Agrotechnologie

Abstrait

Effects of Organic Selenium and Zinc on the Aging Process of Laying Hens

V.G. Stanley, P. Shanklyn, M. Daley, C. Gray, V. Vaughan, A. Hinton Jr and M. Hume

The objective of the study was to determine whether supplementing the diets of post-molted hens with organic selenium (Se) (Sel-Plex®) and/or organic Zinc (Zn) (Bio-Plex®)1 could improve laying hen performance. Prior to molting, 120-78 wk old laying hens were separated into four treatment groups of 30 hens per treatment and were subjected to molting. Molting was induced by reducing photoperiod from 16 h per day to 8 h, and the diet was changed from a standard layer diet (17% CP; 2830 ME/kg) to a straight crushed corn diet. When egg production was reduced to zero, the hens were fed a control diet, or a diet supplemented with 0.3 ppm Se/kg of feed; 20 ppm Zn/kg of feed, or a combination of Se and Zn. Lighting was restored gradually to post-molting period. Changes in daily egg production, egg weight, egg quality (albumen, yolk, and shell weights), feed utilization and hen mortality were recorded. Results indicated that mean egg production was significantly (P<0.05) greater and feed utilization was significantly (P<0.05) lower for hens fed diet supplement with the combined treatment of Se and Zn compared to the other diets. Single treatment of Zn significantly (P<0.05) lowered mortality and increased egg production, but significantly (P<0.05) reduced egg, albumen and shell weights.