Slide 1
Hi, my name is Ferdinando Almeida. I am a Ph. D. student at the Hans 
Stein Monogastric Laboratory at the University of Illinois, and today 
I'm here to discuss about an experiment in which we determined the 
digestibility of amino acids in corn, corn co-products, and bakery meal 
fed to growing pigs.

Slide 2
Our outline for this presentation will be a short introduction followed 
by materials and methods, results, conclusions, and some implications of 
this research.

Slide 3
In the feed industry, there is a need to explore alternative feed 
sources because of the increasing costs of traditional feedstuffs. Many 
of these feedstuffs are byproducts of the corn milling and fermentation 
industries, or from other industries such as the baking and cereal 
industries.

Slide 4
When looking at the milling industry, we have two different processes. 
First, the dry milling, in which hominy feed is obtained as a byproduct 
of the corn grits production. Distillers dried grains with solubles, or 
DDGS, are also produced by the dry milling process. Second, we have the 
wet milling processes in which corn gluten meal, corn gluten feed, and 
corn germ meal are produced. Corn germ meal, however, can also be 
produced by the dry milling process, but the one we used in this 
experiment was produced by the wet milling process.

Slide 5
Let's now take a closer look at the wet milling process. In this 
process, corn is cleaned and steeped, and it may then undergo germ 
extraction, resulting in production of corn oil for human consumption or 
corn germ meal for animal feed. The cleaned and steeped corn may also 
undergo milling and washing to obtain bran and a bran-free product. The 
bran is further processed into corn gluten feed and used for animal 
feeding. The bran-free product undergoes centrifugation to separate 
gluten and starch. The gluten portion is processed into corn gluten meal 
and sold for animal feed.

Slide 6
Bakery meal, which is another alternative feed ingredient evaluated in 
this experiment, is produced by mixing, grinding, and drying a 
combination of available commodities such as wheat products, pasta, 
potato chip waste, cakes, and breakfast cereals.

Slide 7
There has been a considerable amount of research to determine both the 
apparent (or AID) and standardized (or SID) ileal amino acid 
digestibility in both corn and DDGS. However, limited research has been 
done to determine the AID and SID of amino acids in corn co-products and 
in bakery meal.

Slide 8
And that leads us to our objectives, which were to determine both AID 
and SID of amino acids in corn gluten meal, corn gluten feed, corn germ 
meal, bakery meal, hominy feed, and to compare these values with the 
values for the AID and SID of amino acids in corn and DDGS.

Slide 9
Now, looking at the materials and methods, let me first set up this 
graph. On the Y-axis, we have the nutritional composition of these 
ingredients in percentage, and for this first one we're looking at crude 
protein concentration. On the X-axis, we have our test ingredients. So 
starting from the left, we have corn, DDGS, bakery meal, corn gluten 
meal, corn gluten feed, corn germ meal, and hominy feed. And as we 
observe in this first graph, we can see that corn gluten meal is the one 
ingredient here that contains the greatest concentration of crude 
protein compared with 25% in DDGS, 23% in corn gluten feed, and also 25% 
in corn germ meal.

Slide 10
Now, looking at the NDF concentration, we observed that corn germ meal 
is the one that has the highest concentration of NDF at 49% versus 35% 
in DDGS and 31% in corn gluten feed.

Slide 11
For the starch concentration, corn is the one that contains the highest 
concentration at 67% compared with 60% in hominy feed, and followed by 
41% in bakery meal.

Slide 12
For the dietary treatments used in this experiment, we formulated eight 
diets. Seven diets based on each of the test ingredients: so we had a 
corn diet with 95.4% corn, a DDGS diet with 50% DDGS and 32.9% 
cornstarch, bakery meal diet with 97.4% bakery meal, corn gluten meal 
diet with 40% corn gluten meal and 38.3% of cornstarch, a corn gluten 
feed diet with 50% corn gluten feed and 28.3% cornstarch, corn germ meal 
diet with 60% corn germ meal and 18.4% cornstarch, and a hominy feed 
diet with 88.5% hominy feed. We also formulated a nitrogen-free diet 
which was used to determine the basal endogenous loss of amino acids and 
crude protein.

Slide 13
In this experiment, we used eight pigs with an initial body weight of 
82.5 kg, and they were allotted to an 8x8 Latin square design with eight 
diets and eight periods. Each period consisted of five day adaptation 
followed by two days of collection of ileal digesta. So these pigs, they 
were fitted with a T-cannula in the distal ileum, and digesta was 
collected from 8:00 in the morning until 4:00 in the afternoon on the 
two days of collection.

Slide 14
For the statistical analysis, we used the PROC MIXED procedure of SAS, 
and we had diet as a fixed effect, pig and period as random effects. 
However, we did not find significance for pig and period and therefore 
they were removed from the final model. For the mean values, we used the 
LSMeans procedure, and we used the Pdiff option if there was 
significance among the means with an alpha level of 0.05.

Slide 15
Now let's look into the results.

Slide 16
Now set up this graph. I'm going to show the standardized ileal 
digestibility only for the sake of this presentation, and we'll be 
looking at the digestibility of the first four limiting amino acids: 
lysine, methionine, threonine, and tryptophan. So on the Y-axis here, we 
have digestibility of lysine in percent, and on the X-axis we have our 
ingredients. So as we observed from this first graph, the SID of lysine 
was greater in corn gluten meal compared with DDGS, bakery meal, corn 
germ meal, and hominy feed, but that was not different from the SID of 
lysine in corn and corn gluten feed.

Slide 17
Now looking at the results for methionine, we observed that for corn 
gluten meal, the SID of methionine was also greater than the SID of 
methionine in DDGS, bakery meal, corn gluten feed, corn germ meal, and 
hominy feed, but not different from the SID of methionine in corn.

Slide 18
Looking at SID of threonine, once again, corn gluten meal had the 
greatest SID of threonine compared with all other ingredients except for 
corn and for corn gluten feed.

Slide 19
And looking now at the SID of tryptophan, corn gluten meal had the 
greatest SID of tryptophan compared with corn, DDGS, bakery meal, corn 
germ meal, and hominy feed, but the SID of tryptophan in corn gluten 
meal was not different from the SID of tryptophan in corn gluten feed.

Slide 20
Now we take a look at the SID for the mean indispensable amino acids, 
and we observed the SID of indispensable amino acids in corn gluten meal 
was greater than the SID of mean indispensable amino acids in DDGS, 
bakery meal, corn gluten feed, corn germ meal, and hominy feed, but not 
different from the SID of indispensable amino acids in corn.

Slide 21
So we conclude from this research that bakery meal is a poor source of 
digestible amino acids. Corn gluten meal, for most amino acids, had SID 
values that were greater than in DDGS and other co-products but similar 
to the values obtained for corn, and the digestibility of most amino 
acids in corn gluten feed and in corn germ meal were not different from 
the digestibility of amino acids in DDGS.

Slide 22
For hominy feed, the SID values for several amino acids were less than 
in corn, but because of the high starch concentration of this 
ingredient, it is possible that it may be used, not as a protein source, 
but as an energy source for pigs.

Slide 23
Some of the implications of our research is that we need further 
research to investigate the inclusion level in the diets of each of 
these ingredients that were tested here. For hominy feed, there is very 
limited data, so we need more research in evaluating this product, and 
for bakery meal, we hypothesized that the low lysine digestibility may 
be because of overheating when this product is produced.

Slide 24
Financial support for this research from Evonik Industries, the 
Maschoffs, and JBS United is appreciated. And the donation of corn germ 
meal, corn gluten meal, and corn gluten feed by ADM is also 
acknowledged.

Slide 25
With that, I would like to thank you for your time, and I hope you 
enjoyed this presentation. And I would encourage you to visit our 
website at nutrition.ansci.illinois.edu, where you will find useful 
information on a variety of other feed ingredients. Thank you.