A. Burden, Padraic M. Dixon. May 2008. Post mortem survey of dental disorders in 349 donkeys from an aged population (2005-2006). Part 1: prevalence of specific dental disorders.. Equine Veterinary Journal. 40:3. 204 - 208.

Authors
Publication details
Publication date: 
1 May 2008
Volume: 
40
Issue: 
3
Page numbers: 
204 - 208
Abstract

Abstract

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.

Online references

Spatial cognition and perseveration by horses, donkeys and mules in a simple A-not-B detour task

Citation

Britta Osthaus, Leanne Proops, Ian Hocking, Faith A. Burden. December 2012. Spatial cognition and perseveration by horses, donkeys and mules in a simple A-not-B detour task. Animal Cognition.

Authors
Publication details
Publication date: 
28 December 2012
Journal: 
Animal Cognition
DOI number: 
DOI 10.1007/s10071-012-0589-4
Abstract

We investigated perseveration and detour behaviour in 36 equids (Equus caballus, E. asinus, E. caballus x E. asinus) and compared these data to those of a previous study on domestic dogs (Canis familiaris). The animals were required to make a detour through a gap at one end of a straight barrier in order to reach a visible target. After one, two, three or four repeats (A trials), the gap was moved to the opposite end of the barrier (B trials). We recorded initial deviations from the correct solution
path and the latency to crossing the barrier. In the A trials, mules crossed the barrier significantly faster than their parental species, the horses and donkeys. In the B trials, following the change of gap location, all species showed a reduction in performance. Both dogs and horses exhibited significant spatial perseveration, going initially to the previous gap location. Donkeys and mules, however, performed at chance level. Our results suggest that hybrid vigour in mules extends to spatial abilities.

Online references

The evaluation of African and UK bioactive plant extracts for the control of equid gastrointestinal nematodes

Citation

Laura Peachey, Gina L. Pinchbeck, Claire Scantlebury, Gebre Tefera, Mulugeta Getachew, D. Etana, Faith A. Burden, Andrew F. Trawford, Jacqui. B. Matthews, Jane Hodgkinson. The evaluation of African and UK bioactive plant extracts for the control of equid gastrointestinal nematodes. Presented at International Conference on Equine Infectious Diseases IX. (21 October - 26 October 2012). Kentucky, USA.

Authors
Presentation details
Date presented: 
Tuesday 23 October 2012
Abstract

In the developed world the control of equid gastrointestinal (GI) nematodes, in particular cyathostomins, is increasingly challenging due the threat of anthelmintic resistance. In developing countries such as Ethiopia despite high parasite burdens, access to genuine anthelmintic treatment is limited. In both situations there is a need for alternative treatment and management regimens for effective parasite control and consequently there has been increasing interest in the use of bioactive plant extracts (BPEs) [1]. This study identified candidate plants in the UK and Ethiopia and evaluated their in vitro efficacy against cyathostomin populations derived from donkeys. A participatory rural appraisal (PRA) approach was used to identify five ethnoveterinary medicines for use in donkeys in Ethiopia. In the UK three plants were identified following extensive review of literature citing efficacy against GI nematodes of other host species and two extracts were provided courtesy of Prof Jerzy Behnke, University of Nottingham. Hydro-alcoholic extraction of dried plant material was carried out for the eight extracts prior to reconstitution in both water and DMSO. Efficacy of each extract was evaluated by egg hatch assay (EHA) and larval migration assay (LMA) using eggs and larvae recovered from the faeces of donkeys at the Donkey Sanctuary, UK. Dose response curves were produced and ED-50 values were calculated using probit analysis. Of the five Ethiopian plant extracts tested, four showed efficacy in the EHA and/or LMA. The two most efficacious were Acacia nilotica and Rumex abyssinicus in the EHA with ED-50 values of 0.72mg/ml and 1.29mg/ml respectively. Of the five UK extracts four showed efficacy in the EHA and/or LMA. The two most efficacious were Carica papaya (papaya) in the LMA and Allium sativum (garlic) in the EHA with ED-50 values of 18.9µM and 0.65mg/ml respectively. The two BPEs most efficacious in vivo for Ethiopia and the UK are to be carried forward to in vivo trials. This study has demonstrated in vitro efficacy of nine plant extracts against cyathostomins. There is evidence in the literature that these plant extracts show efficacy both in vitro and in vivo against GI nematodes in other species. Therefore these results have identified potential alternatives to synthetic anthelmintics for the treatment of cyathostomins that require further investigation.

[1] Githiori JB, Athanasiadou S, Thamsborg SM. Use of plants in novel approaches for control of gastrointestinal helminths in livestock with emphasis on small ruminants. Vet Para 2006;139, 308–320.

Online references

Drug Resistant Cyathostomins in Donkey Herds; Lessons in Management for All Equids

Citation

Andrew F. Trawford, Faith A. Burden. Drug Resistant Cyathostomins in Donkey Herds; Lessons in Management for All Equids. Presented at International Conference on Equine Infectious Diseases IX. (21 October - 26 October 2012). Kentucky, USA.

Authors
Presentation details
Date presented: 
Sunday 23 October 2011
Abstract

The Donkey Sanctuary has over 2500 donkeys on its farms in the UK. Endoparasite control in these herds has been a major focus for the last 10 years. Monitoring of the herds has identified significant levels of anthelmintic resistance in the cyathostomins parasitising the donkey herds. Lack of efficacy of ivermectin, moxidectin, pyrantel and fenbendazole has been identified on multiple sites and in a number of cases treatment of donkeys harbouring such parasites is becoming increasingly challenging. Changes in management practices and approach to parasite treatment is discussed. Research to establish the extent of drug resistance and clinical significance of parasitism in donkeys is of primary concern; projects have focussed on identification of drug resistance, impacts of pasture management, validation of thresholds of faecal egg counts for treatment and alternatives to anthelmintics. Significant changes in management practices have been based upon results of these studies and new ideas and techniques are being developed. Treatment of all donkeys is carried out on the basis of a strongyle faecal egg count which is carried out on a 4-weekly basis throughout the year. Preliminary data and clinical experience has shown that increasing the FEC treatment threshold for healthy, mature donkeys to ≥ 1000 strongyle epg is sufficient to control clinical disease whilst reducing pasture contamination. Application of new treatment thresholds have reduced the reliance on chemical treatment. The mean number of anthelmintic treatments per year per animal was one in 2011; this is a significant reduction from previous dosing regimes where animals would be treated a minimum of four times per year. Animals are monitored frequently with problematic herds being 100% sampled every four weeks; such monitoring allows individualised treatment programmes and highlights reduced egg reappearance periods early. Reduced ERPs are investigated immediately with suspect animals undergoing a faecal egg count reduction test (FECRT) at the next treatment. Failed FECRTs trigger an alternative approach to treatment and further investigation. It is evident that some individual cases are becoming increasingly difficult to treat effectively; future trials of combinations of anthelmintics are being considered. Effective parasite control has also led to an increased emphasis on pasture management; dung is closely managed and carefully composted. Pasture is also rested in 6 month blocks with mixed species grazing instigated where possible. Good pasture management practices produce significant drops in pasture larval counts and is the primary mechanism used to reduce parasitism. Research and practical experience has emphasised the importance of good pasture management, treatment based upon faecal egg counts and routine assessment of efficacy of treatment. Researching and trialling higher dosing threshold has also led to significant decreases in the reliance of the organisation on anthelmintics with no recorded clinical effects. The lessons learnt from management of these large herds of donkeys may provide salient and important foundations for future equid herds that undoubtedly will experience similar problems in the future.

Online references

A novel approach to pain recognition in donkeys

Citation

Gabriela Olmos, Faith A. Burden. A novel approach to pain recognition in donkeys. Presented at 14th World Congress on Pain, Sattelite Symposia: Pain and Pain Management in Non-Human Species. (27 August - 31 August 2012). Milan, Italy.

Authors
Presentation details
Date presented: 
Sunday 26 August 2012
Abstract

Pain due lesions and clinical conditions is one of the main welfare concerns of the more than 42 millions donkeys that presently exist in the world. Yet, the knowledge to gauge pain in donkeys is lacking, misunderstood and/or not validated (Ashley, 2005).

Pain (yes/no/uncertain) and its severity (VAS; no pain=0 to worst pain=100mm) was assessed in 403 donkeys’ ante-mortem (ATM) and post-mortem (PTM). Also behaviours/signs (BS) and pain related lesions (PRL) were assessed ATM and PTM, respectively. Using principal component analysis the more than 53 BS and 238 PRL observed were narrowed to 58 biologically meaningful component or groups (14 BS and 44 PRL components, respectively). Components were used as risk factors in multiple regression analysis to identify which BS and/or PRL are commonly used in clinician’s (veterinary/pathologist) decision making process to determine whether a donkey ‘is’ (i.e. ATM) or ‘was’ (i.e. PTM) in pain and its severity (mild to severe). Furthermore, multiple correlations were made to understand which BS relate significantly with specific PRL and how.

A cross tabulation between pain ATM and PTM, where pain related lesions are used as a quasi-gold standard of pain assessment; identify that 2 in 10 donkeys are wrongly assumed as in NO-PAIN. Moreover, only 43% of the donkey observations are used by clinicians to make their opinion on donkey pain and its severity (i.e. 7 BS and 18 PRL components were significantly associated with pain as stated by clinicians). Yet, multiple correlations showed 20 plausible biologically meaningful relationships between BS and PRL; some currently not used by clinicians.

This methodology, previously successfully used in humans (Gregory, 2010) is novel to donkey veterinary medicine and warrants further research to consolidate findings. Nonetheless, the achieved correlation list of behaviours vs. pathologies is a significant work with valid applications in donkey pain identification and prognosis.

Ashley FH, Waterman-Pearson AE, Whay HR (2005) Behavioural assessment of pain in horses and donkeys: application to clinical practice and future studies, Equine Vet J, 37(6), 565 - 575.

Gregory NG (2010) Relationships between pathology and pain severities: a review. Animal Welfare 19, 437-448.

Online references
Syndicate content