In Sweden the populations is foundated a bit like in USA. A couple of Wildboar farms had some "escapings" many ears ago. How pure they were, no one really know, they looked pure.
In the rest of Europe I would say they are pure. But the size variates a lot. The biggest ones we see from Russia, Romania and Bulgaria.
For what we have seen the hogs in Sweden are similar in type to the ones that Marvin caught in Louisiana lately. Fast and quite strong hogs.
Big adult male boars in Russia hunters over there say are not realistic to hunt with catchdogs. They tried many years ago, but gave up, they got their dogs killed.
Here is a big male boar shot in Sweden last year by our friend Henrik:
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B & P
B & P