Control of landing flight by laying hens: implications for the design of extensive housing systems

Abstract

(1) Ten domestic hens (Lohmann Brown) were video-recorded while moving between perches at a horizontal distance of 0.6, 0.8 or 1.15 m apart. The take-off perch was either 0.2 m above or below the landing perch. (2) Weight and wing area of the hens were measured at the end of the experiment. The same measures where taken from 10 jungle fowls. (3) Clumsy or missed landings were observed on some downward flights over 0.8 and 1.15 m. (4) Hens' trajectories on take-off were closely related to the position of the target perch, and variation in take-off trajectory decreased as the distance between perches increased. (5) The standard deviation of the horizontal distance between head and perch, at the point when the feet first contacted the perch, did not vary with flight distance, suggesting that timing of foot extension was equally accurate at all distances. (6) The standard deviation of the vertical distance between head and perch, at the point when the feet first contacted the perch, did increase with distance, suggesting increasing difficulty in controlling the height of the flight trajectory above the landing perch. (7) Wing loading of the hens (mean 213 N/m2) was approximately twice that of the jungle fowl (mean 111 N/m2). (8) Loss of accuracy in hens' landings at greater distances can be attributed specifically to the effects of high wing loading on the ability to generate and control lift.

Causes of keel bone damage and their solutions in laying hens

“…High energy events within non-cage systems provide a likely mechanism for KF that have been suggested to result from collisions with elements of animal housing such as perches (Scott et al, 1997;Moinard et al, 2004a;Sandilands et al, 2009;Wilkins et al, 2011). Counter-intuitively, KF frequently occur in cage systems where there exists seemingly limited opportunities for dynamic loading as might occur during collision.…”

A review of environmental enrichment for laying hens during rearing in relation to their behavioral and physiological development

“…These effects appear particularly strong for hens in cages where they have restricted movement opportunities (Webster, 2004). Additionally, hens have higher wing loading (body mass relative to wing area) than their ancestors making them less agile during aerial locomotion (Moinard et al., 2004), which could, in turn, make them more susceptible to injuries. In particular, hens are prone to keel bone fractures, likely resulting from collisions within alternative housing systems (Campbell et al., 2016a; Gebhardt-Henrich et al., 2017).…”

Perch Positioning Affects both Laying Hen Locomotion and Forces Experienced at the Keel

“…Specifically, the increased latency to transition with steeper angles could suggest that hens required a greater amount of time to position themselves and cognitively process the information needed for flight including the position of the landing perch and/or thrust required for take-off. Moinard et al [ 26 ] calculated trajectories during take-off and landing by observing the eye position of hens in experimental flight and suggested that hens were gathering visual information about the perch to determine needed take-off thrust. Latencies in downward movements in our study were approximately 0.9 s greater than upward movements, which also agrees with existing literature that the former are more demanding [ 7 , 8 ].…”

“…The duration of balancing behaviors and latency to peck at the food reward in the current study was increased in longer and steeper transitions suggesting the greater difficulty of these movements. Moinard et al [ 26 ] suggested the greater variation in eye position relative to the perch during landing in more challenging transitions could relate to difficulty adjusting the hen’s position during flight. Our observations once the hen has landed could be an extension of those compensating behaviors performed in the approach period as the hen continues to adjust her position on the perch.…”