March 22, 2009

Angora (Mohair) Goat Basics: Diseases PART 2 (skin & brain)

Agriculture, animal husbandry, animal health, diseases, goats, Angora, Mohair, skin, brain

By Dr Marjorie Orr



Skin lesions – overview

The signs of skin disease are usually fairly obvious, with itchiness, or hair loss, or scurfiiness or sores, or reddening or some other change in the appearance of the skin. Sometimes though the long hair of Angora goats can hide developing disease, giving you a nasty surprise at shearing time! As with all diseases it pays to be vigilant to spot the early signs of disease, and this means hands-on inspection, not just eye appraisal.

Here are some of the most common types of skin problem in Angora goats.

Lice
  • There are several types of external parasite (ectoparasite) that can cause skin itchiness and hair loss in Angoras, but by far the most common of these are lice (Damalinia species and Linognathus species).
  • Lousy goats have a scurfy skin and they are constantly itchy so they rub up against posts and fences and have a scruffy appearance.
  • To confirm that your goats have lice, part the fleece in various places and look for ‘moving dandruff’ as the lice scuttle out of sight.
  • There are several effective louse powders and pour-on treatments available.

Flystrike
  • Goats are not as susceptible to flystrike as sheep, but they can certainly be ‘struck’, and goats that are not healthy for any reason seem most at risk.
  • Flystrike tends to occur under dirty wet fleece particularly along the back or around the tail.
  • It’s most common in late summer and autumn in humid mild conditions.
  • You’ll need to be very observant to spot the early signs of eggs on the wool or skin or small sores containing maggots.
  • Affected goats are restless, they seek shade, twitch their tail, swing round to try to nibble affected areas and stamp their feet.
  • The maggots can be removed with meths (a horrible job) and the sore can be treated with flystrike powder available from your veterinarian or rural supplier.
  • Insect repellent on the surrounding wool will help keep the blowflies away.
  • In severe cases, euthanasia may be the only humane option.

To prevent flystrike
  • remove the attraction of dirty smelly fleece by keeping your goats dagged and clean. o Treat any cuts and sores and keep an eye on them until they’ve healed.
  • Flytraps can help attract blowflies away from stock. If enough flytraps are used early in the season, they help prevent flystrike.
  • Apply long-acting pour-on or spray-on insecticide treatments but note that following treatment there is a withholding time before the fleece can be sold.

Dermatophilosis
  • Dermatophilosis, sometimes called mycotic dermatitis, can produce quite extensive skin lesions in Angoras, with scurfiness and hair loss along the back, particularly after prolonged wet weather.
  • In kids kept in damp dirty conditions it is a common cause of scurfy scabby skin over the muzzle and it can look similar to scabby mouth. It can affect the lower legs too.
  • Providing a dry clean environment and good feeding and shelter usually results in spontaneous recovery, otherwise antibiotic treatment from your vet will be effective.

Scabby mouth
  • Scabby mouth (also called orf or contagious ecthyma) is a viral infection that is most common on lambs, but it can affect kids too.
  • It causes crusty sores, usually around the lips and muzzle.
  • Lesions usually heal spontaneously, but antibiotic cream and in severe cases antibiotic treatment from your vet will hasten recovery.
  • Grazing thistles often makes it worse,
  • It's a disease that can be transferred to humans.

Brain disease – overview
Fortunately brain disease isn’t common, but when it does occur it’s very serious.

Listeriosis or circling disease
Circling is the main sign of this disease in sheep but in goats the most common signs are:
  • Dullness
  • Head held high and to one side
  • Ear drooping
  • Paralysis of the jaw
  • Drooping of the eyelids
  • The disease is most common in adult goats in winter because it’s associated with feeding hay or silage of poor quality.
  • The obvious prevention is to ensure only good quality hay and silage are offered.
  • Treatment means antibiotic injections from your vet, but this is often unsuccessful.

Polioencephalomalacia

Polioencephalomalacia or PE is associated with a sudden change in feeding and it occurs in goats from 2 months to 3 years old. Sudden grain feeding can upset the balance of microbes in the rumen.

The result is a thiamine deficiency that damages part of the brain and the signs of this are:
  • Aimless wandering
  • Blindness
  • Teeth grinding
  • Straining the head up and back
  • Muscle rigidity
Consult your vet immediately if you see the signs because treatment requires thiamine by injection and it may not be effective unless given very early.

Meningitis
  • Meningitis means inflammation of the membranes over the brain, and this can result in fever, dullness, convulsions and sometimes death.
  • It is often caused by infection spreading from some other site in the body.
  • Veterinary treatment with antibiotics can help in early cases but it’s not usually successful.
Disbudding can be a cause of meningitis if it’s done badly. Fortunately very few Angora goat kids are disbudded, but there have been reports too of over-zealous disbudding of kids causing trauma and heat damage to the brain, leading to meningitis and death.

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