Alpacas are becoming very popular on lifestyle blocks around the Waikato. Alpacas are members of the South American camelid family, the same family as llamas, but an alpaca [70 to 90 kg] is smaller than a llama [100 to 200 kg]. Their original habitat was the unforgiving mountainous regions of the Andes. Alpacas are prized for their fibre, which is stronger and more resilient than merino sheep wool.
Alpacas are generally hardy animals, but like most domestic animals may be susceptible to some conditions.
· Clostridial diseases affect most domesticated animals, with diseases such as enterotoxaemia, botulism, tetanus, blackleg and malignant oedema. Fortunately vaccination gives good protection.
· Few clostridial infections have been reported in alpacas but use of a clostridial vaccine is advised. There are no vaccines [or medicines and worm drenches for that matter] specifically developed for alpacas in this country, so any useage is off label. However their efficacy in other domestic animals is high in preventing disease, and so they are being routinely used in alpacas.
· In the absence of any other information, I would recommend vaccination of pregnant dams at least 2 months prior to due date of giving birth, followed by a booster shot 3 to 4 weeks later.
· The immune system of the cria lacks maturity and may not respond to vaccination at an early age, however it may be prudent to vaccinate in the first month of life and again a month later and at weaning.
· This disease is widespread in farm animals but has so far not been reported in alpacas.
· A family of organisms seen worldwide, that cause diseases such as TB and Johnes disease that usually develop slowly.
· There are only rare reports of natural cases of TB in alpacas in South America, so they do not appear to be particularly susceptible.
· TB testing of Alpacas is not compulsory in NZ, since neither alpacas nor their by-products are consumed. However, the Alpaca Association requires animals going to shows, be Tb tested within 2 months of going to a show, or come from a herd where a regular testing programme is in place. Animals going to a stud for mating may also be required to be tested.
· Johnes Disease is widespread in sheep, cattle, goats and deer in NZ, and usually presents as a syndrome of a non-responsive chronic diarrhoea and weight loss, usually in older animals. It has been reported in Australia in alpacas, and it is probably only a matter of time until it is reported in this country.
· Alpacas have been found to be relatively resistant to internal parasites. However, NZ farms are widely contaminated with infective larvae from other grazing animals, which makes it more likely that alpacas will become infested.
· The contamination of the pasture is related to stocking density, and worm infestation is much more likely where alpacas are grazed with other livestock.
· Alpacas have communal dung piles, which tend to help limit the spread of worms, and these piles can be removed regularly by shovel.
· All the common anthelmintics used on other classes of livestock are likely to be effective.
· FE is caused by a fungal toxin that flourishes in pasture litter, in late summer early autumn, when the weather is warm and moist, under ideal climatic conditions the toxic spores produced by the fungus can increase rapidly.
· The fungal spores are ingested and the toxin sporidesmin is released. This toxin is responsible for damage to liver cells, leading to the build up of photodynamic toxins in the blood, which are ultimately responsible for the clinical signs of photosensitivity that are seen.
· Clinical signs are those of irritation, restlessness, skin swelling, crusting and oozing, death in acute cases, decreased body condition or growth rates in more chronic forms.
· Unfortunately alpacas are one of the most highly susceptible species to FE, more so than sheep, cattle and deer, and the most common clinical sign is sudden death.
· Diagnosis is by clinical signs, blood test or post mortem.
· There is no treatment, the liver damage is permanent, although remaining liver cells may increase in size to help overcome the deficit in liver function.
· Prevention is the best way.
1. Monitor spores by spore counting during danger periods. Remembering the spore levels deemed to be safe for other classes of stock are probably not safe for alpacas. Long term consumption of low levels of spores may be just as damaging as short term high levels.
2. Fungicide spraying of the pasture is effective in killing the fungus, but not the spores, and can give protection for up to 8 weeks depending on the product used and application rates.
3. Remove animals from toxic pasture and feed supplementary feed during the danger period.
4. Zinc salts are effective in reducing liver damage by interfering with the enzyme pathway that produces the damage. Alpacas are not big consumers of water, so treatment of troughs with zinc sulphate is ineffective, plus the zinc sulphate is not very palatable. Zinc oxide can be provided in capsule form [Time Capsules] to sheep and cattle but the coating appears to be rapidly broken down by alpacas so it is ineffective. Zinc oxide can therefore be drenched every 3 to 4 days or more easily the zinc oxide can be added to the feed with molasses to disguise the taste.
Rye Grass Staggers
· A nervous condition that is caused by an endophyte in the stalk of rye grass in summer.
· Clinical signs are stumbling, shaking, unsteadiness and falling.
· The condition is rarely fatal in itself but can result in traumatic injuries to affected animals.
· There is no cure apart from prompt removal from rye grass pasture, and supplementary feeding. Hay made from rye grass is safe as the endophyte is destroyed by the drying process.
· Usually only affects younger animals under 2 years of age, although an animal once affected by rye grass staggers will always be susceptible to it.
· NZ pastures are traditionally high in rye grass, but this is not a recommended feed for alpacas as it is relatively high in protein, which can affect the coarseness of the fleece.