Organic livestock production comes with challenges, two of which are the high costs of organic feed and bedding. Dr. Yuzhi Li, professor of organic swine production, University of Minnesota, explained how the university raises organic pigs and reviews several research projects designed to explore feed cost options.

The first consideration in organic pig production is sow feed and housing during the last trimester of gestation. At the university’s research center, organic pigs are housed in a gestation barn and moved to a farrowing house three days prior to their due date. Each sow has an individual box for farrowing, and sows have access to feed and water in a communal area.

“There are no gestation stalls, no farrowing crates, and pigs have access to the outdoors,” said Li. “Pigs are provided with fresh air and sunshine and housed on bedded floors. There are no antibiotics, no tail docking or ear notching.”

Castration of male pigs is allowed, and pigs are weaned at six weeks compared to three weeks for conventional pigs. They are provided with organic bedding and feed throughout all life stages.

“Organic pig production doesn’t necessarily require group farrowing,” said Li, “but a lot of farmers use it because it’s easy to manage. We wean pigs at six weeks of age by moving the sow out of the group. All the piglets of the same age are housed together.”

At eight weeks, pigs are moved to a hoop barn until they reach market weight of about 270 lbs.

Organic livestock production presents a unique business opportunity for farmers. There’s a premium for organic pigs – usually two to three times the conventional price. Organic pig production is suitable for small-scale family farms and provides an opportunity to connect with local buyers who are interested in specialty pork. The need for organic feed and bedding supports local organic crop production.

In addition to the need for organic feed and bedding, another challenge is dealing with internal parasites that can be spread via communal bedded floors. While sows have freedom to move, crushing of neonatal piglets is a problem. Li said pre-weaning mortality of 20% to 30% or higher isn’t unusual. The biggest obstacle is the high cost of production – especially bedding and feed.

Li explained a university study in which camelina byproducts were fed to pigs. “Camelina is an oilseed crop in the Brassica family,” she said, adding that producers can choose spring camelina or winter camelina. “We used winter camelina because it can be used as a cover crop.”

Camelina requires minimal fertilizer, suppresses weeds and is resistant to pests and diseases. Camelina oil is rich in omega-3 fatty acids, which makes it desirable for cooking, and it can also be used for aviation biofuel.

Cutting feed costs in organic pig production

Winter rye is a suitable substitute in an organic pig ration. This crop also provides straw and acts as a cover crop. Photo by Tom Kasper

“When camelina is grown for the oil product, the byproduct is camelina press cake,” said Li. “The camelina seed contains about 35% oil, and you cannot crush all the oil out, so 70% of the camelina seed will eventually become press cake. It’s rich in energy and protein and used in livestock feed.”

For the research trial, camelina was grown on organically certified land. The seed was harvested and pressed for oil. The remaining press cake was used in pigs’ diets.

The control diet for conventional pigs was corn/soybean meal; the organic treatment group was fed 10% press camelina cake. “The treatment group had reduced final weight – about 14 pounds less than the control pigs,” said Li. “The treatment group didn’t eat as much as the control group. Mortality was higher in the control group but not statistically significant.”

Replacing 10% camelina press cake to organic pigs reduced feed intake by 3% and weight gain by 6%. Reduced feed consumption was likely due to anti-nutritional factors in camelina including glucosinolates and erucic acid. Li said these issues can be addressed by crop breeding, oil extraction and fermentation. There was no increase in feed efficiency in the camelina group, and pork quality was the same in both groups.

In a previous camelina feeding trial, pigs were found to have enlarged livers so the ration for that study limited the amount of camelina. Li expects that this issue will resolve with crop breeding.

Another project involved growing winter hybrid rye, then using the grain as a feed ingredient and straw for bedding. “There are no anti-nutritional factors like in camelina press cake,” said Li. “Rye is a dual crop and can be grown for feed and bedding. Winter rye can also diversify crop rotations and suppresses weeds.”

The control group received a corn/soybean diet and pigs were bedded with wheat straw. The treatment pen had rye straw bedding, and 50% of the corn from control diet was substituted with rye.

Pig performance and bedding usage were measured, along with evaluation of carcass traits and overall pork quality. The study also included consumer taste testing. The rye group had no difference in carcass traits, dressing percentage, carcass length, backfat or chill loss. Pork quality as judged by a consumer panel in the rye group had a slightly lower toughness rating, but the score was well within normal.

The study showed pigs in the rye group cost $30 less to raise, although the net return was similar for both groups. However, if rye is homegrown, some of the corn in the ration is replaced with rye and rye straw used as bedding, savings are much greater.

Li estimated one acre of rye can replace 50% of corn for one pig and should provide enough bedding for 16 pigs in a good growing year.

“Replacing 50% of corn with hybrid rye does not negatively impact pig growth, pork quality or eating experience,” said Li. “Growing hybrid rye to feed and bed organic pigs is economically viable. Gain in net return depends on hybrid rye yield and corn prices.”

by Sally Colby