FEEDING GENETICALLY ENHANCED SOY TO ANIMALS

Abstract

oybeans with transgenic events were approved for commercial use in the USA
in 1996. Currently, the majority of soy produced in the US, Canada and Argentina is
glyphosate resistant. Glyphosate or N-phosphono-methyl-glycine is the chemical
name for Roundup® Herbicide. This is the only transgenic soy that has been
approved for commercial use. To produce soybeans with tolerance to glyphosate, the
EPSPS gene from the Agrobacterium sp. strain CP4 was cloned into a bacterial
plasmid along with several other genes and DNA promoters to activate the genes.
Copies of this plasmid were then delivered to soybean cells to produce a transgenic
soybean or genetically enhanced soybean. Nutrients and antinutritional factors were
evaluated in glyphosate tolerant soybean seed together with soybean meal derived
from this seed. Proximate composition, urease activity, trypsin inhibitor and amino
acids content of soybean and soybean meal obtained from glyphosate tolerance line
is not significant difi'erent with the control soybean or soybean meal. There is also
no difierence in allergenicity between non-transgenic and glyphosate resistant soy.
In vitro digestibility result indicated that the protein is digested by digestive
enzymes. Fwding studies and laboratory analysis have been done to evaluate
whether any differences exist between non-transgenic soy and glyphosate resistant
soy. Studies in broilers, dairy cattle, rate and catfish have fotuid no difierences in
nutritional value between non-transgenic and glyphosate resistant soy. New types of
transgenic soy are currently being tested in the laboratory and hold promise for
additional beneficial traits such as higher phosphate and nitrogen digestibility and
higher levels of essential amino acids.