Frustration and production in purelines of chickens and their reciprocal crosses

Abstract

Frustration, fear and production traits were measured in four populations of White Plymouth Rock pullets that were maintained singly in wire cages. The populations consisted of two purelines and their reciprocal crosses. Significant differences were found between the purelines for frustration, as measured by head flicking. Means for the cross-line pullets were similar to that of the parental line with lower value, and significantly different from the parental line with the higher value. Highly significant differences were found among lines for fear, with the average of the reciprocal cross means being the same as the mid-parent average of the purelines. Within population, phenotypic correlations showed no relationship between frustration and fear. Also there was no evidence, under our husbandry conditions, that frustration and fear were associated with either body weight, age at first egg or egg production.