The Effect of Phenoxy‐herbicides on the Hatchability of Eggs and the Viability of the Chicks

Abstract

The effect of the following phenoxy herbicides: 2,4‐D, 2,4,5‐T, MCPA, mechlorprop and dichlorprop on the hatchability of hens eggs and the viability of the chicks was investigated both by injecting the herbicides into the yolk and by immersing the eggs in a one or five per cent solution of the herbicides. The five herbicides were found to have rather similar embryotoxic qualities and the injection of about two mg herbicide per 60 g egg decreased the percentage hatch and in some cases the viability of the chicks. Immersion in a one per cent herbicide solution had no effect and immersion in a five per cent herbicide solution had only a moderate effect on the hatchability of the eggs and the viability of the chicks. The embryotoxic effect of 2,7‐dichloro‐dibenzo‐p‐dioxin was found to be at least 100 times that of the herbicides. In the injection experiments a considerable number of malformations was observed in the dead embryos at the high dose levels.