A TSH test measures the amount of thyroid stimulating hormone (TSH) in your blood. TSH is produced by the pituitary gland and tells the thyroid gland to make and release the hormones thyroxine (T4) and triiodothyronine (T3). See also: 1  T3 test.  T4 test.
Best Answer: Female cats typically have their first heat around the age of six months, which usually lasts for 5 to 7 days. Cat's heat cycles are light dependent and they usually have heat cycles every 9 to 13 days from January through October, though some indoor cats exposed to constant light times will cycle all year. I advise unless you want kittens to keep her in at these times.
When does a female cat go into heat? Heat cycles can start as early as the fourth or fifth month of a kitten's life, but usually start around six months. Heat cycles will continue all her life until you spay her.â¦ A cat is usually in heat for a week or two, and will start again every two to three weeks. 2 people found this useful.