Month: August 2018

Vomiting and diarrhoea

Vomiting and diarrhoea are very common in dogs. Both are symptoms of other conditions rather than diseases in their own right and there is a vast range of dog diseases in which diarrhoea and/or vomiting may occur. In many cases the problem may be successfully treated without ever pinpointing the actual cause. However, the information that you give your vet may be vital in deciding whether the case is serious enough to need further detailed investigations.

Diarrhoea occurs when the normal functioning of the large bowel (intestine) is disturbed. The large bowel is responsible for absorbing water from the gut and if it does not do this properly, very liquid faeces (droppings) are produced.

Vomiting occurs when stomach juices are expelled from the mouth. It is important to distinguish vomiting from regurgitation. Regurgitation only occurs after a meal and the material will have visible lumps of undigested food which are often eaten again.

The causes of both diarrhoea and vomiting include viral, bacterial or parasitic infections; changes in diet, stress or excitement, poisonous drugs or chemicals, blockages or damage to the digestive system or other body organs.

Dogs will eat anything and vomit readily as a protective mechanism to prevent toxic substances entering the body. Vomiting involves big contractions of the abdominal muscles before the stomach contents are eliminated, and your dog may salivate excessively or swallow immediately prior to doing so.

If your dog has diarrhoea it may need to go to the toilet more frequently or have accidents in the house. Occasionally, bowel movements are not more frequent but just softer than normal.

Both diarrhoea and vomiting occur as short lived (acute) conditions lasting 1-2 days which will often clear up on their own, and as long-term (chronic) problems which are usually more serious. If your dog does not appear to be in distress or be losing weight, all you may need to do is to withhold all food for a day and then give your dog small amounts of cooked fish, chicken or some other food which is easily digested. Make sure clean fresh water is available.

If vomiting or diarrhoea is continuous for more than 24 hours (despite fasting), your dog could become dangerously dehydrated and should be taken to your vet.

Contact your vet sooner for puppies (they dehydrate more quickly than adults), if there is blood in the vomit/diarrhoea or if the faeces are of a black and tarry appearance (an indication of internal bleeding).

Never treat your dog yourself with drugs from your own medicine cabinet because some human drugs may be poisonous to dogs.

Diarrhoea or vomiting will be managed by fasting (unless your dog is dehydrated, in which case it may be given fluids and essential minerals by mouth or injection). Your vet may not give antibiotics because bacterial infections are one of the rarer causes of these problems and because ‘good’ bacteria are always present in a normal gut. Therefore, antibiotics (which also kill these bacteria) could actually make the problem worse.

Your vet will ask you questions about your dog, such as:

  • Is your dog ill or depressed?
  • Has your dog eaten any unusual foods?
  • Is there anything unusual about the colour and smell of the your dog’s faeces or vomit?
  • When and how often is your dog being sick or having diarrhoea?
  • Are there other dogs in the household and have these also been affected?
  • Has your dog been hunting or scavenging left over human food?
  • Has your dog been given any medical treatment or been exposed to any potential poisons?
  • Think about these questions before going to your vet and see if you can identify any possible reason why your dog may be ill.

If the illness continues for more than a couple of days it may be necessary for your vet to carry out a range of tests to find out the cause of the problem. A small sample of your dog’s faeces will be examined for bacterial infections or parasites in the gut. Blood tests may also be taken to check for infection, kidney or liver disorders.

An x-ray may be needed to see if there is anything abnormal in the gut. Sometimes your vet will put an endoscope into your dog’s stomach and intestine to try and see the cause of the problem, and a small biopsy sample of intestine may be removed for examination.

Digestive upsets are unpleasant for you and your dog but in most cases your dog will be better within 1-2 days. If your dog is not improving after 24 hours make an appointment with your vet for further advice.

Pancreatitis

Almost all dogs will have a tummy upset at some point in their lives. In most cases this will get better over a few days without any treatment. Occasionally vomiting may be a sign of something more serious in your pet. One such disease which can cause vomiting is pancreatitis. Pancreatitis is a condition with a huge range of severity from almost no clinical signs to severe abdominal upset and even death. If you are at all worried about your pet’s health please make an appointment with your vet.

The pancreas is a small organ located close to the stomach. It has an important role in the digestion of food and produces large volumes of digestive enzymes after each meal which are released into the gut to help digest food as it leaves the stomach. These enzymes are normally stored in specialised storage granules in the pancreas until they are needed.

Quite simply, pancreatitis is inflammation of the pancreas. Once the pancreas is damaged the digestive enzymes are released from the specialised storage granules into the pancreas itself and can start the process of self digestion. If large amounts are released the enzymes can start to affect other parts of the body.

The pancreas also has a second, and completely separate function, which is to produce the hormone insulin which helps to control levels of blood sugar.

Pancreatitis is usually a disease of middle-aged dogs. Some breeds of dogs are more at risk from pancreatitis – more cases are seen in small breeds of dogs, particularly Miniature Schnauzers. Obese dogs are more at risk and diet can have impact. Bouts of disease may be set off by scavenging or stealing fatty foods.

Occasionally some dogs have structural disease in the pancreas, e.g. cysts that increase the likelihood of pancreatitis developing. Some medications can cause pancreatitis so if you are worried about your dog in anyway always remind your vet what medications your dog is taking – even if you think the vet may know already. However, in most cases no reason is found for pancreatitis to develop.

As stated above, there is a range of severity of pancreatitis in the dog which can reflect the amount of inflammation in the pancreas and also the effects on the rest of the body.

The more severe forms of pancreatitis (also termed necrotising or acute pancreatitis) can be a frightening disease with sudden onset of severe signs such as vomiting and severe abdominal pain and sometimes jaundice. Dogs with acute pancreatitis show discomfort and may adopt a ‘praying’ stance – bowing down on their front legs – as they try to relieve the pain their tummy.

Other signs include diarrhoea and fever but these signs often look just like any other tummy upset. Dogs with pancreatitis are usually very miserable and don’t want to eat. In the most severe form of the disease large amounts of enzymes released from the pancreas start to move to different parts of the body which can result in difficulty breathing and bleeding from multiple sites in the body.

The milder form of the disease (also termed chronic pancreatitis) is a grumbling form of the disease which can affect dogs for months or years. In some patients there are no outward signs of pancreatitis in these pets.

Vomiting is a very common presentation in dogs and most dogs that are vomiting get better within a few days with no specific treatment. However, if your vet is worried that your dog has a more serious condition they will want to run some blood tests from your dog and probably take some X-rays or ultrasound your dog’s abdomen.

There are some special blood tests that can be run to diagnose pancreatitis and ultrasound examination may show changes in the pancreas itself to confirm the diagnosis and to assess for structural abnormalities. Ultrasound examination of the pancreas is an advanced ultrasound technique so your vet may wish to refer your pet to a specialist.

Mild cases of pancreas may recover without any treatment over a few days. Dogs with a more severe condition will need to be admitted to a veterinary hospital. Often dogs with pancreatitis will not want to eat; this is not a problem for 48 hours, but after this period measures may be taken to ensure food intake as current evidence suggests that maintaining nutritional intake can assist with recovery.

Drugs may be given to reduce nausea and vomiting which help control clinical signs and may help with appetite. In patients with severe pancreatitis feeding tubes are placed. In cases in which feeding tubes are not appropriate then intravenous feeding may be used.

Pancreatitis is a very painful condition and pain relief is an important component of management. Pain relief in most cases necessitates the use of opioid pain relief that can only be administered in hospitalised patients.

In very severe cases dogs become extremely unwell and need to be admitted to hospital for intensive care or maybe an operation. When pancreatitis is severe there can be serious effects on other organs in the body and intensive care including blood and plasma transfusions may be required.

Most dogs with pancreatitis get better within a few days to a week. Your vet will advise you on long term care of your pet after an episode of pancreatitis, which will depend on individual cases and whether any reason for the pancreatitis was found.

It may be necessary to provide your pet with a lower fat diet following its recovery from pancreatitis. Often dogs that have had one episode will be more likely to have repeated bouts later in life and these may need to monitored more carefully.

In dogs that have been severely affected there may be long term consequences of the disease. Damage to the pancreas can result in failure of its other functions. Loss of large amounts of pancreas can mean that the dog is no longer able to produce sufficient quantities of insulin (thus becoming diabetic) or not producing enough digestive enzymes (resulting in poor digestion of food and weight loss).

Unfortunately some dogs with the severe form of pancreatitis will die despite all treatment.

If you have any concerns about our dog contact your own vet for further advice.

Oesophageal foreign bodies in dogs

Some dogs are very greedy and any dog that thinks it is under threat of having a tasty bit of food taken away from it may swallow something without chewing properly. Dogs that scavenge are at particular risk of picking up and swallowing something they should not eat. Often scavenging merely results in an upset tummy but sometimes a piece of foreign material can become lodged in the throat. This is a potentially very serious condition and if you think your pet may have something stuck in its throat you should contact your vet immediately.

Any dog can get something stuck in its oesophagus. However, the dogs most at risk are greedy dogs or dogs that like to scavenge because they have access to things that are more likely to cause problems. Small terriers also appear to be more at risk and this is partly due to their size, meaning that chop bones are a perfect fit for their oesophagus (whereas larger breed dogs may get away with swallowing the same bone).

The oesophagus is the tube that runs from the mouth to the stomach down which food, liquids and saliva pass after swallowing. It is a muscular tube and quite stretchy so that if larger objects are swallowed the oesophagus stretches out to accommodate them. However, there are a number of places along the oesophagus where the oesophagus is narrowed and larger objects may become stuck.

In dogs the most common foreign body is a piece of bone, rawhide chew or toys. The pieces of bone from chops, which may become wedged across the oesophagus, are a particular problem in smaller dogs such as West Highland White terriers. You should never allow your dog to get access to cooked bones.

Another common type of foreign body is a fish hook. Dogs may pick up and eat baited fish hooks and the hook can catch in the wall of the oesophagus. In many cases the fishing line is still attached to the hook and may be visible in the mouth. Never try to pull on line or string that your dog has swallowed but instead take your pet straight to the vet. If there is a hook embedded in the oesophagus and you pull on this the barbs may tear the oesophagus causing serious damage.

Immediately after swallowing something that has become stuck dogs are usually very distressed. They will often be gagging and retching but usually don’t produce anything except some frothy white saliva. Dogs may be very restless and may paw at their mouth. Most dogs with something stuck in their throat will not want to eat and if they do will not be able to swallow. Some make repeated gulping movements.

If the object is not completely blocking the oesophagus it may be present for several days before other signs are noticed. These dogs may still be able to swallow liquids. Regurgitation of food after eating may occur and you may notice a foul smell on your dog’s breath.

Signs of respiratory disease such as coughing may be present, and, if the oesophagus becomes torn, signs of generalised illness such as depression, high temperature and a reluctance to bend the neck (due to pain) may be seen.

Your vet will probably suspect that your dog has something stuck in its throat from what you describe of the history. In order to confirm what is there and where it is stuck your vet will want to take an X-ray of your dog. Blood samples may be taken to see if there are any effects of dehydration and intravenous fluids may be given.

Once the foreign object has been identified it can usually be removed without surgery but this can be a tricky procedure and your vet may want to send your pet to a specialist to perform the procedure.

If the foreign body has been present for sometime there may be damage to the wall of the oesophagus.

Foreign bodies can be removed from the oesophagus in a number of ways:

  • Removal from the mouth by passing a tube through the mouth and grabbing hold of the foreign body and pulling it out.
  • Pushing the object down the oesophagus into the stomach and then operating on the stomach to remove the object from there.
  • In exceptional cases the object is completely wedged and cannot be moved up or down. In these cases surgical removal from the oesophagus is the only option. Surgery is also required if there is a tear in the wall of the oesophagus. This is the most serious situation due to the high risk of infection and shock.

Following removal of the object your pet will be quite sore for several days and will need nursing care at home or in a veterinary hospital. It is likely that they will also need a variety of medication to make them more comfortable and to reduce the risk of long term damage to the oesophagus.

The biggest risk is that the wall of the oesophagus may be damaged by the foreign body or torn when it is removed. However, long term problems can also occur as the oesophagus heals.

In most cases, minor damage and inflammation of the wall of the oesophagus heals quickly. However, more severe damage and tearing of the muscle layers takes longer to heal and more scar tissue forms. Large amounts of scar tissue can create a permanently narrowed area called a stricture that is unable to stretch to allow food past when the dog swallows. This can take several months to form. Signs that a stricture has formed normally include regurgitation of food, less often liquids.

It is not possible to guarantee that your dog will never swallow anything that can become stuck in its throat. However, there are a number of wise precautions you can take.

  • Never feed your dog cooked bones and never give your dog a bone that it could potentially swallow whole.
  • Ideally, avoid rawhide chews. If you do offer them, remove them from your dog once they have chewed them down to a size at which they might swallow them.
  • Make sure that all toys are large enough that they cannot be swallowed whole and are strong enough that they cannot be chewed into pieces by your pet.
  • Watch your pet closely when out for exercise to ensure they are not scavenging along the way.

An oesophageal foreign body is a potentially very serious problem for your pet. Long term outcomes are very dependent on early treatment so if you are worried that your pet may have swallowed something that has become stuck you should immediately get advice from your vet.

If you have any concerns about your dog contact your own vet for further advice.

Food allergy

We probably all know people who are unable to eat strawberries or nuts due to an allergy but it isn’t only people who can react to their food. Whilst food allergies are not common in dogs they can be affected too. Food allergies can produce many different symptoms, some of which can be quite distressing for your pet. No allergy is pleasant, but at least with a food allergy it is usually possible to avoid the cause of the symptoms so that your pet can lead a normal life.

Most dogs will have a reaction to their food at some time in their life. Usually this is a sensitivity to a particular food type (not a true allergy) and only causes a mild tummy upset. Once you recognized the reaction, and had avoided that food in future, the problem probably went away.

An allergy is a different matter altogether. If your dog is allergic to their diet, they produce antibodies against some part of their food. Antibodies are the body’s natural defence mechanism against unwanted invaders and are usually produced to fight off bugs which may cause disease. In an allergic animal the immune system is over-reactive and produces antibodies against things which should be found in the body.

The most common allergy in dogs is to beef or wheat. Each time that food is eaten the antibodies in your dog’s body react with the food and this reaction causes the symptoms. Once antibodies have developed, the immune system is able to remember that particular food for many years and if your dog eats it again the same reaction will occur.

Food allergies can produce many symptoms and so it can be difficult for your vet to make a diagnosis without doing further tests. The most common signs of an allergy to food are itchy skin or tummy upsets. Other changes that can occur are hyperactivity, weight loss, lack of energy or even aggression.

Eliminating the offending part of the diet should resolve the symptoms but it takes a long time for the old food to be completely eliminated from your dog’s body and, as such, a new diet may have to be fed for many months before any improvement is noticed.

In the past the only way to confirm a food allergy was to change your pet’s diet to avoid feeding any proteins or carbohydrates that were present in htheir normal diet (an elimination diet). If the symptoms improved on the new diet, one meal of the old diet is fed to see if the symptoms come back. An elimination diet trial is a very long process during which strict dietary control is essential – even one stolen treat may set the investigation back to day one!

A blood test is now available which allows your vet to see if there are any antibodies in your dogs blood to common things in his diet. This test may help your vet to choose the right diet for your dog immediately so that the signs resolve more quickly.

An elimination diet is a diet containing one type of protein and one type of carbohydrate, e.g. chicken and rice. This diet is fed for a number of weeks as the sole food (all titbits and additional food must be avoided). During this time all the old diet is removed from the body. The symptoms of allergy should improve as long as the new diet is being fed.

The problem with a home-made exclusion diet is that it is unlikely to contain everything that your pet needs for a healthy life. Having identified what diets resolve the problems in your pet, your vet will try to identify a commercially produced diet that you can feed your pet for the rest of its life.

Unfortunately it is not possible to cure a dog with an allergy to food. The simplest solution is to avoid the particular protein or carbohydrate in the diet which is causing the problem. Many pet foods contain a mixture of different proteins and so choosing a new diet for your allergic pet is not easy and you should discuss it with your vet. They will be able to recommend a diet that does not contain the offending food.

The part of the diet causing the problem must be avoided for the rest of your pet’s life. It is not uncommon for animals which have been allergic to one part of their diet to go on to develop other allergies so be watchful for symptoms recurring. In rare cases there may not be a suitable commercial diet available and you may be forced to prepare home cooked diets for your pet.

For further information on allergies in your pet contact the Pet Allergy Association which is a new charity related to the British Allergy Foundation: www.allergyuk.org

Progessive retinal atrophy (PRA)

There are many causes of blindness in dogs and if you suspect that your dog’s eyesight is deteriorating you should contact your vet immediately. Some of the causes of blindness can be treated and vision can be retained. Sadly, other causes like PRA cannot be treated but your vet may be able to help you cope with living with a blind dog.

PRA (also known as generalised progressive retinal atrophy or GPRA) describes a group of inherited eye diseases of dogs. PRA leads to slowly progressive blindness over a period of months or years.

PRA has been reported in more than 100 different dog breeds, but in the UK it is most commonly seen in poodles (miniature and toy), cocker spaniels and Labrador retrievers.

The earliest sign is usually poor vision at night or in dimly lit surroundings. Affected dogs may become more cautious or nervous about going outside after dusk. Over time, vision deteriorates further until day vision also becomes affected. Affected dogs may lose peripheral vision and develop tunnel vision.

The pupils may appear dilated and increased eye shine may be evident. In some dogs cataracts may develop secondary to the PRA so that the eyes appear cloudy.

The age at which signs of PRA develop varies between breeds. Typically, PRA affects middle-aged dogs (3-8 years old) although in some cases clinical signs may not develop until later in life. In a few breeds (such as the miniature schnauzer) signs may develop earlier.

Confirmation of PRA is made by examining the back of the eye with an ophthalmoscope to look for characteristic signs of retinal degeneration. If the retina cannot be examined (e.g. if secondary cataracts are present) then a test called an ERG (electroretinogram) may be performed. Your vet can refer you to a specialist veterinary ophthalmologist for this test.

DNA tests are also available for some breeds of dog. DNA tests are particularly useful in young dogs or those which may be used for breeding because they can identify affected dogs before they develop signs of PRA. They can also identify carrier animals. Carrier dogs will not develop PRA themselves but may pass the disease on to their offspring.

Unfortunately there is currently no effective treatment for PRA and affected animals will become totally blind, usually over a period of months to years. Because of the slow progression of the disease, however, most dogs learn to adapt to their blindness and continue to lead contented lives.

As PRA is an inherited disease, affected animals should not be used for breeding.

Eye medication: how to give to your dog

Eye problems in dogs are quite common. Tears quickly wash out any treatment put in the eye so eye drops need to be given several times a day. This means you will have to learn how to give the treatment at home.

Some drops only need to be given once a day, others up to six times daily. Always follow the instructions given to you by your vet very carefully. Never give more than the recommended dose and, if at all possible, try not to miss treatments.

You will find it easier to hold your dog at a comfortable working height. Try placing your dog on a table or raised surface. If the surface is slippery, put a carpet tile or towel down so that your dog feels more secure. If your dog struggles a lot, you may need to wrap your dog in a towel or blanket to prevent them scratching you. You will need to get a friend to help you – one of you will hold the dog whilst the other steadies the head and puts the drops into the eye.

  • The person holding the dog should grip the dog’s head firmly under the chin and tilt the head upwards.
  • The other person holds the dropper bottle in one hand and opens the dog’s eye using the thumb and forefinger of the other hand.
  • Position the dropper bottle a few centimetres above the eye and squeeze gently to release the right number of drops.
  • Avoid touching the eye with the bottle spout.

Ointments and creams are slightly more difficult to apply because they are thick like toothpaste.

  • Hold the dog and open its eye as above.
  • Holding the tube of ointment above the eye, squeeze out some ointment and let it drop onto the eye to lie between the lids.
  • Detach this ‘worm’ of ointment from the tube by pulling the ointment down against the lower lid.
  • Always avoid touching the eye with the nozzle.

As long as the treatment falls on the eye somewhere it does not matter where. When your dog blinks the drug will spread all over the surface of the eye.

The eye is one of the most sensitive parts of the body and putting anything into an eye may cause discomfort. However, eye drops and ointments are designed for use in the eye and any discomfort will be slight. Your dog may blink a lot or have a ‘watery eye’ for a few moments after you have put the drops in.

On rare occasions your dog may paw at the eye(s), rub its face along the floor or the white of the eye may become red and sore. If so, stop the treatment immediately and contact your vet.

Always continue the treatment for as long as your vet recommends. Eye problems often appear to get better very quickly once treatment starts but if you stop treatment too soon the problems may come back.

Most owners get quite good at giving eye drops with a bit of practice, but if you really can’t do it yourself tell your vet. They may be able to prescribe a different drug which does not need to be given so often or which can be given by mouth instead. In some cases a nurse may be able to help you, or your dog could be admitted for a few days to be given treatment.

‘Dry eye’ (Keratoconjunctivitis sicca)

If your dog has recurrent problems with their eyes or has a sticky discharge that does not seem to go away you should contact your vet. It may be that they have a problem with tear production in the eyes. Lack of tears leads to dry eyes which are sore and often become infected or damaged. If this condition is recognised and treated early on it may be possible to control the condition and prevent permanent damage to the eyes.

Keratoconjunctivitis sicca (KCS or ‘dry eye’) develops when insufficient tears are produced from the tear glands. Tears keep the surface of the eye moist, help to flush away surface debris (such as dust landing on the cornea), provide lubrication to aid blinking, and have antibacterial properties to fight infections. Reduced tear production may affect all of these important functions. Over a period of time, affected eyes may become blind due to scarring and pigmentation of the cornea.

The most common cause in dogs is when the body’s own immune system attacks the tear glands, which are then gradually destroyed over a period of months or years. What exactly triggers this attack to make some dogs develop KCS is unknown.

Usually both eyes are affected, although sometimes to different degrees. Clinical signs include the following:

  • Conjunctivitis, which may respond to antibiotic treatment but has a tendency to recur.
  • A sticky grey discharge from the eyes (this discharge may turn white, yellow or green if it becomes infected).
  • Clouding or dullness of the cornea.
  • Discomfort around the eyes – the animal may blink more than normal or rub at its eyes.

KCS is diagnosed by performing a Schirmer tear test. This simply involves placing a strip of filter paper against the cornea and measuring the degree of wetting over the course of 1 minute. The Schirmer tear test is quick and easy to perform, and well tolerated by the patient.

Your vet will be able to give you something to help your pet if they have dry eyes. The aims of treatment are to keep the eyes comfortable and to minimise the scarring and pigmentation caused by KCS, which may lead to blindness if left untreated. Most cases of KCS will need lifelong management. Treatments will vary from case to case.

Medication to stimulate tear production

In most cases, the first-line treatment is ciclosporin 0.2% eye ointment (Optimmune™). This treats the underlying cause of KCS by reducing the immune system attack on the tear glands. For optimal results there must be some residual tear gland function, so this treatment works best in mild to moderate cases. It is usually very effective, but treatment must be given twice daily every day, and lifelong treatment is usually required. If Optimmune™ fails to work, then in some cases other similar types of drug may prove effective (for example ciclosporin 1% solution or tacrolimus).

Lubricants/ artificial tears

Various types are available. These include drops, gels and ointments to keep the surface of the eye moist and prevent evaporation of tears. These do not treat the underlying cause, but instead help to replace the tears that are not being produced. They are often used in conjunction with Optimmune™.

Antibiotics

Corneal ulcers and bacterial infections occur quite commonly in dogs affected with KCS and so a course of antibiotic eye drops may be prescribed from time to time.

Surgery

Parotid duct transposition (PDT) can be performed if the above treatment proves ineffective. This surgery involves relocating a duct of one of the salivary glands from its usual opening into the mouth to inside the lower eyelid. Saliva is then secreted onto the surface of the eye and acts to keep the surface of the eye moist.

In many cases, this proves a very effective treatment. However, saliva is not exactly the same as tears, so in a few cases it may cause problems such as irritation to the surface of the eye or to the skin around the eye. For this reason, PDT is usually reserved as a last resort should medical management fail.

Whatever treatment is recommended, lifelong management will usually be needed and regular visits to your vet will be required in order to monitor tear production and ensure that the eye is responding successfully to treatment.

Corneal ulcers – a sore eye

The basic structure of a dog’s eye is much the same as a human’s eye. Consequently dogs can suffer a similar range of eye diseases to humans. Because the eye is complicated, delicate and easily damaged, all eye problems require immediate veterinary attention.

A corneal ulcer is a hole in the clear covering of the front of the eyeball (the cornea). Sometimes only the top layer of the cornea (the epithelium) is affected but in some cases the damage may go deeper and become more difficult to treat. On rare occasions a corneal ulcer can become infected with bacteria that may produce toxins. These toxins can destroy the surrounding normal tissue, leading to a rapid deepening of the ulcer that can cause loss of the eye unless treated quickly and appropriately.

Common causes include:

  • External trauma (e.g. by a thorn or cat claw).
  • A foreign body such as a piece of grit or grass seed caught under the eyelid.
  • Eyelashes or hairs growing in the wrong place on the eyelid.
  • Inherited/ breed-related problems such as in-turning of the eyelids (entropion).
  • Some bacterial or viral infections can also cause corneal ulceration, or exacerbate an existing ulcer.
  • If your dog is unable to produce tears (a condition known as ‘dry eye‘) the eye may also be more susceptible to corneal ulcers. In some cases the cause of the ulcer is uncertain.

Ulcers can be very painful and your dog may resent being touched around the affected eye. Your dog may blink frequently, keep the eye partially closed, or rub at the eye. There may be a watery discharge from the eye (if the corneal ulcer becomes infected this discharge may become purulent).

The white of the eye may become reddened and if the ulcer is particularly painful the third eyelid (a protective membrane under the main eyelids) may cover the surface of the eye when the eye is open (this can give the appearance of the eye ‘rolling up into its socket’).

Your vet will try to identify the cause of the ulcer in order to choose the best treatment. The eye must be examined carefully to make sure there is nothing rubbing against the eye. Your vet may check for ‘dry eye‘ by using a small strip of filter paper placed inside the lower eyelid in order to check tear production. Local anaesthetic drops may be put in the eye to make your dog more comfortable whilst the eye is examined.

Your vet will then put a few drops of dye into the eye. This green dye sticks to the damaged areas and will show your vet how far the corneal ulcer extends.

The choice of treatment depends on the type of injury and how far it extends. If there is an underlying cause (such as a foreign body, eyelid abnormality, or dry eye) then it must be identified and treated.

For minor corneal ulcers your vet may prescribe antibiotic eyedrops or ointment. The aim of this is to prevent the ulcer becoming infected whilst it is healing. Uncomplicated corneal ulcers should heal within 5-7 days. If the ulcer takes longer than this to heal, there may be an underlying cause or complication that should be investigated.

More severe ulcers may require additional treatment and in some cases this may include surgery. Various surgical procedures are possible, depending on the type and severity of the ulcer. In difficult or protracted cases your vet may recommend referral to a specialist veterinary ophthalmologist.

During treatment, an Elizabethan collar may be necessary to prevent your dog rubbing the eye and causing further damage. As the eye heals, the area around the ulcer may become redder and small blood vessels start to grow across the eye surface to help the healing process.

When the ulcer has healed there may be a small indentation or scar left on the eye surface, but in the majority of cases this is unlikely to affect your dog’s eyesight.

Your vet is likely to ask you to put drops or ointment into your dog’s eye during the healing stage. This is relatively straightforward in most dogs with a bit of practice.

  1. Hold your dog firmly and tilt its head upwards.
  2. With the thumb and finger of the holding hand, the eyelids should be pulled gently apart and the medication given with the other hand.
  3. The tip of the tube should be held parallel with eye surface, not pointed directly at it.
  4. Expel a single drop onto the surface of the eye, taking care not to touch the surface of the eye with the tip of the dropper because this may damage the eye or spread bacteria from the eye back into the contents of the bottle.

Almost all corneal ulcers are treatable, as long as the cause and type of ulcer is identified and the correct treatment is given. Early treatment gives the best chance of a good recovery. If your dog’s eyes appear sore or red or if any abnormal discharges are present you should make an appointment to see your vet immediately.

Conjunctivitis in dogs

If your dog has a sore or red eye, or there is discharge from the eye, then it is important to contact your vet. Your dog may have an infection in the eye, but a discharge can also be caused by a foreign body (such as a grass seed) caught under the eyelid. It is important that diseases of the eye are treated quickly to prevent any permanent damage being done.

The conjunctiva is the pinkish surface surrounding the eyeball. The third eyelid is an extra protective eyelid in the dog and is also covered by conjunctiva. In normal dogs the conjunctiva is not readily visible. In conjunctivitis this membrane is inflamed and becomes red and swollen. Conjunctivitis can affect one or both eyes.

Dogs with conjunctivitis usually have a discharge from their eye(s). This can be clear and watery or thick and greeny/yellow in colour. The conjunctiva is often more visible and may be swollen, partially covering the eye. The eye(s) may be held half closed and the third eyelid is more prominent.

A number of different conditions will cause conjunctivitis. Many are sudden in onset and easily treatable. Others cause a long term disease which can be more difficult to control.

  1. Irritants, trauma (e.g. a cat scratch) and foreign bodies (e.g. grass seeds) can cause conjunctivitis. In most cases treatment is rapidly effective once the cause has been removed.
  2. Conjunctivitis in dogs usually occurs as a consequence of some other eye problem. In dogs with sagging skin, the deformity of the eyelids can make them more prone to eye infections. In some dogs the eyelids turn inwards and hairs on the eyelid can rub against the eye causing damage and increasing the risk of infection.
  3. A further problem in some dogs is abnormal tear production, inadequate lubrication of the eyes can result in damage to the eye surface.
  4. Disease of the immune system can also cause conjunctivitis. These diseases are not common but can be difficult to treat.

Usually your vet will be able to tell that your dog has conjunctivitis by a simple examination. Your vet will want to examine the eye carefully to be sure there is no damage to the eye itself. If there is no obvious traumatic cause most cases will respond to drops or ointment containing antibiotics and anti-inflammatory drugs.

It is also important to be sure that tear production in the eye is normal. Your vet will be able to do a simple test in the consulting room to check this if necessary. If a foreign body is present then this obviously needs to be removed.

If the signs are not getting better after a few days of treatment, or appear to improve only to get worse again when treatment stops, more investigation is required. Your vet will want to take a swab from the conjunctiva to look for infection. In some cases a blood sample may also be required.

If there is no infection then it can be helpful to look at a sample of cells from the conjunctiva. This sample is obtained by gently scraping the surface of the conjunctiva with a cotton wool swab or spatula. If a larger sample is required, then a section of conjunctiva taken surgically may be necessary.

In most cases conjunctivitis is treated by application of drops or ointments to the eye. Sometimes with particularly stubborn infections antibiotic treatment may also need to be given by injection or tablet.

It is essential to treat any underlying causes of conjunctivitis at the same time – if these are not dealt with the problem will keep coming back. Treatment may be needed to control problems with the immune system and if the eye is too dry then replacement tears may be required. If the tear replacements are needed they are most likely to be required lifelong.

If you are able to treat your dog’s eyes this can be done at home but regular treatment is essential. Most drops or ointments need to be administered at least 3-6 times a day. If you have any doubts as to how to give the medication prescribed, please ask your veterinary practice to give a demonstration. If you are unable to treat your dog appropriately your vet may arrange to keep it in the hospital for a few days to ensure that effective treatment is given.

Cataracts in dogs

Cataract is a disease of the lens of the eye in which the normally clear lens becomes opaque or white. This interferes with vision and can result in blindness. Many owners confuse a less serious problem of older dogs eyes with cataract. In some cases an eye specialist may be able to operate on the eye to remove the cataract.

Light enters through the front of the eye and is focused by the clear lens onto the retina, which lies at the back of the eye. Information from the retina is transmitted to the brain where processing occurs.

For the lens to work correctly, it must be perfectly clear. In cataract, the lens becomes opaque (like frosted glass) or even completely white. Light does not pass through it well in this state and vision is reduced. Severe cataracts cause blindness.

There are several different causes in dogs:

  • Cataract development can be inherited from parents in many different dog breeds. Hereditary cataracts affect both eyes – usually, but not necessarily, at the same time. Hereditary cataracts can be present at birth (congenital) or, more commonly, they may develop in young adult dogs.
  • Cataracts are common in dogs suffering from sugar diabetes due to disturbances in the metabolism of the lens caused by abnormal blood glucose levels.
  • Cataracts can arise following severe inflammation in the eye, or as a result of poisonings or nutritional imbalances.
  • Cataracts can also be associated with glaucoma (increased pressure within the eyeball), disease of the retina (at the back of the eye) and when trauma has resulted in dislocation of the lens of the eye from its normal position.

Usually owners are alerted to the fact that their pet may have a problem with its eye when they notice a whiteness of the eye. If eye disease develops gradually, dogs are often able to adapt well and use their other senses to help them get around. Dogs have very good hearing and a sense of smell and can use these to compensate for poor vision to some extent. In familiar surroundings it may be almost impossible to tell that a pet cannot see. If you are worried about your pets vision you can test it yourself using some simple exercises:

  1. Observe your dog carefully in the home environment and out of doors
    Does he appear to be having any visual difficulty?
  2. Throw light, silent objects (e.g. a ball of cotton wool) in front of your dog’s eyes
    Does he see and follow these?
  3. Construct a small obstacle course in the home, or move furniture around and away from the usual positions
    Does he see and avoid these obstacles the first time?

Repeat the above tests in daylight and in subdued lighting.

If you are concerned about the results of the report them to your veterinary surgeon and ask for a check-up for your pet.

In older dogs, the lens of the eye may take on a bluish or grayish color. Many owners believe this is a cataract. However, a simple eye examination usually provides the necessary reassurance. This problem is called nuclear sclerosis and is part of normal ageing. Vision is preserved and no specific treatment is needed.

Diagnosis is usually straightforward, and based upon visual testing of the dog and examination of the eye by a veterinary surgeon/ophthalmologist. Additional tests may be required to check for diabetes and occasionally other causes and other eye diseases.

Cataracts are treated by removing the lens from the eye. The lens is surgically removed by a specialist. There are several different techniques but one of the most popular is known as phacoemulsification (the use of ultrasound waves to break up the cataract). Once the lens has been broken up fragments can be removed through a small incision in the eye. Other surgical techniques are also possible and may be indicated in certain cases, e.g. when lens of the eye has become displaced.

Following surgery the aftercare is very important. Eye drops may be required for several months and must be applied regularly at home. If cataracts are present in both eyes, they may be removed at the same time, thus avoiding the need for further surgery in the future.