Associations Among Beta Backscatter Measurements and Other Measures of Shell Strength

Abstract EGG shell strength presents a paradoxical situation since current measures of specific gravity and shell thickness are not highly correlated to actual shell strength as measured by impact or crushing methods (Tyler and Geake, 1963). Furthermore, there is insufficient proof that impact or crushing tests are highly related to the egg's ability to survive the marketing channels without becoming cracked or broken. The high relationship between specific gravity and actual shell thickness and the fact that specific gravity measurements are obtained on unbroken eggs has led to a widespread use of this technique in assessing shell quality. Tyler and Geake (1963, 1964a, b, c, d) described the associations between egg shell strength and crushing and impact test. They found that the waist was stronger than the broad pole, which, in turn, was stronger than the narrow pole by impact test. However, when crushing methods were used, the order was reversed, indicating . . .