This project was conducted to characterise the underlying factors that contribute to layer hen individual feed efficiency and variation in flock feed efficiency throughout the production cycle, and to indicate new feeding layer hen management strategies to improve feed conversion ratio and egg quality, based on a greater understanding of high feed efficiency and low feed efficiency cohorts.

The key story emerging from these data is that inefficient hens are characterised by their putting on a lot more body weight from point of lay towards mid lay, and their eggs are of inferior quality. The reverse can be said for efficient hens, which retain a bodyweight close to or below the guidelines suggested for the breed target (in the case of this set of experiments, the ISA Brown). There is an association between productivity, body weight and liver health. Inefficient hens appear more prone to liver damage and fatty liver haemorrhagic syndrome. The depleted amino acids in the eggs of inefficient hens probably underpin the poor Haugh unit and are a target strategy for nutritionists to increase egg quality (and probably feed efficiency).