URBANA, Ill. — Oilseed meals are commonly fed to pigs and
poultry as sources of protein. The concentration and digestibility of amino
acids in oilseed meals has been studied, but these ingredients supply other
nutrients in the diet, as well.
Now researchers at the University of Illinois are providing
a more complete picture of the nutritional value of oilseed meals.
A team led by Hans Stein, a U of I animal sciences
professor, evaluated canola seeds, canola meal, cottonseed meal, sunflower seeds
and two types of sunflower meal. The researchers conducted two experiments with
In the first, they determined the digestible and
metabolizable energy of each ingredient, and in the second, they determined the
standardized total tract digestibility of phosphorus with and without the
addition of microbial phytase.
“From these results, we conclude that it is possible to
include a number of different oilseed products in diets fed to pigs to meet the
requirements for digestible phosphorus and energy,” Stein said.
“The current data provide feed formulators, nutritionists
and swine producers with the data needed to include different oilseed products
in diets fed to pigs. Which ingredients are most economical to include in diets
depend on local availability and cost.”
Stein’s team found that the concentration of digestible
energy in sunflower seeds at 6,105 kilocalorie per kilogram of dry matter and
canola seeds at 5,375 kcal/kg DM was greater than that in soybean meal at 4,518
kcal/kg DM or corn at 4,040 kcal/kg DM.
Canola meal, sunflower meal, dehulled sunflower meal and
cottonseed meal contained less digestible energy — 3,652, 3,238, 3,095 and 3,016
kcal/kg DM, respectively — than soybean meal or corn.
Metabolizable energy values followed the same pattern: 5,739
kcal/kg DM in sunflower seeds; 5,098 kcal/kg in canola seeds DM; 4,035 kcal/kg
DM in soybean meal; 3,942 kcal/kg DM in corn; 3,306 kcal/kg DM in canola meal;
2,998 kcal/kg DM in sunflower meal; 2,860 kcal/kg DM in dehulled sunflower meal;
and 2,700 kcal/kg DM in cottonseed meal.
With no phytase added to the diets, the standardized total
tract digestibility of phosphorus ranged from as little as 37.4 percent in
sunflower meal to 62 percent in soybean meal. Phosphorus digestibility in
sunflower seeds at 51.7 percent and canola meal at 58 percent was not different
from that in soybean meal, but the value for all other ingredients was less than
in soybean meal.
The standardized total tract digestibility of phosphorus in
all ingredients improved when phytase was added to the diets, ranging from 54.9
percent in dehulled sunflower meal to 74.6 percent in canola meal and 78 percent
in soybean meal.
“If phytase is added to the diets, the digestibility of
phosphorus in canola seeds, canola meal and sunflower seeds is not different
from the digestibility in soybean meal, but the digestibility of phosphorus in
the other ingredients is less than in soybean meal,” Stein explained.
The study, “Energy concentration and phosphorus
digestibility in canola, cottonseed, and sunflower products fed to growing
pigs,” recently was published in the Canadian Journal of Animal Science.
Co-authors are Diego Rodríguez and Rommel Sulabo, both
former members of the Stein Monogastric Nutrition lab, and current Ph.D.
candidate Caroline González-Vega.