The artificial production of translucent streaks on egg shells and various factors influencing their development

Synopsis It is well known that translucent streaks can develop on egg shells due to damage to the surface of the shell. These “artifacts” have been produced under standard conditions and a study of them shows that the rate of development of the translucent areas up to their maximum brightness as measured by a scoring system can be expressed in simple mathematical terms. Having established this it was then possible to show that the rate of development of these translucent areas was (a) inversely related to the time of marking after the egg was laid, (b) directly proportional to external temperature and (c) affected by relative humidity so that a humidity between 10 and 30 per cent gave the maximum rate of development. Replacing the egg content with water or alcohol gave some interesting results. It was also found that the translucent streaks were weaker than corresponding opaque areas of the shell. The width of the streak produced under standard conditions varied greatly between the different eggs. The reasons for these various findings are discussed.