Development of pecking damage in layer pullets in relation to dietary protein source

1. In recent years, the UK egg industry has become increasingly dependent o n plant protein sources, in particular soyabean meal, and it has been sugge sted that this trend (and/or the concomitant absence of animal protein in l ayer diets) might be causally related to increased feather pecking and cann ibalism. 2. This study examined the development of pecking damage in relation to die tary protein source, by rearing 12 groups of 12 layer pullets to 24 weeks o f age on diets based on 'animal' (fishmeal) or 'plant' (soyabean meal) prot ein. 3. Damaging pecking began at 6 weeks of age, in three groups (one plant and two animal). Injurious pecking began at 18 weeks of age, and affected four groups (two plant and two animal). 4. Greater numbers of vigorous pecks/pulls were observed in plant protein g roups throughout the experiment; although they were significantly higher on ly between 13 to 16 weeks of age. Pecking damage scores did not differ betw een treatments. 5. Dietary protein source did not affect plasma oestradiol, progesterone or egg production. 6. These results do not support the notion that inclusion of fishmeal in la ying hen diets prevents or alleviates feather pecking and cannibalism.