Fish Oil May Help Young Pigs

By David Elstein
March 18, 2003

Consuming fish such as salmon and tuna, which contain omega-3 fatty acids, appears to lower the risk of cholesterol and heart disease in humans. Now Agricultural Research Service scientists are finding that fish oil also can improve the health of swine.

ARS animal physiologist Jeff Carroll evaluated the use of omega-3 fatty acids in young, weaned pigs as a better means of developing their immune systems and thus helping the animals fight deadly diseases. At the ARS Animal Physiology Research Unit in Columbia, Mo., Carroll fed one group of 18-day-old pigs a traditional diet that included 7 percent corn oil. The other group received 7 percent menhaden fish oil, which--like tuna and salmon-- contains high levels of omega-3 fatty acids.

After 14 days of feeding, the pigs were immunologically challenged with an endotoxin. Tests showed that the pigs given the fish oil were eating more feed after the challenge and that the fish oil helped them better prepare to fight the toxin.

Carroll has performed other research using different concentrations of fish oil. Each study showed that the fish oil diet was better than the control diet at helping build up the pigs' immune systems. The omega-3 fatty acids are absorbed through the intestine and help the immune cells cope with disease.

In the United States, pigs usually get some antibiotics in their feed, but other countries may phase out this procedure. Adding fish oil should help U.S. producers if they are required to eliminate antibiotics in the pigs' diet. In addition, fish oil will probably be less expensive than antibiotics.

Carroll worked on his studies with collaborators from the University of Missouri as well as with scientists from China Agriculture University and the University of Tennessee.

ARS is the U.S. Department of Agriculture's chief scientific research agency.