Do female dogs or any female mammal have periods?

Question

m and my friends are aruging over this subject. I dont think they do but... can you tell me? :P thanks

Answer 1

No. A period is the shedding of the lining of the womb, which develops throughout the month in preparation for pregnancy (a fertilized egg embeds itself in this lining to begin its growth). If an egg is released and not fertilized, it and the womb lining are shed as they are no longer needed. In animals, if pregnancy does not occur the womb lining is simply absorbed back into the body.

Some people are confused by the bloody discharge seen in animals such as cats and dogs when they are in heat - this is not a period, as it happens when the animal is ready to conceive. As I said, a period occurs after a woman has been 'in heat' and not conceived.

Answer 2

yes dogs and all other mammals ovulate and thus have a period if they do not become pregnant, usually this occurs twice a year for dogs and about once a month for humans.

Answer 3

All female mammals have periodic reproductive cycles. However, in most mammals there is an estral cycle, not a menstrual cycle like ours.

When the female is in estrus ("in heat") her external genitals may be swollen (and may bleed because the area gets more blood flow than usual, as in dogs), but if she doesn't mate and/or become pregnant, there is no menstrual discharge. Instead, the lining of the uterus goes back to its "normal" or resting conditions.

The only mammals that have periods (i.e. menstrual cycles) are the great apes (us and our close relatives, orangutans, chimpanzees and gorillas). In our case, when there is no pregnancy, the hypertrophied inner layer of the uterus "disintegrates" originating the menstrual blood discharge.

Answer 4

Yes dogs do.  However it is not quite the same as ours.  Humans have a hidden ovulation or hidden estrus cycle.  What this means is that when a woman is on her period she does not typically ovulate.  Instead ovualtion typically occurs in between their periods. Typically on day 14 counting from the first day of bleeding.  With dogs and most other animals ovulation occurs during the periods of excretion of blood from the uterus.  This is a case of whether the mammal needs both parent to care for the young or not.  Animals in which the male helps care for the young are more likely to have a hidden estrus cycle.  The hidden estrus makes it less likely for the male to look for another receptive female since he has a potentially receptive one at home.

Not all mammals however have periods in which blood is excreted.  Hooved mammals and other small mammals typically do not.  The reason there is that these mammals are typically prey animals and it would be very bad for prey animals to leave a blood trail everywhere they go.

I mentioned the bleeding thing because that is what most of my students are talking about when they use the term period.  I hope no offense was taken (it obviously bothers some people).

And yes in most great apes the male plays an important role in taking care of the young.  The exception being the orangutang in which widespread food sources force a solitary life style.

Answer 5

Yes. All(maybe most) animals that are non monotreme and are mammals must shed their uterine lining if they do not get pregnant right after they ovulate.