De Blasioâs effort is intended to address the needs of people at a variety of socioeconomic levels, from the very-low-income (now defined as under $25,150 for a family of four) to the middle class (families of four with incomes of $67,000 to $138,000).
Typically, during the breeding season, a mare will have a 21-day estrous cycle (the interval from one ovulation to the next). This length will vary between mares and time of the year. The estrous cycle is divided into two periods, estrus and diestrus. Estrus (heat) is the period (usually 4 to 7 days) when the mare is receptive to the stallion. During this period, ovarian follicles grow and develop to between 20 and 50mm in diameter with ovulation occurring 24 to 48 hours before the end of the estrus. Thus, the mare is still showing heat when she ovulates.
I would never lutalyse a mare with a 20mm follicle however. All mares are different in the speed of maturation but in most cases, a 20mm follicle will not take longer than a week to mature. I have had a few odd cases where they will digress with severe changes of weather or a stressful event occurs with the mare.