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Advanced Veterinary Advice
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VETERINARY ADVICE FOR ALPACA OWNERS These notes were written and provided for publication by kind permission of Gina Bromage. From a meeting convened by Gian Lorenzo D’Alterio. Grateful thanks are due to many colleagues who contributed, and to Martyn Jose. Handling Facilities Solid-sided yards are best, because there is no possibility of animals getting their limbs trapped in the fencing. Catch pens should be small enough for animals to be caught quickly and easily. A yard layout which allows animals to be held post-treatment near to the ones remaining to be treated, is useful to stop those waiting panicking because the herd has left them alone. Technique Animals should not be held waiting for treatment for very long periods, and should be left in their normal groups, not mixed with ‘strangers’ while waiting. Often they will retain dung and urine while waiting and we had two very sad tales of problems which can occur. In one, an alpaca retained urine while waiting a long time to be shorn, then tried to escape and got stuck over a fence. This resulted in a ruptured bladder, and the animal died the next day despite surgery to try to save it. On another occasion, an animal became so stressed by waiting for treatment that it entered a state of nervous exhaustion and could not move, eat or drink. It took a week of intravenous fluids and intensive nursing to save it. It’s common for animals to retain urine and faeces during transport, so it must be ensured that they are not left in trailers for long periods. (e.g. Overnight before being taken to a show). If journeys are unavoidably long (i.e. more than about four hours) then some dung should be carried in the vehicle in a bin liner, so it can be put down on the floor to provide encouragement for the animals to urinate and defecate in the trailer or a yard. Regular handling to condition score and to reduce fear is very beneficial. Where long courses of injections have to be given, the sub-cutaneous route should be used if possible, since it is less painful. A small amount of injection for the sub-cutaneous route going into muscle should not prove a problem apart from hurting the animal at the time. To avoid abscesses, it’s important to avoid injecting a wet skin, and use an area when a tent of skin can easily be raised, so the needle stays in it and doesn’t either go straight out the other side, or straight through into the muscle. Draw back to make sure you are in the right place, and use at least a new needle for each animal and a new one kept in the vaccine pack, or a new sterile syringe-plus-needle for each dose, so that you won’t contaminate the vaccine in the pack with bacteria from alpaca skin (or anywhere else). Don’t be tempted to keep packs which have been opened; they are not expensive enough to be worth the risk. It’s probably not worth using Covexin instead of Heptavac (or preferably Lambivac) because it doesn’t come in small enough pack sizes and has the problem of too many different vaccines in one. (See later.) The latest shearing date in a pregnant female was thought to be about 10 - 10 1/2 months, although reports of shearing right up to uneventful births abound. It’s important to take into account the handling facilities and the individual animal; some can easily be done without stress or struggling, and others get more upset. More excitable animals should not be shorn near to their expected delivery date, because struggling could lead to twisting of the uterus, which would prevent normal delivery, and may even result in death of the mother and cria. Where it’s necessary to milk out a mother, this can be achieved more easily than by hand using an adapted syringe. This should have the injecting end cut off and the edges smoothed off, so that the open barrel can be placed over the teat and the plunger pulled back to apply suction. Cases of agalactia, where the milk dries up for no obvious reason, have been seen, but sadly we have neither explanation nor remedy at present. Preventative Medicine Vaccination Vaccination against Clostridial diseases is recommended, but there is no actual research to provide evidence that it does any good. The vaccines are not licensed in camelids, and are given in a spirit of hopefulness. Heptavac is commonly used but Martyn Jose knows personally of one case in which it failed to protect an adult female from death due to a Clostridial disease, and it’s possible that trying to get immunity to fewer different Clostridia, with Lambivac, would provide better protection. A sensible routine would be to vaccinate all late pregnant females (about a month before birth)and then to do the cria at 30 and 60 days. Pasteurella (the ‘P’ in Heptavac P) does not appear to be a problem in alpaca, and the ‘P’ fraction could even be harmful, so it’s recommended not to use this. Unused vaccine, used syringes and needles should all be legally disposed of in the official sharps and doops containers which can be purchased from the Vet, and then returned to the practice when full. Parasites Camelids do get worms, basically the same ones that sheep suffer from. It’s likely that the juveniles are most at risk of disease, and these should have egg counts performed on dung samples 2-3 times over the summer. It’s important that the sample is tested for liver fluke eggs as well, because although they only occasionally get liver fluke (flukes depend on the presence of a particular snail to transmit the infestation) the test for it can also show up worms which won’t be detected on the normal worm egg test. It’s possible that affected animals won’t show diarrhoea unless about to die, because they seem to cope well with the damage caused until it’s almost too late. Some worms can multiply very quickly and the sick animal will hardly even have time to get thin. Treatment There are three types of worm which don’t respond to the ‘mectin’ injectable and pour-on medicines, and for which Panacur has to be used. (They are tapeworms, Trichuris and Capillaria.) Otherwise Ivomec, Dectomax or Eprinex are probably effective, but again, there is no licence for these in camelids, and most Vets give them at 1ml/25kg body weight (twice the cattle dose). This is because when the level of drug in the bloodstream was measured in camelids, it was found to be much lower than expected from the cattle dose. If animals were found to be infested in the summer, giving Dectomax in the Autumn/Winter should help to prevent problems in the Spring from dormant worms still in the animal. It’s worth remembering that avermectins can cause delayed dispersal of dung pats because of their effect on dung beetles. Levamisole (e.g. Nilverm) has been linked to odd behaviour after dosing and could be dangerous: It’s known to have a low margin of safety in other species, and is not recommended. If you have the grazing, consider resting fields and moving to clean pasture after treatment in the middle of the summer, when larval numbers on the ground start to rise, because it is the number of infective larvae that are being taken in by the grazing animal which determines how heavy the infestation is. The rise in larval numbers at any particular time is weather dependent, and the Ministry produces worm and fluke forecasts in the Spring and Summer to inform us. Clean pasture is any on which no stock apart from horses have grazed in that season, although if there is a very mild winter pasture may fail to go ‘clean’, because it’s the frost which kills the larvae from last Summer. If liver fluke are diagnosed, (usually a problem on permanently boggy ground) Fasinex can be used to treat them. Coccidiosis (a single-celled gut parasite) has been reported in cria and treated with Midicel. Vecoxan may be safe but it has caused diarrhoea in sheep and goats. If any evidence of Coccidia is seen on faecal samples, the advice is to treat because this a potentially fatal diarrhoeal disease. Nutrition REGULAR CONDITION SCORING IS ESSENTIAL Supplementation In general, concentrate feeds are regarded as being over used in camelids. Their digestive systems are set up for fibrous forage such as grass, hay, and chopped straw. Concentrate feeds can lead to soft faeces and obesity. In cattle, we know that high levels of concentrate feeds are associated with ulcers. We all like to see our animals in good ‘condition’ but camelids are not animals which are meant to be fat, like cats or pigs. The ideal condition score is in the range 2.5 to 3.5 on the 5 point system, or 4-6 on the 10 point system, i.e. half way between emaciated and fat. Having said that, it’s important to take into account what you are asking your alpaca to do for you: A female who is growing one cria inside her, feeding a second with milk and growing fibre is working much harder than a bachelor male or wether who is only growing fibre. It’s also normal for the condition to change to some extent over the course of the year. One particular danger from concentrate feed is gorging by a newly-calved female who suddenly has a lot more space in her tummy and an appetite to go with it. This can cause fatal acidosis. New mothers should have concentrate restricted for 48 hours post birth and be given almost entirely fibrous feeds to allow their digestive systems to adjust gradually. In imported animals in particular there may be long-standing liver damage from previous infestations of Laminella worms. These are common in heavy burdens in South America, and cause a lot of liver damage, although they seem to be eliminated during the quarantine process, and have not been diagnosed here. Once very scarred, a liver may not ever recover fully, and the liver is responsible for processing the nutrients in feed, so concentrate feeds make it work harder. Pelleted feeds are useful to tempt animals into yards for handling and monitoring, and as a vehicle for any necessary mineral supplements. Ideally we should be weighing animals regularly, but if that’s not possible monthly condition scoring to detect loss of weight early is essential. Condition scores should be taken over the loins and down the sides of the ribs. Often weight loss is an indication of an underlying problem rather than simple lack of nourishment. Copper There have been cases of severe anemia associated with very low copper levels. Anaemic animals sit about a lot, fail to graze and join the herd and move as though very tired. The inside of the eyelid and vulva (it will probably be a breeding female) will be chalky-white instead of a nice healthy pink. It is possible to administer Cosecure boluses to provide slow-release copper for a whole season, or to supplement the food. Alpaca may well be ‘copper tolerant’; in other words, need abnormally high levels of copper because they are adapted to a part of the world where it is very high naturally. It is possible to have both soil and pasture tested for mineral levels but the situation is complicated by some minerals interfering with the uptake of others, so that it is the combination which is important. In growing cria, copper deficiency can look rather like rickets in terms of symptoms. Zinc Deficiencies of Zinc have also been reported, and are also probably regional, as with copper, and may complicate, or even cause skin disease if severe. Vitamin D Late-born cria who are trying to grow fast in Winter when the light levels are low, are susceptible to rickets, caused by a lack of Vitamin D. Usually they are given a Vitamin ADE combination injection at two and six months of age. The Aussies use this a lot, and call it ‘liquid sunshine’. When it occurs, rickets causes the late-born cria to spend time lying by itself, reluctant to move, often bunny hopping when it does. It is bright and alert, and eating, but growth will have slowed. Vitamin D levels are hard to measure, but phosphate levels will be low in the blood. Treatment is with Vitamin ADE injection and Foston is probably helpful too. Vitamin E/Selenium This has been seen in areas which are naturally low in Selenium, for example Exmoor. (Vitamin E and Selenium work together, so the deficiency problems tend to be seen where both are low.) Affected cria ‘wobble’ and usually a single treatment with injections of Vitamin ADE and Selenium cure the problem. Iodine Alpaca don’t need very much of this but deficiency can still occur if there is none in the concentrate. Animals fail to thrive and respond to oral dosing with Iodine. The problem can be seen with copper deficiency and impure rock salt is a good source to remedy it. (It’s made from sea water which has high levels of iodine and also copper. Some alpaca enjoy fruit and vegetable peelings. Potatoes are not recommended, and large pieces should be cut up to avoid choking by greedy animals. Plant poisons Bracken - We would expect this to be poisonous especially when growing, but don’t know how susceptible alpaca are. Symptoms associated with liver disease and bleeding would be expected. Yew, rhododendron, laurel and spindle are poisonous. Bryonies may be poisonous. Water dropwort rhizomes are poisonous. Buttercups may cause blistering around the mouth and lips but probably wouldn’t be eaten in enough quantity to cause internal damage. Ragwort - also causes liver damage. Acorns - these are poisonous in some other species, but there are no reports that we know of alpaca suffering problems. Caution as to how many they can get to is advised. FERTILITY It’s possible to get very good fertility with paddock mating and having the male run with the females after birth. Hand mating allows for a bit (sometimes not a lot!) more accuracy with predicted delivery dates and is essential if you don’t own your own stud. Ultrasound can be used to confirm pregnancy once a male has been spat off 2-3 times, at around 30 days post mating. Difficult births can be followed by uterine infections. These can be treated with local antibiotic vaginal washes and injected antibiotic courses. Sometimes there will also be an ovarian cyst, and these have been treated with prostaglandins - Estrumate is though slightly safer at 1ml per dose. Where the cyst is follicular, Receptal has been used to induce ovulation in 24-48 hours. Some infections can cause abortion but none have been identified here yet. It’s also possible for embryos to reabsorb, and we usually don’t manage to explain why when it does happen. There is discussion over the existence of persistent hymen in maiden females. Martyn Jose advises checking for this prior to mating, especially if the stud may be a little timid, to avoid injuring him, but some Vets think that a tough hymen may be linked to congenital deformities, and that breeding from these animals may increase an already high level of these. We don’t know of any research, which indicates that this is either likely or unlikely.
SKIN DISEASE Appears to be very common, and in almost all cases mites (Chorioptes) are found, although not every animal with mites also has skin disease. The theory is that some individuals become allergic to the presence of the mite, and then get the classical hair loss, crusting, thickening and scaling of the skin, usually starting on the head and ears and spreading to the groins, armpits, legs, under tail, and sometimes to the topline as well. Many animals don’t appear to itch, but some do. The most successful site for sampling for mites is between the toes. Treatment A variety of chemicals have been used, with inconsistent levels of success and/or problems. It’s likely that eradication of the mite is needed, so that even successful treatment must be followed by effective biosecurtiy to prevent the mite getting back into the herd. Eprinex Pour On. (Ivomec and Dectomax injectable have also been used but with little long-term benefit.) Gian Lorenzo is trialling this drug at present and thinks it will be needed at weekly intervals until all the mites are gone to be effective long term. OP dips/spray chambers. Success is claimed for these but there are obvious environmental concerns with these agents. The same technique has been used with permethrin used as a pressure spray. Fipronil (Frontline). This has also been effective and should be, because the mite is a surface feeder, but is expensive to use on a herd basis. Spot On (Cypermethrin). This has also been used with success but a varying degree of adverse reactions, ranging from apparent collapse and colic, to severe agitation. These may all be signs of intense local irritation. Use in warm weather on recently-sheared animals may be associated with the reaction. Taktic (a pig mange remedy) wash is being tried by one member, but we have no results yet. Long term (1 month) antibiotics. These help to combat the secondary infection of the damaged skin, and Gian Lorenzo recommends 1/3-1/2 sachet (high dose) of Uniprim powder in food daily for a month. Bathing. Some special shampoos, eg Malaseb, or Vet Plus Coatex, can help the skin to recover, but depend on the weather being warm enough. |
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