Chihuahua
| Size at withers | 15–23 cm |
|---|---|
| Weight range | 1.5–3 kg |
| Life expectancy | 12–20 years |
| Size class | Toy (< 10 kg) |
| Normal resting vitals | Heart rate 90–140 bpm · Respiration 15–30/min · Temperature 38.3–39.2 °C |
| Coat | Smooth or long coat |
| Temperament | Devoted to one person; can be nervous with strangers |
| Common health issues | Patellar luxation; tracheal collapse; hydrocephalus; hypoglycaemia; dental disease; heart murmurs |
| Exercise needs | Low — 20–30 min/day |
| Climate & housing suitability | Excellent for apartments; may struggle in cold conditions and chilly winter mornings. |
| Owner notes | Long lifespan means senior care matters. Dental care from puppyhood is essential. |
Origin and purpose
Toy (AKC). Origin: Mexico.
Long lifespan means senior care matters. Dental care from puppyhood is essential.
What a breed was built to do explains most of what it will do in your home. A dog selected for hundreds of years to run, guard, herd, or hunt does not stop wanting to because it now lives in an apartment — the drive is the breed, and the owner's job is to give it somewhere to go.
Temperament and training
Stated temperament: Devoted to one person; can be nervous with strangers
Reward-based training from the day the puppy arrives, with the socialisation window (roughly three to sixteen weeks) treated as the priority it is — what happens in those weeks shapes the adult dog more than anything you do later. Short, frequent, positive sessions. See Parts IV and IX.
Conditions this breed is predisposed to
Hydrocephalus
Mitral valve disease
Patellar luxation
Periodontal disease
Tracheal collapse
Health screening — what to test, and when
| Screen for | Test | When |
|---|---|---|
| Hydrocephalus | Imaging (ultrasound through an open fontanelle, or CT/MRI) | In any toy-breed puppy with a domed skull or slow learning |
| Mitral valve disease | Cardiac auscultation; echocardiography once a murmur is heard | Auscultation at every annual visit; annually from 5 years in small breeds |
| Patellar luxation | Patellar palpation by a vet | At each annual examination from 12 months |
| Periodontal disease | Oral examination; dental radiographs under anaesthesia | Annually from 2 years — earlier and more often in toy breeds |
Every dog, every breed: an annual health examination (twice yearly from seven years), body-condition scoring at each visit, dental assessment, year-round parasite control, and the core vaccinations.
For breeders — test before you mate
- Hydrocephalus — Imaging (ultrasound through an open fontanelle, or CT/MRI)
- Mitral valve disease — Cardiac auscultation; echocardiography once a murmur is heard
- Patellar luxation — Patellar palpation by a vet
Feeding
Small stomachs, fast metabolisms. Feed a diet formulated for small breeds, split across three or four meals a day as a puppy and two as an adult; toy puppies can become dangerously hypoglycaemic if a meal is missed. Portions are tiny, which means treats and table scraps overwhelm the daily allowance startlingly fast — a single biscuit can be a meaningful share of a 4 kg dog's intake. Dental disease is near-universal in small breeds, so ask your vet about diet texture and dental care from the start.
Exercise and enrichment
Stated requirement: Low — 20–30 min/day
Modest exercise needs, but 'low exercise' is not 'no exercise' — this dog still needs daily walks and enrichment, and is prone to obesity if it does not get them.
Coat and grooming
Smooth or long coat. Weekly brush. Needs warmth in winter; feels the cold badly.
Climate and living conditions
Stated suitability: Excellent for apartments; may struggle in cold conditions and chilly winter mornings.
Ageing and senior care
Life expectancy: 12–20 years. This dog is a senior from around 9–10 years, at which point wellness examinations should move to twice a year and senior blood and urine screening begins. Small dogs age slowly and often live into their mid-teens. Dental disease and heart-valve disease are the two things that most often shorten a small dog's life, and both are catchable early. Senior care →
Before you take one home
- Ask the breeder for the health-test results listed above — for BOTH parents, on paper, before you pay a deposit. A breeder who has done the tests will be proud to show you; one who deflects, or who tells you the tests are unnecessary in this line, is telling you what you need to know.
- Consider adoption. Shelters and rescues have dogs of every kind, including purebreds, and the local native or landrace dog is often healthier, better adapted to its climate, and more in need of a home than almost anything you can buy. See Part XII.
