A 15-year collaborative research effort between the USDA's Agricultural Research Service and the University of Minnesota has identified how the quality of alternative fats and oils affects livestock productivity, providing new information to help livestock producers and feed manufacturers evaluate feed ingredients.

The review summarizes research examining the nutritional and economic value of adding fats and oils from plant and animal sources to livestock diets. These lipids are commonly used to provide energy and improve animal performance by supporting efficient conversion of feed into weight gain.

The research also examined recycled fats and oils from the food service industry, which are processed and incorporated into livestock feed. Reusing these materials helps reduce food waste, lower environmental impacts and improve resource efficiency.

Researchers found that heating fats and oils, particularly during frying, reduces their nutritional value through oxidation. As oils become degraded, they develop compounds that can interfere with animal metabolism and reduce growth performance, raising concerns among swine and poultry producers about the value of recycled fats and oils in feed.

The studies found that increasing levels of oxidized lipids reduced feed intake and growth by as much as 25% in pigs and up to 10% in broiler chickens. Researchers reported that animal performance declined as the level of oil degradation increased.

The review also found that measuring the concentration of oxidized compounds in heated oils, along with the amount of lipid already present in a diet, can help feed manufacturers compare formulations and better predict animal performance.

According to the researchers, the findings provide livestock producers, feed mill managers and farmers with a scientific basis for assessing the caloric and economic value of fats and oils used in feed. The information can help guide decisions on whether alternative lipid sources should be included in livestock diets based on established quality indicators.

The full study is available here.

Source: U.S. Department of Agriculture, "15 Years of Data Could be the Key Ingredient to Animal Feed"