Abstract:
Objective of this study was to determine whether the adverse effects associated with high dietary rice
bran (RB) inclusion levels in broiler diets could be corrected by balancing diets for higher number of
amino acids (AA). The experiment followed a completely randomize design in 2x4 factorial arrange ment. Eight experimental diets were formulated using linear model based computer software
(CUFATotal Feed). Treatment factors were two dietary RB levels (20 and 40%) and four levels of AA
considerations in ration formulation (1. lysine and methionine, 2. 1 + isoleucine, 3. 2 + valine, 4. 3 +
threonine). When rations were balanced for lysine and methionine, many of the other AAs were in ex cess. No practical ration could be formulated to meet the threonine requirement. Twenty-two-day old
broiler chicks (n=144) were allocated into 48 pens and fed one of the eight experimental diets ad libitum
from 23-43 days. Balancing the diets for higher number of AAs had no significant effect on any of the
growth performance parameters. Live weight on day 43, weight gain from day 23-43 and feed intake
and the tibia ash contents of the broiler fed 40% dietary RB were significantly lower than those of 20%
RB fed counterparts. However, feed conversion ratios were not significantly different between the birds
fed two dietary RB levels. Interaction between RB levels and the number of AAs considered in ration
formulation was not significantly different with respect to any of the growth parameters measured. It
was concluded that balancing rations for up to four amino acids; lysine, methionine, isoleucine and va line did not mitigate the adverse effects of 40% dietary RB in broiler growth performance.
