The aim of this study was to determine the effect of dietary protein levels
and supplementation of amino acids, kemzyme and urea on the performance of local
laying hens "Mandarah" fed low protein diet. Hens were fed isocaloric diets varying in
dietary crude protein being 14 or 16%, respectively. The lower protein diet was fed to
hens alone or supplemented with amino acids (methionine + lysine), kemzyme,
urea, amino acids + urea, kemzyme + urea or amino acids + kemzyme + urea, to
obtained 8 dietary treatments. During the experimental period, which lasted 30 weeks, 256 layers were
distributed equally into 8 dietary treatments (8 treatments x 8 replicates x 4 hens).
Results could be summarized as follows: -    Under the condition of the present study, layer hens fed diet containing 16%
crude protein significantly improved productive performance (body weight gain,
egg production, egg mass and feed conversion ratio) comparable with those
hens fed low protein diet (14% crude protein). -    Layer hens fed low protein diet supplemented with amino acids (methionine +
lysine) gave significantly better performance than that with other treatments and
control. While the addition of kemzyme, urea or the combination without or with
amino acids gave significantly lower performance compared with other
treatments. -    The egg components (yolk % and albumen % in relation to egg weight) and the
chemical composition of egg (protein and fat as percentages on dry matter) was
not affected by previous dietary treatments. -     Shell % in relation to egg weight significantly affected by dietary treatments while
shell weight, shell surface area and shell weight per unit of surface area were
not affected. -     The lowest feeding cost/egg value was demonstrated when layers fed the low
protein diet supplemented with amino acids and the value was 10% less than
that of layer fed the high protein diet.