Choline supplementation for Hisex White and Hisex Brown laying hens. 1. Performance and egg quality

Abstract

One hundred twenty eight Hisex hens (64 sixty three week-old Hisex White and 64 sixty four week-old Hisex Brown) were divided into eight groups containing 16 hens each. 4 experimental treatments were prepared by addition of choline to a corn-soy basal diet. The methionine level was 0.253 % for all the experimental diets, equivalent to 30% of the National Research Council requirements. The experiment was conducted for four 28-day periods (from April 10 to July 31). Egg production, feed conversion (kg/kg eggs) and percentage of shell did not differ significantly between strains feed conversion ( kg / dozen eggs) and Haugh units were significantly higher for Hisex White strain. The shell thickness and eqg specific gravity of the brown shell eggs were significantly greater than the white shell eggs. Hen performance and albumen height (Haugh units) did not differ significantly for any level of choline supplementation. Choline was effective in improving the egg shell quality (percentage of shell, thickness shell and egg specific gravity) .