Hello, my name is Carly Rundle, and I am a PhD student working with Dr. Hans Stein. Today
I will be discussing research conducted at the University of Illinois investigating the
effects of isoquinoline alkaloid supplementation to corn-soybean meal diets on nutrient
digestibility and plasma characteristics of growing and finishing pigs.

I will start this presentation by giving a brief background as to what isoquinoline
alkaloids are and what they do, and then I will go over the materials and methods of this
experiment followed by results and conclusions from this research.

Subtherapeutic usage of antibiotics in livestock production has led to increasing consumer
concerns over antibiotic resistance, and as such, restrictions and regulations have been
put into place to limit the use of these AGPs. As a result, there is a need to investigate
alternatives to AGPs to promote health and maximize growth efficiency of production
animals.

Isoquinoline alkaloids, or IQ as I will refer to them in this presentation, are phytogenic
compounds that contain nitrogen. The alkaloids specific to this mixture include
sanguinarine, chelerythrine, allocryptopine, and protopine and are derived from the plume
poppy, shown in the image to the right of the slide.

When fed to animals, IQ have also been shown to improve growth performance of broilers,
layers, growing pigs, and beef cattle, including increases in average daily gain as well
as a reduction in average daily feed intake and subsequent improvement in the gain: feed
ratio.

IQ have been found to have antimicrobial, anti-inflammatory, and immunomodulatory
properties including inhibiting gram-positive and gram-negative bacterial cell division,
inhibition of NFKb resulting in a decrease in cytokine production, and a reduction in
neutrophil viability.

IQ have also been shown to reduce intestinal inflammation and improve barrier function
through a reduction in cytokine production and an increase in tight junction proteins ZO1
and claudin-1. Because of this, it is thought that these mechanisms of action of IQ may
lead to increased digestibility and absorption of nutrients.

It has been observed that IQ increases the digestibility of nutrients including amino
acids and crude protein, and previous research conducted at the University of Illinois has
revealed an increase in the apparent ileal digestibility of amino acids and starch by
young growing pigs fed corn-soybean meal diets.

Therefore, it was the hypothesis of this trial that IQ would increase the apparent ileal
digestibility (or AID) of amino acids, crude protein, starch, and acid hydrolyzed ether
extract and the apparent total tract digestibility (or ATTD) of crude protein and gross
energy when fed to finishing pigs.

We began the experiment with 4 corn-soybean meal diets, one control diet with no IQ, one
with 40 mg/kg IQ, one with 80 mg/kg and one with 160 mg/kg IQ. We then allotted these
diets to 12 pigs with an average initial body weight of around 77.2 kg. This experiment
was designed as a triplicated 3 x 4 incomplete Latin square with 3 replicate pigs per diet
per period and 3 experimental periods.

Each period consisted of 14 days, with a 10-day adaptation period to the treatments, fecal
collection on days 11 and 12, and ileal collection on days 13 and 14. On the last day of
each period, a blood sample was collected from each pig.

 And now I will move on to present the data from this experiment.

Setting up the graphs, we have the nutrient on the x axis, and AID on the y axis in
percent. Blue bars represent the control diets, orange bars represent the 40 mg/kg diet,
brown bars represent 80 mg/kg, and the grey bars represent 160 mg/kg. There was an
increase in the apparent ileal digestibility of crude protein with the greatest
digestibility observed in the 80 mg/kg treatment. However, digestibility of total amino
acids and starch was reduced at the 160 mg/kg treatment. Overall, there was no influence
of IQ on the AID of acid hydrolyzed ether extract.

Looking at specific digestibility of amino acids, there was an increase in the apparent
ileal digestibility of histidine, methionine, and proline, with the greatest digestibility
in the 40 mg/kg IQ diet.

A tendency for a reduction in the AID of isoleucine, leucine, lysine, and threonine was
observed in the 160 mg/kg IQ treatment, which is in agreement with the reduction in the
AID of total amino acids mentioned on the previous graph.

There was no influence of IQ on the apparent total tract digestibility of gross energy.
However, we did observe an increase in the ATTD of crude protein in the 80 mg/kg treatment
compared to the control treatment.

IQ did not affect the plasma urea nitrogen of pigs fed corn-soybean meal diets. However,
we did observe a decrease in albumin in the 40 mg/kg IQ treatment and a tendency for a
decrease in total protein at 40 and 80 mg/kg IQ, and an increase at 160 mg/kg.

There was a tendency for a reduction in the concentrations of arginine and tryptophan in
the plasma of pigs when IQ was supplemented, with the lowest concentration of amino acids
in the 160 mg/kg diet, which is in agreement with the finding that the AID of amino acids
was also lower in this treatment. However, there was no difference in the plasma
concentrations of histidine, lysine, methionine, phenylalanine or valine.

There was also a tendency for a decrease in the plasma concentrations of alanine and
proline at the highest IQ concentration, which is in agreement with the findings that the
AID of nutrients was reduced at 160 mg/kg, but there was no difference in the plasma
concentrations of serine and tyrosine or other dispensable amino acids when IQ was
supplemented.

We then replicated this experiment using growing pigs with an initial body weight of
around 25 kg. The treatments were kept the same, and the diets only differed in
concentrations of corn and SBM in order to accommodate the different amino acid
requirements of growing pigs compared to finishing pigs. We did not observe any
differences in the apparent ileal digestibility of crude protein or starch as IQ was added
to the diets for growing pigs. However, we did observe an increase in the AID of total
amino acids at 40 mg/kg IQ compared to the control diet and a decrease in the AID of acid
hydrolyzed ether extract as IQ was added at either 80 or 160 mg/kg.

Specifically looking at individual amino acids, there was an increase in the AID of
arginine, lysine, methionine, threonine, and valine, with the greatest digestibility in
the 40 mg/kg IQ diet, which is in agreement with the AID of total amino acids increasing
in the 40 mg/kg treatment.

Looking at the apparent total tract digestibility of nutrients, IQ did not influence the
digestibility of crude protein or gross energy in growing pigs, which is in contrast to
the finishing pigs, in which we observed an increase in the ATTD of crude protein as IQ
was included.

There was no influence of IQ on the plasma urea nitrogen, albumin, or total protein of
growing pigs. However, IQ did influence the plasma amino acids of the growing pigs. There
was an increase in the concentration of arginine, histidine and lysine and a tendency for
an increase in the concentrations of alanine and serine in the 80 mg/kg IQ treatment,
indicating that amino acid absorption was highest in the pigs fed that treatment.

From these experiments, we observed that the greatest digestibility values were in the 40
or 80 mg/kg IQ treatments. Therefore, we can infer that IQ increases the AID of crude
protein and amino acids and the ATTD of crude protein in growing and finishing pigs.

Combined with previous work conducted in our laboratory, we have concluded that
isoquinoline alkaloids increase digestibility of nutrients in the nursery, growing, and
finishing phases of production. Therefore, future research will focus on the effects of IQ
on the intestinal function, intestinal health, and immune parameters of growing pigs.

Thank you very much for listening to my presentation on isoquinoline alkaloid usage in
diets for growing pigs. if you have any questions about this work specifically, I can be
reached at rundle2@illinois.edu. And if you’d like to know more about the research
conducted in the Hans H. Stein Monogastric Nutrition Laboratory, please check out
nutrition.ansci.illinois.edu.