This study was designed to evaluate some physiological responses to
dietary betaine levels s in broiler chickens. One hundred and twenty, one-day-old
unsexed chicks, of Cobb strain, were used in experiment period of 6 weeks.. The birds
were allocated in four treatments,30 birds each (3 replicates of 10 birds). Treatments
were:T1 as control group (C); T2,Diet C plus 0.01% betaine; T3, Diet C plus 0.02%
betaine; T4, Diet C plus 0.03% betaine. Feed intake and body weight per replicate
were recorded weekly, Body weight gain (BWG) and feed conversion ratios (FCR)
were calculated. At the end of the experiments samples of chickens were randomly
chosen and slaughtered to determine dressing percentage and blood samples were
taken to measure serum Glucose, Cholesterol, Triglyceride, Total lipids, T3, T4 and
Albumin.The results showed that using of 0.03 % betaine of broilers diet had significant
differences on BWG, FI, and FCR compared with other groups at 3 and 6 wks of age.
The carcass weight was significantly (P<0.001) improved in 0.02 % Betaine. There
were a significant increase (P<0.01) in serum total protein, albumin, and globulin
concentrations of birds fed 0.03 % betaine levels compared to other treatments. The
results concluded that using of 0.03% dietary betaine showed beneficial of some
physiological and productive responses of broilers chickens.