NEWSLETTER N°62
HEDGEHOG NEWSLETTER - NUMBER 62
Please let me have any tips, comments, ideas, problems or information that I can pass on to other hedgehog rehabilitators by way of this newsletter. If you are anywhere other than in the UK please remember this newsletter is about the European Hedgehog and that drugs and legal implications may be different in other countries. I am continuing my notes on some of the parasites found on hedgehogs. MITES Some of the mites stay on the surface of the skin so can be seen quite easily if they are in large numbers. However some will burrow and some seem to do both. To identify the mites that can be seen on the surface of the hedgehog it is best to use a microscope. They are quite mobile so you could catch them on a piece of sellotape and attach this to a microscope slide. Those that burrow under the skin will need a skin scraping to identify them. A positive result obviously means there are mites present but a negative result means there are no mites in that particular scraping but there could be elsewhere on the hedgehog. A typical life cycle is as follows: The eggs are laid on the host and are either attached to hair shafts or just loose in the hair. They hatch into larvae and develop into nymphs and then adults. The mite’s lifecycle can last 21-35 days on the host animal, but in some species the adults are reported to be able to survive off the host for 2-14 days. CHEYLETIELLA – these can transfer onto humans and other animals and so are zoonotic. They are visible to the naked eye. If a new admission is examined on a white formica surface these sorts of mites will sometimes fall off the hedgehog and look like small specks of dust, but they move!! These mites live on the skin surface and can survive off the hedgehog so this means they can be re-infested by direct contact with other hedgehogs AND from the environment. Signs shown besides seeing the actual mites may be dandruff, itchy skin, possibly redness or the skin and crusts. The mites are most easily seen on the face, feet and around the anus and tail. Treatments include - Johnson’s Rid Mite or Frontline plus treatment for any secondary complications. I prefer to use the milder RidMite initially. Scabs and thickened ears can be painted with Tea tree oil to both soften the scab so it lifts off and does not provide a hiding place for the mites and also to kill the mites themselves. Only use tea tree oil diluted and every other day. Treat for any secondary infections. The treatments used will mainly depend on the preferences of your veterinary surgeon. Provided it works and the hedgehog does not have any adverse reactions then the treatment has been effective. NOTOEDRES – often found in the ear. They can cause itchiness, or in severe cases disorientation and loss of balance. Treatments include Canaural, diluted tea tree oil, and diluted Ivermectin – secondary infections will also need treatment. CAPARINIA TRIPILIS – does not affect humans. Again this mite can be seen with the naked eye particularly on the face of the hedgehog, it can also burrow under the skin. Treatment as for Cheyleitiella CHORIOPTES – these can be seen on the surface of the hedgehog they do not burrow. They are usually found on farm animals rather than domestic ones. Treatment as mentioned before. With all the previously mentioned mites preventing re-infestation should simply be by avoiding contact with other hedgehogs. However do keep cages clean as some mites could fall of in the dandruff thus avoiding treatment and return to the host a few days later. TROMBICULA AUTUMNALIS (or Harvest Mite) – they can transfer onto humans. The first active stage in the lifecycle of this mite is the six-legged larva and unlike the previously mentioned mites this is the only stage that attacks animals. These larvae are present on vegetation and are active during the day, especially when it is dry and sunny. When they come into contact with any warm blooded animal they swarm on and congregate in areas where there is little hair and the skin is quite thin. This usually occurs around the end of June, but can be earlier, and persists through the summer until the end of September. The larva feeds by thrusting its small hooked fangs into the skin surface layers of the skin. It then injects a fluid that breaks down the cells underlying the horny layers of the skin. The liquid food resulting from this process is sucked back into the digestive system of the larva. It will inject and suck for two to three days at the same site until it is replete and has increased in size three to four times. The larva then drops to the ground to complete its life cycle. It descends into the soil and after about six weeks becomes an eight-legged nymph and then an adult which eats plants and small insects. Eggs laid by the adult in the spring and summer hatch into the six-legged larva known as harvest mites and the cycle starts again. Johnson's RidMite could be used, as could Frontline. Ivermectin seems to kill these mites but treatment may also be needed for secondary infections OTHER CONSIDERATIONS Healthy hedgehogs should be able to cope with a few mites. If the hedgehog is having problems then it could be that the hedgehog is not in the best of health or is elderly. It may also happen if a hedgehog is in an enclosed garden and does not have many choices of nesting places. This could mean that the nest also becomes overrun with mites and the hedgehog has no other place to go. Try to address the reason for the mites becoming a problem - this could include feeding up if it is thin, burning old bedding from its nest box regularly. If a hedgehog has a hind leg missing it may not be able to groom itself as thoroughly as is necessary. If this is the cause a regular dusting with Johnson’s RidMite may help. TREATING SECONDARY PROBLEMS – excess scratching may allow bacteria to enter wounds. The warm and protected environment inside the ear canals may also encourage bacteria to multiply. If the hedgehog is scratching its ear, holding its head to one side or becomes disorientated these are all signs that a closer inspection of the ear is required. Some mites may also carry ringworm so this may also be present and need treating. In addition mange can be very debilitating and extra care like syringe feeding eg Hills AD may be required. The following mites are usually found only when skin scrapings have been taken. As I mentioned before a negative result does not mean there are no mites present on the hedgehog. DEMODECTIC MANGE - symptoms of Demodectic mange include loss of prickles and hair, flaky and crusty skin and possibly sores. The mites tend to live in the hair follicles or sebaceous glands. The life cycle is spent entirely on the host and it only spreads by direct contact. The mites are probably always to be found on the host but tend to develop into mange when there is a drop in the host’s immunity. In domestic animals a better diet and attempts to improve the immunity are as good as active treatment in mild cases. SARCOPTIC MANGE – this is probably the cause of many cases of hair and prickle loss in hedgehogs. Often the tummy become devoid of hair and the face also shows hair loss and scabs develop. Females burrow a tunnel into the skin and lay 3 to 5 eggs daily up to around 40 to 50 eggs. Larvae hatch in 3 to 5 days. Some larvae remain in the tunnel in which they hatched, while others wander over the skin surface before burrowing. It is suggested that they are most prevalent in late winter and early spring. Treatment Regimes CHEMICAL - there are a number of different treatments. However some are very toxic both to the hedgehog and the person applying it. Baths or sprays can be used eg Amitraz, Ivermectin can be used topically ie applied to the skin or by injection. Tea tree cream and tea tree oil has also been suggested but it must be diluted and only used every other day. The tea tree oil will also help soften and remove scabs and sooth the skin. Because the sarcoptic mange mite can live off the host the living area should also be cleaned using either the treatment if it is a spray or a bath or with a suitable disinfectant. Do make sure the cage is dry with no puddles of chemicals that the hedgehogs might drink. Treatments are usually repeated several times at 7-10 day intervals. PREVENT REINFESTATION – the demodectic mange mite tends to stay with its original host so unless there is a female hedgehog with young it is unlikely to spread to other patients. A healthy hedgehog is less likely to develop problems and once in captivity a good diet. The sarcoptic mange mite can live off the host and is more mobile so could attach itself to another host. OTHER CONSIDERATIONS - It is likely that all hedgehogs have these mange mites but they only become pathogenic when the host is not fully fit. This could be an elderly hedgehog in the wild. In captivity stress seems to be a trigger and it is seen in hand reared hoglets and over-wintered hedgehogs. The hedgehog may need antibiotics to treat any secondary infections. It will also need time to grow back its prickles. Some hedgehogs can lose all their prickles and until they grow back again would be very vulnerable if released. Indeed under the Abandonment of Animals Act it would probably be illegal to release them in this condition. Sometimes the prickles take a long time to grow back and sometimes they never do. A good diet including vitamin supplements containing zinc may help. Avocado Reply 1 - it is toxic and I have seen African Grey parrots die after only eating a small amount. I am not sure how toxic it is to small mammals but feeding avocado would seem to be an unnecessary risk. Fennel for bloat in hoglets Mix 1 level teaspoon of fennel seed with 3 teaspoons of hot water. Steep. Add 1-2 drops pf liquid per 2 teaspoons of made up milk. Levamisole (wormer) I have been told this is available in liquid form (Levacide) and is used for pigeons. You may be able to get it from a pet shop, especially in areas where pigeon racing is popular, or from an Agricultural shop or show. Wildlife Treatment Regimes During the eleven years the Wildlives Rescue and Rehabilitation Centre has been open, between 350 and 400 hedgehogs have passed through the doors each year. At Wildlives every life counts, and every death is not only saddening but carefully discussed and examined to see if anything can be learnt from it. As a result of this policy an ever-increasing proportion of the patients are now being released successfully back into the wild – in recent years an unprecedented success rate of just under 80% has been achieved due to the development and refinement of the Wildlives treatment regime. Parasites are a fact of life in wild animal populations, and would be, in our opinion, impossible (and most likely unwise) to eradicate. When times are good and food is plentiful, the natural parasite burden is kept under control by the animal’s own immune system. However, in the lean times the immune system is weakened, and the balance can easily be tipped so that the parasites proliferate, and can be the cause of death even if not the cause of the original illness. In recent years post mortem examinations of hedgehogs have shown that all the hedgehogs have severely inflamed, infected, or even collapsed lungs with a very heavy worm burden – even those brought in for unrelated problems such as road traffic accidents or animal attacks. Hedgehog life has been hard due to a number of factors. The food supply has been reduced, due to prolonged drought conditions and to the destruction of habitat, with physical fitness being reduced and stress factors rising. For these little animals that are already struggling, any illness or injury could tip the balance fatally. Parasite treatment is, therefore, one of the mainstays of the Wildlives regime. There is little point in curing a broken leg or a wound for the animal to succumb to parasite activity almost immediately, and the removal of the parasites from the equation leaves more hedgehog energy for healing and recuperation. On admission, all the hedgehogs are weighed, and will continue to be weighed daily. This is necessary not only to calculate dosage of drugs, but because on occasion weight loss is the only obvious symptom of ongoing problems. Stress and dehydration rapidly become problems for a hog that is impeded by illness from its normal activity, so the hedgehog is given 10% of body weight of Hartmann’s solution subcutaneously – this is given over a period of several hours using different injection sites. The hedgehog is then examined carefully for external injuries. If any major injuries are found, the Wildlives hedgehogs are treated by a local vet, while minor wounds and abrasions are cleaned at Wildlives. Once it has been ascertained the hog is more or less in one piece, then, with a jeweller’s loupe or magnifying glass, it is checked for mite infestation. One mite is not much of a problem, but in severe cases the infestation can consist of a coating several mites deep, which is not only very stressful and unpleasant for the hog, but means that the top layers of mites are not going to be affected by any drug treatment given to the hedgehog. If such an excessive infestation is found, the hedgehog is showered. No soap is necessary – the pressure of the shower stream is used to blast the mites off down the plughole. After the shower the hedgehog will be prone to chills, so is dried as far as possible and placed under a light or on a heat pad to keep warm while it dries. Mild mite infestations do not need to be showered, as the drug regime will also kill external parasites. Hedgehogs that are cold to the touch are also given heat pads or external heat sources, until they are more active and able to sustain their own body temperature.