Strongyles - Donkey - Revision history

Lizhazellsmith at 12:03, 21 November 2016

2016-11-21T12:03:04Z

Lizhazellsmith at 10:27, 14 October 2016

2016-10-14T10:27:27Z

Lizhazellsmith at 10:26, 14 October 2016

2016-10-14T10:26:55Z

Lizhazellsmith at 12:03, 11 February 2015

2015-02-11T12:03:47Z

Lizhazellsmith at 12:01, 11 February 2015

2015-02-11T12:01:59Z

Lizhazellsmith at 11:52, 11 February 2015

2015-02-11T11:52:58Z

Lizhazellsmith at 11:44, 11 February 2015

2015-02-11T11:44:12Z

Lizhazellsmith at 11:31, 11 February 2015

2015-02-11T11:31:08Z

Bara at 21:06, 23 October 2010

2010-10-23T21:06:58Z

Bara at 22:18, 22 March 2010

2010-03-22T22:18:10Z

← Older revision		Revision as of 12:03, 21 November 2016
Line 1:		Line 1:
	==Introduction==		==Introduction==
−
−
−	~~===Large strongyles===~~
−	~~[[Image:Large strongyles donkey.jpg\|right\|thumb\|250px\|<small><center>Large strongyles (Image courtesy of [http://drupal.thedonkeysanctuary.org.uk The Donkey Sanctuary])</center></small>]]~~
−	The common large strongyle species infecting equids are ''Strongylus vulgaris, S.edentatus and S. equinus''. Similar species are observed in horses and donkeys. A new species, ''Strongylus asini'', has been seen in donkeys and other wild equids. ''Triodontophorus spp''., some ''Craterostomum spp''., and ''Oesophagodontus robustus'' are also in this group.
−	* ''S. vulgaris'' are pathogenic due to damage caused by vascular migration
−	* A study in Zimbabwe has shown that the intensities of infection of adults in the large intestine and larvae in the cranial mesenteric artery and its branches were much higher than those recorded in horses (Pandey and Eysker, 1989)
−	* ''S. edentatus'' migrates through the liver and peritoneum, causing associated damage
−
−	Similar pathogenic effects of ''S. vulgaris'' in donkeys to those found in horses have been reported. In donkeys, various lesion types have been recorded. These include minimal arterial lesions, small thrombi and substantial thrombi, the size of a tennis ball, where the arterial wall is greatly thickened, corrugated, gritty and full of larvae. These arterial lesions, which can interfere with the blood supply to major parts of the alimentary tract, may be one of the major contributory factors for the weakness, low productivity and early demise of working donkeys.

	===Small strongyles – Cyathostomins===		===Small strongyles – Cyathostomins===

← Older revision		Revision as of 10:27, 14 October 2016
Line 1:		Line 1:
	==Introduction==		==Introduction==

		+
		+	===Large strongyles===
		+	[[Image:Large strongyles donkey.jpg\|right\|thumb\|250px\|<small><center>Large strongyles (Image courtesy of [http://drupal.thedonkeysanctuary.org.uk The Donkey Sanctuary])</center></small>]]
		+	The common large strongyle species infecting equids are ''Strongylus vulgaris, S.edentatus and S. equinus''. Similar species are observed in horses and donkeys. A new species, ''Strongylus asini'', has been seen in donkeys and other wild equids. ''Triodontophorus spp''., some ''Craterostomum spp''., and ''Oesophagodontus robustus'' are also in this group.
		+	* ''S. vulgaris'' are pathogenic due to damage caused by vascular migration
		+	* A study in Zimbabwe has shown that the intensities of infection of adults in the large intestine and larvae in the cranial mesenteric artery and its branches were much higher than those recorded in horses (Pandey and Eysker, 1989)
		+	* ''S. edentatus'' migrates through the liver and peritoneum, causing associated damage
		+
		+	Similar pathogenic effects of ''S. vulgaris'' in donkeys to those found in horses have been reported. In donkeys, various lesion types have been recorded. These include minimal arterial lesions, small thrombi and substantial thrombi, the size of a tennis ball, where the arterial wall is greatly thickened, corrugated, gritty and full of larvae. These arterial lesions, which can interfere with the blood supply to major parts of the alimentary tract, may be one of the major contributory factors for the weakness, low productivity and early demise of working donkeys.

	===Small strongyles – Cyathostomins===		===Small strongyles – Cyathostomins===

← Older revision		Revision as of 10:26, 14 October 2016
Line 1:		Line 1:
	==Introduction==		==Introduction==

−	~~===Large strongyles===~~
−	~~[[Image:Large strongyles donkey.jpg\|right\|thumb\|250px\|<small><center>Large strongyles (Image courtesy of [http://drupal.thedonkeysanctuary.org.uk The Donkey Sanctuary])</center></small>]]~~
−	The common large strongyle species infecting equids are ''Strongylus vulgaris, S.edentatus and S. equinus''. Similar species are observed in horses and donkeys. A new species, ''Strongylus asini'', has been seen in donkeys and other wild equids. ''Triodontophorus spp''., some ''Craterostomum spp''., and ''Oesophagodontus robustus'' are also in this group.
−	* ''S. vulgaris'' are pathogenic due to damage caused by vascular migration
−	* A study in Zimbabwe has shown that the intensities of infection of adults in the large intestine and larvae in the cranial mesenteric artery and its branches were much higher than those recorded in horses (Pandey and Eysker, 1989)
−	* ''S. edentatus'' migrates through the liver and peritoneum, causing associated damage
−
−	Similar pathogenic effects of ''S. vulgaris'' in donkeys to those found in horses have been reported. In donkeys, various lesion types have been recorded. These include minimal arterial lesions, small thrombi and substantial thrombi, the size of a tennis ball, where the arterial wall is greatly thickened, corrugated, gritty and full of larvae. These arterial lesions, which can interfere with the blood supply to major parts of the alimentary tract, may be one of the major contributory factors for the weakness, low productivity and early demise of working donkeys.

	===Small strongyles – Cyathostomins===		===Small strongyles – Cyathostomins===

@@ Line 121: / Line 121: @@
 ==References==
 * Lichtenfels, J.R., Kharchenko, V.A., Krecek, R.C., and Gibbons, L.M. (1998). ‘An annotated checklist by genus and species of 93 species level names for 51 recognised species of small strongyles (Nematoda: Strongyloidea: Cyathostominea) of horses, asses and zebras of the world’. ''Vet. Parasitol''., 79. pp 65-79.
 * Pandey, V.S., Eysker, M. (1989). ‘''Strongylus vulgaris'' in donkeys (Equus asinus) from the highveld of Zimbabwe’. ''Vet. Parasitol'. 32. pp 173-179.
 * Rose, R.J., Hodgson, D.R. (2000). ''Manual of Equine Practice''. W.B Saunders, Pennsylvania, USA.
 * Trawford, A.F., Morriss, C.J., Bell, N.J., and Reid, S.W.J. (2001). ‘Comparing the Efficacy of Moxidectin with Ivermectin in the Donkey’. Paper presented at: The 18th International Conference of the World Association for the Advancement of Veterinary Parasitology. 26-30 August. Stressa, Italy.

@@ Line 92: / Line 92: @@
 # To preserve drugs for the future
 It is claimed that 99% of worms occur on the pasture, whereas 1% occur in the horse (Rose et al, 2000). This statement is equally applicable to the donkey and so no worm control programme should depend solely on drugs. It should also include good pasture and stable management:
-* Good stable hygiene
+* Good pasture hygiene
-* Rotational grazing, proper pasture management and harrowing pastures is most important
+* Rotational grazing, proper pasture management and harrowing pastures (when weather conditions are optimal) is most important
 * The use of a ‘biological vacuum’ (sheep<sup>3</sup> ) is still pertinent to ingest larvae on the pasture and is used on [http://wwww.thedonkeysanctuary.org.uk/ the Donkey Sanctuary’s] land both in winter and early spring.
-* Removal of dung at least twice a week in the summer is carried out mechanically
+* Removal of dung at least twice a week either manually or mechanically significantly reduces pasture contamination (Corbett et al)
-* If donkeys are at pasture in the winter months then faecal sampling may need to be carried out throughout the year
+* Faecal sampling should be conducted at least four times a year
-* Grazing pasture should be rested at least five months of the year (the estimated survival time of cyathostomins)
+* If donkeys are at pasture in the winter months then faecal sampling may need to be carried out throughout the year depending upon weather conditions
-* Managing young stock, which has lower worm larva immunity, on separate pastures from older groups
+* Grazing pasture should be rested for as much of the year as possible
 <sup>3</sup> The use of sheep may increase the incidence of the stomach worm ''Trichostrongylus axei'', but the pathogenecity of this species in donkeys is rarely a problem.
-Application of the above principles can be applied to donkeys in most cases. Owners should always be advised to consult their veterinary surgeon regarding periodicity of faecal sampling/worming with regard to their own specific circumstances.
+The above principles can be applied to donkeys in most cases. Owners should always be advised to consult their veterinary surgeon regarding periodicity of faecal sampling/worming with regard to their own specific circumstances.
-Under tropical weather conditions in most developing countries, the dry season is not favourable for the development and survival of the freeliving and parasitic stages and so there is relatively little danger of acquiring infection at this time of year. Generally, animals have a high probability of acquiring infection from pasture during and immediately following wet seasons. Treating donkeys at the beginning and end of the rainy season therefore seems to be sufficient under such climatic conditions. This is usually practised in Ethiopia and other developing countries where the farmers cannot afford frequent treatment for their animals.
+Under tropical weather conditions in most developing countries, the dry season is not favourable for the development and survival of the free living and parasitic stages and so there is relatively little danger of acquiring infection at this time of year. Generally, animals have a high probability of acquiring infection from pasture during and immediately following wet seasons. Treating donkeys at the beginning and end of the rainy season therefore seems to be sufficient under such climatic conditions. This is usually practised in Ethiopia and other developing countries where the farmers cannot afford frequent treatment for their animals.
 The efficacy of worming strategies in any country should be carefully monitored by laboratory analysis and condition scoring. An epidemiological assessment of weight loss or anaemia should complement any monitoring process to determine the impact of dental disease and/or poor nutrition.

@@ Line 74: / Line 74: @@
 Elderly and immuno-compromised animals should be treated with caution, ensuring any supportive treatments necessary are given prophylactically prior to or at the time of deworming. Treatment may need to be delayed in extremely unwell animals and should be given at a time when observation post-treatment is possible.
 [http://www.thedonkeysanctuary.org.uk/ The Donkey Sanctuary] recommends a different faecal sampling and treatment programme for pregnant jennies and youngstock. More details are available on request.
 ===Control===
-The [[Anthelmintic Drugs|anthelmintic]] control programme which has been operating at [http://drupal.thedonkeysanctuary.org.uk/ The Donkey Sanctuary] for many years now has been devised so that it fulfils the following criteria:
+The [[Anthelmintic Drugs|anthelmintic]] control programme operating at [http://www.thedonkeysanctuary.org.uk/ The Donkey Sanctuary] is reviewed regularly to ensure that:
-* it is effective in controlling [[Helminths|helminths]]
+* it is effective in controlling pasture contamination
 * it reduces the incidence of cyathostomosis
 * it slows down the development of [[Anthelmintic Resistance|resistance to anthelmintics]]
 * it is cost-effective. The reduced cost of [[Anthelmintic Drugs|anthelmintics]] has offset the increased laboratory costs.
-At [http://drupal.thedonkeysanctuary.org.uk/ The Donkey Sanctuary] no donkey is given [[Anthelmintic Drugs|anthelmintic]] unless it has a positive egg count above 200 epg. Although this effectively means regularly examining the faeces of all the donkeys, it has several beneficial effects:
+At [http://www.thedonkeysanctuary.org.uk/ The Donkey Sanctuary] no donkey is given an [[Anthelmintic Drugs|anthelmintic]] unless it is deemed necessary by a clinician taking into account the animal’s history and recent FECs. Clinical cases presenting with cyathostomosis are treated with anthelmintics regardless of faecal egg count results.
-# To reduce handling and stress to the donkey when the whole herd is wormed
+This programme means regularly examining the faeces of all the donkeys, as opposed to administering treatment to the whole herd. Benefits include:
 # To reduce exposure of adult worms to repeated doses of [[Anthelmintic Drugs|anthelmintic]] and therefore development of [[Anthelmintic Resistance|resistance]]
-# To help create a ‘refuge’ of susceptible larvae on the pasture to compete with resistant strains
+# To help create a ‘refugia’ of susceptible larvae on the pasture to compete with resistant strains

@@ Line 68: / Line 68: @@
 ==Treatment==
-[[Anthelmintic Drugs|Anthelmintics]] used prophylactically and to treat acute and chronic worm infections can be categorised into four main groups as shown below.
+[[Anthelmintic Drugs|Anthelmintics]] should not be used prophylactically. Blanket treatment with anthelmintics over the last few decades has increased cyathostomin resistance to anthelmintics.
-[[Macrocyclic Lactones|'''Ivermectin''']] can effectively control adult and migrating larvae of large strongyles. As a result, colic due to thrombo-emboli caused by ''S.vulgaris'' in the vasculature of the caecum and ventral colon and damage by other large strongyle larval migration are less common in the UK. The threat from helminths has shifted away from large strongyles to small strongyles, the cyathostomins.
+[http://www.thedonkeysanctuary.org.uk/ The Donkey Sanctuary] uses drugs from all four classes of dewormer to treat clinical cases of suspected cyathostomosis. It is imperative that faecal worm egg count reduction tests are performed on at least a proportion of each group treated to ensure efficacy of treatment. Supportive treatment for [[Hyperlipaemia - Donkey|hyperlipaemia]] may also be needed, in the form of prednisolone to suppress an inflammatory response and resulting inappetance.
-In any donkey population treated with [[Macrocyclic Lactones|ivermectin]] it is possible to eradicate large strongyles if it is given on a regular basis for long enough and combined with pasture management. Cyathostomins are more difficult and require secondary measures, as do certain other endoparasites, including [[Threadworm - Donkey|''Strongyloides westeri'']], or [[Ascarids - Donkey|''Parascaris equorum'']] in foals, and tapeworms.
+Elderly and immuno-compromised animals should be treated with caution, ensuring any supportive treatments necessary are given prophylactically prior to or at the time of deworming. Treatment may need to be delayed in extremely unwell animals and should be given at a time when observation post-treatment is possible.
+[http://www.thedonkeysanctuary.org.uk/ The Donkey Sanctuary] recommends a different faecal sampling and treatment programme for pregnant jennies and youngstock. More details are available on request.
 <big>'''[[Endoparasiticides - Donkey|Anthelmintic drugs used in the donkey]]'''</big>
@@ Line 98: / Line 97: @@
 * Good stable hygiene
 * Rotational grazing, proper pasture management and harrowing pastures is most important
-* The use of a ‘biological vacuum’ (sheep<sup>3</sup> ) is still pertinent to ingest larvae on the pasture and is used on [http://drupal.thedonkeysanctuary.org.uk/ the Donkey Sanctuary’s] land both in winter and early spring.
+* The use of a ‘biological vacuum’ (sheep<sup>3</sup> ) is still pertinent to ingest larvae on the pasture and is used on [http://wwww.thedonkeysanctuary.org.uk/ the Donkey Sanctuary’s] land both in winter and early spring.
 * Removal of dung at least twice a week in the summer is carried out mechanically
 * If donkeys are at pasture in the winter months then faecal sampling may need to be carried out throughout the year

@@ Line 12: / Line 12: @@
 ===Small strongyles – Cyathostomins===
 [[Image:Cyathostomins donkey.jpg|right|thumb|250px|<small><center>Cyathostomins (Image courtesy of [http://drupal.thedonkeysanctuary.org.uk The Donkey Sanctuary])</center></small>]][[Image:Small strongyles donkey.jpg|right|thumb|250px|<small><center>Small strongyles (Image courtesy of [http://drupal.thedonkeysanctuary.org.uk The Donkey Sanctuary])</center></small>]]
-Cyathostomins were formerly called trichonemes or cyathostomes. Adult worms live in the large intestine and have a non-migratory life cycle. Infections with these nematodes typically include very large populations and numerous species. Over 50 species of cyathostomins have been recorded in horses, donkeys and zebras (Lichtenfels et al, 1998). The species of cyathostomins described in donkeys are similar to those described in horses, but ten species were found to be specific to donkeys and zebras.
+Cyathostomins were formerly called trichonemes or cyathostomes. Adult worms live in the large intestine and have a non-migratory life cycle. Infections with these nematodes typically involve very large populations and numerous species. Over 50 species of cyathostomins have been recorded in horses, donkeys and zebras (Lichtenfels et al, 1998). The species of cyathostomins described in donkeys are similar to those described in horses, but ten species were found to be specific or more prevalent in donkeys and zebras.
-Until recently, the more obvious lesions caused by ''Strongylus vulgaris'', as well as the frequent finding of large burdens of cyathostomins in apparently healthy animals, resulted in a perception that cyathostomins were not pathogenic. After a marked decrease in the prevalence of ''S. vulgaris'' in particular, there has been an increasing number of reports of serious
+After a marked decrease in the prevalence of the large strongyle S. vulgaris following the release of macrocyclic lactones at the end of the last century, there has been an increasing number of reports of serious intestinal diseases attributed to cyathostomins in horses. They are now considered one of the major causes of colic in equines in most regions of the developed world.
 The main features of this group are as follows:
@@ Line 28: / Line 27: @@
 '''Acute verminous enteritis (larval cyathostomosis)'''
-This occurs in late winter or early spring as larvae emerge in large numbers simultaneously.
+This occurs in late winter or early spring as larvae emerge in large numbers simultaneously otherwise known as ‘mass emergence’.
 ==Diagnosis==
-The objective of a worm control programme is to prevent signs of helminthosis, the clinical disease associated with helminths. Diagnosis of helminthosis can be based on:
+===History===
-===History===
+* Known to be grazing contaminated land
 ===Clinical signs===
 [[Image:Small strongyles 2 donkey.jpg|right|thumb|250px|<small><center>Small strongyles on a petri dish (Image courtesy of [http://drupal.thedonkeysanctuary.org.uk The Donkey Sanctuary])</center></small>]]
-* Diarrhoea
+There is often an absence of clinical signs accompanying low-medium grade cyathostomosis in donkeys and mules, the mechanisms for which are not fully understood. Concurrent illness or donkeys suffering immuno-compromisation may become symptomatic in which case the following clinical signs may be seen:
-* Colic
+* Digestive upset/colic
 * Ill thrift
 * Weight loss
-'''Acute verminous enteritis (larval cyathostomosis)'''
+'''Acute verminous enteritis (larval cyathostomosis or mass emergence)'''
 * Initially symptoms of abdominal pain, anorexia and depression are presented and [[Hyperlipaemia - Donkey|hyperlipaemia]] quickly follows
 * Severe inflammation with sub-mucosal oedema and haemorrhage in the caecum and colon may result in severe diarrhoea but, in the donkey, death due to ‘toxic shock’ may occur before diarrhoea develops
@@ Line 58: / Line 60: @@
 ===Laboratory tests===
 * '''Faecal examination''' for eggs or larvae
-Identification of the eggs in the faeces does not, however, indicate the presence of a clinical disease, and only when large numbers of eggs per gram (epg) have been identified can the possibility of clinical disease be considered. Conversely, as the disease may be caused by the larval stages of the parasites (as is the case with cyathostomins), then the epg may be within normal limits whilst resultant disease is present.
+Identification of eggs in the faeces does not indicate the presence of a clinical disease, and only when large numbers of eggs per gram (epg) have been identified can the possibility of clinical disease be considered. Conversely, as the disease may be caused by the larval stages of the parasites, then the epg may be within normal limits whilst resultant disease is present.
 * '''Haematology''': red blood cell count, serum protein level
-Both forms of '''acute verminous enteritis (larval cyathostomosis)''' may be difficult to diagnose ''ante-mortem'' from faeces, as the donkeys affected are often on [[Anthelmintic Drugs|anthelmintics]], which will control egg-shedding by adult worms. The parasite may also still be in its prepatent period. Less than 1% of donkeys at [http://drupal.thedonkeysanctuary.org.uk/ The Donkey Sanctuary] have evidence of encysted larvae at ''post-mortem''.
+Both forms of '''acute verminous enteritis (larval cyathostomosis)''' may be difficult to diagnose ''ante-mortem'' from faeces, as the donkeys affected are often on [[Anthelmintic Drugs|anthelmintics]], which will control egg-shedding by adult worms. The parasite may also still be in its prepatent period. At ''post-mortem'' the mucosa of the caecum and colon is congested with gross oedema of the sub-mucosa. Ruptured cysts are numerous.
 ==Treatment==

← Older revision		Revision as of 21:06, 23 October 2010
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	The efficacy of worming strategies in any country should be carefully monitored by laboratory analysis and condition scoring. An epidemiological assessment of weight loss or anaemia should complement any monitoring process to determine the impact of dental disease and/or poor nutrition.		The efficacy of worming strategies in any country should be carefully monitored by laboratory analysis and condition scoring. An epidemiological assessment of weight loss or anaemia should complement any monitoring process to determine the impact of dental disease and/or poor nutrition.
		+
		+	==Literature Search==
		+	[[File:CABI logo.jpg\|left\|90px]]
		+
		+
		+	Use these links to find recent scientific publications via CAB Abstracts (log in required unless accessing from a subscribing organisation).
		+	<br><br><br>
		+	[http://www.cabdirect.org/search.html?q=%28title%3A%28strongyl%29+OR+title%3A%28cyathostom%29%29+AND+%28od%3A%28donkeys%29+OR+title%3A%28donkey%29+OR+ab%3A%28donkey%29%29 Strongyles in donkeys publications]

	==References==		==References==

@@ Line 1: / Line 1: @@
 ==Introduction==
@@ Line 135: / Line 134: @@
 [[Category:Donkey]]
 [[Category:Parasites_-_Donkey]]