URBANA, Ill. — Hydrolyzed feather meal is a co-product of
the poultry processing industry that can be used as a protein source in swine.
A lack of published data on the digestibility of energy and
nutrients in feather meal fed to pigs spurred researchers at the University of
Illinois and Auburn University to give producers more information about the
nutritional value of the feed ingredient.
Hans Stein, a U of I animal sciences researcher, and Lee
Chiba, a professor animal nutrition at Auburn, collaborated to determine amino
acid and phosphorus digestibility and the concentration of digestible and
metabolizable energy in hydrolyzed feather meal from four different processing
The processing of hydrolyzed feather meal is not
standardized, which means that feather meal processed in different plants may
vary in nutritional value. Because feather meal may contain coagulated poultry
blood, each source was included in the experiment both without and with added
Results of the research indicated that the digestibility of
crude protein and every amino acid was different among the four sources if no
blood was added.
The addition of blood to feather meal had inconsistent
effects on the digestibility of amino acids. Digestibility of lysine increased
with the addition of blood in two of the sources of feather meal, but not in the
other two sources.
However, adding blood reduced the digestibility of
isoleucine, leucine, methionine, valine and the average of all indispensable
amino acids in two sources of feather meal, but had no effect in the other two
Stein said that the differences in amino acid digestibility
might be due to differences in processing.
“Processing conditions such as steam pressure and time of
hydrolysis can affect the quality and digestibility of protein and amino acids,”
he explained. “It is also possible that differences in the timing of blood
addition, before or after hydrolysis of the feathers, have an effect on amino
Other results indicated that there was a tendency for
phosphorus digestibility to differ among the four feather meal sources, but in
all cases digestibility was greater than 89 percent for feather meal without
For all sources, phosphorus digestibility in feather meal
with added blood was less than that in meal with no blood added, with
digestibility in one source reduced to as little as 50.2 percent.
The concentration of metabolizable energy ranged from 4,206
to 5,474 kcal per kg DM with no consistent response to the addition of blood.
However, there were significant differences among the four sources of feather
meal. These values are greater than values previously published for hydrolyzed
“It’s important for producers to consider the source of
feather meal and whether or not it has added blood when they’re using it in
swine diets. That way they can accurately assess its nutritional value,” Stein
“These results indicate that regardless of source or
addition of blood, feather meal contains more digestible and metabolizable
energy than has been demonstrated in the past.”
The paper, “Amino acid and phosphorus digestibility and
concentration of digestible and metabolizable energy in hydrolyzed feather meal
fed to growing pigs,” was published in a recent edition of the Journal of Animal Science.
It was coauthored with Stein, Chiba, Rommel Sulabo of the
University of the Philippines at Los Baños, Ferdinando Almeida of U of I, Sean
Brotzge of Auburn and Robert Payne of Evonik-Degussa Corp.