University of Guilan Animal Production Research 2252-0872 8 2 2019 08 23 Effect of organic and mineral zinc and butyric acid on performance and egg shell quality traits in different breeding periods Effect of organic and mineral zinc and butyric acid on performance and egg shell quality traits in different breeding periods 35 51 3516 10.22124/ar.2019.10874.1334 FA H. Yaghobi Taskooh MSc. Student of Animal and Poultry Nutrition, Gorgan University of Agricultural Science and Natural Resources, Gorgan, Iran M. Schams Shargh Associate Professor of Animal and Poultry Nutrition Group, Gorgan University of Agricultural Science and Natural Resources, Gorgan, Iran T. Ghoorchi Professor of Animal and Poultry Nutrition Group, Gorgan University of Agricultural Science and Natural Resources, Gorgan, Iran S. Hassani Professor of Genetics and Animal Breeding Group, Gorgan University of Agricultural Science and Natural Resources, Gorgan, Iran Journal Article 1970 01 01 The present study was carried out to investigate<br />the effects of different forms of zinc (no zinc, ZnO  and Zn-Met) and butyric acid on internal egg<br />quality traits and performance in Hy-Line W36 strain laying hens using 144<br />chickens from 74 to 83 weeks of age in the second phase of laying. A complete<br />randomized block design with 3 × 2 factorial arrangement with six treatments, six<br />replicates and four layers per replicate for nine weeks was used. Performance<br />parameters were measured daily and quality traits were measured in three<br />periods of age. The results of the experiment showed that the main effects of<br />organic acid and three forms of zinc on egg production, defective eggs, egg<br />weight, egg mass, feed conversion ratio and daily feed intake were not<br />significant during the whole experiment. During the period of 74 to 77 weeks,<br />feed conversion ratio for the treatment containing mineral zinc and organic<br />acid was higher than other treatments (<em>p < /em></em> The present study was carried out to investigate<br />the effects of different forms of zinc (no zinc, ZnO  and Zn-Met) and butyric acid on internal egg<br />quality traits and performance in Hy-Line W36 strain laying hens using 144<br />chickens from 74 to 83 weeks of age in the second phase of laying. A complete<br />randomized block design with 3 × 2 factorial arrangement with six treatments, six<br />replicates and four layers per replicate for nine weeks was used. Performance<br />parameters were measured daily and quality traits were measured in three<br />periods of age. The results of the experiment showed that the main effects of<br />organic acid and three forms of zinc on egg production, defective eggs, egg<br />weight, egg mass, feed conversion ratio and daily feed intake were not<br />significant during the whole experiment. During the period of 74 to 77 weeks,<br />feed conversion ratio for the treatment containing mineral zinc and organic<br />acid was higher than other treatments (<em>p < /em></em> https://ar.guilan.ac.ir/article_3516_0af3cba3d7d4bba84517aafecd7e6168.pdf