By Dr Marjori Orr
Ill-thrift
If your goats are not doing well, there are many possible causes. The obvious ones are under-feeding and worms, but if you rule these out, what’s left? Here are some of the possibilities - selenium deficiency, iodine deficiency and Johne’s disease.
Mineral deficiencies
Goats are just as susceptible to selenium deficiency as sheep, but probably more susceptible to iodine deficiency and less susceptible to cobalt deficiency.
Selenium deficiency
- If does are deficient in selenium and/or vitamin E, their kids may be born with heart muscle damage that can cause stillbirths or weak kids or sudden death in newborn kids.
- As they get older, kids with selenium deficiency don’t grow well and they may be stiff and reluctant to move because of skeletal muscle damage.
- This is white muscle disease.
- If the soil on your farm is deficient in selenium, it can be added to fertiliser and top-dressed onto pasture.
- It can also be added to anthelmintic drenches or a long-acting selenium injection can be given.
Iodine deficiency
- In iodine deficient inland areas, goitre can occur in newborn kids whose mothers’ diets have not been supplemented with iodine while pregnant.
- Goitre is a swelling of the thyroid glands at the top of the neck just below the throat.
- Iodine deficiency can be induced in goats or in their foetuses by feeding brassicas and clovers. These contain chemicals (goitrogens) that reduce thyroid hormones.
- In older kids iodine deficiency takes another form – myxoedema.
- This is an odd condition in which the kids’ growth is stunted, their skin is thickened and they look “podgy”.
- To prevent the disease, does can be dosed with potassium iodide at intervals of 3 to 6 months or they can be given a long-acting iodine injection.
- In lower-risk areas, providing iodised salt licks may be sufficient.
Johne’s disease
- Johne’s disease is an infectious incurable disease of ruminants including goats.
- It causes diarrhoea and weight loss in young goats from 1 to 3 years of age.
- Over a period of weeks or months and in spite of any treatments you give, the disease progresses and the goats die. It’s incurable.
- Fortunately there is a vaccine that can be given to very young kids to help prevent the disease.
- If you suspect Johne’s disease in your goats, get a vet to check it out and discuss vaccination and management changes to help prevent further cases.
Miscellaneous diseases
Ruminal acidosis
- Like other ruminants goats need time to adapt to energy-rich feed.
- If they suddenly gorge on grain or concentrates they are in big trouble!
- The microbes in their rumen will not be able to cope and the result is a build up of acid in the rumen, severe indigestion and possibly even death.
- Mild cases can respond to dosing with milk of magnesia (15ml) repeated every few hours.
- Goats need to be introduced to grain slowly over a period of a few weeks.
- After shearing, Angora goats are virtually naked until the coat regrows sufficiently to provide some insulation, and this can take weeks.
- In the meantime they are very susceptible to cold stress in wet windy weather particularly if they are not well fed.
- A rumen full of food particularly roughage produces heat as it is digested and this helps keep the animal warm.
- Signs of hypothermia are dullness, back arched, head down, back to the wind, then eventually recumbency and death.
- This condition, characterised by a soft spongy swelling along the belly (ventral oedema), has been recognised in New Zealand in Angora goats of South African and Texan origin and also in their crossbred offspring.
- It occurs mainly in young goats just after shearing, when as many as 15% of the flock can be affected.
- Affected goats are usually bright and alert and most recover spontaneously within a few days.
- In some cases there is no apparent predisposing cause although cold stress seems to be a factor.
Bottle jaw
- “Bottle jaw” is a fluid swelling under the jaw between the mandibles. Sometimes it extends to the brisket.
- This is usually the result of a disturbance of fluid distribution in the body because of low concentrations of the protein albumin in the blood.
- The causes include protein loss caused by intestinal worms or Johne’s disease.
Tetanus
- Tetanus occurs occasionally in goats.
- The clostridial bacteria that cause it can enter the body through a site of injury, e.g. caused by ear-tagging, castration, disbudding or a penetrating wound.
- Clostridial vaccination is effective in preventing tetanus.
Urinary calculi
- In wethers, especially if they were castrated young, gravelly stones can form in the urine and they can cause painful and sometimes fatal blocks in the urine flow through the penis.
- Feeding grain and concentrates for any length of time seems to be an important predisposing factor.
- If the blockage is at the very tip of the penis in the small worm-like appendage that goats have there, the problem is sometimes fixed by cutting this off using sterile instruments.
- Failing this, veterinary help is needed.
Poisons on the farm
Accidental poisoning of livestock is not common, but it still occurs regularly.
The signs are many and various, but the most common signs of poisoning are:
- Diarrhoea
- Vomiting
- Unusual excitement - or unusual dullness
- Body tremors
- Pain (teeth-grinding, reluctance to move, arched back)
- Convulsions
Common garden plant poisons:
- Rhododendron
- Yew
- Laburnum
- Delphinium
- Blue lupin (a fungal toxin in lupins can cause lupinosis)
- Iceland poppy
- Cestrum
- Oleander
- St John’s wort
- Avocardo
Native trees and shrubs
- Tutu
- Ngaio
Pasture weeds
- Ragwort (goats are more resistant to ragwort poisoning than cattle or horses but their liver can be damaged if they eat enough of it).
- Foxglove
- Goat’s rue
Chemical poisons
- Accidental overdosing with selenium can cause poisoning.
- Superphosphate poisoning can occur when livestock are put onto top-dressed pasture before the fertiliser has been washed into the soil.
- 1080 poisoning can cause deaths in livestock that are allowed onto poisoned land, and deaths have occurred after accidental drops of poisoned bait onto pasture.
- Lead poisoning can occur from licking lead acid batteries or old sump oil.
- Organophosphates (overdosing with insecticide or anthelmintic).
To prevent poisoning
- Don’t throw garden prunings into the paddock and remember that some garden plants are more palatable when wilted.
- Fence off rubbish dumps and check native scrub for tutu and ngaio before allowing livestock access to it.
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