canine-medicine

name	canine-medicine
description	Canine-specific clinical medicine covering breed predispositions, common disease presentations, normal physiologic parameters, and species-specific diagnostic and treatment approaches for dogs.

Canine Medicine

Overview

Canine-specific clinical medicine covering breed predispositions, common disease presentations, normal physiologic parameters, and species-specific diagnostic and treatment approaches for dogs. Dogs are the most commonly treated veterinary species with the deepest evidence base, but significant breed variation means "canine medicine" is not monolithic.

When to Use

• Patient is a dog of any breed, age, or size
• User asks about canine-specific disease presentations, diagnostics, or treatments
• User asks about breed-specific considerations in dogs
• Keywords: dog, canine, puppy, breed, K9

Clinical Reference Values (Adult Dog)

Parameter	Normal Range
Temperature	100.5-102.5°F (38.1-39.2°C)
Heart rate	60-140 bpm (size-dependent: large dogs lower, small dogs higher)
Respiratory rate	10-30 bpm
CRT (capillary refill time)	< 2 seconds
Systolic blood pressure	110-160 mmHg
PCV	37-55%
Total protein	5.0-7.5 g/dL
Blood glucose	74-143 mg/dL
BUN	7-27 mg/dL
Creatinine	0.5-1.8 mg/dL (sighthounds: up to 2.2 mg/dL normal)

Key Canine-Specific Considerations

• Breed diversity creates enormous clinical variation. A 2 kg Chihuahua and a 70 kg Great Dane are the same species but have dramatically different disease profiles, drug dosing, anesthetic risk, and life expectancy (5-7 years for giant breeds vs. 14-16 years for small breeds).
• Sighthound normals differ: Greyhounds and related breeds have lower WBC, platelet counts, and T4, higher PCV (55-65%), and higher creatinine (up to 2.2 mg/dL). These are physiologic, not pathologic.
• MDR1 mutation: Primarily affects herding breeds (Collie, Australian Shepherd, Shetland Sheepdog, Old English Sheepdog, and crosses). Causes sensitivity to ivermectin (high dose), loperamide, acepromazine, and some chemotherapy agents. Test before prescribing P-glycoprotein substrates.
• Brachycephalic breeds (Bulldogs, Pugs, French Bulldogs): Brachycephalic obstructive airway syndrome (BOAS), higher anesthesia risk, corneal ulceration, spinal malformations, heat stroke susceptibility.
• Large/Giant breeds: Higher incidence of orthopedic disease (hip/elbow dysplasia, OCD), osteosarcoma, DCM, GDV. Shorter life expectancy. Prophylactic gastropexy may be recommended for GDV-prone breeds.

Common Canine Diseases (No Feline Equivalent)

• GDV (gastric dilatation-volvulus): Surgical emergency. Deep-chested breeds (Great Dane, German Shepherd, Standard Poodle, Weimaraner). Mortality 10-45% even with treatment.
• CCL rupture (cranial cruciate ligament): Most common orthopedic surgery in dogs. Breeds: Labrador, Rottweiler, Newfoundland. TPLO is gold standard surgical correction.
• Canine cognitive dysfunction (CCD): Age-related dementia. Prevalence >50% in dogs over 11 years. Disorientation, altered sleep cycles, loss of housetraining.
• Idiopathic epilepsy: Breed-dependent prevalence (Border Collie, Belgian Tervuren, Labrador, Golden Retriever). Onset typically 1-5 years. First-line: phenobarbital or levetiracetam.

Canine-Specific Diagnostics

Test	Purpose	Notes
4Dx SNAP	Heartworm + tick-borne disease (Ehrlichia, Anaplasma, Lyme)	Annual screening in endemic areas
cPLI / Spec cPL	Canine pancreatitis	More specific than lipase/amylase
NT-proBNP	Cardiac biomarker	Screening for occult heart disease
SDMA	Early renal disease	Rises before creatinine in CKD
Thyroxine (T4)	Hypothyroidism screening	Common in middle-aged large breeds
Cortisol (LDDS/ACTH stim)	Cushing's disease	Common in older small breeds

Drug Safety Notes

• Dogs tolerate acetaminophen (with caution, 10 mg/kg PO q12h) but cats cannot.
• Chocolate (theobromine) toxicity: dogs metabolize theobromine slowly (~17.5 hour half-life). Dose-dependent: mild GI at 20 mg/kg, cardiac at 40 mg/kg, seizures/death at 60+ mg/kg.
• Xylitol: Profoundly hypoglycemic in dogs (0.1 g/kg), hepatotoxic at higher doses.
• Grape/raisin toxicity: Idiosyncratic nephrotoxicity. No established safe dose. Treat all exposures as potentially lethal.
• NSAIDs: Carprofen, meloxicam, deracoxib, firocoxib all FDA-approved for canine use. Always check renal function and avoid concurrent corticosteroid use.

Workflow

1. Identify breed, age, sex, reproductive status, and weight.
2. Apply breed-specific disease predispositions to differential ranking.
3. Use canine-specific reference ranges for lab interpretation. Note sighthound exceptions.
4. Check MDR1 status for herding breeds before prescribing P-glycoprotein substrates.
5. Select canine-approved drugs at species-appropriate doses.
6. Consider size-category differences (toy, small, medium, large, giant) for drug dosing, anesthetic protocols, and disease risk.

Limitations

• Canine medicine is the best-evidenced area of veterinary medicine, but many conditions still lack RCT-level evidence.
• Mixed breed dogs may carry predispositions from any contributing breed. DNA testing (Embark, Wisdom Panel) can help but is not comprehensive.
• Regional disease prevalence varies significantly (heartworm, tick-borne diseases, Valley Fever, blastomycosis, leptospirosis).
• Breed-specific reference ranges are only well-established for sighthounds; other breeds may have uncharacterized normals.