Response of broiler chickens to diets of varying protein contents under ad libitum and skip-a-day feeding regimes

Abstract

A 3×2 factorial experiment was used to investigate the effect of varying dietary crude protein levels;
optimum (control, 19.64% CP), low (17.72% CP) and high (21.66% CP) diets, fed ad libitum and on skip-aday bases on the performance and carcass characteristics of broiler chickens. The diets were isoenergetic. A total of 180 3-week old broiler chicks were used at three replicates per treatment and 10
birds per replicate. The feeding trial lasted for 5 weeks. Weight gain was lowest for chickens on low
protein diet compared with those fed the optimum (P>0.05) and high protein diets (P<0.05). Chickens fed
ad libitum gained more weight (1.62±0.13 kg/bird) than those fed on skip-a-day basis (0.95±0.07 kg/bird).
Chickens fed on skip-a-day basis had higher (P<0.05) feed conversion ratio (2.86±0.27) than those fed
ad libitum (2.59±0.27). Water intake of the birds significantly (P<0.05) increased with increasing dietary
protein. Abdominal fat deposition was promoted (P<0.01) by the low protein diet but reduced (P>0.05)
by skip-a-day feeding method. Other carcass characteristics were not influenced (P>0.05) by dietary
protein levels but a higher energy to protein ratio promoted the development of organs. Higher values
were recorded for carcass characteristics of birds on ad libitum feeding compared with skip-a-day
feeding. This study reiterates the benefit of feeding a balanced (optimum) protein diet, ad libitum to
broiler chicken finishers.