Laying hens prefer softer over harder mineral-based pecking stones and peck them more at the end of the light period.

Mineral-based pecking stones (PS) are edible enrichments for poultry that comprise a high proportion of calcium. We aimed to determine whether laying hens prefer a Soft (easier to ingest) versus a Hard mineral-based PS with the same calcium content, if pecking at PS follows a diurnal pattern similar to calcium appetite, and whether the PS affects eggshell quality. Shaver White laying hens housed in groups of 3 in furnished cages (N = 38) were given either a Hard or Soft PS for 15 days, followed by a 6-day washout period of no PS, and then the opposite PS type for an additional 15 days (Phase 1).

Rearing laying hens: Early environmental complexity and genetic strain have life-long effects on keel bone size and fractures.

Keel bone damage (KBD) is a major welfare concern for laying hens. Environmental complexity during rearing is suggested to promote skeletal development and reduce KB fractures (KBF). We investigated the effect of rearing environment and genetic strain on KB development and health.

Feeding flaxseed to chicken hens changes the size and fatty acid composition of their chicks' brains.

Diets fed to commercial chicken breeders are high in n-6 fatty acids (n-6 FAs) and low in n-3 fatty acids (n-3 FAs). N-3 FAs are essential for embryonic brain development. In precocial birds, like chickens, brain development and brain n-3 FA accrual occur primarily before hatching.

Raising laying hens: housing complexity and genetic strain affect startle reflex amplitude and behavioural response to fear-inducing stimuli.

Individual variation in fearfulness can be modified during ontogeny, and high levels of fear can affect animal welfare. We asked whether early-life environmental complexity and genetic strain affect fear behaviour in young laying hens (pullets). Four replicates of brown (B) and white (W) genetic strains (breeds) of layers were each raised in four environmental treatments (housing): conventional cages () and different rearing aviaries with increasing space and complexity ( < < ).

A wing-assisted incline running exercise regime during rearing increases initial flight velocity during descent in adult white- and brown-feathered laying hens.

Domestic laying hens rely primarily on their hindlimbs for terrestrial locomotion. Although they perform flapping flight, they appear to use maximal power during descent and thus may lack control for maneuvering and avoiding injuries on landing. This in turn may result in injury in open rearing systems.