The experiment was carried out on four groups of Hy-Line var. Brown hens (n = 350 each) fed on diets which provided 2.49, 3.07, 3.78 and, respectively, 4.15 g% calcium (Ca) during the laying period. Consequently, mean daily Ca intake was 2.74, 3.38, 4.16 and 4.60 g/cap., respectively. Ca metabolism was assayed at 20 weeks of age (start of the laying), 36 weeks of age (the peak of the laying) and 68 weeks (the end of the laying period). A significant part of the ingested Ca was not absorbed. The percentage of Ca exonerated by feces was higher at the start of the laying and lowers in the peak of laying and at the end of the laying period. The amount of Ca exonerated as unabsorbed Ca increases as the amount of ingested Ca increases inside of each age level. It was found also an increase of the Ca content of the egg shell according the Ca intake statistically significant (P<0.05) in 36- and 68-wk.-old hens, but not in 20-wk.-old hens. Blood plasma Ca showed significantly higher values in 3.38-, 4.16- and 4.60-g/day-Ca-intake groups when compared by 2.74-g/day-Ca-intake group (P < 0.05) but the level of increasing showed lowest values in hen groups with highest intake of Ca. The daily eggshell Ca export strongly correlates with the amount of daily Ca intake in 36-wk.-old hens and 68-wk.-old hens: r = +0.72 and +0.84, respectively, but no correlation was found in 20-wk.-old hens (r = -0.74, negative correlation). The results showed a limited physiologic capacity of the Ca absorption in hen, the Ca surplus being lost. Dietary Ca level should be closely correlated with the laying level of hens.
If the inline PDF is not rendering correctly, you can download the PDF file here.
An S.H. Kim D. W. An B. K. 2016. Effects of Dietary Calcium Levels on Productive Performance Eggshell Quality and Overall Ca Status in Aged Laying Hens. Asian-Austral. J. Anim. Sci. 29(10): 1477-1482.
Anderson K.E. Harvenstein G.B. Brake J. 1995. Effects of strain and rearing dietary regimens on brown-egg pullet growth and strain rearing dietary regimens density and feed space effects on subsequent laying performance. Poultry Science 1995; 74:1079-1092.
Barr A. 2008. Calcium homeostasis and vitamin D metabolism and expression in strongly calcifying laying birds. Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology. 151(4) 477-490.
Bölükbasi S.C. Çelebi S. Utlu N. 2005. The Effects of Calacium and Vitamin D in Diet on Plasma Calacium and Phosphorus Eggshell Calcium and Phosphorus Levels of Laying Hens in Late Laying Production Period. International Journal of Poultry Science. 4 (8): 600-603.
Dojană N. Preda C. Bălăceanu R. 2014. The Effect of Experimental Vitamin D administering on the Calcium Metabolism in Adult Laying Hens. Bulletin UASVM Veterinary Medicine 71(2) 349-352. DOI:10.15835/buasvmcn-vm: 10406.
Dojană N. Cotor G. Codreanu I. Bălăceanu R. 2015. The Effect of Experimental 17-beta Estradiol Administering on Calcium Metabolism Regulation in Young Laying Hens. Bulletin UASVM Veterinary Medicine 72(1) 90-92. DOI:10.15835/buasvmcn-vm: 10854.
Farner D.S. King J.R. Parker K.C. 1983. Reproduction in Birds - Avian Biology ed. Academic Press 3. 40-88. Hamilton R.M.G. and Cipera J.D. 1981. Effect of dietary calcium levels during the brooding rearing and early laying period on feed intake egg production and shell quality of White Leghorn hens. Poultry science. 60 349.
Pelicia K. Garcia E.A. Faitarone A.B.G. Silva A.P. Berto D.A. Molino A.B. Vercese F. 2009. Calcium and Available Phosphorus Levels for Laying Hens in Second Production Cycle. Brazilian Journal of Poultry Science. 11(1) 39 - 49.
Preda C. Bălăceanu R. Dojană N. 2013. Evolution of hormonal control of calcium and phosphorus metabolism in different hen breeds during the laying cycle. Bulletin UASVM Veterinary Medicine 70(2) 286-292.
Hurwitz S. 1990. Calcium homeostasis in avian species. Prog. Clin. Biol. Res. 342 586-591.
Hurwitz S. 1996. Homeostatic control of plasma calcium concentration. Crit. Rev. Biochem. Mol. Biol. 31 41-100.
Negoiţă I.S. Bălăceanu R.A. Dojană N. 2017. Calcium Intake Level as Factor of Influencing of the Eggshell Qualities in Laying Hens. Bulletin USAMV Cluj-Napoca. 74(2) 74-79.
Roland D.A. Sloan D. R. Harms R. H. 2002. Calcium Metabolism in the Laying Hen. 2. Patterns of Calcium Intake Serum Calcium and Fecal Calcium. Poult. Sci. 51(3) 782-787.
Roland D.A. Sloan D. R. Harms R. H. 2003. Calcium Metabolism in the Laying Hen. 3. Pattern of Feed (Calcium) Intake as Influenced by Time of Day and Oviposition. Florida Agr. Exp. Sta. Journal Series No. 4249 Florida U.S.A.