When is the most fertile time for a dog contained by grill?

does it differ for certain dogs or is it all kinda the same? because it is approaching day 16 and she still is bleeding. is she still able to get prego?
Yes she maybe fertile for up to a few weeks after she have stoped bleeding.

please have her spayed!
A dog goes into fry (aka estrus) for 3 weeks. During this time period days 11-15 are the most fertile. That is the time in which they are most successful in breeding. Yes she can receive pregnant when bleeding. That is the only time she can get pregnant I think. It does not differ for different breeds. It is adjectives the same. The only thing that differs is the time within which they come into heat. It only comes twice a year. She is almost at the winding up of her cycle since there are about 21 days in adjectives. Don't breed her, as I see you are not yet qualified for this task. People who just "want to breed their dog for no reason" are the idea many dogs die in shelters each time. I know you don't want to become a part of that.
Answers:    generally days 12-14-16 sometimes on to 18 day of heat are most fertile..
You should consider your pet to be "in season" for 21 days: 7 days coming into heat, 7 days in fry, 7 days going out. Though conception is most likely during the middle 7 days, Mother Nature doesn't always follow the rules. Confine your pet for the entire 3 weeks.

If you do not know the answer to that question, what do you think you are doing breeding to start with?

If you are wanting to breed your dog, which is how your question reads, than you should already own the kind of knowledge you need prior to breeding. Just because a dog is within heat, does not mean it should be bred. There are standards set for every breed for a reason.to produce the best possible dog for that breed. Also, masses dog breeds have lots of health problems that should be considered long before anyone breeds, including me.
If you be asking the question because you wanted to know how soon you could get your dog spayed, I apologize, but to be precise not how your question is worded.
A dog should be a minimum of 2 years old, prior to breeding. You just asked what the pane for conception was. What was I to think but that you are planning on breeding.

Since she is still contained by heat, it is possible. It varies from dog to dog. It would be best to confine her as much as possible to avoid an unplanned breeding.
At day 16 its at the end of estrus. A couple more days and your dog shouldnt know how to get pregnant. Then you can have her spayed if that's what you want.
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