HDTV (high definition television) HDTV (high definition television) is a television display technology that provides picture quality similar to 35 mm. movies with sound quality similar to that of today's compact disc. Some television stations have begun transmitting HDTV broadcasts to users on a limited number of channels.
Heat usually lasts between 2-4 weeks. Early in the cycle, a female dog may not be receptive to male dogs, although some are receptive through the entire cycle. It can be shorter or longer and youâll know the cycle is over when all her vulva returns to its normal size and thereâs no more bleeding or discharge.
1 Metestrus (or Diestrus): period after estrus or mating. 2  Length: 60-90 days. 3  If pregnant, pregnancy lasts between 60-64 days in the dog. 4  Anestrus: period of inactivity (sexual and hormonal) between estrus phases. On average, dogs have two cycles a year. 2  The estrus cycle lasts on average 12-21 days, but maybe be as short as a few days to four weeks. 3  The estrus period length varies widely between breeds and individual dogs. 4  The length of a cycle varies widely, even for dogs of the same breed.