Happy New Year: A round up of all of the parasites we have seen this year

We’ve been lucky enough to see quite a range of parasites at Ridgeway this year, including some new ones and some that we’ve encountered many times. We thought we would share a few of these with you to sum up some of our work this year. We look forward to seeing what new and exciting species 2021 brings us!

Dictyocaulus filaria

A new parasite for us this year, the sheep lungworm Dicytocaulus filaria was an interesting worm to source and study. This lungworm has a direct lifecycle, meaning it does not require an intermediate host or vector to transmit the parasite. Sheep excrete D. filaria onto pasture. There, it then develops into infective larvae ready to infect any sheep that encounter it whilst grazing. D. filaria causes a harsh, dry cough and lives in the bronchi of the lungs. If you’re concerned about a dry, harsh cough in any sheep that have we can provide a prompt testing service. Alternatively, we also culture the parasite for research purposes so if you would like to purchase click here.

For more Information on types of lungworm, visit our articles on sheep, cats and dogs and cattle.

Raillietina cesticillus

Raillietina cesticillus is a returning parasite for us this year, with many encounters in the past as it is a fairly common worm found in poultry. R. cesticillus is a tapeworm or cestode and, similarly to other tapeworms, is elongated and  segmented. This particular species can be up to 15cm long, with a large number of segments that are wider than their length. R. cesticillus has an indirect life cycle withbeetles as the intermediate host of. At Ridgeway, we have used the flour beetle, Tribolium castaneum to successfully complete the life cycle. Generally, most free-range chickens have a low and asymptomatic infection. Treatments for R. cesticillus include administration of fenbendazole as a wormer. If you are concerned that your animals have tapeworm, you can make use of our testing service.

Davainea proglottina

Whilst working with R. cesticillus this year, we discovered Davainea proglottina in the mix. It is also a poultry tapeworm. Similar to R. cesticillus, D. proglottina has an intermediate host but instead of a beetle, it is a slug. The common field slug or grey slug (Agr. reticulatus) and the garden slug (Arion hortensis) are the usual intermediate hosts, and are widely prevalent in the UK. This tapeworm is commonly much smaller than R. cesticillus, only about 0.5-2mm in length and appears distinctly different. D. proglottina only has around 4-9 segments which appear bulbous. This tapeworm is known to be much more pathogenic than R. cesticillus. If you’d like to send us a sample for testing find out more here.

Capillaria obsignata

Capillaria is also a common poultry parasite, usually only present in free-range birds. High C. obsignata burdens can cause emaciation, diarrhoea, and listlessness, but is treatable with anthelmintics (wormers). Capillaria species can have direct and indirect lifecycles, with C. obsignata being the former. This means infection can spread throughout any environment where birds are present, independent of an intermediate host. As a result, this worm can be hard to eradicate. For more information on Capillaria species, please see the article we posted earlier this year.  We provide a Capillaria testing service at ridgeway, so if you’d like to send us a sample for testing find out more here.

Turkey Coccidiosis: Eimeria meleagrimitis, adenoides, gallopavonis, meleagridis

Coccidiosis is caused by the protozoan parasites Eimeria or Isospora. There are many different genera and species that can infect a wide variety of mammals, birds, reptiles and fish. Typically, Eimeria or Isospora parasites are host specific so cannot infect other host species. This year we have worked a lot with the Eimeria that infects turkeys, with species including  E. meleagrimitis, E. adenoides, E. gallopavonis, E. meleagridis, E. dispersa. We have also worked a lot with chicken Eimeria in the past.

Coccidiosis can be a severe and even fatal disease that spreads rapidly, as it has a short incubation time of about 4-7 days from ingestion to subsequent onset of disease. Typically the disease consists of a severe infection in the gut causing enteritis. Different species of coccidia can infect different parts of the gut, leading to slightly different signs. Signs to look out for consist of lack of response, lethargy, ruffled feathers, hunched appearance, diarrhoea, bloody faeces, and antisocial behaviour. Coccidia survive very well in the environment and so it is very hard to contain an outbreak without the use of coccidiostats and vaccines. It is important to remain vigilant and contact your vet as soon as you suspect this, as it can be fatal and wipe out or reduce the productivity of entire flocks of birds.

To get your animals tested for presence of Eimeria and other coccidian species, see our services page. To read more about Eimeria and coccidiosis, check out the article we wrote previously.

Culture Parasites

We hope you’ve found these parasites as interesting as we have! In addition to these, we have also worked with a lot of our culture parasites this year, including rumen fluke (Calicophoron daubneyi), liver fluke (Fasciola hepatica), small intestinal roundworms (Cooperia oncophora), the barbers pole worm (Haemonchus contortus), the brown stomach worm (Teladorsagia circumcincta), Large roundworm of pig (Ascaris suum) and the Medium/Brown stomach worm (Ostertagia ostertagi).

If you would like to purchase any of these parasites, click here or if you require your animals tested as you suspect infection with any of these parasites, please look at our testing services.


Flynn’s Parasites of Laboratory Animals. (2008). Germany: Wiley.

Abdou, A. (1956). Journal of Helminthology, 30(4), 189-202.