caa a22 4500 397542593 CHVBK 20180308164730.0 cr unu---uuuuu 161202s1995 xx s 000 0 eng 10.1093/japr/4.3.276 doi (NATIONALLICENCE)oxford-10.1093/japr/4.3.276 Extra Dietary Calcium Supplement and Broiler Breeders [Elektronische Daten] [L. H. Reis, P. Feio, L. T. Gama, M. Chaveiro Soares] The influence of an extra dietary calcium supplement on egg specific gravity and hatchability performance was studied in a commercial broiler breeder flock at 43, 46, 56, and 64 week of age. A breeder flock of 28,000 was divided into two groups: a control group, which didn't receive the calcium supplement, and a treatment group, which received a coarse limestone supplement (g/hen/day) fed in the afternoon, from 43 wk of age onwards. Egg weight, specific gravity, egg weight loss during incubation, hatchability, and viability (hatchability of fertile eggs) were recorded, and researchers evaluated the influence of calcium supplementation and age of breeders on these traits. Egg specific gravity was significantly improved the coarse limestone supplement, but egg weight loss during incubation was unaffected. Hatchability and viability increased by about 3 percentage points when broilers received limestone in the afternoon, primarily as a result of a reduced incidence of contaminated eggs. As the flock aged, egg weight increased significantly (P < .05) and water loss during incubation showed little variation when expressed as a percentage of the egg weight when set (ca.11.5%). Fertility and viability declined with breeder age. © 1995 Applied Poultry Science, Inc. Broiler breeder nationallicence calcium supplement nationallicence egg specific gravity nationallicence embryonic mortality nationallicence hatchability nationallicence Reis L. H. Sociedade Agrícola da Quinta da Freiria, S. A., 2540 Bombarral, Portugal aut Feio P. Sociedade Agrícola da Quinta da Freiria, S. A., 2540 Bombarral, Portugal aut Gama L. T. Instituto de Estruturas Agrárias e Desenvolvimento Regional, Av. António Serpa, 26-1°, 1000 Lisboa aut Soares M. Chaveiro Instituto Superior de Agronomia, 1399 Lisboa Codex, Portugal; Phone: (01) 3638161; FAX: (01) 3635031 aut Journal of Applied Poultry Research Oxford University Press 4/3(1995), 276-282 1056-6171 4:3<276 1995 4 japr https://doi.org/10.1093/japr/4.3.276 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/japr/4.3.276 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Reis L. H. Sociedade Agrícola da Quinta da Freiria, S. A., 2540 Bombarral, Portugal aut NATIONALLICENCE 700 1- Feio P. Sociedade Agrícola da Quinta da Freiria, S. A., 2540 Bombarral, Portugal aut NATIONALLICENCE 700 1- Gama L. T. Instituto de Estruturas Agrárias e Desenvolvimento Regional, Av. António Serpa, 26-1°, 1000 Lisboa aut NATIONALLICENCE 700 1- Soares M. Chaveiro Instituto Superior de Agronomia, 1399 Lisboa Codex, Portugal; Phone: (01) 3638161; FAX: (01) 3635031 aut NATIONALLICENCE 773 0- Journal of Applied Poultry Research Oxford University Press 4/3(1995), 276-282 1056-6171 4:3<276 1995 4 japr Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford