Effect of using different levels of iron with zinc and copper in layer's diet on egg iron enrichment.

摘要

Effect of Fe, Cu and Zn supplementation on egg Fe concn., performance and egg quality of 180 Mandarah laying hens (Egyptian local strain) at 24 wk of age, which were equally divided into 12 treatments, was investigated. The experimental treatments included 3 levels of supplemental Fe (0,100 and 200 mg/kg diet) in combination with Cu (0 and 20 mg/kg diet), Zn (45 mg/kg diet) and Cu (20 mg/kg diet) + Zn (45 mg/kg diet) in a 3 x 4 factorial arrangement during 3 interval periods (4 wk each). The highest concn. of egg Fe was observed for hens fed a diet supplemented with 200 mg Fe/kg in combination with Cu and Zn followed by those fed 100 mg Fe/kg with the same elements, resulting in egg Fe concn. of 3.85 and 3.59 mg/100 g egg, respectively. However, supplementation of Cu and Zn individually without Fe gave the lowest values of Fe in eggs. Fe supplementation either at the level of 100 or 200 mg/kg improved feed conversion and egg mass. The best value of feed conversion and egg mass was detected for those fed 100 mg Fe/kg with Zn supplementation. Egg quality was not affected by Fe supplementation. Zn supplementation resulted in the highest value of shell percentage, while Zn + Cu supplementation showed the best value of Haugh Units. Blood haemoglobin (g/100 ml) and PCV% increased significantly (P < 0.05) with increasing Fe level. Fe addition with Cu and/or Zn improved economical efficiency compared to the control.