High, low, or familiar? Nest site preferences of experienced laying hens
1. The aim of this study was to investigate which nest heights are preferred by high producing laying hens in the absence of familiar nest locations and whether preferred nest heights are more attractive than a familiar location. In two experiments, a total of 108 hens of four different layer breeds, which were at least 50 weeks of age, were studied. 2. In the first experiment, hens were given individual free choice between nests for one-week at four different heights (0 cm, 39 cm, 78 cm, 117 cm above ground) which were unequal to the familiar nest location. Hens of the four breeds differed in their nest height preferences (P=0.0013). Whereas hens of three breeds preferred ground level nests (P<0.007) and the fourth line showed an equal preference for the ground level and level three, the latter level corresponding to the height of the nests in their home compartments. 4. In the second experiment, hens from the four breeds were given a choice between ground level nests and nests at a familiar location, i.e. at the same location as in their home compartment. Hens of all strains preferred the familiar nest location (P=0.002) and preferences did not differ between strains (P=0.77). 5. Laying hens seem to prefer nests at ground level in the absence of a familiar nest. However, if possible, experienced 50 week old hens continue to use a familiar nest location instead of a ground nest location. The results are discussed with respect to a potential primary preference that may be modifiable by experience and with respect to possible relevance in commercial housing.