Veterinary · Clinical · also MSVE VMD-513, Small Animal Practice
Everyday dog and cat practice: puppy and kitten care, vaccination and parasite control, nutrition, the common diseases by system, behaviour, old age and emergencies.
In the exams: NAVLE canine 25.6% and feline 24.3% (about half the exam); RCVS SME companion animal 175 of 367 items; AVE Paper 2 dogs at least 14; China comprehensive paper dog and cat 25
Companion animal practice is the everyday medicine of dogs and cats: keeping healthy animals healthy, finding out quickly what is wrong with a sick one, and helping owners make decisions from the first puppy visit to the last appointment. It covers preventive care (vaccination, parasite control, nutrition, neutering and dental care), the common presentations by body system, behaviour, old age, end-of-life care and the emergencies that arrive without warning. The dog is an omnivore and the cat an obligate carnivore that hides illness, and many mistakes in practice come from treating a cat as a small dog.
The subject matters because it is where most of the world's new veterinary graduates work, in cities from Delhi to Nairobi to Toronto, and because it touches public health directly: rabies, Toxocara, Echinococcus, dermatophytes, Leptospira and antimicrobial resistance all pass between pets and people. Practice differs by country. Rabies is endemic in much of Asia and Africa and absent from others; heartworm, leishmaniosis and tick-borne diseases follow climate and vectors; drug approvals, controlled-drug law and the legal age for rabies vaccination vary. This manual gives the principles that hold everywhere and says where local rules or products differ.
Examiners weight it heavily. Dogs and cats together make up about half of the NAVLE species blueprint (canine 25.6%, feline 24.3%), 175 of 367 items in the RCVS Statutory Membership Examination, at least 14 dog items and 6 cat items in AVE Paper 2, and a 25-item dog and cat section in China's comprehensive paper. These exams are case vignettes: a signalment, a history and a few results, then the most likely diagnosis or the next step. Indian PG and service exams ask more direct recall: vaccine schedules, zoonotic parasites, breed predispositions and named tests. Doses are given only where they are standard teaching values, and every one must be checked against the label and your national formulary before use.
A breed is a closed population selected for appearance or work, and closed populations concentrate harmful recessive alleles and extreme conformations. The practitioner uses breed as a clue in the differential list and as a reason for screening. Brachycephalic breeds (English and French Bulldog, Pug, Persian) carry brachycephalic obstructive airway syndrome, corneal ulcers and dystocia; several European countries now restrict breeding for extreme conformation, and welfare bodies ask vets not to normalise it. Chondrodystrophic breeds such as the Dachshund are predisposed to intervertebral disc extrusion. The Cavalier King Charles Spaniel carries early myxomatous mitral valve disease and Chiari-like malformation with syringomyelia. Large and giant breeds carry hip and elbow dysplasia, osteosarcoma, gastric dilatation-volvulus and dilated cardiomyopathy (notably the Dobermann). The German Shepherd carries exocrine pancreatic insufficiency, anal furunculosis and degenerative myelopathy (an SOD1 mutation); the Dalmatian carries urate urolithiasis (SLC2A9) and congenital deafness.
Collies, Australian Shepherds, Shetland Sheepdogs and related herding breeds may carry the ABCB1 (formerly MDR1) deletion, which removes P-glycoprotein from the blood-brain barrier; affected dogs develop neurotoxicity from macrocyclic lactones at high doses, loperamide and some cytotoxic drugs, and a DNA test is available. In cats, the Maine Coon and Ragdoll carry breed-specific MYBPC3 mutations associated with hypertrophic cardiomyopathy, the Persian and related breeds carry autosomal dominant polycystic kidney disease (PKD1), and the Scottish Fold's folded ear is caused by a dominant TRPV4 variant that also causes painful osteochondrodysplasia in every affected cat, which is why many welfare bodies oppose breeding it. Hip dysplasia is screened by radiographic schemes that differ by country (the FCI A to E grades, the BVA/KC score, the OFA grades) and by distraction-index methods. A DNA test finds a known variant; a clear result says nothing about other diseases in the breed.
The bitch is monoestrous and non-seasonal, with an interoestrous interval that varies by breed and individual, commonly around six to seven months. Pro-oestrus and oestrus each last about nine days on average but vary widely, so mating by calendar fails. Ovulation follows the preovulatory LH surge by about two days, and serial serum progesterone, supported by vaginal cytology (over 80–90% superficial cells in oestrus), is the practical way to time mating or insemination. Gestation is about 63 days from ovulation and about 65 days from the LH surge, but 57 to 72 days from a single mating, because sperm survive for days. The queen is seasonally polyoestrous, cycling with long days, and is an induced ovulator: coitus triggers ovulation. Gestation is about 63 to 65 days.
Cats have blood types A, B and the rare AB, and type B cats carry strong natural anti-A antibodies. A type B queen mated to a type A tom produces type A kittens that absorb anti-A antibodies from colostrum and haemolyse in the first days of life: neonatal isoerythrolysis. It is prevented by typing breeding cats, which matters in breeds where type B is common such as the British Shorthair and the Devon and Cornish Rex, and by keeping at-risk kittens off the queen for the first day. The same antibodies make an untyped feline transfusion dangerous even the first time. Pyometra, a common reason for emergency surgery in intact bitches, is covered under emergency medicine.
Neonates cannot regulate body temperature, have small glycogen stores and lose water fast, so hypothermia, hypoglycaemia and dehydration form a triad that kills fading puppies and kittens; warm the neonate before feeding it. Colostrum gives almost all passive immunity and must be taken in the first day, before gut closure. Neonates should be weighed daily; a healthy puppy roughly doubles its birth weight in the first 10 to 14 days, and a pup that stops gaining is the earliest sign of trouble. Orphans need a species-specific milk replacer (cow's milk is too low in energy and protein and too high in lactose), frequent feeds in the first week, and stimulation of the perineum after each feed until about three weeks, when they begin to urinate and defecate on their own. Solid food is introduced from three to four weeks and weaning is complete at around six to eight weeks.
The first consultations set habits for life. Examine for congenital defects (cleft palate, umbilical and inguinal hernia, heart murmur, retained testes), start vaccination and deworming, discuss diet, socialisation and house training, and permanently identify the animal. Microchips follow ISO 11784/11785; several countries make them compulsory for dogs. Timing of neutering is debated: in cats, neutering by about four to five months prevents unwanted litters without increased risk; in some large dog breeds, cohort studies link early neutering to more joint disease and some cancers, while spaying before the first oestrus sharply reduces mammary tumour risk. Advise on the individual dog, its breed and its home, and follow national law, which in some countries restricts routine neutering.
The World Small Animal Veterinary Association (WSAVA) vaccination guidelines, updated in 2024, divide vaccines into core (every dog or cat, everywhere, because the disease is severe and widespread), non-core (given according to lifestyle and local risk) and not recommended (insufficient evidence). Core vaccines for dogs protect against canine distemper virus, canine adenovirus (the CAV-2 vaccine also protects against infectious canine hepatitis caused by CAV-1) and canine parvovirus type 2. Core vaccines for cats protect against feline panleukopenia virus, feline calicivirus and feline herpesvirus-1. Rabies is core wherever it is endemic or required by law. Non-core vaccines for dogs include Leptospira, Bordetella bronchiseptica, canine parainfluenza virus, Borrelia burgdorferi and, in some countries, canine influenza and Leishmania. For cats, feline leukaemia virus (FeLV) vaccination depends on exposure risk; WSAVA and the AAHA/AAFP feline guidelines advise vaccinating kittens and young cats against FeLV wherever exposure is possible, because young cats are most susceptible.
The schedule is built around maternally derived antibody (MDA), which protects the neonate but also neutralises vaccine virus. MDA wanes at an unpredictable age, in some pups not until 12 weeks or later. WSAVA therefore advises starting core vaccination at six to eight weeks, repeating every two to four weeks until 16 weeks of age or older, then giving a further dose at 26 weeks (or at one year) to catch any animal that failed to respond because of MDA. After that, modified-live core vaccines give years of immunity and need be given no more often than every three years. Killed or subunit vaccines, including Leptospira and most Bordetella and FeLV products, give shorter immunity and are usually boosted annually. Rabies schedules are set by law and product licence, not by WSAVA; a first dose at about 12 weeks is typical.
Serum antibody to canine distemper virus, canine parvovirus and feline panleukopenia virus correlates well with protection, so an in-practice or laboratory titre test can show that a revaccination is unnecessary or that a puppy has responded. Antibody to feline calicivirus, feline herpesvirus, Leptospira or Bordetella does not predict protection in the same way. Rabies titres measured by a fluorescent antibody virus neutralisation test are used for pet travel, where a common threshold is 0.5 IU/mL; they prove vaccination, not protection.
Adverse events are uncommon and usually mild: lethargy, fever, local swelling. Acute hypersensitivity with facial oedema or anaphylaxis can occur within minutes to hours. Feline injection-site sarcoma is a rare, aggressive tumour linked to chronic inflammation at injection sites; guidelines advise injecting as low on a limb or the tail as practical, recording the site, and investigating any lump that persists three months after injection, is over 2 cm, or is growing a month after injection (the 3-2-1 rule). Modified-live vaccines should not be given to pregnant animals or to kittens under about four weeks, because vaccine panleukopenia virus can damage the developing cerebellum. In shelters, where exposure is certain, core vaccination starts at four to six weeks and is repeated every two weeks, and incoming adults are vaccinated on arrival. In an outbreak of parvovirus the vaccine is still given, since it produces protection within a few days in a dog without interfering MDA.
Toxocara canis passes to pups across the placenta and in milk, so almost every pup is born infected; Toxocara cati passes to kittens in milk, not across the placenta. Both are zoonotic: larval migration in children causes visceral and ocular larva migrans. The European Scientific Counsel Companion Animal Parasites (ESCCAP), the Companion Animal Parasite Council (CAPC) in North America and the Tropical Council for Companion Animal Parasites (TroCCAP) advise deworming pups every two weeks from two weeks of age until two weeks after weaning, and kittens from three weeks, then at least monthly to six months. Adults are dewormed on a risk-based schedule or after faecal testing; in households with young children, monthly treatment or testing is often advised. Hookworms (Ancylostoma, Uncinaria) cause anaemia in pups and cutaneous larva migrans in people.
Dipylidium caninum uses the flea as intermediate host, so tapeworm segments on a pet mean a flea problem. Taenia species come from eating prey or raw offal. Echinococcus granulosus (dogs fed ruminant offal) and Echinococcus multilocularis (foxes and dogs eating rodents, in the northern hemisphere) cause hydatid and alveolar echinococcosis in people, which are serious; praziquantel is the cestocide that kills them, and some rabies-free countries require a tapeworm treatment before a dog enters. Giardia duodenalis is a common cause of diarrhoea in young dogs and cats; it is diagnosed by faecal antigen test or flotation and is not always zoonotic because many dog and cat assemblages are host-adapted. Angiostrongylus vasorum, a lungworm acquired by eating slugs and snails, causes cough and a bleeding disorder in dogs in parts of Europe and the Americas.
Ctenocephalides felis is the common flea of both dogs and cats. Only a small fraction of a population lives on the animal as adults; eggs, larvae and pupae are in the environment, so every pet in the home must be treated for long enough to outlast pupae. Isoxazolines (afoxolaner, fluralaner, sarolaner, lotilaner) are oral or spot-on ectoparasiticides that kill fleas and ticks for one to three months; regulators have added warnings about neurological adverse events, so use them with care in animals with a seizure history. Permethrin, safe in dog spot-ons, is highly toxic to cats, and a cat that grooms a treated dog can be poisoned. Ticks transmit Ehrlichia canis and Babesia (Rhipicephalus sanguineus is the tropical kennel tick), Anaplasma and Borrelia burgdorferi (Ixodes), and Hepatozoon (by ingestion). Sandflies transmit Leishmania infantum around the Mediterranean, in the Middle East, Asia and South America; repellent collars containing deltamethrin reduce bites, and vaccines exist in some countries.
Dirofilaria immitis, the heartworm, is transmitted by mosquitoes wherever the climate allows larvae to develop. Prevention is a macrocyclic lactone given monthly (or as a long-acting injection) through the transmission season or all year; it kills larvae from the previous month. Dogs are tested annually with an antigen test, which detects adult female worms, plus a microfilaria test. The American Heartworm Society treatment protocol combines a macrocyclic lactone, doxycycline to kill the Wolbachia endosymbiont, and three injections of melarsomine (one, then two a month later 24 hours apart), with strict exercise restriction to limit thromboembolism. Cats are aberrant hosts with few worms; they present with heartworm-associated respiratory disease or sudden death, antigen tests often miss them, and there is no approved adulticide, so prevention matters.
The cat is an obligate carnivore. It has a high protein requirement and keeps gluconeogenesis running all the time, cannot synthesise enough taurine (deficiency causes dilated cardiomyopathy and central retinal degeneration), cannot make enough arginine (a single arginine-free meal can cause hyperammonaemia), needs preformed vitamin A because it cannot convert beta-carotene, needs dietary niacin and arachidonic acid, and tolerates vegetarian diets poorly. The dog is an omnivore that can be fed a wider range of diets. A commercial food should state that it is complete and balanced for the life stage by the standard used in its market (AAFCO in North America, FEDIAF in Europe, national standards elsewhere).
Energy needs start from resting energy requirement, RER = 70 x (body weight in kg)^0.75 kcal per day. Maintenance energy requirement is RER multiplied by a life-stage factor; commonly taught factors are 1.6 for a neutered adult dog, 1.8 for an intact adult dog, 1.2 for a neutered adult cat and 1.4 for an intact cat, with growth needing about 3 x RER in young puppies falling to 2 x RER. For weight loss, feed about 1.0 x RER of the target weight in dogs and 0.8 to 1.0 x RER of the target weight in cats. These factors are starting points; individual needs vary by 20% or more, so reweigh and adjust. The WSAVA Global Nutrition Guidelines ask for a nutritional assessment at every visit: body weight, a nine-point body condition score (ideal 4 to 5 of 9, each point above 5 about 10% overweight), a muscle condition score and a diet history.
Obesity is the commonest nutritional disease of dogs and cats in wealthy countries and shortens life: in a lifetime study of paired Labrador Retrievers, dogs fed 25% less than their siblings lived longer and developed osteoarthritis later. A weight-loss plan sets a target weight, a measured daily ration of a high-protein, high-fibre diet, loss of about 1–2% of body weight per week in dogs and 0.5–2% in cats, and monthly weigh-ins. Rapid weight loss in cats is dangerous: an overweight cat that stops eating can develop hepatic lipidosis within days, and the treatment is aggressive feeding through a tube.
Large-breed puppies need a diet with controlled calcium and energy; excess calcium, including from supplements added to a complete food, causes developmental orthopaedic disease. Therapeutic diets have evidence behind specific uses: restricted phosphorus in chronic kidney disease, dissolution diets for struvite uroliths, hydrolysed or novel-protein diets for adverse food reactions, iodine-restricted food for feline hyperthyroidism, and highly digestible or fibre-modified diets for gastrointestinal disease. Raw meat diets carry Salmonella, Listeria and antimicrobial-resistant bacteria, a risk to the pet and to people in the home. Home-made diets are frequently unbalanced unless formulated by a veterinary nutritionist. Since 2018, investigations have examined whether some grain-free, legume-rich dog diets are associated with dilated cardiomyopathy; the link is unproven and contested, but a dog with DCM should have its diet history taken. Refeeding a starved animal too fast can cause refeeding syndrome, with low phosphate, potassium and magnesium; start at a fraction of RER and increase over several days.
Pruritus is the most common skin complaint, and it is worked up in a fixed order. First rule out ectoparasites: fleas (flea combing, response to strict flea control), Sarcoptes scabiei (intensely itchy ear margins, elbows and hocks, a positive pinnal-pedal reflex, skin scrapings often negative, so a treatment trial is diagnostic), Demodex, Otodectes and Cheyletiella. Next, identify and treat secondary infection using cytology: cocci mean staphylococcal pyoderma, usually Staphylococcus pseudintermedius; peanut-shaped yeasts mean Malassezia. Then investigate allergy. Flea allergy dermatitis concentrates on the caudal back, tail base and thighs. Adverse food reaction is diagnosed only by an elimination diet of a hydrolysed or truly novel protein fed strictly for about eight weeks, followed by a provocation challenge; serum tests for food allergy are unreliable. Canine atopic dermatitis is a clinical diagnosis made after parasites, infection and food have been excluded; typical dogs start before three years of age with pruritus of the face, ears, paws, flexures and ventrum. Allergen skin or serum testing is used to choose allergens for allergen-specific immunotherapy, not to make the diagnosis.
Atopic dermatitis is managed for life with several tools together: treat flares and infections, restore the skin barrier, control pruritus with glucocorticoids, ciclosporin, a Janus kinase inhibitor (oclacitinib) or an anti-interleukin-31 monoclonal antibody (lokivetmab), and consider immunotherapy, the only option that changes the course of the disease. Cats show allergy differently: head and neck pruritus, self-induced symmetrical alopecia, miliary dermatitis or lesions of the eosinophilic granuloma complex.
Superficial pyoderma presents as papules, pustules and epidermal collarettes and is almost always secondary. Topical chlorhexidine treatment is often enough; systemic antimicrobials, when needed, are chosen by national or ISCVD guidelines, and culture is required if cytology shows rods, lesions recur, or the dog has had previous antimicrobials, because methicillin-resistant S. pseudintermedius is now common.
Demodex canis is a normal inhabitant of hair follicles; disease arises when immune control fails. Juvenile demodicosis often resolves, but the dog should not be bred; adult-onset demodicosis is a marker of an underlying disease such as hyperadrenocorticism, hypothyroidism, neoplasia or immunosuppressive treatment, which must be searched for. Deep skin scrapes or hair plucks show the mites. Isoxazolines are now widely used to treat it; older macrocyclic lactone regimens are dangerous in ABCB1-mutant dogs.
Dermatophytosis, most often Microsporum canis, causes circular alopecia and scaling and is zoonotic, especially for children. Classic texts state that only about half of M. canis infections fluoresce apple-green under a Wood's lamp; the 2017 international consensus guidelines report much higher rates with good technique, but either way a negative lamp does not rule it out; fungal culture or PCR confirms it. Treatment combines systemic itraconazole or terbinafine, whole-body topical therapy (lime sulfur or miconazole with chlorhexidine) and environmental cleaning, continued until cultures are negative.
Otitis externa is approached through primary causes (allergy, ear mites, foreign bodies, endocrine disease), predisposing factors (pendulous or hairy ears, swimming, stenosis) and perpetuating factors (infection, chronic change, otitis media). Ear cytology at every visit guides treatment. Recurrent otitis nearly always has an untreated primary cause, usually atopic dermatitis or food reaction.
The first step is to separate vomiting (active abdominal effort, often bile) from regurgitation (passive, undigested food, no prodrome), because regurgitation points to the oesophagus: megaoesophagus, sometimes from acquired myasthenia gravis (diagnosed by acetylcholine receptor antibody), vascular ring anomalies in pups, or oesophageal foreign body. Diarrhoea is classed as small-bowel (large volume, weight loss, melaena, little urgency) or large-bowel (small volumes, mucus, fresh blood, tenesmus, urgency). Most acute diarrhoea in otherwise well dogs is self-limiting and responds to diet and fluids; current European and international guidance advises against antimicrobials unless there are signs of sepsis.
Canine parvovirus enteritis affects unvaccinated young dogs: vomiting, haemorrhagic diarrhoea and leucopenia. A faecal antigen test supports the diagnosis (recent modified-live vaccination can give a weak positive). Treatment is supportive: intravenous fluids, antiemetics, early enteral nutrition, glucose and potassium as needed, and antimicrobials for neutropenic or septic dogs; isolation and bleach-based or equivalent disinfection are essential because the virus survives for months. Foreign bodies are common in young dogs; in cats, check under the tongue for a linear foreign body (thread) that plicates the intestine.
Pancreatitis presents with vomiting, anorexia and abdominal pain in dogs, but often only lethargy and anorexia in cats. Pancreatic lipase immunoreactivity (canine or feline, cPLI or fPLI) with abdominal ultrasound supports the diagnosis. Treatment is supportive: fluids, analgesia, antiemetics and early feeding; the old advice to starve has been dropped. In cats, pancreatitis may occur with cholangitis and inflammatory bowel disease, called triaditis.
Chronic enteropathy means gastrointestinal signs for three weeks or more after other causes (parasites, extra-intestinal disease such as hypoadrenocorticism, pancreatic insufficiency) are excluded. It is classified by response: food-responsive (the largest group, treated with a hydrolysed or novel protein diet), microbiota-related or antibiotic-responsive, immunosuppressant-responsive, and non-responsive. Protein-losing enteropathy, seen with lymphangiectasia, is serious. Serum cobalamin is measured because hypocobalaminaemia is common and is supplemented. In older cats, small-cell alimentary lymphoma and chronic enteropathy look alike and need full-thickness or endoscopic biopsies with immunohistochemistry to separate. Exocrine pancreatic insufficiency, commonest in German Shepherds from acinar atrophy, causes weight loss with voluminous faeces and a ravenous appetite; a low serum trypsin-like immunoreactivity (TLI) confirms it, and it is treated with pancreatic enzyme supplements and cobalamin.
Portosystemic shunts carry portal blood past the liver. Congenital extrahepatic shunts are typical of small breeds such as the Yorkshire Terrier, and intrahepatic shunts of large breeds. Signs are stunting, hepatic encephalopathy after meals, and ammonium urate crystals; pre- and post-prandial bile acids or ammonia support the diagnosis, and imaging finds the vessel. Medical management (lactulose, a moderately protein-restricted diet, antimicrobials) is followed where possible by surgical attenuation. In cats, the common liver diseases are hepatic lipidosis and cholangitis. Many drugs, toxins and endocrine diseases raise liver enzymes in dogs, and the steroid-induced alkaline phosphatase isoenzyme makes a raised ALP in a dog far less specific than in a cat.
Azotaemia is classified as prerenal, renal or postrenal. Urine specific gravity taken before fluids is the key: an azotaemic dog with urine over about 1.030, or cat over about 1.035 to 1.040, is concentrating and probably prerenal; isosthenuria (1.008–1.012) with azotaemia points to kidney disease. Acute kidney injury in dogs comes from leptospirosis, ethylene glycol, NSAIDs, grapes and raisins, and hypotension; in cats, every part of true lilies (Lilium) and day lilies (Hemerocallis) is nephrotoxic, even pollen. Treatment targets the cause, restores perfusion without fluid overload, and monitors urine output.
Chronic kidney disease is common in older cats and less common in dogs. The International Renal Interest Society (IRIS) stages CKD in a stable, hydrated patient by fasting creatinine: in dogs, stage 1 is below 125 µmol/L (1.4 mg/dL), stage 2 is 125–250 (1.4–2.8), stage 3 is 251–440 (2.9–5.0) and stage 4 is over 440 (over 5.0); in cats the stage 2 lower limit is 140 µmol/L (1.6 mg/dL) and the other cut-offs are the same. Symmetric dimethylarginine (SDMA) rises earlier and can move a patient up a stage. Each stage is substaged by urine protein:creatinine ratio (non-proteinuric below 0.2; proteinuric above 0.5 in dogs and above 0.4 in cats) and by systolic blood pressure (below 140 mmHg normotensive, 160 or more hypertensive, 180 or more severely hypertensive, when target-organ damage becomes likely).
Management is by stage. A renal diet with restricted phosphorus prolongs survival from stage 2 onward; phosphate binders are added if phosphate stays high. Proteinuria is treated with an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker. Hypertension in cats is treated first with amlodipine, and in dogs often with an ACE inhibitor or ARB plus amlodipine. Treat dehydration, hypokalaemia (common in cats), nausea, anaemia and poor appetite as they arise. Hyperthyroidism in cats raises glomerular filtration and can hide CKD until the thyroid is treated.
Feline lower urinary tract disease (dysuria, pollakiuria, haematuria, periuria) in cats under about ten years is most often feline idiopathic cystitis, a stress-linked disorder; bacterial infection is uncommon in young cats. Management is multimodal environmental modification, more water intake (wet food), analgesia and stress reduction. A male cat that strains without producing urine is an emergency (urethral obstruction). In dogs, struvite stones are usually induced by urease-producing bacterial infection, often staphylococci, and are dissolved with a dissolution diet plus antimicrobials; in cats struvite is usually sterile and dissolves on diet alone. Calcium oxalate stones cannot be dissolved and are removed surgically, by voiding urohydropropulsion if small, or by lithotripsy. Urate stones occur in Dalmatians and in dogs with portosystemic shunts; cystine stones in dogs with inherited cystinuria. Stone type must be confirmed by quantitative analysis. Following ISCAID guidance, sporadic bacterial cystitis is treated for three to five days, while subclinical bacteriuria usually needs no treatment. Urethral sphincter mechanism incompetence causes leaking in spayed bitches, especially large breeds, and responds to phenylpropanolamine or oestriol.
Canine diabetes resembles human type 1: loss of beta cells, permanent insulin dependence, and cataracts in most dogs within a year. Feline diabetes resembles human type 2: insulin resistance (obesity, inactivity, glucocorticoids, progestogens, acromegaly) and glucotoxicity, with a real chance of remission if good glycaemic control and a low-carbohydrate, high-protein diet are achieved early. Signs are polyuria, polydipsia, polyphagia and weight loss; cats may develop a plantigrade stance from diabetic neuropathy. Stress hyperglycaemia is marked in cats, so diagnosis needs persistent hyperglycaemia with glucosuria, and a raised fructosamine reflects the previous one to three weeks.
Treatment is insulin with consistent meals, exercise and monitoring. The AAHA diabetes guidelines give typical starting doses of about 0.25 U/kg every 12 hours of an intermediate-acting insulin for dogs and 1 U per cat every 12 hours for cats — confirm against the product label and your national formulary. Insulin concentration must match the syringe (U-40 with U-40 syringes, U-100 with U-100) or the patient receives the wrong dose. Glucose curves, continuous glucose monitors, fructosamine and above all the owner's report of thirst and weight guide adjustment; hypoglycaemia is the most dangerous complication, and owners are taught to rub sugar syrup on the gums and seek help. Oral SGLT2 inhibitors are now licensed for cats in some countries, only for newly diagnosed cats that are otherwise well and not on insulin, because of the risk of euglycaemic ketoacidosis. Diabetic ketoacidosis is treated with fluids first, then regular insulin, with close attention to potassium and phosphate, which fall as insulin drives them into cells.
Hyperadrenocorticism (Cushing's syndrome) is a disease of middle-aged and older dogs. About 80–85% of natural cases are pituitary-dependent and the rest are functional adrenal tumours; iatrogenic disease comes from glucocorticoid treatment. Signs are polyuria, polydipsia, polyphagia, panting, pot belly, bilateral symmetrical alopecia, thin skin and calcinosis cutis. Typical laboratory findings are raised ALP, a stress leucogram, dilute urine and proteinuria. Test only dogs with compatible signs: the low-dose dexamethasone suppression test is the preferred screening test; the ACTH stimulation test is less sensitive but is the test for iatrogenic disease and for monitoring; a normal urine cortisol:creatinine ratio makes the disease unlikely. Endogenous ACTH, the high-dose test and ultrasound help separate pituitary from adrenal causes. Trilostane, which blocks 3-beta-hydroxysteroid dehydrogenase, is the usual medical treatment; mitotane and adrenalectomy are alternatives.
Hypoadrenocorticism (Addison's disease) affects young to middle-aged dogs, more often females and breeds such as the Standard Poodle, Portuguese Water Dog and Nova Scotia Duck Tolling Retriever. It waxes and wanes and mimics gastrointestinal and kidney disease. A sick dog without a stress leucogram (normal or high lymphocytes and eosinophils) should raise suspicion. Hyponatraemia and hyperkalaemia with a Na:K ratio below about 27 are typical, but atypical cases have normal electrolytes. A basal cortisol above about 2 µg/dL (55 nmol/L) makes the disease very unlikely; the ACTH stimulation test confirms it. The crisis is treated with 0.9% saline and dexamethasone (which does not cross-react with the cortisol assay), then lifelong glucocorticoid and mineralocorticoid replacement.
Hyperthyroidism is the common endocrine disease of older cats, usually from benign adenomatous hyperplasia; carcinoma is rare. Signs are weight loss despite a good appetite, polyuria, hyperactivity, vomiting, tachycardia and a palpable thyroid nodule. A raised total T4 confirms it; in a cat with suggestive signs and a high-normal total T4, a free T4 by equilibrium dialysis helps. Options are antithyroid drugs (methimazole or its prodrug carbimazole), radioiodine (131I), which is curative and the treatment of choice where available, surgical thyroidectomy, and an iodine-restricted diet. Check renal function before and after control, because treatment unmasks CKD.
Hypothyroidism is a disease of middle-aged dogs, from lymphocytic thyroiditis or idiopathic atrophy: lethargy, weight gain, non-pruritic alopecia, recurrent pyoderma and hypercholesterolaemia. Total T4 alone is not enough, because non-thyroidal illness and drugs (glucocorticoids, phenobarbital, sulfonamides) lower it; combine a low T4 or free T4 with a high TSH. Treatment is levothyroxine, monitored by a post-pill T4 about four to six hours after dosing. Hypercalcaemia in dogs is most often from cancer (lymphoma and apocrine gland anal sac adenocarcinoma via PTH-related protein), then primary hyperparathyroidism, hypoadrenocorticism, vitamin D toxicosis and kidney disease; in cats, idiopathic hypercalcaemia is common.
Myxomatous mitral valve disease is the commonest heart disease of dogs, especially small breeds and the Cavalier King Charles Spaniel. It presents first as a left apical systolic murmur. The ACVIM consensus stages it: A at risk, B1 murmur without significant heart enlargement, B2 murmur with left atrial and ventricular enlargement meeting set criteria (for example a left atrium to aorta ratio of 1.6 or more on echocardiography), C current or past congestive heart failure, and D failure refractory to standard treatment. In stage B2, pimobendan delays the onset of heart failure, as shown by the EPIC trial. Stage C is treated with furosemide, pimobendan, an ACE inhibitor and spironolactone. Owners count the sleeping respiratory rate at home: a rate persistently above about 30 breaths per minute suggests pulmonary oedema. Dilated cardiomyopathy affects large breeds, notably the Dobermann, where ventricular arrhythmias and sudden death may precede failure, so Holter monitoring is part of screening. The Boxer has arrhythmogenic right ventricular cardiomyopathy. Congenital defects include patent ductus arteriosus (a continuous machinery murmur at the left base; corrected by occlusion), pulmonic stenosis (brachycephalic and terrier breeds) and subaortic stenosis (large breeds such as the Newfoundland and Boxer).
Hypertrophic cardiomyopathy is the commonest heart disease of cats. Many affected cats have no murmur and many cats with murmurs have normal hearts, so echocardiography or NT-proBNP testing is needed. Cats with heart failure present with tachypnoea from pulmonary oedema or pleural effusion and rarely cough. Aortic thromboembolism causes sudden hind-limb paralysis with cold, pale, pulseless limbs and great pain; clopidogrel was superior to aspirin in preventing recurrence (the FAT CAT trial).
Breathing pattern localises disease. Stertor and stridor, with inspiratory effort, suggest upper-airway obstruction; expiratory effort and wheeze suggest lower airways; short, shallow, rapid breaths with muffled sounds suggest pleural space disease. Brachycephalic obstructive airway syndrome combines stenotic nares, an elongated and thickened soft palate, everted laryngeal saccules and a hypoplastic trachea; heat and stress cause crises, and early surgery widens the airway. Tracheal collapse causes a honking cough in small breeds. Laryngeal paralysis in older large dogs, often part of a generalised neuropathy, causes inspiratory stridor and heat intolerance. Canine infectious respiratory disease complex (kennel cough) involves Bordetella, parainfluenza, adenovirus and other agents, spreads where dogs gather and is usually self-limiting. Feline upper respiratory disease is caused mainly by feline herpesvirus-1 and calicivirus, with Chlamydia felis and Bordetella. Feline lower airway disease (asthma) causes cough and expiratory effort with airway eosinophilia; it is treated with glucocorticoids, systemic or inhaled, and bronchodilators in a crisis. Pleural effusion in cats most often comes from heart failure, pyothorax, neoplasia (including mediastinal lymphoma) or feline infectious peritonitis; thoracocentesis is both diagnostic and treatment.
Every lump deserves a needle. Fine-needle aspiration cytology separates inflammation from neoplasia and often identifies round-cell tumours (mast cell tumour, lymphoma, histiocytoma, plasmacytoma, transmissible venereal tumour) on the day. Biopsy gives the histological diagnosis and grade. Staging defines spread: regional lymph node aspirates, thoracic radiographs or CT, and abdominal ultrasound, recorded using TNM or the WHO scheme for that tumour. The aim of veterinary chemotherapy is good quality of life, so doses are lower than in human medicine and serious toxicity is uncommon; the neutrophil nadir usually comes about a week after most myelosuppressive drugs. Cytotoxic drugs must be handled with protective equipment and closed-system devices, and owners taught how to handle excreta in the days after treatment. Pain control and nutrition are part of every cancer plan, and palliative care is a legitimate goal.
Mast cell tumours are among the commonest skin tumours of dogs. They release histamine and heparin when handled (Darier's sign), so antihistamines are given before surgery. Behaviour depends on grade (the Patnaik three-tier and Kiupel two-tier systems), margins, stage and markers such as c-KIT mutation; treatment is wide excision, with radiation, chemotherapy or a tyrosine kinase inhibitor for high-grade or non-resectable disease. Multicentric lymphoma presents as generalised painless lymphadenopathy; T-cell lymphoma may cause hypercalcaemia. Multi-agent CHOP-based protocols induce remission in most dogs, with median survival commonly reported around a year; giving prednisolone before diagnosis and staging can reduce later response and should be avoided.
Appendicular osteosarcoma affects large and giant breeds at the metaphysis, classically distal radius, proximal humerus, distal femur and proximal tibia ('away from the elbow, towards the knee'). Most dogs already have lung micrometastases at diagnosis, so amputation alone is palliative and adjuvant chemotherapy extends survival. Haemangiosarcoma arises in spleen, right atrium, liver and skin, most often in German Shepherds and Golden Retrievers, and presents as collapse from haemoabdomen or pericardial effusion; not every bleeding splenic mass is malignant, so staging guides the owner's decision. Anal sac adenocarcinoma can cause hypercalcaemia and spreads to sublumbar lymph nodes, so a rectal examination belongs in every hypercalcaemia work-up. Canine mammary tumours are about half malignant in most studies, and spaying before the first oestrus greatly reduces risk. Feline mammary tumours are mostly malignant carcinomas, and early spaying also reduces risk. In cats, squamous cell carcinoma of the pinnae and nasal planum follows sun exposure in white cats; oral squamous cell carcinoma has a poor prognosis; lymphoma is the commonest haematopoietic tumour, now more often alimentary in older FeLV-negative cats; injection-site sarcoma needs wide, planned first surgery. Transmissible venereal tumour, spread by mating and contact in free-roaming dogs, responds very well to vincristine. Dogs with the ABCB1 mutation need reduced doses of some cytotoxic drugs, including vincristine and doxorubicin.
Behaviour problems are a leading reason dogs and cats are relinquished or euthanased, and many are normal behaviours in the wrong place or expressions of fear, anxiety and stress. The sensitive period for socialisation runs from about 3 to 12–14 weeks in puppies and about 2 to 7 weeks in kittens; animals exposed gently to people, handling, other animals and noises in that window become more resilient adults. Puppy classes run with sensible hygiene are advised before the vaccine course ends. Veterinary behaviour bodies advise against punishment and aversive tools, which increase fear and aggression; problems are treated with management, reward-based training, desensitisation and counter-conditioning, and medication when anxiety prevents learning.
Aggression is described by its context (fear, resource guarding, pain, inter-dog, redirected) and escalates through the ladder of body language: lip-licking, looking away, freezing, growling, snapping, biting. A punished growl removes the warning, not the fear. Separation-related problems cause vocalising, destruction and elimination when the dog is alone; clomipramine and fluoxetine are licensed for separation anxiety in some countries, always alongside behaviour modification, and serotonergic drugs must not be combined carelessly because of serotonin syndrome. Rule out medical causes first: pain, endocrine disease and neurological disease change behaviour. In cats, house soiling is investigated as urinary disease, litter aversion, location aversion or urine marking; guidelines suggest one litter tray per cat plus one, in quiet, separate places, cleaned daily. Low-stress handling and cat-friendly clinic standards reduce fear at visits, and pre-visit medication such as gabapentin is used for anxious animals.
AAHA's life-stage guidance defines a senior dog or cat as one in the last quarter of its predicted lifespan, which depends on breed and size. Seniors are examined at least twice a year with weight, body and muscle condition, blood pressure, dental examination, haematology, biochemistry, urinalysis and total T4 in cats. Periodontal disease is the commonest disease of adult dogs and cats; it needs a general anaesthetic, full-mouth dental radiographs and cleaning above and below the gum line, and anaesthesia-free cleaning is not advised. Tooth resorption is common and painful in cats.
Osteoarthritis is common and under-recognised, particularly in cats, which show it by not jumping, poor grooming and litter-box accidents rather than lameness. Validated owner questionnaires and pain scales help. Management is multimodal: weight control, controlled exercise and physiotherapy, environmental changes, NSAIDs used within label with renal and hepatic monitoring, anti-nerve growth factor monoclonal antibodies in dogs and cats, and adjuncts such as gabapentin or amantadine. Canine cognitive dysfunction presents as disorientation, changed social interaction, sleep-wake changes, house-soiling, altered activity and anxiety; diets enriched with antioxidants and medium-chain triglycerides, environmental enrichment, and in some countries selegiline are used.
Quality-of-life assessment gives owners a structured way to decide: scales ask about pain, appetite, hydration, hygiene, happiness, mobility and whether good days still outnumber bad. Palliative and hospice care can keep an animal comfortable for a time, but the vet must say plainly when suffering can no longer be controlled. Euthanasia is a medical procedure and a moment the family will remember. Plan it with the owner in advance: place, presence, sedation and aftercare. Guidelines such as those of the AVMA recommend sedation before the euthanasia injection, usually an overdose of pentobarbital given intravenously; intracardiac or intraperitoneal routes are acceptable only in an unconscious or deeply anaesthetised animal (intraperitoneal also in some small patients). Confirm death by absent heartbeat and breathing and loss of corneal reflex. Pentobarbital remains in the carcass and has poisoned wildlife and dogs that ate buried or discarded animals, so disposal follows local law. Grief is real; a follow-up call or card is part of care.
Triage assesses the major body systems in seconds: airway and breathing, circulation (heart rate, pulse quality, mucous membrane colour, capillary refill time), and neurological status. Shock is inadequate oxygen delivery to tissues, classed as hypovolaemic, distributive (sepsis, anaphylaxis), cardiogenic or obstructive (GDV, pericardial tamponade). Dogs in hypovolaemic shock are tachycardic; cats often show bradycardia, hypothermia and hypotension together. Lactate helps grade perfusion and track response. Hypovolaemic shock is treated with isotonic crystalloid boluses, commonly 10–20 mL/kg in dogs and 5–10 mL/kg in cats over 15–20 minutes, reassessing after each — confirm against the product label and your national formulary; cardiogenic shock is not treated with fluids. Dehydration is separate from shock: the deficit in litres equals body weight in kg times the percentage dehydration as a decimal, replaced over hours together with maintenance and ongoing losses.
Cardiopulmonary resuscitation follows the RECOVER guidelines: chest compressions at 100–120 per minute, compressing one-third to one-half of chest width, in two-minute cycles without interruption, intubation and ventilation at about 10 breaths per minute, ECG assessment between cycles, and low-dose adrenaline (epinephrine) around 0.01 mg/kg IV every other cycle — confirm against the product label and your national formulary. Ventricular fibrillation needs electrical defibrillation. Status epilepticus is treated with a benzodiazepine by the intravenous, intranasal or rectal route, then a longer-acting anticonvulsant; check glucose and calcium, and consider toxins.
Gastric dilatation-volvulus strikes large, deep-chested dogs: unproductive retching, a distended abdomen and shock. A right lateral radiograph shows the compartmentalised, displaced pylorus. Treat shock, decompress the stomach by orogastric tube or trocarisation, and operate to reposition the stomach and perform a gastropexy; ventricular arrhythmias are common afterwards. Prophylactic gastropexy is offered for high-risk breeds. Urethral obstruction in male cats causes hyperkalaemia with bradycardia and ECG changes (tall T waves, absent P waves); calcium gluconate protects the heart within minutes without lowering potassium, insulin with dextrose shifts potassium into cells, and the obstruction is relieved once the cat is stable. Pyometra appears in intact bitches weeks after oestrus, under progesterone dominance, with polyuria, polydipsia, lethargy and, if the cervix is open, vaginal discharge; E. coli is the usual organism, and stabilisation followed by ovariohysterectomy is the standard treatment.
Poisoning is common. Induce vomiting only within a useful time, in an alert patient, and never after caustics or hydrocarbons; apomorphine is used in dogs and an alpha-2 agonist in cats. Xylitol causes hypoglycaemia in dogs above about 0.1 g/kg and liver failure above about 0.5 g/kg. Chocolate (theobromine and caffeine) causes vomiting and restlessness at about 20 mg/kg methylxanthine, cardiac signs at about 40–50 mg/kg and seizures at about 60 mg/kg; dark and baking chocolate contain the most. Grapes and raisins cause kidney injury in dogs with no safe dose established. Anticoagulant rodenticides prolong the prothrombin time first and are treated with vitamin K1 for weeks. Ethylene glycol is treated with fomepizole or ethanol within hours. Paracetamol causes methaemoglobinaemia in cats, treated with acetylcysteine; permethrin causes tremors and seizures in cats. Heatstroke, commonest in brachycephalic and obese dogs, is treated by rapid cooling with room-temperature water and air flow, stopping at about 39.5 °C to avoid rebound hypothermia, then watching for coagulopathy, kidney injury and gut damage.
Learn a fixed routine for the first puppy and kitten visit (examination for congenital defects, vaccination, deworming, diet, socialisation, identification) and be able to write a vaccination and parasite plan for your own country from the WSAVA and ESCCAP, CAPC or TroCCAP guidelines. For each body system, learn one full case: the itchy dog, the vomiting cat, the drinking old dog, the thin hyperthyroid cat, the blocked tom. Practise the calculations until they are routine: RER and ration, fluid deficit, drug volume from mg/kg and concentration, insulin syringe matching, xylitol and chocolate doses per kg. Know the zoonoses you must explain to owners.
At five years you are running consultations alone and deciding how far to investigate within a family's budget. Use staged work-ups: the dermatology order (parasites, infection, allergy), IRIS staging with blood pressure and UPC before prescribing, a screening test only when the signs fit, and a sleeping respiratory rate at home for every heart patient. Keep an antimicrobial policy that follows ISCAID and national guidance and audit it. Build confidence in triage, CPR, GDV and the blocked cat. Offer a planned euthanasia and follow-up, and refer early when a case needs imaging, endoscopy, radioiodine or chemotherapy you cannot give.
With twenty-five years' experience you set the practice's standards: vaccination protocols matched to local disease, not to habit; parasite advice for local vectors; senior-care programmes that find kidney disease, hypertension, osteoarthritis and dental disease early; cat-friendly and low-stress handling. You mentor new graduates through their first euthanasias and difficult conversations, review morbidity and mortality cases, run clinical audit (surgical site infection, antimicrobial use, anaesthetic deaths), and decide which new tests and drugs earn a place. You also judge breeding and conformation welfare issues and speak for the profession locally.
A researcher with long experience asks what the guidelines still rest on weak evidence for: duration of immunity by vaccine and region, the causes of feline idiopathic cystitis and feline CKD, early biomarkers such as SDMA in populations outside Europe and North America, the diet and dilated cardiomyopathy question, genotype-phenotype links for inherited disease, and comparative oncology where dogs model human cancer. Good work here needs prospective cohorts in first-opinion practice, validated owner-reported outcomes, and trials designed with welfare and cost in mind, including in low-income countries where rabies and vector-borne diseases dominate.
This manual gives principles, standard classifications and the few doses that are standard teaching values; almost every other dose is left to the label and national formulary, because approvals and doses differ by country. Reference intervals are not tabulated, since they differ between laboratories. It does not cover neurology (seizure work-up beyond emergency care, intervertebral disc disease), ophthalmology, orthopaedics, haematology and immune-mediated disease, infectious diseases such as FIP, FIV, FeLV, leptospirosis and distemper in depth (see the preventive medicine and virology subjects), anaesthesia, surgery, or exotic pets. Regional diseases (tick paralysis, snake envenomation, tropical vector-borne infections) are named but not detailed. Where evidence is contested, such as neutering age in large-breed dogs or diet-associated DCM, the manual says so rather than taking a side.
Original practice questions written to the syllabus and pattern of the exams named in each question's examTags. They are not past papers and do not reproduce any board's questions.
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