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===Small strongyles – Cyathostomins===
===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>]]
[[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.
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.
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:
The main features of this group are as follows:
'''Acute verminous enteritis (larval cyathostomosis)'''
'''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==
==Diagnosis==
===History===
* Known to be grazing contaminated land
* Previous high egg counts or lack of egg output followed by ‘spikes’ in output
* No known parasitology history
* High stocking density
* Poor pasture hygiene
===Clinical signs===
===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>]]
[[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>]]
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
* Ill thrift
* Weight loss
* 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
* 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
* 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
===Laboratory tests===
===Laboratory tests===
* '''Faecal examination''' for eggs or larvae
* '''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
* '''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.
At ''post-mortem'' the mucosa of the caecum and colon is congested with gross oedema of the sub-mucosa. Ruptured cysts are numerous.
==Treatment==
==Treatment==