Large breed dogs can go into heat at six months of age, but may take as long as ten months.
The typical heat cycle last for three weeks or twenty one days.
The first stage is called the proestrus stage and last from 4 to 9 days. During this time you will see a bloody discharge.
The second stage is called the estrus stage and last from 4 to 13 days. During this stage the discharge will be more yellowish in color. This is the prime time for mating. She will allow any and all males to approach her and will do what is called "flagging". Flagging is moving her tail up and to one side to allow the male to mount her.
A dogs gestation period last from 58 to 65 days with 63 days being the average length of time from a successful mating.
A week or so before she is due she will become restless and start to look for a secluded place in the home. At this time you should provide her with a whelping box placed in a quite area of the house. Place some cloth or paper material in the box. She will rip this material apart in the whelping box to creat herself a nest to deliver her pups. Make sure the box is large enough for her to move around in and the sides are high enough to keep the pups inside.
Her body temperature will drop to 100deg or below twenty four hours before she will deliver her pups.
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