Abstract: The storage and preservation of egg has always been the focus of research in the egg industry. It has been demonstrated that egg quality has a close relationship with respiratory intensity. In order to further clarify the relationship between these two variables, chicken eggs from the same breed with different external qualities were selected and measured for respiration rate with a respiration rate mater. The correlation of respiration intensity with egg mass, egg shape index, egg specific gravity, shell mass, shell thickness, shell percentage and shell strength was analyzed using SPSS 19.0 software package. The results indicated that respiratory intensity was significantly positively correlated with egg mass (P < 0.05) and egg shape index (P < 0.05). A significantly negative correlation was observed between respiration intensity with both shell thickness and shell percentage (P < 0.05). However, the correlation of respiration intensity with shell strength, egg specific gravity and shell mass was not statistically significant (P > 0.05). In addition, there was a significantly positive correlation between egg specific gravity and shell strength, thickness and percentage (P < 0.01). A significantly positive correlation between shell strength and shell thickness was also observed (P < 0.01). In summary, it can be concluded that among the egg external quality parameters investigated, egg mass, egg shape index, shell thickness and shell percentage have the greatest effect on respiration intensity.

Key words: egg external quality, carbon dioxide, respiration intensity, egg shape index, shell thickness