All Conditions

acute or chronic degenerative tear. Signs: hock hyperflexion. Surgical.

A dramatic and rapidly dangerous syndrome in which the gut lining leaks blood and fluid into the intestine. What makes it lethal is not the visible blood but the invisible fluid shift: a dog can go into shock within hours as its circulating volume drains into its own gut. Small breeds (Miniature Schnauzer, Yorkshire Terrier, Miniature Poodle, Maltese) are over-represented. The critical thing for an owner to know is that this looks superficially like 'a bad tummy' and is not — a dog with sudden bloody diarrhoea and lethargy needs to be seen the same hour, not the next morning. Aggressive intravenous fluid support is the mainstay of treatment and is what saves these dogs; the vet will also rule out parvovirus, poisoning, and intestinal obstruction, which can look identical at presentation.

Not a disease in itself but a sign with many causes, and one that owners can and should learn to spot: lift the lip and look at the gum colour. Anaemia means too few red blood cells, whether from blood loss (trauma, a bleeding tumour, heavy flea or hookworm burden — the last is a genuinely common cause in puppies and street dogs), destruction (immune-mediated disease, tick-borne infection such as babesiosis or ehrlichiosis), or failure to produce them (chronic kidney disease, bone-marrow disease). Because the causes range from trivial to fatal, and because a severely anaemic dog can decompensate suddenly, pale gums always warrant prompt veterinary assessment and blood work. The cause determines the treatment; treating the anaemia without finding the cause is not treatment.

impaction or abscess. Signs: scooting, licking. Manual expression or surgical management.

cancer of anal glands. Senior dogs. Signs: perianal mass, hypercalcemia. Surgical / oncological management.

bacterial tick-borne. Signs: fever, lameness.

congenital in Boxer, Newfoundland, Golden Retriever. Signs: exercise intolerance, sudden death. Cardiology screening in puppies of predisposed breeds.

food or gastric contents in airway. Signs: cough, fever, laboured breathing. EMERGENCY.

allergic skin disease. Golden Retriever, Labrador, terriers. Signs: chronic itch, self-trauma. Environmental, food, and flea sensitivities investigated.

A blood vessel inside the ear flap ruptures — almost always because the dog has been shaking its head or scratching hard at an itchy, infected ear — and the flap fills with blood like a cushion. It is a consequence, not a primary disease, and this is the point most often missed: draining the swelling without treating the ear infection or allergy that caused the head-shaking guarantees it returns. Long-eared breeds (Cocker Spaniel, Basset Hound, Labrador) and dogs with allergic or yeast-driven ear disease are typical. Left alone it will eventually resolve, but by scarring into a permanently thickened, crumpled 'cauliflower ear'. A vet drains or surgically manages the flap AND investigates the underlying ear disease — both, or neither is worth doing.

protozoal tick-borne. Signs: anaemia, jaundice. Anti-protozoal-class treatment.

swarm stings are dangerous. Signs: swelling, hives; systemic anaphylaxis if severe. Emergency response.

intact senior males. Signs: difficulty defecating, blood in urine. Neutering resolves.

Common wherever dogs meet dogs — territorial fights with community dogs are a routine cause in many places. A bite is a puncture that injects bacteria deep under the skin and then seals over, so the skin heals while infection builds beneath it; the abscess appears days later as a hot painful lump. Bites over the chest or abdomen are far more serious than they look, because a canine tooth can penetrate the body wall. All bite wounds warrant veterinary attention: they typically need clipping, exploration, flushing, sometimes a drain, and an antimicrobial class chosen by the vet. Rabies risk must be assessed for any bite from an unknown or unvaccinated dog (see the rabies entry and the zoonoses part) — this is a decision with human consequences, not just canine ones.

dietary, breed, and metabolic causes. Struvite, calcium oxalate, urate (Dalmatian). Signs: straining, blood in urine. Dietary or surgical management.

fungal. Uncommon in most regions; environmental exposure. Signs: respiratory, skin, ocular.

anatomical obstruction in flat-faced breeds (Pug, French Bulldog, Bulldog, Boxer). Signs: loud breathing, snoring, exercise intolerance, heat intolerance. Surgical options exist for severe cases. Heat management critical in hot climates.

bacterial. Zoonotic. Reproductive-tract disease.

vaccination prevention.

viral, multi-system. Signs: respiratory, gastrointestinal, and neurological in sequence. Prevention via vaccination. Endemic in free-roaming and street-dog populations.

highly contagious viral gastroenteritis. Signs: vomiting, bloody diarrhoea, lethargy in unvaccinated puppies. Endemic in many regions. EMERGENCY. Prevention via vaccination.

congenital or diabetic or senior. Signs: cloudy lens. Surgical options.

prolapse of the third eyelid gland. Cocker Spaniel, Bulldog, Beagle. Surgical correction.

small-breed senior condition. Signs: chronic cough. Anti-inflammatory medication class + weight control.

chronic liver inflammation. Doberman, Labrador, Cocker Spaniel. Signs: weight loss, anorexia, jaundice. Complex management.

the leading senior chronic condition. Signs: increased drinking / urination, weight loss, poor appetite. Staging via blood and urine tests; renal diet is central; management not curative.

chronic inflammation of nasal passages. Multiple causes; workup includes imaging, biopsy.

protozoal in puppies. Signs: diarrhoea.

senior dogs. Signs: disorientation, altered sleep, altered interactions. Dietary and environmental interventions.

dietary, parasitic, or stress. Signs: mucous or blood in stool, frequent urgent defecation.

An inherited malformation of the tissue layers at the back of the eye, present from birth and non-progressive in its mild form. It is common in the Rough and Smooth Collie, the Border Collie, the Shetland Sheepdog, and the Australian Shepherd. Most affected dogs are mildly affected and live normally, which is precisely the problem for breeding: a dog can carry and pass on the gene while appearing perfectly healthy. A small proportion develop retinal detachment or haemorrhage and lose sight. Diagnosis is by an ophthalmologist's examination of puppies at around six to eight weeks — the window matters, because the mild changes can become harder to see as the eye matures — and by DNA test. It is not treatable; it is avoidable, by testing before breeding.

'blue' or fawn coats. Doberman, Weimaraner. Signs: coat thinning in dilute-colour areas. Cosmetic management.

genuine behavioural pathology; not just 'a bad habit'. Behavioural + medication class treatment.

Present from birth and permanent. It is strongly linked to the genes that produce white coats, merle patterning, and blue eyes — which is why it appears in the Dalmatian, the Australian Cattle Dog, the Bull Terrier, merle herding breeds, and, in India, in the white Rajapalayam. Deafness may be in one ear (easily missed; the dog behaves almost normally) or both. It is diagnosed definitively by a BAER test, which measures the brain's electrical response to sound and can be done in a puppy. A deaf dog can live a full, happy life on hand signals and vibration cues, but it must never be off-lead near traffic and must be woken by touch on the body, gently and predictably, never by surprise. Because it is heritable, affected dogs and — for the merle-linked form — merle-to-merle matings are the breeder's responsibility to avoid.

brachycephalic breeds, trauma. Signs: squinting, tearing.

the most common orthopaedic surgical presentation. Signs: sudden hind-limb lameness. Weight and activity management, surgical options.

undescended testicle. Increased testicular cancer risk; surgical removal recommended.

protozoal. Signs: diarrhoea in puppies.

inherited amino-acid transport defect leading to bladder stones. Newfoundland, Bulldog. Dietary and medical management.

progressive spinal-cord degeneration in senior large breeds (German Shepherd, Boxer). Signs: hind-limb weakness progressing.

mite. Localised (puppy) usually self-limiting; generalised (adult) requires medication. Signs: hair loss, secondary skin infection.

insulin-dependent. Middle-aged females predominantly. Signs: increased drinking / urination, weight loss despite appetite. Lifelong management.

enlarged heart with reduced pumping. Most common in Doberman (leading breed cause of death), Boxer, Great Dane. Signs: weakness, syncope, breathing difficulty. Emergency indicator: sudden collapse.

extra eyelashes irritating cornea. Surgical or manual.

Cocker Spaniel, Shih Tzu, Lhasa Apso. Signs: thick discharge. Lifelong topical management.

difficult birth. Toy breeds and brachycephalic breeds predisposed. C-section often required.

low blood calcium in nursing dam. Small-breed predominantly. EMERGENCY.

eyelid rolls outward. Basset, Saint Bernard. Chronic care.

very common tick-borne disease in India. Signs: fever, lethargy, thrombocytopenia. Antibiotic-class management.

abnormal elbow joint development. Similar breed predisposition. Signs: forelimb lameness.

rare but catastrophic.

infection of the heart valves. Uncommon but serious. Signs: fever, lameness (from immune-complex arthritis), heart murmur.

eyelid rolls inward. Chow Chow, Shar-Pei, Bulldog. Surgical.

An inherited disorder in which intense, excited exercise causes the hind limbs to fail and the dog to collapse. It is classically a Labrador Retriever condition, and is also seen in the Chesapeake Bay Retriever, Curly-Coated Retriever, and some Spaniels. It typically first appears in young adults during the activity they love most — retrieving, field work, hard play. Episodes can be fatal, particularly in heat, which makes it a serious matter in hot climates specifically. A DNA test identifies affected dogs definitively, and is worth doing in any working-line retriever. Management is entirely about avoidance: recognise the trigger, stop the activity at the first wobble, cool the dog, and keep it out of the excitement-plus-heat combination that provokes it. Do not confuse it with heatstroke — but do treat any collapse in the heat as heatstroke until a vet says otherwise.

pancreas fails to secrete digestive enzymes. German Shepherd Dog predominantly. Signs: severe weight loss despite normal appetite, cow-pat faeces. Lifelong enzyme replacement.

sudden-death puppies in first 2 weeks. Multiple causes.

The kidney tubules fail to reabsorb the nutrients the body has already filtered, so glucose, amino acids, and electrolytes are lost in the urine. The classic clue is glucose in the urine of a dog whose blood glucose is entirely normal — which means it is sometimes misdiagnosed as diabetes, a mistake with serious consequences. It is inherited in the Basenji, where it is common enough that regular urine glucose monitoring is recommended for the life of the dog, and it can also be acquired. There is a DNA test for the Basenji form. It is managed, not cured, by replacing what is being lost under close veterinary supervision, and dogs can do well for years with committed monitoring.

connective-tissue cancer. Signs: subcutaneous mass.

hypersensitivity to flea saliva. Signs: hind-quarter dermatitis. Flea control is the intervention.

stomach twists on itself. Deep-chested large breeds (Great Dane, German Shepherd, Weimaraner, Standard Poodle). Signs: distended abdomen, unproductive retching, restlessness. TRUE EMERGENCY — survival tied to speed of surgical intervention. Prophylactic gastropexy commonly recommended.

protozoal. Signs: intermittent diarrhoea. Zoonotic risk.

early stage; reversible.

elevated intraocular pressure. Basset Hound, Cocker Spaniel, Beagle. Signs: red eye, cloudy cornea, pain. EMERGENCY.

inflammatory brain disease. Small-breed middle-aged females. Signs: neurological deficits. Immunosuppressive.

blood-vessel cancer, aggressive. Golden Retriever, German Shepherd. Often presents as sudden collapse from internal bleeding.

mosquito-borne. Endemic in many regions, especially warm and humid climates. Prevention via monthly chewable medication class (macrocyclic lactone) is standard of care. Signs: chronic cough, exercise intolerance.

The single most preventable canine emergency in hot climates, and the one most under-represented in Western references. Dogs shed heat almost entirely by panting, so high humidity — not just high temperature — is what kills: a hot, humid tropical afternoon can be lethal well below the temperature at which a dog from a temperate climate would be at risk. Brachycephalic breeds (Pug, Bulldog, Boxer, Shih Tzu), thick-coated northern breeds (Husky, Saint Bernard, German Shepherd), obese dogs, puppies, seniors, and any dog with laryngeal or airway disease are far more vulnerable. Classic triggers are a midday walk on hot tarmac, exercise or play in the sun, and being left in a parked car or on an unshaded balcony or terrace. Heatstroke is a true emergency: it damages the gut lining, kidneys, and clotting system, and a dog that appears to recover can deteriorate hours later. Begin cooling immediately with cool (not iced) water over the body while arranging transport, and get to a vet even if the dog seems to improve — the internal damage is not visible. Prevention is walking at dawn and dusk, unlimited shade and water, and never leaving a dog in a stationary vehicle.

fatty liver. Signs: anorexia, weight loss, jaundice. Aggressive nutritional support.

senior dogs. Signs: weight loss, abdominal mass.

protozoal, tick-transmitted (dog swallows infected tick). Signs: fever, gait abnormalities. Reported in India.

abnormal hip joint development. Large-breed predisposed (German Shepherd, Labrador, Golden Retriever, Rottweiler). Signs: bunny-hopping gait, exercise intolerance, difficulty rising. Weight management, physiotherapy, surgical options in severe cases.

A blood-sucking intestinal worm and, in warm, humid soils, a genuinely dangerous one — heavy burdens can bleed a puppy to death. Larvae are picked up from contaminated ground, or penetrate the skin directly (typically the feet and belly of a dog lying on infected soil), and can also pass to puppies in the milk. It is a leading cause of the severe anaemia seen in street and shelter puppies. Hookworm is zoonotic: larvae can penetrate human skin and cause an itching, migrating track, which is why children should not play barefoot where dogs defecate. Diagnosis is by faecal examination; treatment is an anthelmintic class the vet selects, with supportive care (including transfusion in severe cases), and prevention is routine deworming plus faeces removal.

sudden painful moist skin lesion. Trigger and treat.

Cerebrospinal fluid accumulates within the brain and raises the pressure inside the skull. It is most often congenital and is seen predominantly in the toy and brachycephalic breeds — Chihuahua, Pomeranian, Maltese, Yorkshire Terrier, Pug, Boston Terrier, English Bulldog — where a domed head is sometimes wrongly admired as a breed characteristic rather than recognised as a warning. Severity ranges from a dog that lives a near-normal life to one with severe neurological impairment. Diagnosis is by imaging. Management may be medical (a medication class that reduces fluid production, chosen by the vet) or surgical (a shunt). It is a reason to look carefully at the head shape of any toy-breed puppy before buying it, and a reason not to breed from affected animals.

excessive cortisol. Senior small breeds. Signs: increased drinking / urination, pot-belly, coat changes. Complex diagnosis.

Miniature Schnauzer predisposed. Dietary management.

young large-breed metabolic bone disease. Signs: pain in growing bones, fever.

insufficient cortisol. Standard Poodle, Portuguese Water Dog. Signs: episodic vomiting, weakness, sudden collapse. EMERGENCY in Addisonian crisis.

underactive thyroid. Middle-aged medium-large breeds (Labrador, Golden Retriever, Doberman). Signs: weight gain, coat thinning, lethargy, cold intolerance. Blood test diagnosis.

seizure disorder with no identifiable cause. Onset typically 1–5 years. Border Collie, Beagle, Labrador. Lifelong medication class (anticonvulsants) if frequent.

The immune system destroys the dog's own red blood cells, and the resulting anaemia can become life-threatening within days. It may arise on its own or be triggered by an underlying problem — in tick-endemic regions, tick-borne infection is a particularly important trigger, so the two are investigated together. Cocker Spaniel, Springer Spaniel, Poodle, and Old English Sheepdog are among the over-represented breeds, and middle-aged females are typical. Diagnosis rests on blood work; treatment is immunosuppression (a medication class the vet selects), supportive care, and sometimes transfusion. Mortality is significant and clotting complications are the main danger, so this is a condition to present for immediately rather than monitor at home. Pale gums in a suddenly weak dog are an emergency finding.

German Shepherd Dog characteristic. Signs: corneal opacification. Lifelong topical immunosuppressive.

The immune system destroys the platelets that make blood clot, so the dog bleeds spontaneously into the skin and mucous membranes. The tell-tale sign is petechiae — pinpoint red dots that, unlike a rash, do not blanch when pressed. As with IMHA, tick-borne disease is an important trigger in tick-endemic regions and is investigated at the same time. It can occur alongside IMHA. Diagnosis is by platelet count; management is immunosuppressive (class chosen by the vet) plus strict rest, because the risk is bleeding into the brain or gut. Any spontaneous bruising or bleeding in a dog is an immediate veterinary matter.

chronic. Signs: intermittent vomiting or diarrhoea. Diagnostic and dietary work-up.

pancreatic tumour secreting insulin. Signs: episodic hypoglycaemia, seizures. Surgical.

disc herniation. Dachshund, French Bulldog, Beagle. Signs: back pain, hind-limb weakness or paralysis. EMERGENCY if paralysis. Cage rest through surgery.

foreign body. Signs: repeated vomiting, reduced appetite, painful abdomen. EMERGENCY — surgical.

toy-breed puppies. Signs: weakness, collapse. Frequent feeding schedule.

bacterial and viral infection. Signs: dry hacking cough. Prevention via vaccination.

senior large breeds (Labrador). Signs: change in bark, exercise intolerance, breathing difficulty. Surgical options exist.

femoral head necrosis in small breeds (Toy, terriers). Signs: hind-limb lameness in a young dog. Surgical.

a real risk in some cities where leopards enter urban peripheries (Mumbai, Bengaluru, Nashik). Fatal outcomes possible.

zoonotic bacterial. Rat urine reservoir; peaks in warm, wet and monsoon seasons. Prevention via vaccination (regional serovar considerations).

the most-diagnosed haematological cancer in dogs. Golden Retriever, Boxer. Signs: enlarged lymph nodes. Chemotherapy class of treatment.

A single gene mutation that breaks the pump which normally keeps certain medication classes out of the brain. A dog carrying it can be poisoned by a perfectly normal dose of a perfectly normal drug — several antiparasitic classes, some anti-diarrhoeal, sedative, and chemotherapeutic agents among them. The affected classes are a matter for the veterinarian; the owner's job is simply to KNOW, and to tell every vet who treats the dog. It is common in the herding breeds — Collie, Border Collie, Australian Shepherd, Shetland Sheepdog, Old English Sheepdog, and their crosses — with the Rough Collie most affected of all. There is a cheap, definitive DNA test (a cheek swab), and it should be done once in the life of any herding-breed dog, ideally before it ever needs treating. This is one of the few entries in this encyclopedia where a single test, done once, can prevent a death.

misaligned bite. Congenital.

intact and late-spayed females. Signs: mammary lump. Early spay reduces risk.

skin cancer. Boxer, Boston Terrier, Golden Retriever. Signs: variable skin lump. Surgical excision.

immune-mediated inflammation of chewing muscles. Signs: inability to open mouth, muscle wasting. Immunosuppressive management.

mammary gland infection during lactation.

dilated non-functional oesophagus. Congenital or acquired. Signs: regurgitation (not vomiting). Elevated feeding management.

oral, ocular, cutaneous. Chow Chow, Standard Poodle. Signs: pigmented mass.

degenerative valve disease; most common in senior small breeds (Cavalier King Charles, Dachshund, Chihuahua). Signs: soft cough, exercise intolerance, murmur. Cardiology screening.

rhesus and bonnet macaques in parts of urban South Asia. Bite wounds and infections; rabies risk from monkey bite is low but not zero.

Fly larvae infest living tissue. It is a defining problem of the tropical monsoon and of hot humid regions generally, it is largely absent from Western texts, and it is a true emergency: maggots liberate enzymes that digest tissue, so a small neglected wound can become an extensive one within 48 hours, with systemic toxicity and death in advanced cases. Any moist, soiled, or neglected site attracts flies — a wound, a hot spot, a matted coat, faeces-soiled fur, an ear-tip fly-strike lesion, the umbilicus of a newborn puppy. Free-roaming and community dogs, long-coated dogs, and immobile or elderly dogs are most at risk. Do NOT attempt to treat it at home: the wound must be clipped, every larva removed, and the tissue debrided by a vet, with supportive care and an antiparasitic and antimicrobial class of the vet's choosing. Prevention is prompt attention to every wound in fly season, keeping the coat clean and dry, and daily checks of skin folds and hindquarters in monsoon.

senior dogs. Signs: unilateral nasal discharge, facial deformity. Radiation-therapy option.

fungal infection of nasal passages. Signs: chronic nasal discharge, epistaxis, sneezing. Difficult treatment.

collie-nose. UV-triggered. Signs: crusting on nose. Sun protection.

Pug, Yorkshire Terrier. Signs: seizures, circling. Poor prognosis.

protozoal. Signs: neurological in young dogs.

critical during fireworks and festival seasons. Desensitisation programme + medication class as short-term relief on high-risk days.

The most common preventable health problem in urban pet dogs, and the one most often mistaken for good health — in many places a round dog is still frequently read as a well-cared-for dog. Excess weight is not cosmetic: it measurably shortens life, and it worsens nearly everything else in this encyclopedia — it accelerates arthritis and hip and elbow dysplasia, strains the heart and airway, sharply raises heatstroke risk (a critical concern in hot climates), predisposes to diabetes and to cruciate ligament rupture, and raises anaesthetic risk. Common drivers are free-feeding, table scraps and other human food, biscuits and treats used as affection, unmeasured portions, and too little exercise. Assessment is by body condition score — a hands-on judgement of whether you can feel the ribs and see a waist — not by the number on a scale, which means nothing without a breed and frame to compare it to. Weight loss is achieved by measured portions of a diet the vet specifies, treats counted within the daily allowance, and a gradual increase in exercise; crash dieting is harmful. This is a condition owners control completely, which is precisely why it deserves a monograph rather than a footnote.

One of the most common serious poisonings in many regions, because the agents are everywhere: agricultural pesticides, household insecticide sprays and chalks, some older tick and flea preparations, and — the reason many cases present — deliberate poisoning of street dogs. Exposure can be by ingestion, by skin contact, or by inhalation. The toxin blocks the enzyme that switches nerve signals off, so everything fires at once: the classic picture is a dog drooling, urinating, defecating and tremoring with pinpoint pupils. This is an immediate emergency with a narrow window. Take the dog to a vet at once, and carry the product packaging if it is known — naming the agent changes what the vet can do. If the exposure was to the skin or coat, wash the dog thoroughly with mild detergent and lukewarm water while arranging transport, wearing gloves. Do not induce vomiting unless a vet instructs it. Specific antidotes and decontamination exist and are given by the vet; survival depends heavily on how quickly the dog reaches care.

cartilage-bone lesion. Large-breed puppies. Signs: lameness in a growing dog. Surgical correction.

bone cancer, aggressive. Large breeds (Rottweiler, Great Dane, Greyhound). Signs: limb swelling, lameness. Poor prognosis.

very common in drop-eared breeds (Cocker Spaniel, Basset Hound) and warm, humid climates. Signs: head shaking, scratching, odour. Regular ear cleaning; medication for acute episodes.

inflammation of the pancreas. Miniature Schnauzer, Cocker Spaniel, senior small breeds. Signs: vomiting, hunched posture, abdominal pain. Low-fat diet often long-term recommendation.

self-limiting bone inflammation in young dogs. German Shepherd Dog, Basset. Signs: shifting-leg lameness, self-resolves.

kneecap slips out of groove. Small breeds predominantly. Signs: skipping gait. Grade 1–4; surgical for higher grades.

congenital; failure of a foetal blood vessel to close. Signs: heart murmur in puppy, exercise intolerance. Surgical / interventional correction.

chronic draining tracts around anus. German Shepherd Dog predisposed. Immunosuppressive medication class.

fluid around the heart; often haemangiosarcoma-related in Golden Retrievers, German Shepherds. Signs: sudden weakness, abdominal distension. EMERGENCY.

the most-diagnosed condition overall in adult dogs. Signs: bad breath, tartar, gingival recession, loose teeth. Prevention: daily brushing; dental cleaning under GA every 1–3 years.

deep-tissue injury; quills continue to work inward. Emergency vet removal.

abnormal blood vessel bypassing liver. Small-breed puppy or congenital in Yorkshire Terrier, Maltese; also acquired in cirrhosis. Signs: stunted growth, neurological signs after meals.

genetic retinal degeneration. Many breeds. Signs: night blindness progressing to day blindness.

elevated pressure in pulmonary vasculature. Signs: exercise intolerance, syncope, cough. Complex management.

bacterial skin infection. Secondary to underlying allergy or immune issue. Signs: pustules, crusts.

pus in the uterus of intact females. Signs: increased drinking, discharge (open pyo) or nothing obvious (closed pyo). EMERGENCY — surgical.

zoonotic viral. Endemic in much of Asia and Africa (which carry the highest burden of human rabies deaths). Vaccination is legally required in many jurisdictions and non-negotiable ethically.

sudden vision loss. Emergency ophthalmology referral.

paroxysmal snorting; benign and self-limiting in most.

tick-borne. Zoonotic risk.

A leading cause of death and serious injury in free-roaming and community dogs, and a constant risk to owned dogs walked off-lead near traffic. The visible wound is rarely the problem: the killers are internal haemorrhage, a ruptured bladder, a diaphragmatic tear, chest bruising, and shock, all of which can be present in a dog that gets up and walks away. Every dog hit by a vehicle needs veterinary assessment even if it looks unharmed, and should be reassessed over the following 24–48 hours. Move the dog as a single unit on a board or blanket without twisting the spine, muzzle only if breathing is unobstructed (a frightened, painful dog will bite the person it loves), control obvious bleeding with direct pressure, and keep it warm and quiet in transit. Do not offer food or water. Prevention is unglamorous and effective: a lead on every road walk, a secured gate, and a collar with an identity tag.

The most common intestinal worm of dogs worldwide and near-universal in unwormed puppies. Puppies are typically infected from their mother — across the placenta before birth and through her milk after it — which is why worming starts in the first weeks of life and why worming the bitch is not sufficient. It matters beyond the dog: Toxocara is zoonotic, and eggs shed in faeces contaminate soil and public parks, where children can ingest them, with rare but serious consequences for the eyes and other organs. That makes routine worming and picking up faeces a public-health act, not only a courtesy. Diagnosis is by faecal examination; treatment is a routine anthelmintic class on a schedule the vet sets, and prevention is a lifelong deworming programme (see the parasite-control section).

bacterial. Zoonotic risk. Signs: diarrhoea.

contagious mite. Intense pruritus. Prescription topical treatment.

warm, arid and tropical regions especially. Signs: severe local pain, cardiac symptoms, autonomic storm. Emergency vet care.

autoimmune destruction of sebaceous glands. Poodle, Akita, Samoyed. Signs: dandruff, alopecia. Topical management.

see Part IV; medication class as adjunct to behavioural modification when severe.

Bulldog, Pug, Shar-Pei. Signs: odour, redness in folds. Regular cleaning.

Snakebite is a leading envenomation emergency in tropical and subtropical regions, and South Asia's burden is world-leading. In India, the 'Big Four' medically significant snakes: Russell's viper (Daboia russelii), common krait (Bungarus caeruleus), spectacled cobra (Naja naja), saw-scaled viper (Echis carinatus). Signs vary by venom type: haemorrhagic (viper) = swelling, bleeding; neurotoxic (krait, cobra) = weakness, difficulty breathing, ptosis. TRUE EMERGENCY. Antivenom class treatment at any equipped vet or human hospital.

Fluid-filled cavities form within the spinal cord, usually because the skull is too small for the brain it contains and the flow of cerebrospinal fluid is obstructed. It is painful — often severely so — and it is over-represented in the Cavalier King Charles Spaniel to a degree that has become a defining welfare issue for the breed, with the Griffon Bruxellois and other small brachycephalic toys also affected. The characteristic sign is a dog scratching at its neck, on one side, without touching it. Diagnosis requires MRI. Management is by medication classes that reduce fluid production and pain, chosen by the veterinarian, and sometimes surgery; it can rarely be cured. This is a condition that should be discussed frankly with any breeder of a Cavalier before purchase, and MRI-screened breeding stock is the only real answer to it.

Usually a trivial infection with one profoundly important exception. The common tapeworm (Dipylidium) is acquired by swallowing an infected flea during grooming, so a tapeworm diagnosis is really a flea diagnosis — treating the worm without treating the fleas guarantees its return. The exception is Echinococcus, the hydatid tapeworm, which is endemic in livestock-keeping regions, particularly where dogs have access to raw offal from sheep and goats. In Echinococcus the dog is only mildly affected, but humans who ingest the eggs can develop hydatid cysts in the liver or lungs — a serious, sometimes fatal human disease. This is the clearest reason in this encyclopedia not to feed dogs raw offal or allow them to scavenge slaughter waste, and to worm dogs in livestock-keeping areas on a schedule the vet sets. Handwashing after handling dogs matters.

intact senior males. Neutering is prevention.

A toxin produced by bacteria that grow in a deep, dirty, oxygen-poor wound — a puncture, a bite, a nail injury, or a fresh castration or umbilical wound. Dogs are considerably more resistant than horses or humans, so tetanus is uncommon, but in many regions the combination of soil contamination and untreated wounds makes it a genuine risk, and it is worth recognising. The signature is progressive, generalised muscle rigidity with a fixed facial expression, and spasms provoked by any stimulus. It is a critical-care emergency: affected dogs need intensive nursing in a dark, quiet room, wound management, muscle relaxation and antimicrobial classes chosen by the vet, and sometimes weeks of support, and many still die. Prevention is prompt, thorough cleaning of every deep or dirty wound — the same message as the myiasis and bite-wound entries.

Boxer, Beagle. Signs: neck mass, dysphonia.

Australia's Ixodes holocyclus is the classic, but ticks in other regions can occasionally cause similar rare presentations. Signs: progressive weakness from hindlimbs forward. Remove the tick.

Ehrlichiosis, Babesiosis, Anaplasmosis. Endemic in tropical and subtropical regions. Signs: fever, lethargy, joint pain, anaemia. Tick control is prevention.

Bufo species (Indian common toad, Duttaphrynus melanostictus). Signs: excessive salivation, oral pain. Rinse mouth thoroughly.

cracks and slab fractures from bones and hard chews. Signs: reluctance to chew, pain. Root canal or extraction.

protozoal. Zoonotic. Signs: variable.

floppy trachea in small breeds (Pomeranian, Chihuahua, Yorkshire Terrier). Signs: 'goose honk' cough. Weight management is a first-line intervention.

bladder. Scottish Terrier, Shetland Sheepdog. Signs: blood in urine, straining.

One of the most important tumours in warm regions with large free-roaming dog populations, and almost invisible in Western references, because it is a disease of free-breeding, free-roaming dog populations — which is to say, of most free-roaming dogs worldwide. TVT is extraordinary: the tumour cells themselves are the infectious agent, transmitted physically from dog to dog during mating (and, for the nasal and oral forms, by licking and sniffing). It is one of only a handful of known transmissible cancers in nature, and the cell line is thousands of years old. It presents as a fleshy, bleeding, cauliflower-like growth on the genitals of either sex; owners often notice blood dripping rather than the mass. It rarely spreads internally, and — importantly — it responds well to a chemotherapeutic protocol that a vet administers, with a high cure rate, so this is a diagnosis to act on rather than despair over. Any genital mass or unexplained genital bleeding should be seen promptly. Neutering and control of free-roaming breeding are what prevent it at population level, which ties this entry directly to Animal Birth Control programmes.

congenital right-heart valve malformation. Labrador Retriever predisposed. Signs: exercise intolerance, ascites.

sudden inability to close the jaw. Usually self-resolves.

sphincter mechanism incompetence. Medication class management.

common in females. Signs: increased frequency, straining, blood.

inflammation of the uveal tract. Multiple causes.

'idiopathic' or geriatric. Signs: sudden head tilt, circling, nystagmus. Often self-resolves.

pigment loss. Cosmetic; no health impact.

Lives in the large intestine and causes a stubborn, relapsing, mucus- and blood-streaked diarrhoea that is often mistaken for colitis or food intolerance and treated for months as such. Two things make it awkward: the eggs are shed intermittently, so a single negative faecal test does not rule it out, and the eggs are exceptionally tough and survive in soil for years, which means a contaminated yard reinfects the dog indefinitely. It is worth considering in any dog with chronic large-bowel signs that has not responded to the obvious. Treatment is an anthelmintic class chosen by the vet, usually repeated, alongside environmental control.

A risk in rural and agricultural areas. Significant trauma from tusks.

Doberman, Great Dane. Signs: wobbly gait, neck pain.

Northern breeds (Husky, Malamute). Signs: crusts around eyes / mouth. Zinc supplementation.

The most common inherited bleeding disorder of dogs: a deficiency of von Willebrand factor, a protein needed for platelets to plug a damaged vessel. Doberman Pinscher is the classic breed (a large proportion of the breed carries it), with Scottish Terrier, Shetland Sheepdog, German Shepherd, and Standard Poodle also affected. Most dogs live normally and the disease only announces itself as unexpected, hard-to-stop bleeding during a routine procedure — which is exactly why it matters: a DNA or blood test BEFORE elective surgery in an at-risk breed is the entire point. There is no cure; management is avoiding unnecessary surgery, testing before any that is necessary, and telling every vet who treats the dog. Breeders of affected breeds should test and select against it (see the breeding ethics part).