Abstract: The study was conducted the effects of high zinc diets using zinc propionate on molt induction, postmoltlaying performance and egg quality in 66-wk-old hens.A total of 240 Lohmann( 2.46 kg) were randomly allocated to fourtreatments, 3 repeats every treatment, 20 hens every repeat. The birds were fed basal diets supplement with 0, 0.5%,1.0% and 1.5% zinc propionate, respectively. The results as follows: Feed intake, body weight, abdominal fat weight, ovaryweight and the number of yellow follicles were significant ly decreased( P< 0.05) in 0.5% , 100 % and 1.5% zincpropionate hens. Oviduct weight was also decreased( P< 0.05) in birds fed 1.0% and 1.5% zinc propionate diets.Serum LH, FSH and E2 concentrat ion were decreased( P< 0.05) in birds fed zinc propionate. Laying rate, relat ive eggshellweight , eggshell thickness were significantly increased( P< 0.05) after molting. It had no difference( P> 0.05) on eggweight, specific gravity, egg shape index, yolk index,Haugh score and albumen height. Conclusion: High zinc diets usingzinc propionate may induce to molt and improve the eggshell quality in hens.

Key words: Laying hens, Zinc propionate, Molt , Egg quality

CLC Number: 

• S831