Relation between social order and use of resources in small and large furnished cages for laying hens

Abstract

1. The objective was to determine the relation between social rank and use of resources in a small furnished cage with sufficient resources per hen (SF) and a commercial large one with less adequate allowance of facilities per hen (LF). 2. Ninety-two cross layers were used. At the age of 16 weeks, the hens were divided at random into two groups. There were 4 furnished cages with 5 birds per cage and 4 large furnished cages with 18 birds per cage. The dominance hierarchy was determined, in which highest, medium and lowest ranking hens in each cage were identified. Behaviour, use of facilities and physical conditions of these hens were measured (one in each rank category in SF, two in each in LF). 3. Dustbathing and litter scratching were more frequent in the high ranking hens than the medium and low ranked hens in LF, while no significant difference was found between them in SF. 4. No significant difference between SF and LF was found in use of nest boxes. However, pre-laying sitting tended to be less frequent in low ranking than medium and high ranking hens in LF (Social order x Cage design). In the nest box most of time was spent in pre-laying sitting by SF hens, LF high and medium ranked hens (average 94.9%). However, LF low ranking hens spent their time escaping (33.1%), pre-laying sitting (27.7%) standing (25.7%) and moving (13.5%) in the nest. 5. In the large furnished cages with less facilities per hen, high ranking hens may be expected to have priority using the dust bath. In contrast, low ranking hens rarely performed nesting behaviour fully, and spend more time using the nest box as a refuge than for laying.

Layer pullet preferences for light colors of light-emitting diodes

“…(2017) and Rierson (2011), who reported that poultry spent time in all given lighting environments during the preference test, no matter if it was a preferable lighting environment or not. Previous research have proved that dominant hens had priority use of resources, for example feeders, nest box and dust bath, resulting in subordinate hens not being able to use the facilities fully (Weeks and Nicol, 2006; Shimmura et al ., 2008). Specifically, in this experiment, birds with lower social hierarchy occasionally waited in a less desirable lighting environment until the birds with higher social hierarchy left the adjacent compartment, which may be part of the reason why poultry also spent time in less preferable environments.…”

A Sensitive Period of Peer-Social Learning

“…Amygdale modulates ventral striatum, thus the lesion of amygdale in juveniles affected social development [23] and personal (social) distance [24]. Domestic chicks' diversified socio-emotional behavior has been frequently reported such as pecking and flapping in group like 'play' [25] or isolated context with panic calls [26]. Cholinergic and other neurotransmitter systems control chick basal ganglia.…”

Overall welfare assessment of laying hens: Comparing science‐based, environment‐based and animal‐based assessments

“…In furnished cages, the quality of the resources, such as dust bath, may be more important than the cage floor area. Limited resources lead to competition, as well as behavioral restriction, which results in increased aggressive interactions and mortal-ity (Shimmura et al 2007a(Shimmura et al , 2008c(Shimmura et al , 2009). As mentioned above, these scores as a whole were supported by previous studies.…”

“…However, there are also a small number of scientific declarations that such separation is difficult. For example, the scientific declaration 'aggressive interactions were increased by decreased litter area' (Shimmura et al 2007a(Shimmura et al , 2008c(Shimmura et al , 2009) cannot be separated but should be attached to one measurement: 'litter floor'. Therefore, in this study, some measurements were not separated by behavioral/ motivational systems.…”