A Shih Tzu (UK: , US: ; Chinese: 西施犬; pinyin: Xī Shī quǎn literally 'Xi Shi dog', also spelled Shittsu) is a toy dog breed, weighing from 4 to 7.25 kilograms (9–16 lb) when fully grown. The breed was developed in China. Hypothyroidism occurs when the thyroid gland malfunctions and stops producing a hormone responsible for proper metabolism. This malfunction is commonly attributed to immune system problems. It usually affects middle-aged dogs and is seen in all breeds. Symptoms include hair loss, weight gain, muscle loss, and lethargy. This disease is usually diagnosed through blood tests. It can be effectively treated with drug therapy. The UK Kennel Club survey puts the median lifespan of a Shih Tzu at 13 years and 2 months, with most living 10 to 16 years. The oldest living Shih Tzu was one named Smokey from Florida, who lived to be 23 years old.
living 10 to 16 years. 4 to 7.25 kilograms (9–16 lb)|10 to 16 years.
living 10 to 16 years. 4 to 7.25 kilograms (9–16 lb)|10 to 16 years.