Heat?

Question
I have 2 chihuahuas M/F both are 1 1/2. Their 1 st sex was about when they were 9 mos. She never become pregnant. Now  since sept. 18th 2007 they have been having sex. day1=1x, day2=0x day3=2x, day4=2x, day5=3x, so far day6=1x...is it normal to have sex this often? My male is the one that get so exicited. He usually sleeps with us but now he can't cause they only thing we will be hearing is him crying and wanted sex! It drives me crazy. Her 1st period was on Aug. 2006. Can she get pregnant without another period? What can we do to calm the male down? Or we can't? Just let them do it? will it hurt anything?

Answer
Hello Nai:

If your dogs are mating then your female is in estrus, the fertile portion of her heat cycle. Dogs don't have periods in the way women do -- with dogs a heat cycle occurs on average every 6 months (lasts a total of approx. 21 days on average) & is when they are able to breed in order to procreate. Your male will continue to breed with her until she's no longer in estrus, which generally lasts about 7 to 10 days. Once she's no longer in estrus she won't allow him to continue mating. A male will mate as frequently as he desires & is able while the female is in estrus so his behavior is perfectly normal. Most males are totally consumed during this time so again, his behavior is normal for these circumstances. It's very strongly possible their mating will result in a pregnancy unless there is an unknown reproductive health problem. There is really nothing you can do to calm down your male -- once she's out of estrus she'll stop giving off the scent that is instinctively causing his behavior, although it tends to taper off rather than stop immediately. However, it would be better to not let them continue to breed so frequently & I would suggest either crating one or the other of them or keeping one in a separate room until she's out of estrus. I know this may be extremely difficult since he's likely to be very vocal about his opinion on being separated from her. The only way you can prevent this from happening in the future is to have him neutered and preferably her spayed if you don't plan to breed them again.
Please let me know if you have any additional questions.