7
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Effects of Dietary Calcium Levels on Productive Performance, Eggshell Quality and Overall Calcium Status in Aged Laying Hens

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          This study was conducted to investigate the effects of diets with varying levels of calcium on egg production, shell quality and overall calcium status in aged laying hens. A total of five hundred 70-wk-old Hy-Line Brown layers were divided five groups and fed one of the five experimental diets with 3.5%, 3.8%, 4.1%, 4.4%, or 4.7% Ca, for 10 weeks. There were no significant differences in feed intake, egg production and egg weight among groups. The cracked eggs were linearly reduced as dietary Ca levels increased to 4.7% (p<0.01). A significant linear improvement for eggshell strength and thickness were determined with increasing dietary Ca levels (p<0.01). The contents of serum Ca and phosphorus were not affected by dietary Ca levels. With increase in dietary Ca levels, the tibial breaking strength slightly increased. There were no significant differences in the tibial contents of ash, Ca and phosphorus among groups. In conclusion, eggshell quality, as measured by appearance, strength and thickness of eggshell, were influenced by dietary Ca content as expected (p<0.05). These results suggested that aged laying hens require relatively higher level of Ca than required levels from current Korean feeding standards for poultry.

          Related collections

          Most cited references 24

          • Record: found
          • Abstract: not found
          • Article: not found

          The Haugh unit for measuring egg quality

            Bookmark
            • Record: found
            • Abstract: not found
            • Article: not found

            Effect of Calcium Level of the Developing and Laying Ration on Hatchability of Eggs and on Viability and Growth Rate of Progeny of Young Pullets

              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found
              Is Open Access

              Duodenal calcium uptake, femur ash, and eggshell quality decline with age and increase following molt.

              An experiment was conducted to test the hypothesis that the decline in eggshell quality over time during egg production, and its improvement after molting, paralleled the rate of calcium uptake by the duodenum of the laying hen. In vitro duodenal calcium uptake rate and femur ash (percentage of femur weight) were determined at 37, 45, 51, 58, 68, and 72 wk of age. Percentage shell and shell thickness (millimeters) were determined at 22, 29, 36, 44, 50, 57, and 71 wk of age. Molt was induced at 63 wk of age. Three commercial strains DeKalb XL-Link, ISA/Babcock B-300V, and Hy-Line W-36 were compared. There were no differences in duodenal calcium uptake rate among strains. There was a significant decline (P < .01) in duodenal calcium uptake from 408 pmol/mg tissue per min at 37 wk of age to 329 pmol/mg per min at 58 wk of age. Femur ash decreased (P < .01) from 50.8% at 37 wk of age to 47.6% at 58 wk of age. Percentage shell and shell thickness declined (P < .01) from 9.79% and .403 mm at 22 wk of age to 8.88% and .373 mm at 57 wk of age, respectively. After the induced molt, duodenal calcium uptake increased (P < .01) to 402 pmol/mg tissue per min, and percentage shell and shell thickness increased (P < .01) to 10.23% and .389 mm, respectively. Duodenal calcium uptake increased immediately postmolt, whereas femur ash did not increase until 72 wk of age (P < .01).
                Bookmark

                Author and article information

                Journal
                Asian-Australas J Anim Sci
                Asian-australas. J. Anim. Sci
                Asian-Australasian Journal of Animal Sciences
                Asian-Australasian Association of Animal Production Societies (AAAP) and Korean Society of Animal Science and Technology (KSAST)
                1011-2367
                1976-5517
                October 2016
                18 January 2016
                : 29
                : 10
                : 1477-1482
                Affiliations
                Department of Animal Science and Technology, Konkuk University, Seoul 05029, Korea
                [1 ]Team of An Educational Program for Specialists in Global Animal Science, Brain Korea 21 Plus Project, Konkuk University, Seoul 05029, Korea
                [2 ]Animal Nutrition & Physiology Team, National Institute of Animal Science, RDA, Wanjugun 55365, Korea
                Author notes
                [* ]Corresponding Author: B. K. An. Tel: +82-2-450-3665, Fax: +82-2-452-9946, E-mail: abk7227@ 123456hanmail.net
                Article
                ajas-29-10-1477
                10.5713/ajas.15.0655
                5003974
                26954217
                Copyright © 2016 by Asian-Australasian Journal of Animal Sciences

                This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( http://creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

                Categories
                Article

                Comments

                Comment on this article