I've been lurking here for several years, but since I do have exp. in cattle/pigs farming, I just want to give some advise
I'm from Europe (Belgium), so I don't know how the situation is US or elsewhere but, why don't you pick a dual type of breed that is locally kept by farmers?
I would do so because then I won't have to keep a bull around when I want to have calves, but just go to a local farmer for it (less expensive then keeping a bull around). Next to that, you will be able to profit from the farmers selection of his bull (out of his many bullcavles) and get the best genetic advantages (not to mention, easy access to the same breed you are keeping and genetic diversity).
Also, there are lots of dual breeds, but you should define what you want out of it. Mostly Beef, or mostly Milk.. Most dual breeds do have a tendency to be better at one then the other anyway.
Do you have a busy/good job now, which defines how much time do you want to dedicate to it? Keeping cattle for beef takes a lot less daily effort/routine then keeping milk-cattle. (not to mention the equipment and keeping it clean and well tended). Generally speaking dairy cattle are easier to handle, more friendly, then beef cattle as they have been selected for that trait generation after generation. No farmer puts up with an unruly milkcow twice a day.. Those are kinda send to the slaughterhouse pretty fast.
A beef-cow that is unruly will be tolerated more as they don't require daily handeling (to some degree).
The site is in dutch:
http://www.zuivelonline.nl/?PageID=713For Milk I would probably pick:
Holstein roodbont
or
Mrij (maas-rijn-ijssel) -> good duel breed, best for milk though
For meat:
Belgisch witblauw -> also know as Belgian Blue, or 'Monster cow". Probably most productive beef-breed ever (converting kgs of feed to kgs of meat).
In light of PO
I wouldn't recommend them as they require caesarean in 90% of the cases to give birth. For the rest they are a very good choice. Not aggresive (at least not as limosin or charolais).
Cattle breeding is very intensive in Belgium, and so the belgian blue breed works for us. As prob. not in US, where ranching/feedlots are used (and less care goes into each animal seperatly which they do need -> prob. prone to more injuries otherwise).
So I would then prob. pick
"Mrij" (maas-rijn-ijssel) -> good duel breed, best for milk though or a cross between them and "Verbeterd roodbont"
-> mostly because in small-scale, I would keep the cows & heifers and raise the bull-calves (but slaughter them before the get 2yrs). The breed is easy to handle, and I don't want the trouble of any old bulls around. (i've already seen to much of their pointy ends anyway)
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