Early feeding in layer and broiler chickens

In commercial hatcheries, newly hatched chickens remain in the hatcheries until all chickens are hatched. Then they will experience various processes, such as selection and vaccination, until transported to a rearing farm. During this period, the chickens do not have access to feed and water until placement at the farm, which is called post-hatch feed and water deprivation (PHFWD). Research in broilers has shown that PHFWD, particularly when lasting 36 hours or more, can negatively affect performance and welfare. However, it’s unknown whether the 36 hours of PHFWD also holds for layers, since broilers are selected for meat production, while layers are selected for egg production. It is also poorly known whether or not other welfare-related aspects, which are more sensitive than mortality, are affected by PHFWD. It’s important to know whether PHFWD affects the welfare of layers in the short term or later life, because they have a much longer lifespan than broilers. This PhD project will use 3 pillars of welfare to measure the effects of PHFWD in layers, including 1) health and functioning, 2) natural behavior, and 3) affective state. To address this, this project contains 2 experiments. In experiment A, the first eating and drinking time post-hatch and feed and water consumption will be investigated, followed by the eating and drinking bouts for 12 hours after the start of eating and drinking. In experiment B, chickens will experience different durations of PHFWD and a plethora of measurements will be performed, related to the 3 indicated welfare pillars. As the effects of PHFWD on welfare may differ between white and brown layer strains (e.g. because strains differ in stress sensitivity), both strains will be studied. Additionally, the tests will persist to 12 weeks of age to determine whether the effects of PHFWD are short-term or long-term