Creepy Crawlies and your horse

Creepy crawlies and your horse or donkey

  • Lice
Damalinia Equi (Biting lice)

Damalinia Equi (Biting lice)

Haematopinus Asini

Haematopinus Asini


Symptoms – Infestation with lice is known as ‘pediculosis’ it commonest during the winter months when the coat is long.  Lice are visible with the naked eye (see the pictures in the blog) they lay eggs on the horses coat which are commonly referred to as ‘nits’ these can be seen through a magnifying glass.

Pediculosis causes a scurfy appearance to the coat and commonly affected areas are the mane, tail and head.  There are two main types of lice, the sucking louse (Haematopinus Asini) and the biting louse (Damalinia Equi). Different treatments are necessary for the differing types of lice.  Biting lice can be treated with topical treatments, whereas sucking lice are best treated with systemic therapy (injection).

Fortunately these lice are species specific, so they won’t live on you!


Biting lice are best treated with topical treatments such as ‘Deosan Deosect’ louse powders are good for prevention of lice but rarely work as a treatment.  Topical treatments often have to be repeated two weeks later as the eggs hatch.  Sucking lice can be treated with injectable preparations or some oral wormers (although oral treatment can be unreliable).  Clipping the hair where possible is also beneficial.

  • Mites

Unlike lice these are not visible with the naked eye, although the crusts they produce can move giving the appearance of ‘walking dandruff’! They are commonly found in the feathers but can be seen all over the horse.  They cause scabs to form and affected horses are very very itchy, feather mites (Chorioptes Equi) will make horses stamp and chew their lower legs.

Treatment – This is difficult as mites in the environment are often widespread. On top of this, other horses on the yard may be harbouring mites although they show no symptoms.  Ideally all horses that are in contact should be treated.

Treatment for mites is multi-factorial, here are some tips:-

  1. Clip away excess hair – if possible clip away feathers, this will allow treatments to get good penetration down to the skin.
  2. Avoid straw – this is an abrasive bedding and can harbour mites as well. Shavings, cardboard and/or rubber matting are advised.
  3. Mite injections – An injection used for cattle and sheep to control external parasites is useful in the treatment of mites in horses.  The treatment consists of two injections three weeks apart followed by regular treatments every 3-6 months
  4. Sulphur washes – lime sulphur is an old fashioned way to treat mites but has proven to be successful when injections do not work.  It is often used in conjunction with another shampoo which removes the crusts allowing the sulphur to penetrate into the skin.  It does have a smell to it though, so not for the faint hearted, and it is worth doing a patch test as it can stain hair.

General preventative measures to avoid external parasites should also be instigated, such as, not sharing tack, regular grooming and checking your horses coat daily.

chorioptes equi

chorioptes equi