Field peas make an excellent feed for swine, according to Hans Stein, a swine nutritionist and researcher at South DakotaStateUniversity’s Department of Animal and Range Sciences. The university’s researchers have conducted 11 experiments over the past five years using field peas in swine diets.

Selling for about $3 a bushel, field peas can make an economical feed even for producers who don’t grow them, says Stein.

“We’ve found that all the amino acids are digested pretty much to the same degree as they are in soybean meal,” he notes. “The energy concentration in field peas is similar to what you find in corn, and the phosphorus is digested far better than in corn and soybean meal.”

South Dakota researchers also tested inclusion rates. “Initially we went up to 36 percent in diets for grow/finish pigs without seeing any problems,” says Stein. “We had performance that was absolutely similar to what we found with a corn/soybean meal diet.”

A separate experiment increased the inclusion rate to 60 percent field peas, then lowered it to 48 percent and finally to 36 percent as pigs grew and their amino acid requirements dropped. Pigs performed as well as on a traditional control diet.

That experiment also involved South Dakota meat scientists, who looked at carcass quality and found no negative effects from the field-pea diet. Consumer panel palatability tests showed no difference compared to other pork products. 

There are a few points to consider when using field peas in swine diets.

As a rule, field peas will substitute two-thirds of the corn and one-third of soybean meal in a grow/finish diet. Therefore, if you include 36 percent field peas, you can remove 24 percent corn and 12 percent soybean meal from the diet.

Stein adds that it’s important to keep an eye on amino acids, since the profile is somewhat different from soybean meal. There is more lysine in the protein from field peas, but there’s less methionine and threonine. Producers can remove some of the lysine from the diet, then add methionine and threonine when they balance the amino acids in the ration.

Because of the increased phosphorus digestibility, producers can remove some of the diet’s monocalcium phosphate or dicalcium phosphate. There will be less phosphorus excreted from pigs on the field-pea diet compared to a corn/soybean meal diet.

Stein adds that if producers add microbial phytase, they could completely remove the inorganic phosphorus from the diet, for a formulation cost savings.