ABSTRACT We studied the influence of cereal, heat
processing of the cereal, and inclusion of additional fiber
in the diet on the productive performance and digestive
traits of broilers from 1 to 21 d of age. Twelve treatments
were arranged factorially, with 2 cereals (corn and rice),
2 heat-processing treatments of the cereals (raw and
cooked), and 3 sources of fiber (none, 3% oat hulls, and
3% soy hulls). Each treatment was replicated 6 (trial 1)
or 3 (trial 2) times. Growth traits were recorded in both
trials; digestive traits were measured in trial 1, and total
tract apparent retention (TTAR) of nutrients was determined
in trial 2. Feeding rice improved TTAR of all nutrients
and feed conversion from 1 to 21 d of age (P ≤ 0.001).
In addition, feeding rice increased the pH of gizzard digesta
(P ≤ 0.001) and reduced the relative weight (RW)
of most digestive organs. Heat processing had little effect
on the growth or size of digestive organs but improved