The hen's egg: A rapid method for routine estimation of flock mean shell thickness

Abstract

1. A rapid, non‐destructive method of determining flock mean shell thickness, requiring only an automatic balance, a wire basket, a vessel containing water and a thermometer, is described.

2. An estimate of the mean effective shell thickness, T_e (mm), of a sample of eggs can be obtained in 3 min by the solution of the equation:

in which ΣW_e (g) and ΣV_e (mm)3 are the total weight and volume of the N eggs in the sample and m has the value 0.673456.

3. With a sample of 30 newly laid eggs the error standard deviation of T_e , considered as an estimate of the flock mean, is 3.8 μm.

4. If the eggs are stored before weighing, the weight loss due to evaporation must be estimated and allowed for.

5. It is not necessary to use a computer; the estimate of T_e can be obtained from a table (which is given), with simple interpolation and a correction for temperature.