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.
The signs of a cat in heat are very clear once you know what to look for. What Is Feline Estrus? Female cats that have not been spayed undergo reproductive hormonal changes in preparation for breeding. This process is called estrus, or heat, and typically begins around six months of age. In general, cats experience estrus twice a year in the spring and fall. They may enter heat repeatedly during each season. An unspayed female cat of breeding age is called a queen. When the queen goes into heat, she experiences specific bodily changes to indicate to males that she is receptive to breeding.