The connection between the Colour of the Eyes, the Mortality, and the Production of White Leghorns. Het Verband tusschen de oogkleur van Witte Leghorns en de Herfte en de productie. Dr. J. B. van der Meulen. Landbouwkundig Tijdschrift, Vol. 50, 1938, p. 868.

An investigation, in which 406 White Leghorns of two different strains were used, on the connection between the colour of the eyes of normal healthy pullets at the beginning of the laying period on the one hand and the production and mortality during the pullet year on the other hand, led to the following conclusions:—

1. 1. The mortality amongst hens with abnormal colour of the eyes, (brown-grey and/or blue) is considerably higher than that amongst birds with normal orange coloured eyes, and the production of the former is on the average lower than that of the latter.

2. 2. Birds with one normal and one abnormal coloured eyes, correspond to birds with normal coloured eyes as far as mortality is concerned, but their average production resembles more than that of birds with two abnormal eyes.

3. 3. Not only an abnormal eye colour but also an abnormal shape of the pupil seems to point to higher mortality and the highest mortality is probable amongst birds which have both an abnormal colour, as well as an abnormal shape of the pupil.