Biodiesel Magazine, ND
06-22-07
Researchers study glycerin as animal feed
by Anduin Kirkbride McElroy
Researchers at two universities are examining the feed value of glycerin. Monty
Kerley, professor of ruminant nutrition at the University of Missouri-Columbia, is
researching the effectiveness of glycerin as cattle feed. The six-month study,
which started in May, will determine the impact of glycerin on calves’ growth
performance and meat quality. Over a period of 160 to 180 days, 60 calves from
various breeds will consume differing percentages of glycerin in their diets: 0
percent, 5 percent, 10 percent or 20 percent.
Meanwhile, researchers at Iowa State University (ISU) and the USDA
Agricultural Research Service (ARS) are researching glycerin in swine and
poultry feed. Brian Kerr, an ARS research leader and collaborating associate
professor of animal science, recently concluded a nine-month metabolism study,
in which nursery and finishing pigs were given feed with glycerin levels of 5
percent, 10 percent or 20 percent. The study found that glycerin is readily used
by pigs. Preliminary data suggests glycerol has approximately 3,500 kilocalories
per kilogram, Kerr said. He is also finalizing the data on a four-month growth
study, in which 5 percent and 10 percent glycerin was fed to pigs from weaning
to market weight. Results showed equal growth performance between the
glycerin-supplemented diet and a more conventional corn/soy meal diet. Kerr’s
glycerin was provided by Ag Processing Inc. in Sergeant Bluff, Iowa. Next, Kerr
would like to see if biodiesel feedstocks affect the feed quality of the glycerol.
A poultry study conducted by Kristjan Bregendahl, assistant professor of poultry
nutrition at ISU, trialed four levels of crude glycerin: 0 percent, 5 percent, 10
percent and 15 percent. It found the energy was used with high efficiency by 48
laying hens with no adverse effects. Other studies at ISU are in the works to
further examine the use of crude glycerin in diets for nursery and finishing pigs,
sows, broilers, and laying hens.