To study the effect of different doses of dexamethasone on growh rate, feed cinversion ratio and body composition, a completely random designed experiment was conducted , using 60 male guinea pigs with initial weight of 350±50g and age of about two months.Four levels of dexamethasone: zero (group D0,as control), 1.5 (group D1.5), 3.0 (groupD3.0) and 4.5 (group D4.5)mg/kg body weight were treated. Mean daily gain was lower I group D4.5 (15.8±2.94 g/d ) compared to group D0 (17.71±2.59 g/d ), but the differences between groups were not significant. Mean feed consumption was lower (p<0.05) in group D1.5 (101.14±6.7 g/d ) as compared with D0(107.48±6.15 g/d ).Feed conversion in group D0(6.14±.08g/d ) was lower than that in group D4.5 (6.52±0.89 ) but there ware no significant differences between the groups.
Percentage of carcass crude protein was higher (p<0.05) in group d1.5(20.85±1.17 ) compared to group D4.5(19.6±1.05 ).the crude fat percentage was lower(p<0.05) in D4.5(10.75±1.79 )as compared to D0(14.67±0.6 ) and D3.0 groups (12.73±0.93 ) (p<0.05). The weight of visceral organs were not affected by different dose of dixamethasone but carcass weight was heavier (p<0.05) in groupD0(26.16±4.85g) as compared to that in group D3.0(20.75±2.9g).
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