youngc1@gao.gov. American Samoa is a U.S. insular area that operates its customs and immigration programs according to its own laws and independent of the United States. As such, U.S. agencies, such as U.S. Customs and Border Protection, have no roles in operating the customs or immigration programs in American Samoa.
Quick Answer. A female dog goes into heat again between 4 and 6 months of having her puppies. The non-spayed dog goes into heat twice a year, and this is known as estrus. The estrus cycle lasts between 12 and 21 days but often varies between breeds and dog size.
How often does a female dog come into heat? Most dogs come into heat twice per year, or about every six months, although the interval can vary between breeds, and from dog to dog. Small breed dogs may cycle three times per year, while giant breed dogs may only cycle once every 12-18 months. When young dogs first begin to cycle, it is normal for their cycles to be somewhat irregular. It can take up to 2 years for a female dog to develop regular cycles. There is no season of the year which corresponds to a breeding season for domesticated dogs. How long does estrus last? Although this can vary with the individual dog, on average a dog will be 'in heat' for 2-3 weeks. The onset of estrus is characterized by swelling of the external vulva.