Davood MohamadZamani - Department of Biosystems Engineering, Islamic Azad University,Takestan Branch, Takestan, Iran
Sirous Amini - Department of Biosystems Engineering, Islamic Azad University,Takestan Branch, Takestan, Iran
Seyed Mohamad Javidan - Department of Agricultural Machinery, Sari College of Agricultural, Mazandaran Province, Iran.
Saeed Dehghan - Young Researchers and Elite Club, Gorgan Branch, Islamic Azad University, Gorgan, Iran &Department of Biosystems Engineering, Tarbiat Modares University, Tehran, Iran

This research investigates the main specifications of eggshell which are the thickness of the shell and its strength. For this purpose random sampling was implemented on 180 fresh & healthy eggs of Bonz race produced at Ghazvin province agricultural jihad organization’s training center. To measure the shell thickness, four methods, including indicator hour measurement, ultrasound waves, micro-meter and photometer, were applied. Due to its precision, the indicator hour destructive measurement method was selected as the control method. By analyzing and comparing data collected through 4 treatments (methods) and 9 repeated treatments (Means) in the research, a significant difference between measurement methods was revealed. Moreover, comparing the measurement methods with the control method, the lowest measurement error was that of the ultrasound wave measurement method with 7.1% and the highest was that of the photometer method with 15.7%. Furthermore, regression equations are determined for the said measurement methods with the shell strength.

Egg, Shell, Thickness, Strength