Effects of a premolt calcium and low-energy molt program on laying hen performance, egg quality, and economics

Thumbnail Image
Date
2012-02-01
Authors
Johnson, Anna
Stalder, Kenneth
Major Professor
Advisor
Committee Member
Journal Title
Journal ISSN
Volume Title
Publisher
Authors
Person
Johnson, Anna
Professor Animal Behavior and Welfare
Person
Stalder, Kenneth
Professor
Research Projects
Organizational Units
Organizational Unit
Journal Issue
Is Version Of
Versions
Series
Department
Animal Science
Abstract

The objectives of this study were to evaluate and compare the effects of production, physiology, egg quality, and economics of laying hens housed in a cage system when offered a calcium premolt treatment and low-energy molt diets versus a traditional feed withdrawal (FW) treatment during and after molt. In total, 981 Hy-Line W-36 laying hens (85 wk of age) housed 3 per cage were used. Six treatments were compared in a 2 × 3 factorial design with 2 calcium premolt treatments (fine and coarse) and 3 molt diets (FW, soybean hulls, and wheat middlings). The coarse Ca was a 50:50 mix of fine (0.14-mm mean diameter) and coarse (2.27-mm mean diameter) CaCO3, whereas the fine Ca was an all-fine CaCO3. Both diets were formulated to contain 4.6% Ca, such that only the particle size of the CaCO3 differed. Production parameters in experiment 1 included egg production, egg weight and mass, specific gravity, Haugh units, egg components, feed consumption and utilization, and BW. Physiological parameters in experiment 2 included ovary and oviduct weights, femur- and humerus-ash percentages, heterophil to lymphocyte ratios, plasma Ca and inorganic P concentrations, and alkaline phosphatase activity. Data were analyzed by ANOVA and P < 0.05 was significant. The fine-Ca premolt treatment was more effective than the coarse-Ca treatment at decreasing egg production during molt and increasing it postmolt, regardless of the molt diet. The FW molt diet resulted in the greatest decrease in production, but the soybean hulls diet resulted in lower production and ovary and oviduct weights during molt compared with those of the wheat middlings molt diet. Therefore, a fine-Ca premolt treatment and a low-energy molt diet, particularly soybean hulls, can be useful alternatives to a FW molt.

Comments

This is a pre-copyedited, author-produced PDF of an article accepted for publication in Poultry Science following peer review. The version of record v,91 (2012): 292, doi:10.3382/ps.2011-01685 is available online at: http://ps.oxfordjournals.org/content/91/2/292.full.pdf+html.

Description
Keywords
Citation
DOI
Copyright
Sun Jan 01 00:00:00 UTC 2012
Collections