Imagine improving average daily gain and feed efficiency, cutting backfat by 20 percent, improving the pig’s immune system and the health qualities of the pork you send to consumers. Would you believe you might do that with one ingredient?

Conjugated linoleic acid is showing potential in all those areas. That makes it a hot topic in swine nutrition today.

“It is the biggest thing since I don’t know when,” contends Frederick Parrish, an Iowa State University professor of animal and food science and human nutrition.

But it’s much too early to declare it a miracle. Not enough data exists to say when or how CLA ultimately may work in your operation.

“We’ve got lots of work to do,” Parrish admits. “But the results, so far, are so promising that we’ll certainly be starting more experiments.”

Early work at Iowa State shows CLA, when included at 1 percent of the grow/finish diet, increases average daily gain and improves feed efficiency while cutting market hog backfat levels by up to 20 percent. It may be the first compound to boost growth and immune status at the same time.

“We’re looking at 100 pigs, using 0.75 percent in the diet, to see where we get results,” Parrish reports. “Do we need it the entire life of a grow/finish pig or just for the last 50 pounds?”

Mark Cook, a University of Wisconsin professor, did one of the first CLA studies in pigs. It showed pigs fed CLA had 0.84 percent CLA in their fat while control pigs had only 0.1 percent CLA.

The benefit would come if pigs fed CLA retained it in lean tissue. In humans CLA is thought to be an anti-cancer compound that also helps clear clogged arteries. Safflower and sunflower supplements that contain CLA are on health-food store shelves.

But how much CLA from hog feed may remain in pork? Answering that is one goal in a current Iowa State study.

“We haven’t analyzed the tissue yet,” Parrish says. “Theoretically, monogastric animals will deposit CLA in fat and perhaps lean tissue. How much, we don’t know. Everything indicates it will lead to a more healthful product.”

CLA also affects fat consistency, making bellies firmer. Soft bellies are causing problems for packers. Parrish and Iowa State geneticist Lauren Christian will try CLA in stress-gene-carrier animals to see how it affects belly quality.

Tom Baas, another Iowa State animal scientist, plans to provide CLA to sows during gestation and lactation to try to
produce stronger, more disease-resistant piglets. “It may trigger an immune system response,” Parrish says.

Iowa State also is looking at CLA in poultry, beef and dairy cattle. Parrish expects useful data in about six months. More work continues at Purdue, Wisconsin and other universities and feed companies, as well as overseas.

If it sounds too good to be true, recall other hot ideas such as porcine somatotropin. That looked like the final solution to pork’s lean quest but has yet to enter the market. That doesn’t mean CLA won’t pan out. It appears to have too many possible advantages to ignore.

The best advice on CLA? Believe it when you see it ù but keep your eyes open for more research reports.