A feeding trial consisting of 6 dietary formulations with 3 levels (25, 50 and 100 percent) of ground damaged palay (GDP) and damaged milled rice (DMR) was conducted on two commercial strains (Strains A and B) of broiler to determine and evaluate their potential feeding values as substitutes for corn in broiler diets. These dietary formulations were compared to a zero percent GDP-DMR substitution of corn diet and a standard commercial broiler mash in terms of the economically important traits of meat type chickens like feed consumption, gain in weight, feed conversion efficiency and carcass quality.

There was no significant influence of either strain or diet on the feed intake of the birds, although birds in the test diets consumed slightly lesser feeds than those in the control (pure commercial broiler mash) diet. Except for birds in the 25 and 50 percent GDP diets, all birds in other treatment groups consumed lesser feeds but they are not significantly different from birds in the zero percent GDP-DMR substitution of corn diet. Similarly, birds in Strain B have lower feed intake than birds in Strain A.

A significant change in body weight was noted among birds subjected to the experimental diets. But no significant difference was noted in the weight gain of the birds in the control diet when compared to those in the experimental diets.

Marked differences in feed conversion efficiency (FCE) were observed among birds subjected to the experimental diets but not when compared with those in the control. This was mainly due to the level of GDP and DMR substitution of corn in the diet.

Birds in Strain B fed with 50 and 100 percent DMR substitution of corn diet had significantly higher dressing percentage than birds in Strain A which were subjected to the same diet.

The level of GDP and DMR improved breast fleshing among the experimental birds and markedly reduced their skin and shank pigmentation.

Strain significantly influenced the feathering ability of all the birds including the control. Regardless of diet, Strain B had better feathering than Strain A.

Birds in the experimental diets had significantly lower cost of feed per unit gain in body weight than those in the control diet.

Mortality was not significantly affected by either diet or strain factors.

This study suggests that 50 and 100 percent damaged milled rice and 100 percent ground damaged palay substitution of corn can lower cost of feed per kilogram gain in weight and attain higher income-over-feed cost.

Thesis (Master of Science - Animal Science)

Includes appendices and bibliographical references