Group selection for adaptation to multiple-hen cages
This group of experiments were designed to evaluate the effect of selection of a line bred strain of White Leghorn hens for increased survivability and adaptability in multiple bird cages, and stressed environment. The selection policy was based on so called ''group selection'', where the sire family would be selected or rejected as a group rather that on an individual basis. Three groups of hens were involved in this experiment, those being (S) the selected line, (C) the random bred or control group and (X) the commercially available line of egg producing birds. The commercial line are known to be highly productive and routinely subjected to beak trimming while in commercial flocks. The birds were housed either individually (1H) or in multiple bird, so called colony cages in groups of 12 birds (12H). During these experiments the flocks were examined over a variety of factors . The hope of the study was that the selected S line of birds would show improved behaviour and decreased stress response and less dramatic production losses due to their selection for adaptability and survivability in colony cage environment.