How to raise fat pigs?

Hello I am wondering how do you grow a pig to be particularly fat. When I harvest my pigs I want there to be large layers of backfat to use for lard and mixing with venison sausage.  Currently I have 2 Berkshire x wildboar pigs that are putting on weight good but I don't know if its just a matter of letting them grow out more or is there tricks to raising fat pigs?

I make a lot of wild game sausage and found I like to add 30% pork fat to the mix. I keep and eye out for unwanted potbelly pigs and they normally provide a good quantity of fat for my purposes.

Hi Marc;
There are certain breeds that have a higher amount of body fat than a "bacon" pig.
In your case I would limit their range and feed them lots of grain, plus all the apples and garden products you can get ahold of.

thomas rubino wrote:Hi Marc;
In your case I would limit their range and feed them lots of grain, plus all the apples and garden products you can get ahold of.

That is basically the formula I've been following, giving them tons of things trying to provide a wide variety of things.

We always fed our pigs an excess of corn towards the time when we butchered them. Surplus food adds fat, especially grains, also like the post above me; some breeds are better for fat production. I know the ones that I have raised were Durocs and Yorkshires(?). The durocs didn't seem to have as good a flavor and not as much fat. The Yorkshire pigs seem to have a gentler personality and are easier to raise, and the flavor of the meat was much better along with more fat.

Just to make it abundantly clear for anyone reading this post down the road. There are two "types" of pigs.

Lard pigs were breed to get fat and produce a lot of lard. They tend to be shorter bodied, less inclined to root as much, and the ones I've read about tend to be more docile... maybe because that uses fewer calories?

Bacon pigs were breed to produce more bacon. They are longer bodied, making room for more bacon. They generally have less fat on them, than a lard pig, but any animal can get fat. These tend to be much more active, much more inclined to root around and seem to have a wider range of personalities than the lard pigs (again that is just in reading, I do not have that extensive experience with pigs).

There is an interesting article on the Livestock Conservancy website about this. https://livestockconservancy.org/heritage-swine/historypigs/

From the research, a Heritage pig will get more fat than a modern production breed. And a heritage lard pig will get more fat than a heritage bacon pig.
Lard Example:  American Guinea Hog
Bacon Example: Tamworth

Specific to the OP's post... my friend google says Berkshires are classified as lard pigs. I would think the wild boar mix might offset that, as I would imagine wild boars will breed for speed and strength, not necessarily for fat content.

You dont need a special lard pig. Take a Berkshire and feed them longer.
A young animal produce meat. A older animal more fat.
Feed the pigs 4 months longer, than you earn more fat. Give them later more energie (corn or barley) and lower protein.
And take out the wildboar. It's eliminate your success.

as an update I raised these half Berkshire half wild boar pigs until they were 1 year old and harvested great amounts of both meat and fat off of them. the barrow had a back fat cap of over three inches. between the two pig2s I putup over 150 lbs of fat for venison sausages and 6 gallons of lard!