Reducing fat in duck lean is consider the first step towards improving
carcass quality. A total of 144 male and female, one day old white
Peking ducks were divided into 6 equal groups, each group subdivided
into 2 subgroup. One of them contain 12 males while the other contain
12 females.
Six dietary treatments were applied for both males and females have
the same group number. Basal diet supplemented with salbutamole 2mg
for 56 days (whole experiment period)(Treatment 1), or from 29-56
days of age)(Treatment 2), basal diet supplemented with Chromium
Piclonate 2mg)(Treatment 3), modified calorie protein ratio diet by
increasing protein concentration 0.5 % (0-2 weeks) and 2 % (3-8 weeks)
(Treatment 4), basal diet but after reduce the recommended level to 95%
of control diet for starter period and to 90% of control diet for grower
and finisher periods)(Treatment 5), while basal diet without supplementation,
modification, or restriction was as control (Treatment 6).
The results concerning growth performance demonstrated that salbutamol
or chromium supplementation and decreased calorie protein ratio
improved all parameters of growth performance. While restricted diet
reduced final body weight and final body weight gain but feed conversion
ratio was improved.
Carcass traits showed that dressing percentage and breast muscle was
increased. Skin and sub-cuteness Fat percentage was decreased. Meanwhile,
abdominal fat was reduced significantly with all dietary treatments
as compared with control. Also, chemical analysis of meat demonstrated
that muscular fat was decreased significantly in all treatments
compared with control, however, moisture content was increased.
Serum analysis showed that total cholesterol was decreased with all
dietary treatments while serum protein increased insignificantly in all
female groups but was significantly increased in all male groups as
compared with control.
It could be concluded that salbutamole and chromium supplementation
or decreased calori protein ratio improved all growth performance,
but restricted diet reduced final body weight while feed conversion
ratio improved. Dressing percentage and carcass characteristics were
improved with all dietary treatments. And cholesterol and cholesterol
L.D.L. reduced with all experimental treatments in both sexes compared
with control.