CLIPPING UP, TAKING RADIOGRAPHS, BLOOD SAMPLES and OTHER NURSING PROCEDUREs

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1 1 Clipping up, taking radiographs, blood samples and other nursing procedures Restraint The restraint of rabbits is a controversial topic with conflicting advice from vets, rescue centres, laboratory technicians, breeders and pet shops. Picking rabbits up by their ears in unanimously believed to be unacceptable. Gentle handling is very important and it should be borne in mind that rabbits are caught, held, carried and killed by predators such as foxes or birds of prey. If a rabbit is grabbed and restrained tightly, it will think it is about to be eaten and will probably try to escape by suddenly struggling and scratching. Conversely, part of the social behaviour of rabbits is to snuggle up to closely to a companion and remain in close proximity, so if it is restrained gently it will probably keep still. Pinning a rabbit down by restraining it across the shoulders can easily cause a spinal fracture or dislocation if the rabbit tries to leap so it is better to place a hand on either side of the rabbit, rather than across the shoulders. Wrapping the rabbit in a towel is a good alternative. Immobility response Many rabbits will become quiet, relaxed and immobile if they are gently and calmly placed in dorsal recumbency. If they are maintained in this position, most rabbits enter a trance like state characterized by lack of spontaneous movement and failure to respond to external stimuli. During this trance like state, there is hypotonia of flexor and extensor musculature, abolition of the righting reflex, depression of spinal reflexes, miosis, and a drop in blood pressure, heart rate and respiratory rate. An awareness of external stimuli is maintained and there is a decreased response to noise and painful stimuli. This response is often described as hypnosis, the freeze response or trancing. Sudden noise or painful stimuli will interrupt the trance. There is considerable variation in individual susceptibility to this technique. It is difficult or impossible to induce it in wild rabbits or in lively pets. There is controversy about whether tranced rabbits are in a state of terror or not. The immobility response is a subject that evokes strong views with some organisations suggesting that rabbits should never be turned on their backs. Is a rabbit that is lying on its back in a state of relaxation or tonic immobility? The answer to this is that we do not know for certain. Those people that believe the rabbit is terrified often use the term TI (tonic immobility) to describe this trance-like state. Tonic immobility is a state of fear that is characterised by stiff musculature ( scared stiff ). The word tonic means the muscles are stiff rather than relaxed. There is confusion about what is meant by tonic immobility. There several definitions and descriptions of tonic immobility in the scientific literature. Many species exhibit an immobile state under certain circumstances. In humans, tonic immobility is a catatonic state of fear that occurs in rape victims or people enduring some type of serious attack. If this is what is meant by TI, it is not surprising that rabbit owners would not wish their rabbits to be so frightened, There are several descriptions of tonic immobility in rabbits on the Internet. Not all are up to the standard that is required for publication in a scientific journal. The scientific evidence about tonic immobility in rabbits is confusing. Some studies describe neurological pathways or the response to pain when tonic immobility has been induced. Others examine the parts of the brain that are stimulated. The results are confusing of these studies are confusing and conflicting. It is hard to separate the stress response of a rabbit being turned on it back from the effect of being picked up or having a needle placed in a vein to take a blood sample.

2 2 In many papers, the method of inducing tonic immobility is not described in the abstract or in the materials and methods section of the paper. How the immobility response is attained is very important. A state of terror could be present in a rabbit that is restrained in a manner that a predator, such as a fox, would use. Predators tend grab and grasp a rabbit by its skin or by an extremity such as a limb or ears, so restraining a rabbit in dorsal recumbency by gripping the scruff and holding it on its back is likely to be frightened. This is how you would have to restrain a wild rabbit or lively pet on its back because it is not easy to evoke a relaxed immobility response in these rabbits. How to induce a relaxed immobility response In docile pet rabbits, an immobility response can be induced by cradling the rabbit like a baby before slowly and gently placing it on its back. Making a shushing noise seems to help. This is not how a predator would behave with them. It is very important that the rabbit is not grabbed or restrained tightly. If the rabbit feels threatened, it is likely to struggle and try to escape. If it is handled gently, the rabbit is likely to remain calm and still before entering a relaxed trance like state. Once it is immobile, the rabbit will remain in the same position, often without restraint, unless it is stimulated by sudden noise or movement. It will recover from the experience with no sign of distress once it is turned over into a normal sitting position. Rabbits can be medicated or even fed in this position, which does not indicate a state of terror. Turning a rabbit on its back is very useful for examination of the hocks, perineum and incisors. Matted or soiled fur can be removed. Ultrasound examination on the abdominal organs can take place. Claws can be clipped and radiographs taken without the need for sedation. Clipping away soiled fur from under the tail There is no easy description of the mass of caecotrophs, with or without fur and urine that can accumulate around the anogenital region of some rabbits. It is a common syndrome Owners often describe it as 'diarrhoea' but it is really caecotrophs that have not been ingested that is causing the problem. Urinary incontinence makes matters worse. The caecal material sticks to the fur under the tail. It looks like faeces and smells strongly and unpleasantly. Effects of uneaten caecotrophs Caecotrophs contain volatile fatty acids that give them a characteristic odour and also scald the skin leading to pain and secondary dermatitis. This starts a vicious circle of painful skin reluctance to groom soiled fur superficial pyoderma painful skin. The circle needs to be broken to treat the problem. The condition is unpleasant for the owners and difficult to manage. If the cause is not identified and treated, the condition keeps recurring and, unless they are very dedicated, owners become disillusioned with their pet and deterred by the presence of the faecal mass and the constant smell. The inconvenience of constantly bathing and cleaning their rabbit's perineum often result in owners abandoning their pet or leaving it permanently confined to its hutch. Uneaten caecotrophs lead to skin infections, which attracts flies so affected rabbits are high-risk candidates for myiasis so although uneaten caecotrophs are not a directly life threatening condition, the implications for the welfare of the rabbit are far reaching. Causes of uneaten caecotrophs Dietary: High protein diet Low fibre diet Too much high calorie food Dietary change Taints from foods that alter the odour of the caecotrophs

3 3 Physical factors: Obesity is common and makes the rabbit too fat to reach around to its anus. Spondylitis and other spinal disorders that reduces flexibility so the rabbit cannot turn around and reach its anus Illness and loss of appetite for any food including caecotrophs. Interrupted daily routine. Fluffy coat No functional incisors so rabbit cannot grasp caecotrophs to ingest them Large dewlap Neurological deficits (e.g. E. cuniculi) that affect sensation or balance Rhinitis affecting sense of smell Physical deformity- missing or deformed limbs Elizabethan collars Pain associated with caecotroph ingestion Dental disease Sore perineal skin from contact with volatile fatty acids in caecotrophs stuck in matted fur Urine scalding Infected perineal skin folds Sore hocks Arthritis Treatment of uneaten caecotrophs Diagnose and, if possible, treat the underlying cause CLIP OFF THE SOILED FUR AND TREAT THE INFECTED INFLAMED SKIN. The fur has to be removed to solve the problem. Just bathing the rabbit does not work. It leaves a mass of damp soiled fur next to the skin, which can make it even more sore. A pair of sharp curved scissors is useful in addition to a set of clippers that work. Sedation if necessary if the caecotrophs are attached to skin. No matter how much care is taken during the clipping process, occasional skin wounds are unavoidable. They usually heal quickly without problems. Stitches or tissue glue may be required for large wounds. Creams can be to treat the inflamed skin although some rabbits develop a contact reaction to Sudocream and other antiseptics. Creams containing corticosteroids should only be used once on inflamed skin. They cause thinning of the skin very quickly. Dietary modification to include plenty of good quality hay or grass is required. More fibre and less calories will increase the rabbit's appetite for caecotrophs and make them firmer Weight reduction. For rabbits that are overweight, it is important that they become thinner and more flexible. Restricting their food will also make them hungrier and more likely to eat their caecotrophs.? Probiotics are often recommended in order to establish a healthy caecal microflora. Studies into their efficacy have been inconclusive. Many of the bacteria and yeasts that are present in probiotics are often not normal inhabitants of the rabbit's GI tract. However, probiotics do no harm. Long term management of uneaten caecotrophs Some rabbits, e.g. those without functional incisors or with fluffy coats, will struggle to eat their caecotrophs when they are moulting and there is a lot of matted fur covering their anus. Others, mostly those with spinal deformities, will never manage to ingest their caecotrophs from their anus although they may turn round and eat them out of the bedding.

4 4 Really disabled rabbits will need cleaning on a regular basis. These rabbits need long term management and dedicated owners. If possible, the owners can be taught to clip the fur from around the tail and genitalia each week. Initially, it may need to be done by a vet or a vet nurse so the owner can see the normal anatomy Radiography Many conditions may be diagnosed by abdominal radiography e.g. kidneys stones, aortic calcification, gastric dilation, neoplasia, gut stasis, spondylosis or other spinal deformities, pregnancy etc. Abdominal radiography can easily be performed without sedation, although skull and chest radiography is more difficult without chemical restraint as perfect positioning is required. To take a conscious lateral abdominal radiograph, the rabbit should be picked up gently, without scruffing, and quietly positioned on the cassette. A long sandbag over the neck and a towel over its head are all that is needed to restrain it as most rabbits quickly go into a trance and lie still. Switching off the lights, moving slowly and making a quiet shushing noise can also help to keep the rabbit calm. Loud noises, sudden movements, firm restraint or leg ties are counterproductive as they stimulate the rabbit to move and try to escape. The immobility response can be used to take ventrodorsal views. Collecting blood samples The choice of site for blood collection is a matter of personal preference. Each site has advantages and disadvantages. The ease of blood collection is affected by the degree of vasodilation, the size and nature of the rabbit and its blood pressure. Vasodilation is also affected by medications, such as medetomidine. Increased body temperature dilates the vessels whereas cold temperatures constrict them. Marginal ear vein The major advantage of this site is its accessibility and the minimal restraint that is required. The rabbit is placed on a table and may be restrained by wrapping it in a towel. The marginal ear vein is easily identified after clipping away a small amount of fur. In large rabbits or in those with good blood pressure and dilated veins, sufficient blood is easy to collect. However, if the rabbit is small or has low blood pressure or vasoconstriction, it can be very difficult to collect sufficient blood before it clots in the needle. Central auricular artery Like the marginal ear vein, the central auricular artery is easily accessible. It is usually very easy to collect sufficient blood quickly, even in small rabbits. Some texts describe a risk of necrosis of the pinna after blood collection from the auricular artery. This is unlikely but a large haematoma can form easily. A single puncture is made using a small needle (>23g) and firm digital pressure is applied to the puncture site is required as soon as the needle is withdrawn. This may need to be maintained for a few minutes to prevent haematoma formation. Jugular vein As in other species, the jugular vein is a good site for collecting sufficient blood without the risk of clotting or haemolysis. The blood flows freely and blood can be collected from ill rabbits with low blood pressure or those that have been anaesthetised. However, it can be difficult to locate and visualise the jugular vein beneath the dense fur. Some rabbits have a large dewlap that obscures the vein. The method of restrain is important. The neck needs to be extended with the head tilted slightly backwards

5 5 Cephalic vein The cephalic vein is a popular choice because it is a familiar site for venous access in other species. In rabbits, the cephalic vein is small but can be seen easily through the thin skin once the fur has been clipped away. Raising the vein can be awkward because of the short front legs especially in small rabbits. Saphenous vein The saphenous vein in rabbits is large and easily visualised through the skin once the fur has been clipped away. This is a useful site for blood collection although restraint is not as straightforward as it is for blood collection from ear vessels. The saphenous vein is bigger than the cephalic vein and large enough for blood to flow freely, even in small rabbits.