Dogs: Health, Disease and Physiology: Other health issues and physiology

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Dogs: Effect on human mental and physical health
Dogs: Health, Disease and Physiology: Digestive system
Dogs: Health, Disease and Physiology: Reproductive and urinary system
Dogs: General
Dogs: Behaviour and training
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Efficacy of the treatment of dogs with leishmaniosis with a combination of metronidazole and spiramycin

Spiramycin and metronidazole combination can offer a useful second-line treatment for dogs with leishmaniosis

source: M.G. Pennisi, M. de Majo, M. MAsucci, D. Britti, F. Vitale and R. del Maso Veterinary Record vol 156 no 11, March 12 2005 starts p346, 4 pages long

Vets can achieve a clinical cure for leishmaniosis infantum with available drugs, but not a parasitological cure. Some drugs, such as those containing antimony, are expensive and have side-effects. A spiramycin and metronidazole combination has already been successfully used with some dogs not responding to conventional treatments or relapsing, and is inexpensive and can be given orally. This study involved a total of 27 dogs infected with leishmaniosis infantum, and treated for 90 days. The control group comprised 14 dogs treated with allopurinol and meglumine antimonate, a conventional treatment, while 13 comprised a test group and were treated with spiramycin and metronidazole. The mean age for dogs in the test group was 3.5 years, and there were two females and 12 males. The mean age for dogs in the test group was 3.8 years, and there were three females and 10 males. A side effect of raised amylase levels was noted in eight control dogs and four test  dogs. Four dogs in the control group suffered side effects so severe that they were withdrawn. Eight of the remaining 10 showed a clinical improvement, while two deteriorated. One dog from the test group developed pemphigus foliaceus and was withdrawn. Ten of the remaining twelve showed a clinical improvement, and two deteriorated. The improvement was noted faster in the control group, after an average of 30 days, compared with 45 days for the test group. No dog from either group was cured parasitologically. A spiramycin and metronidazole combination appears to be a useful second-line treatment for dogs with leishmaniosis DO,HD

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Disease risks for the travelling pet: heartworm disease

Prevalence, diagnosis and treatment of heartworm disease in dogs and cats

source: Luca Ferasin

In Practice vol 26 no 7, July/August 2004 starts p 350, 7 pages long

Heartworm infection is caused by a roundworm, or nematode, called Dirofilaria immitis. Heartworm is found in regions where there are a large number of dogs and mosquitoes, and it is warm enough for long enough for heartworm larvae to develop in mosquitoes. It is usually too cool for the larvae to mature in the UK in summer, but pets that have been abroad, such as dogs, cats and ferrets, can be affected. The disease mainly affects heart and lungs. Pulmonary arteries may be blocked, and the worms may migrate to the heart, leading to right-sided heart failure. Cats generally suffer from lung infections, and are more likely to show ectopic infections than are dogs. Dogs may cough and have trouble exercising, though most cats show no symptoms. Microfilariae may be seen in fresh blood, though ELISA antigen tests are a more reliable form of diagnosis.

Treatment for heartworm depends on the severity of signs. Though adult heartworms can be killed, there are risks of pulmonary thromboembolism, especially with cats. Cats can recover when the parasites die a natural death, so killing adult heartworms is best carried out only when cats are stable, and do not respond to help with symptoms, such as cage rest, bronchodilators, fluid therapy and steroids. Seriously ill dogs should have just one dose of adulticide, to reduce risks from dead worms, with later doses after a month. Ivermectin is one method of eliminating microfilariae, after adult worms have died. Prophylactic drugs, like milbemycin oxide (Novartis Program Plus) and Pfizer's Stronghold can be given monthly to dogs at risk from infection by mosquitoes where the disease is prevalent. Milbemycin oxide and Ivermection can be toxic to collies at high doses.

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Be a good dog and you'll live a long, healthy life

Easy-to-train dogs tend to have longer lives

source: New Scientist vol 206 no 2757, 24 April 2010  p14

Vicent Careau, a researcher from Canada's University of Sherbrooke, has found that dog breeds classed as easy to train tend to live longer. He compared mortality and longevity data for different breeds, and found that bichon frises, poodles and German shepherds, tended to live longer than beagles, pomeranians and other breeds seen as difficult to train. He first controlled for the size of these breeds, since smaller breeds tend to live longer. Careau also found that breeds perceived as aggressive tend to burn  calories faster, ie to have a higher metabolic rate.
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Snot makes dogs super sleuths

Canine nasal mucus pre-sorts smells

source: New Scientist  vol 200 no 2685 November 29 2008 p18

Dogs have a network of mucus-coated nasal tubes which pre-sort smells, a process that helps the brain identify them. Smell molecules travel through the mucus at different rates. Pennsylvania State University's Brent Craven has led a team which developed computer models of the passage of air through a dog's nose, to study this phenomenon. This research is novel in that previously researchers looked at receptors for smell molecules, rather than what happened in a dog's nose before the molecules reached the receptors.
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Study of dog and cat owners' perceptions of medical treatment for cancer

Dutch study of owners' views of their cat and dogs' anti-cancer chemotherapy treatments

source: L.B. Bronden et al
Veterinary Record vol 152 no 3, January 18 2003
starts p77, 4 pages long

Cats and dogs may now be seen as part of the family, with their owners wanting the best treatments for their pets if they fall ill. Anti-cancer treatments tend to involve surgery, radiotherapy or chemotherapy. This study examines how owners of cats and dogs undergoing chemotherapy at a centre in Utrecht, Netherlands, perceived the treatment. There were 10 cat owners who answered the questionnaire, and 59 dog owners, giving a total of 69. Owners most commonly expected that chemotherapy would allow their pets to live longer, while 26.1% expected a cure. The expectations of a cure were higher than the outcome warranted, though the owners did accurately judge likely side-effects. Hair loss, diarrhoea and vomiting were the side effects that owners were most likely to expect. Cats tended to have different side effects from dogs. This may be because cats were not given doxorubicin, which was what caused most of the problems for dogs. Cats may also be less sensitive to anticancer agents, or may metabolise them differently. Pets tend to have fewer and less intense side effects than humans taking anti-cancer drugs. This may be because pets tend to be given lower doses, and humans are given more aggressive therapies, since vets often aim for palliation when they treat pets. Pets also do not face stress and worry associated with knowing that one has cancer. Owners of 15 of the pets did not notice any side effects, and the effects suffered by the other pets were mostly not severe, and only occasional. Diarrhoea and vomiting were the effects that dog owners most commonly reported, and drugs can be used to treat and help prevent these effects. Weakness and weight loss were also noted, and probably linked to diarrhoea and vomiting. Cat owners saw weight loss as the main problem.

Most of the owners saw the chemotherapy as beneficial, and this is probably linked to the high proportion of pets suffering from malignant lymphoma, a type of cancer that responds well to chemotherapy.

Family members tended to see the treatment favourably, and took part in the decisions in around half the cases. Friends and neighbours were more likely to be positive about the treatment than negative, but were not a positive as families, perhaps because families had greater knowledge of the treatment. Most of the pets were still alive when the survey was carried out. The cats had the longest survival times in terms of the mean average, while pets suffering from cancers other than lymphoma survived for the shortest period. Owners generally saw the treatment as worthwhile, even if their pets had died, and they were also satisfied with the help they had received from their vets and from oncologists. The strongly positive responses of these owners suggest that this area of treatment is rewarding and useful.
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Dietary considerations in cardiac disease

Diet and heart disease in cats and dogs

source: Antonio Moneva-Jordan
In Practice vol 25 no 2, February 2003
starts p92, 6 pages long

Heart disease is a common problem in cats and dogs, and recent research has shown that diet is important for pets with heart problems. Congestive heart failure (CHF) can lead to cardiac cathexia, or muscle wasting, which also involves lack of appetite, poor digestion, and metabolic changes. It is less common in cats than in dogs.

Pets with cardiac cathexia need diets that tackle anorexia and that regulate cytokine production. Regulation of sodium is important, but pets may refuse to eat low sodium diets. Less restricted diets that are both digestible and palatable may be better for the pet than more restricted diets they will not eat. Changes in diet should take place over a period of four to five days. Sometimes pets can be persuaded to eat by warming their food, feeding by hand, and other tricks. Some pets may do well on well-balanced homemade diets, if they have dedicated owners. Cytokine reduction can help dogs with CHF to survive longer, and fish oil supplements can help with this. Obesity should be tackled as early as possible, since it makes pets more susceptible to heart trouble by overloading their hearts, pushing up blood pressure, and making them less inclined to take exercise. Weight reduction can help reverse this overloading.

Pets with congestive heart failure (CHF) tend to retain water, sodium and chloride, and are less able to excrete dietary sodium. Low sodium diets do not appear to help dogs with cardiac disease and no overt CHF, but excess sodium and chloride should be reduced once dogs show overt CHF. Moderate restriction tends to be recommended at first, and this can involve giving pets senior foods, or foods for pets with kidney disease. All non-prescription commercial foods for cats and dogs have sodium chloride in excess of animals' requirements, and this is especially true for canned foods. Moving pets to dried rather than canned food is one way to reduce the amount of sodium they eat. Reducing sodium to too low a level could, however, worsen a pet's condition. Lack of potassium can also be a problem for pets given diuretics, and this especially applies to cats, and to pets suffering from loss of appetite. Magnesium deficiency has also been linked to treatment with diuretics.

Another dietary link to heart disease is lack of taurine, which especially affects cats. Most commercial cat foods now contain taurine, after it was discovered that low taurine levels are linked to feline cardiomyopathy. Taurine may also benefit humans, rabbits and ferrets . Taurine deficiency is a possibility for any cat with myocardial failure. Cats most likely to suffer taurine deficiency are those fed on cereal-based diets, dog food, vegetarian diets, or any other non-traditional diet. Taurine levels can be checked using blood tests, and taurine supplements given, as well as diets with more taurine. Some breeds of dogs may also suffer from taurine deficiency leading to dilated cardiomyopathy (DCM), and this includes golden retrievers, and some breeds given low protein diets to tackle bladder stones.

Carnitine deficiency has also been linked to heart disease in some dog breeds, as well as turkeys, hamsters and humans. Some dogs may benefit from carnitine supplements, though it is difficult to identify which dogs might benefit. Carnitine seems to have few side effects, so it may be prescribed in case it helps, but it is expensive.

Omega-3 fatty acids found in sea foods such as fish oils may help humans with heart disease, and reduce tumour necrosis factor in animals, including humans. Studies have shown beneficial effects when fish oil has been given to dogs with CHF and DCM.

Foods and drugs can interact in a number of ways, for example, frusemide therapy can lead to water-soluble vitamins being lost over the long term. Pets receiving diuretics for long periods need to have vitamin supplements, or vitamin-rich foods, to take this into account. Low-sodium diets combined with diuretics and angiotensin-converting enzymes (ACE) inhibitors can lead to kidney trouble, and affected pets can be treated by reducing their drug intake, or increasing their sodium intake, or both. There are also some drugs that are less effective when taken with food, and this applies to digitoxin, digoxin, and pimobendan, so these drugs should not be fed at mealtimes. Treatment of pets with heart disease therefore needs to look both at diet and at medical treatment. There are no universal recommendations for levels of magnesium, potassium, sodium or chloride. Instead, individual pets should be monitored, and their kidney function, weight, condition, and electrolyte concentrations in the blood should be checked, with changes made in line with their individual needs. There is also a need for more research in this area.
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Parasites mobilise as world warms

Global warming may foster spread of canine diseases in Europe

New Scientist vol 202 no 2704, April 18 2009 p15

Global warming will lead to an increase in canine diseases spread by flies, fleas and ticks, according to a 2009 issue of Veterinary Parasitology. Winters are milder and shorter, leading to more active ticks throughout the year. The European dog tick can transmit canine babesiosis, and, as it moves into northern Europe, this disease is becoming more common further north. Ixodes ticks can infect dogs and horses with encephalitis, and are also becoming more common. Meanwhile, dogs from Britain that have been taken to Mediterranean areas can bring back leishmaniasis. This disease is becoming more common in southern England. It is spread by sandflies, so if sandflies were able to colonise the UK because of higher temperatures, leishmaniasis could spread further in the UK.

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Disease risks for the travelling pet: Leishmaniasis

Diagnosing and treating leishmaniasis in cats and dogs

source: Lise Trotz-Williams and Luigi Gradoni
In Practice vol 25 no 4, April 2003
starts p190, 6 pages long

Several thousand pets have travelled between mainland Europe and Britain since the Pet Travel Scheme (PETS) was introduced in 2000. Pets are treated for ticks, tapeworms, and rabies, but can still contract other diseases, including leishmaniasis, which can be fatal, and can also affect humans.

Leishmaniasis refers to syndromes in animals affected by Leishmania protozoan parasites. Leishmania infantum is more common in the Mediterranean, and has also been found in North America. Leishmania chagasi is more common in Latin America. Dogs are the main reservoir for both types of Leishmania, since it is rarer for cats to be affected. Animals become infected through being bitten by sandfly carrying the parasite. The infection can spread to several organs in cats and dogs that do not have a strong enough immune system to protect them. Around half of dogs that become infected will go on to develop clinical leishmaniasis. The disease has a reported incubation period of between a month and seven years. Symptoms vary according to which organs and tissues have been invaded, and some animals may simply show dermatitis. Pets may develop 'spectacles' as the skin round the eye is affected, and their muzzles may also show signs of the disease. Cats and dogs that are seriously affected can lose their appetites, lose weight, and become depressed. The variety of possible clinical signs is wide, and includes osteomyelitis, colitis, and pericarditis, so diagnosis is not easy, but leishmaniasis should be considered when pets have travelled to areas where it is endemic.

Diagnosis can be carried out in a number of ways, including smears from skin lesions. Parasites may not be easily detectable in some cases, and diagnosis may also be carried out through testing for antibodies to leishmania. Such tests may not be accurate until a while has elapsed after the pet has become infected.

There is some risk to humans, especially children and people with HIV. However, humans in southern Europe generally appear to be at low risk of acquiring clinical leishmaniasis, despite high risks of infection.

Treatment tends to suppress clinical signs, and pets may suffer relapses, since parasitological cures are difficult to achieve. Euthaniasia may be recommended in areas where leishmaniasis is endemic, due to the risk of the disease being passed on, and of drug resistance developing. However, since sand flies and other vectors are unknown in the UK, treatment is more of an option there. Megaglumine antimoniate and allopurinal are usually given, with allopurinol continuing over the longer term, though there are other treatments, such as allopurinol given alone. Long-term intermittment treatment appears to be the best option to prolong survival rates.

Cats appear to be more resistant to leishmaniasis than dogs, and they tend to be less severely affected when they are infected. Most affected cats simply suffer from skin conditions. Treatment is the same for cats and dogs.

Leishmaniasis is especially common in Mediterranean countries, such as France, Spain and Portugal. The highest rates have been found in the Balearic Islands, Crete, Malta and Corsica. The risk varies from one locality to another, and from one season to the next. The risk is highest when there are most sand flies about, especially between May and September. Sandflies tend to be especially active from dusk to dawn, so an important precaution is to keep pets indoors at this time. Collars impregnated with deltamethrin (Scalibar collars from Intervet) can also help to protect dogs from sandfly bites and infection.
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Preliminary results of the dog and cat exotic disease surveillance scheme

Cats in Britain appear to be less vulnerable to exotic diseases than dogs

Source: Paul Mauser
Veterinary Record vol 153 no 7, August 16 2003 p220

The British government launched its Dog and Cat Travel Risk Scheme (DACTARI) in March 2003, for voluntary reporting of cats and dogs with exotic diseases, especially if they have been abroad under the Pet Travel Scheme. Cats appear to be less vulnerable than dogs, since no cases of exotic diseases were reported from March to July inclusive, while 12 dogs were reported, one with two conditions. There were eight diagnoses of leishmaniasis, four of babesoisis, and one of ehrlichiosis. Two diagnoses of leishamniasis and one of babesoisis were also reported prior to the start of DACTARI. Ten of these cases involved dogs that had travelled to France and Spain. Leishmaniasis is a disease that humans can suffer from too, and it is not easy to treat.
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Government response on cat and dog vaccination

British government responds to report on cat and dog vaccines

source: Veterinary Record vol 153 no 2, July 12 2003
starts p35, 2 pages long

The British government has backed recommendations made by a working group on vaccination for cats and dogs. The group was set up in 1999 to assess health risks arising from vaccinations. The government supports 15 of the 19 recommendations made by the group, including a recommendation that more research be carried out into links between upper respiratory tract problems in cats, and feline calcivirus vaccination. The working group called for product literature to carry statements that the duration of immunity used for booster vaccination regimes is a minimum, rather than a maximum period. The group also called for a risk-benefit analysis to be carried out for individual pets, by vets together with the pets' owners. The government sees professional development among vets as the best way to spread information, rather than through product literature. The government also claims that it encourages voluntary disclosure of information to vets and the public. The government rejected a recommendation for generic warnings to be put on injectable vaccines for cats, relating to the possible higher risk of sarcomas developing after aluminium-adjuvanted vaccines. The government argues that there is not yet enough evidence to link specific vaccines, or types of vaccines to fibrosarcomes.
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Retrospective study of 25 young Weimaraners with low serum immunoglobin concentrations and inflammatory disease

Immune function disorder in weimaraners

source: R.D. Foale et al
Veterinary Record vol 153 no 18, November 1 2003

starts p553, 6 pages long

A number of reports have mentioned apparent immune dysfunction affecting young weimaraners. This immune system defect appears to be the cause of mulitfocal inflammatory disease, or recurrent bacterial infections. Symptoms include joint pain, pyrexia, vomiting and diarrhoea. Tests have revealed low circulating immunoglobin concentrations. There are also reports of reactions at injection sites, and some researchers report that vaccination appears to trigger the syndrome. This defect appears to be inherited, since it affects littermates.

This study reviews clinical records for 25 weimaraners that had suffered more than two episodes of this syndrome. Twelve of the cases came from the University of Cambridge's Queen's Veterinary School Hospital, while the remainder came from throughout the UK. Serum samples from 15 weimaraners were used for control purposes. Anorexia and lethargy were the most common signs, affecting 20 dogs, with 13 dogs affected by diarrhoea and vomiting. There were 10 dogs for which accurate vaccination histories were available, and nine had developed signs within five days of being vaccinated. The tenth developed signs 25 days following a booster vaccination. Twenty four dogs had low levels of at least one serum immunoglobin class. Twenty one dogs were followed up, and eleven of these recovered fully, six showed occasional clinical signs, while four were euthanased. One was euthanased following a collapse after showing symptoms of the syndrome, another was euthanased following diagnosis, and a further two were euthanased for aggression, having showed signs of the syndrome prior to the aggression.

No gender predisposition was noted in this study. Like previous studies, gastrointestinal problems were predominant. Diarrhoea has previously been noted as a particular problem with weimaraners showing low serum immunoglobin concentrations. This suggests that intestinal and gastric biopsies are indicated for affected weimaraners with intestinal problems, when dietary intolerance, parasitism and infections have been excluded as possibilities.

Metaphyseal osteopathy affected eight dogs, five of whom showed good responses to NSAIDS, though two later showed a faster response to treatment with glucocorticoids. Five dogs were affected by sterile meningitis, and they all showed a good response to glucocorticoids. The syndrome could be a type of immune dysregulation, since dogs responded well to glucocorticoids at doses that were immunosuppressive.

Young weimaraners seem to be vulnerable to immunodeficiency syndrome. Diagnosis of the syndrome is indicated if dogs show two of three criteria: low serum immunoglobin levels, inflammatory disease, and the development of signs within a week of vaccination. Most of the dogs in this study responded to treatment with glucocorticoids, NSAIDS or antibiotics.
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Clinical evaluation of a nutraceutical, carprofen and meloxicam for the treatment of dogs with osteoarthritis

Three treatments for osteoarthritis in dogs assessed

source: M. Moreau et al
Veterinary Record vol 152 no 11, March 15 2003
Starts p323, 7 pages long

A double-blind study to assess the efficacy of caprofen, meloxicam and a nutraceutical as treatments for osteoarthritis has been carried out on 71 dogs for 60 days by researchers from the University of Montreal, Canada. The median age of the dogs was 68 months, with a range from 18-144 months, and they had a median weight of 38 kilos. Twenty nine of the dogs had osteoarthritis of the stifle, 27 had affected hips, and 15 had affected elbows.

The dogs treated with carprofen had Rimadyl from Pfizer, the meloxicam treatment was Metacam from Boehringer Ingelheim, while the nutraceutical was Cosequin DS from Nutramax Laboratories, a mix of chondroitin sulphate, glucosamine hydrochloride and manganese ascorbate. A fourth group was given a placebo for 30 days. One dog, a boxer, was withdrawn from the meloxicam group due to vomiting. A second dog, in the placebo group, developed myasthenia gravis and was euthanased. A third dog, a Labrador retriever in the carprofen group, was withdrawn due to toxic idiosyncratic hepatitis.

The effect of the osteoarthritis on the dogs was first measured using a comparison of ground reaction forces between the affected dogs and 10 normal dogs. The dogs were reassessed after 30 and 60 days of treatment. The dogs treated with meloxicam and carprofen showed significant improvement measured by ground reaction forces, while the dogs receiving the nutraceutical did not show such improvement. Dogs treated with meloxicam showed some GRF values returning to normal, which was not true for dogs receiving carprofen or the nutraceutical. The dogs' owners saw an improvement with meloxicam, while orthopaedic surgeons noted improvements with both carprofen and meloxicam. Only one dog showed a reaction to the treatment, the dog withdrawn with heptopathy.
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Exotic diseases reporting scheme

UK sets up scheme for reporting exotic diseases in cats and dogs

source: Veterinary Record vol 152 no 9, March 1 2003 p247

The UK Department of the Environment and Rural Affairs (DEFRA) is starting a pilot voluntary reporting schem for exotic diseases in cats and dogs. The scheme will focus on heartworm (dirofilariosis), ehrlichiosis, leishmaniosis and babesiosis, seen as most likely to be imported into the UK as a result of the Pet Travel Scheme (PETS). Vets are to provide details of the travel history and diagnostic details of suspected and confirmed cases. UK vet organizations, the British Small Animal Veterinary Association and the British Veterinary Association, have collaborated with DEFRA in setting up this scheme, but both organizations argue for a more active scheme to tackle the import of exotic diseases.
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Seroepidemiological survey of Bordatella bronchiseptica and canine parainfluenza-2 virus in dogs in Sweden

Survey of prevalence of kennel cough-related antibodies in pet dogs in Sweden

source: L.Englund et al
Veterinary Record vol 152 no 9, March 1 2003
starts p251, 4 pages long

Two organisms, Bordatella bronchiseptica and canine parainfluenza-2 virus (CPiV-2) are the most common agents linked to kennel cough, which is also called canine infectious tracheobronchitis. Either organism can induce the disease in unvaccinated dogs, though coughing tends to be less severe for dogs affected by CPiV-2 than for dogs affected by B bronchoseptica.

A survey of 302 unvaccinated dogs from eight veterinary clinics in Sweden has investigated the prevalence of antibodies in dogs against these two organisms. The dogs were all aged two years or over, and had not travelled abroad. There were 154 male and 146 female dogs, with sex not reported for the other two. The males had an average (mean) age of 5.9 years, and the females an average age of 6.4 years. Some samples had too little serum to test for both organisms. 297 samples were tested for B bordatella, 287 samples were tested for both agents, 288 for antibodies against CPiV-2, with 9 samples excluded from the CpiV-2 analysis, since the dogs had been vaccinated against CPiV-2, giving 279 samples for CPiV-2 analysis.

The results showed B bronchoseptica antibodies for 66 samples of 297, or 22% of the total, with no correlation for breed, sex, age, or various risk factors. CPiV-2 antibodies were found in 79 samples, or 28% of a total of 279. Dogs were more likely to be affected by CPiV-2 if they spent over a month in day or boarding kennels over a year, as were dogs which had mated naturally. There was no link between CPiV-2 infection and age, sex, breed, or competing in dog shows, agility or field events. There was no significant link between dogs being tested positive for B bronchoseptica and having a positive result for CPiV-2, with only 18 dogs of 287 (6.3%) testing positive for both organisms.

These two agents linked to kennel cough appear to be common in Sweden. B bronchseptica can persist in dogs' upper airways for several weeks, while CPiV-2 virus appears to be shed for a short time, and seems to be more closely linked to overcrowding. B bronchoseptica infections can occur without obvious overcrowding. Bacteriological anlaysis from pharyngeal or nasal swabs can identify cases of B bronchoseptica which would respond to antibiotics. Some areas of Sweden appear to have a higher rate of CPiV-2 infection than others, though it is unclear why.
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Bark from the dead

Terrier survives 13 days in rabbit hole

source: Sun December 21 2002 p31

A terrier has spent 13 days in a rabbit hole in Dorset, and has managed to escape alive. The dog apparently got stuckin the hole, but was able to get free after losing some weight.
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Kennel of the week

Arthritic dogs get heated pool at Belgian kennels

Source: Independent September 28 2002 p28

A kennel in Arendonk, Belgium, has been equipped with a heated swimming pool to allow arthritic dogs to take exercise. The indoor pool was the idea of Andre Verschueren, who wants to help older dogs.
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Investigation of hearing loss in dogs

source: Celia Cox
In Practice vol 24 no 9, October 2002
starts p494, 7 pages long

Dogs can hear sounds up to 67k hertz (Hz) compared with up to 20kHz for humans, though the sensitivity range is similar, which means that dogs' hearing can be tested using similar techniques to those used for humans.

Hearing loss is especially common in certain breeds, such as dalmations, with an estimated 22% affected in the UK and as many as 30% in the US. White bull terriers (19.1%), English setters (14.3%), border collies (10%) and cocker spaniels (6.8%) are also prone to hearing loss.

Hearing loss can be classified into two types: conductive deafness, such as that caused by a damaged ear canal, and sensorineural, where the cochlea is involved. Dogs may inherit conditions which lead to deafness later in life and they may suffer damage from a number of causes, such as from ototoxic drugs.

Behavioural tests involve seeing whether a dog responses to sounds from unseen stimuli, though the dog may not respond out of boredom rather than deafness, or may respond to a visual cue. A brainstem auditory evoked response (BAER) test is considered more reliable and gives more information. Pups can undergo a screening test from four weeks' old. Full hearing tests take longer, from 20-30 minutes, and the dog has to keep still, so a low dose of sedative may be used. Responses to clicks are measured to assess the degree of deafness. Ait and bone conduction tests can be carried out, and the results compared. This helps in assessing whether the problem is conductive or sensorineural.

Other investigations which can help with diagnosis include checking for clinical signs. Deafness is more likely to be noticeable in pups separated from their litters, since they can no longer communicate with their siblings by touch. Dogs deaf in both ears may have a cry that is at a higher pitch, and may show more aggression. It may also be difficult to wake them, and there is no response to loud noises. Dogs deaf in one ear have trouble identifying the location of sounds, and are more difficult to train. Otoscopy checks should be carried out on dogs with conductive hearing loss, to see whether there is a discharge or other sign of an external ear problem. Radiographs can be used to check for middle ear disorders, though magnetic resonance imaging gives more information - and is more expensive. Tympanometry can help in assessing whether deafness is sensorineural or conductive.

Conductive hearing loss can sometimes be successfully treated using surgical or medical methods, but sensorineural hearing loss cannot be treated. Breeders can use BAER tests to check for deafness when selecting breeding animals, and they can test pups before selling them. Working dogs should be tested before a lot of effort is put into training them.

Pet owners can return deaf dogs to breeders, or use special training programmes that involve a lot of body language. Deaf dogs can also benefit from the company of a hearing dog. Some dogs may benefit from hearing aids, so long as the dog has some hearing left, and will allow a hearing aid to be put in and taken out of the ear. Some owners have found vibrating collars to be helpful. The dog has to be trained to know what to do when the collar vibrates.

Deaf dogs should not be bred from, and it is best to neuter dogs with inherited deafness.
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Intradermal test reactivity to Malassezia pachydermatis in healthy basset hounds and basset hounds with Malassezia dermatitis

Research on fungal skin infection affecting dogs

source: R. Bond et al
Veterinary Record vol 151 no 4, July 27 2002
starts p105, 5 pages long

Some breeds of dogs, like basset hounds, West Highland white terriers, and cocker spaniels are prone to skin lesions associated with a yeast infection, linked to Malasezzia pachydermatis, and characterized by greasy dermatitis with a large yeast population. Affected dogs often respond to antifungal therapy, which can stop the itching. There is some evidence that basset hounds suffering from this condition may also be affected by defective cell-mediated immunity.

In this study, basset hounds and beagles were used to assess how their skin responded to M pachydermatitis antigens, using both healthy basset hounds (eight dogs), and those affected by skin lesions (17 dogs), as well as healthy beagles (19 dogs). The aim was to assess differences in intradermal responses. Two affected basset hounds and one beagle showed reactions of the wheal and flare type 15 minutes after the antibodies had been injected. Almost all of the basset hounds had reactions 24 hours after injection, whether or not they had previously been affected, while few beagles showed this reaction. Both previously affected and previously healthy basset hounds showed similar gross lesions in response to the antigen extracts.

It is unclear why the reactions were delayed, and why both healthy and affected dogs showed such a reaction. It may be that these dogs were hypersensitive to M pachydermatitis allergens, or their immune response may tend to favour colonization by M pachydermatitis. More research is needed to clarify links between this sort of response to injections of M pachydermatitis-derived substances, and the effect on dogs of colonization and yeast infection on the skin.
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Phenobarbitone concentrations in the hair, saliva and plasma of eight epileptic dogs

Saliva may not be best medium to test phenobarbitone concentrations in epileptic dogs

source: M.Dunnett et al
Veterinary Record vol 150 no 23, June 8 2002
starts p718, 7 pages long

A study of eight dogs with idiopathic epilpsy and treated with phenobarbitone, has examined phenobarbitone concentrations in saliva, plasma and hair. There was a correlation between the plasma and hair concentrations and the daily phenobarbitone dosage. Phenobarbitone hair concentrations were also linked to doses given in the six months before testing. Saliva phenobarbitone concentrations were not correlated with dose rates or with plasma concentrations. Possible reasons for these results are discussed, as are previous studies in this area. One conclusion is that saliva does not appear to be a suitable medium to assess phenobarbitone concentrations, though more rigid conditions with standardised collection procedures could change this.
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Cutaneous candidiasis in a dog caused by Candida guillermondii

Treatment of yeast infection causing skin disease in a Jack Russell

source: R.S.Mueller et al
Veterinary Record vol 150 no 23, June 8 2002
starts p728, 3 pages long

Dogs' skin and mucosa often habour yeast organisms, which could become pathogens if a dog suffers a disturbance, for example to immunological mechanisms. An eight-month old Jack Russell was found to be suffering such an infection, leading to chronic, severe, dermatitis on the groin, with crusting and scaling, which began after he was castrated. He was initially unsuccessfully treated with different drugs, including antibiotics, and then a yeast infection, Candida guilliermondii, was discovered. Treatment with ketoconazole and a shampoo which contained selenium sulphide, miconazole and chlorhexidine, brought an immediate improvement. The treatment was stopped after 10 days, when the dog developed a poor appetite, then started again for a six week period, and was eventually successful. Ketoconazole can lead to loss of appetite in small animals, and hepatototoxicity has been observed in a very few cases.
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Clinical efficacy and pharmacokinetics of carprofen in the treatment of dogs with osteoarthritis

28-day study of the effect of carprofen on six dogs

source: V.J. Lipscomb et al
Veterinary Record vol 150 no 22, June 1 2002
starts p684, 6 pages long

Six dogs of medium to large breeds were given 2mg/kg racemic carprofen a day over 28 days and this improved their lameness on average, both in terms of a visual analogue scale, and when peak vertical forces were measured for the dogs' worst affected limbs. The two older dogs, which had hip and elbow arthritis, showed obvious improvements, while two immature dogs showing hip dysplasia showed moderate improvements, and two dogs suffering elbow arthritis did not show any improvement. Carprofen acts as an analgesic, and this appears to be the reason for the improvements shown, since its long-term effect on cartilage metabolism is not known, and chondroptective (disease-modifying) action has yet to be proven. Carprofen has a low incidence of side-effects, and none were seen in this study, but it should not be given with corticosteroids, which have been associated with gastrointestinal bleeding. Pharmacokinetic differences occurred within dogs as well as between dogs, with different absorption patterns shown on different days. Carprofen is a non-steroidal anti-inflammatory drug (NSAID) and a COX inhibitor, though this effect is absent or slight in dogs at recommended doses. Racemic carprofen is a mix of two different drugs. The mechanism by which it works is unclear. Tt has been suggested both that carprofen is a COX2 inhibitor, and that it works through non-COX mechanisms. Dogs do not appear to accumulate carprofen, or develop tolerance for the drug. This study has found the disposition and absorption of carprofen enantiomers apparently non-enantioselective, with individual dogs showing some small variations. This means that there could be breed differences in terms of carprofen enantiomer pharmacokinetics.
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Management of bacterial osteomyelitis in dogs and cats

Understanding and treating bacterial osteomyelitis in cats and dogs

source: Chris May
In Practice vol 24 no 6, June 2002
starts p330, 6 pages long

Osteomyelitis is a term that is usually used to describe fungal or bacterial infections of bones, and means bone inflammation. Osteomyelitis is not usually life-threatening, but can lead to complications, especially in immature animals that have not developed their skeletons. The skeleton can also be affected by protozoan and viral infections, but these conditions are rare. Acute cases of osteomyelitis can be recognised by pain, heat and swelling, while chronic cases tend to have other characteristics such as bone death, and draining sinuses. Staphylococcus accounts for around 50% of the cases, and more than one type of bacteria may be involved. The main causes include surgery, traffic accidents, and bite and gunshot wounds. Implanted foreign material, shock and other reduced host defences, bone necrosis and fracture instability are among contributory causes. Fractures should be repaired under aseptic conditions, and antibiotics should be given to prevent infection when implants are used. Affected animals may show lameness and loss of appetite. Radiography and bone biopsies can be used in diagnosis. Treatment chronic osteomyelitis may have to involve surgery, with necrotic soft tissue and implants removed. Antibiotics many be enough for acute cases. Drainage to remove dead space can be carried out through active or passive systems. Closed, sterile, active systems are less likely to lead to secondary infections than open active or passive systems. Broad-spectrum antibiotics can be used to treat this condition. Osteomyelitis is often associated with poor blood supply, so antibiotics like tetracycline that only control, rather than eliminate infections, should be avoided. Acute cases generally have a better prognosis than chronic cases. Poor surgical techniques and asepsis are the most common cause, and the focus should be on seeking to prevent bacterial osteomyelitis.
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Periodontal disease and diet in domestic pets

Teeth cleaning, chews and control of diet texture can help prevent periodontal disease in dogs

source: Cecilia Gorrel
Journal of Nutrition vol 128 no 12, Dec 1998
starts p2712S, 3 pages long

Periodontal diseases include gingivitis, where only the gingiva is affected, and the more serious condition of periodontitis, which can lead to loss of teeth, because the root cementum, periodontal ligament and alveolar bone are affected. It is very common, probably the most common condition that vets see in small animals such as dogs. The pet may suffer discomfort, and other organs may also be affected, so it is important to prevent periodontal disease as a way of caring for pets' general health.

Dental plaque is the main cause of periodontal disease. Plaque is made up of oral debris, dead cells, salivary components, and bacteria and bacterial byproducts. Plaque rapidly accumulates on teeth, and in pockets at the base of the teeth. The reasons for accumulation in pockets are still debated, but include pocket depth. Food debris is not the problem, since plaque formation and periodontitis can occur even in dogs fed through a tube, if their teeth are not brushed, though not all dogs that develop gingivitis go on to develop periodontitis. Calculus is hardened plaque, and is not a problem in itself, though it can cause problems by encouraging plaque to be retained. Plaque microorganisms make enzymes that can digest components of pets' connective tissue, and they release chemicals like hydrogen sulphide and ammonia. The microbial products also trigger inflammation, which is damaging in itself. Anti-inflammatory drugs can help reduce attachment loss, despite having no effect on microbiota. The susceptibility of the individual host to plaque bacteria appears to be a factor, and this susceptibility may be partly inherited. Malnutrition and stress can also exacerbate the problem. Periodontitis may also progress in stops and starts, rather continuously, and more research is needed to understand why.

The texture of pet food is important, since most pets are not malnourished. Test diets of special coarse food geared to removing plaque, and dry foods supplemented by chews have both been found to be effective in studies of dogs. Toothbrushing is, however, the most effective means of controlling plaque. Antiplaque agents in toothpaste help, though they can trigger allergic reactions, and are not as effective without toothbrushing. Dietary texture also helps, but daily toothbrushing is the single best way to protect teeth and gums.
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Diet and skin disease in dogs and cats

Research on diets and supplements to control skin disease in cats and dogs

source: Tim D.G. Watson
Journal of Nutrition vol 128 no 12, Dec 1998
starts p 2783S, 7 pages long

Skin disease can be linked to diet in dogs and cats, for example if they cannot absorb nutrients in their food due to illness, or because the food has not been stored properly or is poorly formulated. Symptoms linked to nutritional deficiencies can include hair loss and greasy skin, and there may be infections.

Dogs and cats need essential fatty acids such as linoleic acid, and they may also need polyunsaturated fatty acids (PUFA). Some low quality dry food, or poorly stored food may be deficient. The effects of deficiency may occur after two to three months, and food supplements can bring an improvement after three to eight weeks. A mix of fish oil and vegetable oil can help, though it is better to feed a veterinary supplement with zinc, vitamin E and essential fatty acids, or better quality pet food. Supplements can help with other skin conditions, such as flea allergies.

Protein deficiencies are not often found in cats and dogs, though young animals, and those that are nursing or pregnant may suffer such deficiencies. Zinc deficiency can be linked to skin trouble such as hair loss and crusts, which may become infected. High calcium levels in diet may affect zinc absorption, and cheap dry foods based on cereals and soya, can cause problems. Vitamin A deficiency is linked to skin trouble, but cases are rare, and too much vitamin A is toxic. Vitamin E deficiency can affect cats fed oily fish, and more vitamin E is needed as PUFA intake increases. Vitamin B deficiency can also be linked to skin problems, and brewers yeast, or other supplements that provide the whole B group can remedy this.

Designing experiments to understand links between diet and skin problems is not easy. The background diet is important, as well as any supplements given. The ratio of (n-6) to (n-3) fatty acids may be important, and restricting protein sources may also be a factor. Marine fish oil does, however, appear to be beneficial for dogs with skin trouble, and the absolute amount of fish oil appears to be more important than the ratio to other components of diet. Sensitivity to diet may be linked to skin disease, but this is rare, and skin disease tends to have a number of causes. Elimination diets fed for a minimum three weeks can be used to test for sensitivity to certain foods. The animal is first fed a diet that excludes foods it has already eaten, and is then fed ingredients from its former diet to see if a reaction occurs. Dairy and beef proteins, eggs, gluten and lactose may all trigger allergic responses in some animals. Home-prepared elimination diets may be better than commercial food, when diagnosing food allergies.
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Barking mad

Risks of giving Prozac to dogs

source: Andrea Lord
New Scientist January 26 2002
p38

Dogs and other pets are sometimes given Prozac or similar drugs to deal with repetitive behaviour, or stereotypies, but this may be inappropriate and could lead dogs to develop symptoms similar to those of Parkinson's disease. Prozac is a drug used to boost serotonin, and this and similar drugs, appears to help people who show flexible repetitive behaviour, but Prozac doesn't help with behaviour where the same action is endlessly repeated. An example of flexible, or variable, repetitive behaviour is grooming different parts of the body. Vets often can't tell the difference between the two sorts of behaviour, researchers argue, and too much Prozac can have side effects. This is because Prozac inhibits movement of all kinds, and too much of it makes people sluggish, as though they have Parkinson's disease, a condition which involves too low a level of dopamine being produced by the brain.
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Feed your dog's brain

Hills claims new dog food can counter effects of senility

source: New Scientist
January 26 2002
p25

Hills Pet is a US company that claims to have developed a dog food that counters the effects of senility. Dogs can suffer from canine cognitive dysfunction, which causes symptoms that are similar to those found in humans suffering from Alzheimer's disease. The food does not appear to have any effect on young dogs but does appear to be beneficial to older dogs aged between 10 and 13-years-old. Older dogs seem to have a better disposition, defecate less indoors, and learn more easily, after a year on the new food. Hill argues that it is because the food has antioxidants to counter the impact of free radicals, which have a damaging effect on the brain.
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A real eye-opener

Gene therapy restores sight to dogs with rare inherited condition

source: Philip Cohen
New Scientist May 5 2001
p17

Researchers at the University of Pennsylvania, Philadelphia, have restored the sight of dogs with blindness caused by Leber congenital amaurosis, an inherited condition which affects the retina, and which is also found in humans. The dogs were found to have a defective gene for RPE65, a protein. A properly functioning copy of this gene was engineered into a virus, and then injected into the dogs' retinas. Pupil function and electrical activity improved, and this was not the case with control animals, which just had the gene injected into the fluid of their eyes, or no injections. The dogs that had the treatment were also able to navigate obstacles better than the controls could. This research could help with developing treatments for blindness in people.
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Longevity of British breeds of dog and its relationships with sex, size, cardiovascular variables and disease

British study of lifespan averages for dog breeds

source: A.R. Michell
Veterinary Record vol 145 no 22, November 27 1999
starts p 625, 5 pages long

A British study has recorded links between dog breeds and longevity, using a questionnaire covering 3,126 dogs. The dogs lived for a mean average of 11 years 1 month, rising to 12 years 8 months for those dying of natural causes, while the median average was 12 years for all dogs, and 13 years 2 months for dogs dying of natural causes. One dog survived to 22 years, and 8% of dogs survived to be over 15 years, while 26% reached 14 years or more. Neutered bitches lived longest of dogs dying of all causes, though entire bitches lived longest of dogs dying of natural causes.

Neutered females dying of all causes (720 bitches) lived 12 years on average, compared to 10 years 10 months for entire females (833 bitches). Neutered females dying of natural causes (57 bitches) lived 12 years 11 months on average compared with 13 years 3 months for entire females (71 bitches). Neutered males dying of all causes (291 dogs) lived 10 years 8 months on average compared with 10 years 11 months for entire males (1,277 dogs) Neutered males dying of natural causes (15 dogs) lived on average 11 years 11 months, compared with 12 years 2 months for entire males (110 dogs). Neutered dogs and bitches were less likely to die of cancer, and more likely to die of heart disease than entire dogs and bitches. Neutered bitches were also more likely to die of liver disease than entire bitches.

Cancer was the most common cause of death in the groups as a whole, accounting for 44.9% of deaths of entire males, 34.7% of deaths of neutered males, 50.2% of deaths of entire females, and 39.6% of deaths of neutered females. Heart disease accounted for 34.7% of deaths in neutered males compared to 22.5% for entire males, and 23.6% of deaths of neutered females compared to 20.3% of entire females.

Jack Russells and Staffordshire bull terriers were overrepresented among dogs killed in traffic accidents, with such accidents accounting for 3.2% of all deaths. Corgis, Staffordshire bull terriers, and weimaraners were overrepresented among those euthanased due to behavioural problems, with German shepherds and rottweilers underrepresented. Only 2% of all the deaths were due to euthanasia as a result of behavioural problems. Irish wolfhounds, rottweilers, and Afghan hounds were overrepresented among dogs dying of cancer, in descending order, while beagles, Cavalier King Charles spaniels, and Dachshunds were underrepresented, in ascending order, with no cases at all recorded for the beagles.

Breeds vary greatly in terms of longevity. Breeds recorded as having a median age at death of 14 years or over were Bedlington terriers, miniature dachshunds, miniature poodles, Tibetan terriers, toy poodles, and whippets. Breeds with a median age at death of between 13.0 - 13.9 years were beagles, border collies, border terriers, Cairn terriers, chihuahuas, chow chows, collies, cross-breeds, dalmations, greyhounds, Jack Russells, Pekineses, Shetland sheepdogs, shi-tzus, English springer spaniels, and wire-haired fox terriers. Breeds with a median age at death of 12.0 - 12.9 years included golden retrievers, labrador retrievers, rough collies, West Highland white terriers, and Yorkshire terriers. Cocker spaniels, Irish setters and old English sheepdogs were in the 11.0 - 11.9 year range, and boxers, cavalier King Charles spaniels, German shepherds and Staffordshire bull terriers in the 10.0 - 10.9 year range, while deerhounds, dobermanns, flat-coated retrievers, Lhasa apsos, Rhodesian ridgebacks and rottweilers were in the 9.0 - 9.9 range. Breeds with a median age at death of under nine years were Bernese mountain dogs, bulldogs, bullmastiffs, great danes, Irish wolfhounds, miniature schnauzers and St Bernards.There does not appear to be a link between blood pressure, heart rate, and longevity.

There have been studies carried out in other countries of breeds and longevity, and there are both similarities and differences with this British study. Euthanasia for behavioural problems is more common in the US. Data based on national populations show breed differences. A study of Swedish dogs also found Irish wolfhounds and boxers to be vulnerable to cancers, though the Swedish study found greyhounds and some other breeds more vulnerable than did this British study.
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Cancer in dogs in Norway

Survey of canine cancers by Norwegian vets

source: K. Nordstoga et al
European Journal of Companion Animal Practice, vol VII(1) April 1997
starts p41, seven pages long

Initial results of a Norwegian study of cancer in dogs have become available. The project has been carried out by a number of bodies, including the Norwegian College of Veterinary Medicine. Dogs tend to suffer from different types of cancer from humans, and cancers tend to develop faster than in humans. Norway does not have a stray dog population, and most dogs are not neutered.

The total number of tumours recorded by the Canine Cancer Registry for 1990-1994 was 7,327, of which some 60% were malignant or potentially so. Mammary gland tumours accounted for 2,238 or 30.5% of total tumours, 2,220 affecting bitches and 16 affecting dogs, and 91% of mammary gland tumours were malignant. Epithelial skin tumours accounted for 990 tumours, 527 affecting bitches and 446 affecting dogs. There were 529 cases of cutaneous hystiocytoma affecting 218 bitches and 305 dogs. Malignant soft tissue tumours accounted for 452 cases, and mastocytoma for 449 cases. The dog's sex was not always recorded.

Boxers are the breed with the highest risk of developing tumours, followed by Flat-coated Retrievers, with these two breeds well above average. They are followed by English Cocker Spaniels, Giant Schnauzers, Rottweilers, Bernese Mountain Dogs, and English Setters, in descending order of risk. Dobermanns, Labrador Retrievers, German Pointers, Dachshunds, Golden Retrievers, Irish Setters, and Poodles also have higher than average risk, again in descending order, with Poodles close to the average for all breeds.

Dunkers have the lowest risk, followed by Elkhounds, Papillons, Finnish Hounds, Collies, Border Collies, Cavalier King Charles Spaniels, St Bernards, Tibetan Spaniels, Beagles, and Shetland Sheepdogs, in ascending order of risk. Bichon Frises, Pointers, Siberian Huskies, Newfoundlands, Gordon Setters and German Shepherds have lower than average risk, again in ascending order, with German Shepherds close to the average for all breeds.

Some breeds are more vulnerable to particular types of tumour, such as Bernese Mountain Dogs, more vulnerable to sarcomas, and Dachshunds, more vulnerable to mammary gland cancers, though their overall rates are not very different. Further research on breeds and tumours will be published in due course.
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