caa a22 4500 397568320 CHVBK 20180308164834.0 cr unu---uuuuu 161202e199601 xx s 000 0 eng 10.3382/ps.0750062 doi (NATIONALLICENCE)oxford-10.3382/ps.0750062 Influence of Calcium and Environmental Temperature on Performance of First-Cycle (Phase 1) Commercial Leghorns [Elektronische Daten] [D. A. ROLAND, M. M. BRYANT, H. W. RABON, J. SELF, J. SELF] An experiment was conducted to determine whether optimizing profits, as well as eggshell and skeletal strength, by manipulation of dietary Ca level has any influence on either egg weight, egg production or feed consumption during the first 12 wk of production (Weeks 20 to 32, Phase 1). Hens were housed at two environmental temperatures (15.6 to 23.3 and 21.1 to 28.9 C) and fed six diets from 20 to 32 wk of age containing 2.5 to 5.0% Ca with increments of 0.5% and with ME levels ranging from 2,719 to 2,950 kcal/kg, respectively. Egg specific gravity, egg production, egg weight, and feed consumption were determined at weekly or biweekly intervals. At 32 wk of age, plasma Ca, bone density, and bone breaking strength were determined. Results indicated that environmental temperature had no influence on egg production but hens housed at the lower environmental temperature had an increase in egg weight, egg specific gravity, and feed consumption. Increasing dietary Ca level increased egg production, egg specific gravity, feed consumption, ionic plasma Ca, bone density, and bone breaking strength and had no adverse effect on egg weight. It was concluded that Hy-Line® W-36 hens could be fed diets containing as much as 5% Ca with no adverse effect on egg production, egg weight, or feed consumption and that Hy-Line® W-36 hens (Phase 1) under conditions described should be fed diets containing a minimum of 4.25% Ca (3.4 to 3.6 g per hen per d) to 4.5% Ca (3.6 to 3.8 g per hen per d). Calcium intake should range from 3.0 g per hen per d at 21 wk of age to 4.2 g per hen per d at 32 wk of age. © 1996 Poultry Science Association, Inc. Metabolism and Nutrition nationallicence calcium nationallicence commercial Leghorn nationallicence first-cycle hen nationallicence egg weight nationallicence ROLAND D. A. 2To whom correspondence should be addressed. aut BRYANT M. M. aut RABON H. W. aut SELF J. aut SELF J. Cal-Maine Foods, Inc., Jackson, Mississippi 39207 Poultry Science Oxford University Press 75/1(1996-01), 62-68 0032-5791 75:1<62 1996 75 ps https://doi.org/10.3382/ps.0750062 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.3382/ps.0750062 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- ROLAND D. A. 2To whom correspondence should be addressed aut NATIONALLICENCE 700 1- BRYANT M. M. aut NATIONALLICENCE 700 1- RABON H. W. aut NATIONALLICENCE 700 1- SELF J. aut NATIONALLICENCE 700 1- SELF J. Cal-Maine Foods, Inc., Jackson, Mississippi 39207 NATIONALLICENCE 773 0- Poultry Science Oxford University Press 75/1(1996-01), 62-68 0032-5791 75:1<62 1996 75 ps Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford