Egg quality characteristics, egg number, and body weight of spent layers fed with different levels of NaHCO3

One hundred and twenty spent (Babcock) egg-laying hens available at the age of 90 weeks were randomly divided into 12 experimental units of ten hens e ach. These experimental units were randomly allotted to four treatment grou ps viz., A, B, C, and D with three replications each. Groups A, B, and C we re fed on a layer mash diet supplemented with 2%, 4% and 6% Na HCO3, respec tively, while group D was kept on simple commercial layer ration which serv ed as the control. The maximum shell thickness (0.34 +/- 0.03 mm) was recor ded in birds which were served with 4% NaHCO3 in the feed and the minimum ( 0.29 +/- 0.03 mm) in the control group. The fewest eggs with weak shells we re recorded in birds served with 2% and 4% NaHCO3 in the feed (3.7 +/- 1.0 and 3.6 +/- 1.0, respectively) while the most occurred (7.4 +/- 0.6) in bir ds which were served with normal feed. The greatest number of eggs (4.7 +/- 1.0) were produced by the birds which were served with 2% NaHCO3 in the fe ed while the least (3.7 +/- 1.2) by the birds which were supplemented with 6% NaHCO3 in the feed and the control group (3,9 +/- 0.9). Haugh unit and y olk index values did not show any significant variation the levels of NaHCO 3 supplementation in the feed. The largess associated with body weight (1.5 8 +/- 0.11 kg) was gained by the birds supplemented with 4% NaHCO3 in the f eed.