Experience modulates emission of food calls in broody hens

The aim of these experiments was to determine if previous experience of chicks' response to food calling influences subsequent propension of maternal hens to utter food calls. Seventeen broody hens were tested three times a day without their 3- or 4-day-old chicks. Hens were tested in two situations: chicks were returned either after each test or at the end of all the day's tests. As palatability influences food calling in maternal hens, experiments were conducted first with a highly preferred food item and then with the hens' usual feed. The chicks' capacity to respond regularly to their mother influences the hens' capacity to emit food calls. In fact, although the hens did not lose their maternal state, they uttered fewer food calls when their chicks were removed all day. These results suggest that the chicks' behaviour following food calling could be a social reinforcement for broody hens.