Shell Associated Egg Quality Traits and their Value Estimation

Egg is a major source of human dietary protein with high biological value. It has been serving as a cheapest source of quality protein to meet the per capita animal protein requirement. The egg industry has shown a tremendous growth over decades. However market studies show that there is a huge demand for quality food than the cheaper food. Hence, overall egg quality that includes both external and internal quality traits are of utmost importance both for the producers and the consumers. The economic success of a laying flock solely depends on the total number of quality eggs produced. Poor egg shell quality which makes the egg inferior, is a huge hidden cost to the egg industries. Shell weight, shell thickness and shell ratio which affect the breaking strength or the number of cracked eggs to the market, are the most important traits to be considered apart from the traits like soundness, shape and colour of the shells. The earlier traits are not only important for the quality of infertile table eggs but they also affect the number of viable chicks from the fertilised eggs. Hence these quality traits are needed to be measured and compared to its optimal value on a regular basis. Therefore the authors have provided standard methods for measuring these shell associated quality traits and also have reviewed the estimated values for these parameters in different varieties of laying birds with latest reports.