Dog twins?

Can puppies be twins?

Yes, dog twins do exist, but it's hard to tell unless you are watching the birth and see them sharing the birth "sac". Sheep and cows which usually have one baby per pregnancy, can also have twins, my brother in law lost some of his calves this past winter because they were twins an therefor small and wearer than their single birth counter parts. I have seen many double yolked eggs which if fertilized would be twins(if they could survive being egg mates). Twins is not just a human occurrence, it is just not as readily noticed in the canine world as dogs generally have more than one baby per pregnancy.

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Interesting link: http://www.ashgi.org/color/twins.htm