This can vary from one dog to the next. Typically, the heat cycle lasts around two to three weeks. The female's vulva will swell and then bleed for several days. Mating is typically done after being in heat for a good 10 days. Some females have what is called a silent heat. This occurs when a dog does not show the typical signs of being in heat but can still get pregnant. Be careful if your dog is in heat and you do not wish her to be bred.

Canine heat cycle occurs 2 times a year,and lasts for 3-4 weeks. They bleed for a week, cease for a week during their fertile period, then bleed for the last week. If you think your dog is pregnant, gestation is 63 days from time of breeding.

A female goes into heat about twice a year. They may skip a heat cycle occasionally, but will seldom have an extra one. The cycle lasts 21 days in dogs. Cats will go into their first heat between 5-8 months. A cat will remain in heat until she is bred. Small breed dogs at about 6 months and medium breed dogs at 8 or 9 months.

The female dog comes into heat (estrus) about every six months, although very large breeds of dogs may cycle every 8-10 months. The heat period lasts about three weeks.

The dog's estrus cycle is divided up into several stages. The first stage, pro estrus, usually lasts about 9 days. During this time the female's vulva swells and a discharge may be noted, although the female will not be receptive to the male. The actual estrus stage, or 'standing heat', lasts 3-21 days with an average of 9 days and occurs at the end of pro estrus. During this time the female is receptive to the male and will continue to have vulvar swelling and discharge.

Cats reach puberty around six months of age. A female kitten's first heat cycle will last about four to eight days and if she is not spayed or mated, she may go into heat again in another two to three weeks. A female cat's ovaries do not release eggs until she has mated, so a sexual encounter nearly always results in pregnancy. Because a full-term pregnancy is only eight to nine weeks, a healthy female is capable of producing several litters of kittens in a year.

Dogs reach puberty around six months of age. Your female puppy's first heat cycle will last 21 to 22 days, and she will continue to go into heat on the average of every six months, usually in the late winter and summer.

Early Canid Domestication: The Farm Fox Experiment - Behavioral genetics and development may interact in domestication according to this article from American Scientist, March-April 1999. Inherited Activation-inactivation of the Star Gene in Foxes Its bearing on the problem of domestication. Journal of Heredity, 1981. Border collies exhibit a wide variety of looks related to a tradition of breeding almost exclusively for behavioral characteristics.

A female dog (called a "bitch") goes into heat around every six months if she is not spayed. It is only during this time that she is receptive to mating with a male. Signs indicating heat are an enlargement of the vulva and a discharge. After heat is over, the bitch will either be pregnant or be experiencing a false pregnancy.

Cats - Polyestrus, this means during the spring and fall they go in and out of heat every 1 ? 4 weeks. The winter and summer is a time when they usually don't go into heat.

Females go twice a year into heat. The cycle starts at about 6-9 months of age. Dogs may skip a heat occasionally, if their mental or physical condition is weak.

We prefer that clients "switch" units periodically. In fact every two weeks is best. In this manner the system is always looking clean and natural. There won't be split ends. Color corrections will need to be done occasionally but it's a very easy process. Hair is a very durable medium.

The age of onset of the heat cycle varies with the breed of dog. Small breeds tend to begin cycling sooner, as early as six months of age. Larger breeds begin later, sometimes not until 12-18 months of age. Heat cycles then occur approximately every six months and last approximately three weeks.

Cats come into heat seasonally. They cycle at approximately 21-day intervals during the spring, summer, and fall.

The heat cycle is the mating period for female animals. Cat's normally have their first heat cycle between 5 to 10 months of age with the average being 6 months. Dog's first heat cycle are normally between 6-12 months. Some females of larger breeds may not have their first cycle until they are 12-24 months of age. Remember the above information is general not all females follow these patterns. Consult with your veterinarian if your pet does not seem typical.

Early signs include a swollen vulva and a light red or bloody discharge. Often, a dog’s first heat may be "silent" and accompanied by no or minimal discharge. Male dogs are usually attracted to her, as well.