An experiment was conducted to assess the
optimal levels of dietary lysine (Lys) in
Japanese quail from 7 to 21 days of age. A
dose-response diet was formulated to be adequate
in all amino acid concentrations with the
exception of Lys. Different levels of supplemental
L-Lysine.HCl were added to the doseresponse
diet at the expense of corn starch,
sodium bicarbonate, and NaCl to create 6 levels
of Lys ranged from 0.91% to 1.51% in diet.
Optimal Lys for feed conversion ratio, breast
meat yield, and thigh meat yield were estimated
at 1.15%, 1.21%, and 1.16% of diet, respectively,
based on linear broken-line regression.
With quadratic broken-line regression, the Lys
requirements for body weight gain, feed conversion
ratio, thigh meat yield, and breast
meat yield were estimated at 1.27%, 1.21%,
1.32%, and 1.34% of diet, respectively. Overall,
Lys requirements of starting Japanese quail
may be at least 1.34% of diet for optimizing carcass
attributes fed low-CP dose-response diet.