Recently, high tryptophan genetically modified (GM)-rice
has been newly developed and its tryptophan content was 50% higher than
conventional rice. The goal of this experiment was to clarify the
nutritive value of high tryptophan GM-rice on chicken growth performance.
Experimental treatments were the following, 1) NB (control) group; brown
rice (Nihonbare) based low protein diet in which all the deficient
essential amino acids except tryptophan were added to meet the nutritional
requirement, 2) NB+Trp group; control diet+crystalline tryptophan, 3) HW-1
(GM Trp) group; GM-brown rice (high tryptophan) based low protein diet in
which all the deficient essential amino acids except tryptophan were
added. Twenty one birds of Boris brown male chickens (7 days of age and
80±2 g of initial body weight) were used. They were assigned to three
experimental groups, each of which contained 7 birds. The birds were
individually housed in electrically heated battery cages maintained in
temperature constant (24 degrees) room. They had free access to
experimental diet and water during an experimental period of three weeks.
Body weight gain in NB+Trp group and HW-1 group were significantly higher
than that in control group. Similarly, higher feed intake in NB+Trp group
and HW-1 group compared with control group were observed. Feed efficiency
(gain/feed) in HW-1 group was significantly higher than in control group.
These results show that the nutritional value of high tryptophan GM-Rice
is similar to that of non-GM rice supplemented with crystalline