Pigs make the most of your leftovers

April 5, 2013 - As the world population grows, farmers may feed more people by giving biofuel and food co-products to pigs. These co-products include whey, bakery waste, and plant matter left over from biofuel production.

In a new paper for Animal Frontiers, researchers say pigs are ideally suited to convert these non human-edible feedstuffs into protein.

Feeding co-products to pigs could solve a few problems for the livestock and food industries. Feed costs can be more than 72 percent of the overall cost of raising a pig. If producers have access to cheaper co-products, the price of pork may decrease. Feeding co-products could also leave more grain available for human consumption.

In their paper, Dr. Ruurd Zijlstra and Eduardo Beltranena, explain that though co-products may be a cheaper, more sustainable option, co-products have their own challenges.

Transport is the first challenge. To keep prices down, it helps to have swine farms close to co-product processing plants.

Co-products also have more variation than unprocessed crops. The nutrients in a corncob may not survive co-product processing. Zijlstra and Beltranena cite studies showing that heat can damage protein and lysine in co-products. Some co-products, like dried distillers’ grain, can also be a source of dangerous mycotoxins.

Feeding co-products can also change pork quality. Some co-products have more oils and fiber than traditional feedstuffs. This difference means pigs fed some co-products may produce less meat and the fat in their meat may be softer. Zijlstra and Beltranena said scientists are looking at ways to move excess oils and fiber.

The researchers say that with further studies, animal scientists may be able to improve the quality of co-products.

“Behind every food product in the supermarket, there is a co-product,” they write. “The livestock industry is an ideal platform to convert these low-value co-products into high quality animal protein.”

As feed prices increase, that is good news for swine farmers.

The full paper is titled "Swine convert co-products from food and biofuel industries into animal protein for food." It can be read online at http://www.animalfrontiers.org/content/3/2/48.full

Media contact:

Madeline McCurry-Schmidt
American Society of Animal Science
217-689-2435 / madelinems@asas.org