ILEAL PHOSPHORUS DIGESTIBILITY IN BROILER CHICKENS FED LOW CALCIUM AND PHOSPHORUS DIETS SUPPLEMENTED WITH PHYTASE AND CHOLECALCIFEROL
Keywords:
Cottonseed meal, phytase, vitamin D3, ileal phosphorus, broilersAbstract
A total of 125 1-day-old Arbor Acres broiler chickens fed broiler starter till day 20 were used to investigate the effect of low calcium and phosphorus diets supplemented with phytase and cholecalciferol. On day 21, the chicks were weighed and allotted to 5 treatments with 5 replicates of 5 birds each in a randomized complete block design. The treatments comprised a positive control (PC, T1) without cottonseed meal (CSM) and four CSM-based semi-purified diets, negative control (NC, T2), NC+vitamin D3-10,000 IU/Kg (T3), NC+phytase (T4) and NC+phytase+vitamin D3 (T5).
Titanium dioxide (TiO2) (5 g/Kg) was included as marker. Between days 25 and 27 post-hatch,
samples of fresh excreta were collected once daily from each cage. On day 28, the birds were
asphyxiated using carbon (IV) oxide and the birds dissected to obtain digesta from the distal two-third
of the ileum. All data were analysed using the GLM procedure in SAS. On day 28, the remaining birds
were killed and digesta from the 2/3rd of the ileum collected. Digestible P was significantly (P<0.05)
improved for birds on T5 when compared with the other four diets. Digestible P in T4 did not differ
(P>0.05) from the birds on T1. Ileal digestible phosphorus (IDP) significantly (P<0.05) reduced with
a corresponding increase in the percentage apparent phosphorus digestibility (APD) in T3, while T4
and T5 did not differ from T1 in the two parameters. It can be concluded that phytase and vitamin D3
supplementation on cottonseed meal improved digestible P in broiler chickens.