Yes. A cat can have kittens from different fathers in the same litter.
Yes, a female no longer goes into heat if they are pregnant.
Not common, but it is possible.
No. Only a male can impregnate a female. No female mammal of any species can get another female pregnant. For mammals that have a "heat" cycle, being in "heat" is required for pregnancy by a male. If such a mammal (a dog for instance) is not in heat or doesn't have a male partner, pregnancy is not possible.
Female cats should not go in heat when they're pregnant because it may harm the fetus.
Yes, a female dog is able to get pregnant whenever she is in heat, though I would wait another year before breeding her again if you have already bred her since some consider it cruel to breed dogs repeatedly without a break.
after they go into heat.
no they do not it dose not matter
No, a dog must be in heat to mate successfully. Otherwise she will not get pregnant.
it means if she is able to get pregnant
my female jack russel has not been on heat since november, why is this/
Cats are notorius for having false pregnacies.
Yes but it has a better chance halfway through heat