Date:
SWINE RESEARCH SNAPSHOT
BACKGROUND INFORMATION
INDUSTRY IMPLICATIONS:
IMPORTANT FINDINGS:
ARTICLE EXCERPT:
PRIMARY CONTACT:
For further information please contact:
or visit: https://www.uoguelph.ca/osrn/
Summer 2018
Are non-essential amino acids "essential" for optimal health in swine?
High protein diets increase
environmental pollution
Diets formulated to meet
essential amino acid (AA)
content
Limited research on non
essential AA in low protein
diets
Glycine, a non essential AA
may limit growth
Glycine participates in DNA,
RNA, and collagen synthesis
Feeding low crude protein diets reduces nitrogen excretion
into the environment (i.e. in urine and feces) meaning that it
can reduce the impact of pork production. However, low
protein diets reduce non-essential AA content in the diet and
this can be a problem since non-essential AA can improve
processes other than growth performance in swine such as
the synthesis of collagen.
NON ESSENTIAL VS. ESSENTIAL AMINO ACIDS
Non essential AA are defined as AA that can be produced
within the body therefore they do not need to be added to a
diet. On the other hand, essential AA are required in the diet
since the body cannot make enough of them to support
growth and other body processes. In low protein diets,
Glycine endogenous synthesis may not be enough to keep
up with body processes and may limit growth in swine.
Glycine content in the diet did not change initial or final body
weight.
Diets with 100 and 60 % estimated requirement of Glycine
content (CON and LT) had improved skin collagen compared
to the other diets (Figure 1).
Who said non-essential amino acids are not important in
swine diets?.
ksilva03@uoguelph.ca
Date:
RESEARCH METHODS:
RESEARCH TEAM & ACKNOWLEDGEMENTS:
Summer 2018
Figure 1: Collagen abundance in swine fed diets with either 100%, 60%, or 20% estimated requirements
of Glycine content in the diet. CON= 100% Glycine, LG & LT = 60% Glycine, HG & HT = 20% Glycine.
Collagen abundance in the skin of pigs fed a low protein diet. Control diet (100% Gly content) and Low
Thr diet (60% Gly) had similar collagen content, meaning Thr rescued collagen content.
Forty-two barrows (initial body weight= 15 kg) were were fed one of five isonitrogenous diets. The Control
(CON) diet was formulated based on NRC (2012). The CON diet had 100 % Glycine content, the Low
Glutamate (LG) and Low Threonine (LT) had 60 % Glycine content, and the High Glutamate (HG) and
High Threonine (HT) had 20 % Glycine content. Glutamate and Threonine were added to make sure all
diets had equal protein content. Pigs were fed over a 21-day experimental period and weighed weekly to
determine average daily gain and feed intake. Skin samples were taken from each pig for collagen
analysis.
Kayla E Silva BSc1; Wilfredo D Mansilla, MSc, PhD1; Anna-Kate Shoveller, MSc, PhD1; John K Htoo,
PhD2; John P Cant, MSc, PhD1; Lee-Anne Huber, MSc, PhD1.
1 Department of Animal Biosciences, University of Guelph.
2 Evonik Nutrition & Care GmbH, Germany.
Financial support provided by: Evonik Nutrition & Care GmbH, Ontario Pork, Swine Innovation Porc,
OMAFRA.
Special thanks to de Lange lab, family and friends.