Above is a photo of a Berkshire sow with her 11 Mangalitsa-Berkshire piglets.
Below is a European Wild Boar (a sow) with her piglets:
The Mangalitsa is directly derived from the European Wild Boar - explaining the origin of the stripes on the Mangalitsa-Berkshire piglets.
Breeding a Mangalitsa boar to Berkshire sows allows us to produce a lot of crossbreed animals - because the sows multiply the boar's genetics. One boar and 20 sows produce a lot of crossbred piglets. Add a few more boars to breed the 50/50 females and you've got a lot of 3/4 Mangalitsa market hogs. That's what they do in Spain and Hungary.
To produce the hybrid pigs pictured at the top, we put Hans in with a harem of Berkshire sows (Franz, the other boar, is with the Mangalitsa sows). Although Hans is about half the weight of the Berkshire sows, when they are in heat, they'll stand in a hollow or on the downslope of a hill, allowing him to do his job.
This method - natural breeding - is quite archaic. The normal thing to do is AI, which, if you have the facilities, makes things go a lot smoother.