TITLE:
Age and Calcium Sources in Laying Hen Feed Affect Calcium Digestibility
AUTHORS:
Thiago Ferreira Diana, Arele Arlindo Calderano, Fernando de Castro Tavernari, Horácio Santiago Rostagno, Alexandre de Oliveira Teixeira, Luiz Fernando Teixeira Albino
KEYWORDS:
Dicalcium Phosphate, Digestion, Endogenous Calcium, Granulometry, Limestone
JOURNAL NAME:
Open Journal of Animal Sciences,
Vol.11 No.3,
July
20,
2021
ABSTRACT: The apparent calcium (Ca) digestibility coefficient (ADC) and true
digestibility coefficient (TDC) of different inorganic calcium sources were
determined in laying hens of different ages. Three Ca digestibility tests were
carried out, each assessing 240 Lohmann Brown lineage laying hens distributed
in a completely randomized design. Nine dietary treatments were arranged in a 3 × 3 factorial design consisting of three ages
(40, 50 and 70 weeks) × three Ca
(dicalcium phosphate (DCP) sources, fine (FL) and coarse (CL)) limestone,
comprising eight replicates per treatment of six birds per experimental unit.
Regarding the DCP, the ADC was higher (P as 0.889,
0.613 and 0.712, respectively. No effect (P > 0.05) of age on the ADC was
noted for either FL or CL. Comparing Ca sources, DCP exhibited a higher (P 0.05). Endogenous loss values of 790, 860 and 930 mg·kg-1 of consumed dry matter were observed at 40, 50 and 70 weeks, respectively. For
the TDC, no interaction (P > 0.05) was observed between Ca sources and bird
age. The highest TDC value (P > 0.05) was found in birds fed DCP (0.786)
followed by FL (0.637) and CL (0.534). In addition, birds at 40 weeks of age
(0.714) exhibited higher TDC values (P