Effect of early feed and water provision on layer pullet welfare

In commercial hatcheries, chickens experience several handling and processing procedures after removal from the incubator, such as pulling, sorting, sexing, vaccination, and transportation to the rearing farm. Chickens may not have access to feed and water until they reach the rearing farm, and this is referred to as the post-hatch feed and water deprivation (PHFWD) period. The PHFWD period may negatively affect chicken health and welfare. In broilers, PHFWD of 36 hours or more has been associated with higher mortality. However, it is unknown whether or not the 36 hours of PHFWD also holds for laying hen pullets and additionally, it is also poorly known whether or not other welfare related aspects, which are more sensitive than mortality, are affected by PHFWD. It is important to know whether PHFWD affects welfare in laying hens and to what extent as they have a much longer lifespan.

In this PhD project, we will use 3 pillars of welfare to measure the effects of PHFWD in layer chickens, including behavior and functioning, natural behavior, and affective state. Besides assessing the impact of PHFWD on laying hen welfare, it is valuable to determine when newly hatched chicks start eating and drinking and how much they eat and drink. To address this, this project contains 2 studies. In study 1, the start of eating and drinking immediately post hatching will be investigated, followed by the eating and drinking behavior during the first 72 hours after hatching. In study 2, chickens will experience different durations of PHFWD (0h, 12h, 24h, 36h, 48h, 60h, and 72h), 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 breeds, both white and brown layer pullets will be studied. Additionally, the test will persist to 12 weeks of age to determine whether the effects of PHFWD are short-term or long-term.