An important indicator of the health and behavior of laying hens is their plumage condition. Various scoring systems are used, and various risk factors for feather damage have been described. Often, a summarized score of different body parts is used to describe the overall condition of the plumage of a bird. However, it has not yet been assessed whether such a whole body plumage score is a suitable outcome variable when analyzing the risk factors for plumage deterioration. Data collected within a German project on farms keeping laying hens in aviaries were analyzed to investigate whether and the extent to which information is lost when summarizing the scores of the separate body parts. Two models were fitted using multiblock redundancy analysis, in which the first model included the whole body score as one outcome variable, while the second model included the scores of the individual body parts as multiple outcome variables. Although basically similar influences could be discovered with both models, the investigation of the individual body parts allowed for consideration of the influences on each body part separately and for the identification of additional influences. Furthermore, ambivalent influences (a factor differently associated with 2 different outcomes) could be detected with this approach, and possible dilutive effects were avoided. We conclude that influences might be underestimated or even missed when modeling their explanatory power for an overall score only. Therefore, multivariate methods that allow for the consideration of individual body parts are an interesting option when investigating influences on plumage condition.

Within the European Union, dustbathing material in cage-housing systems for laying hens became compulsory in 2012. In practice, most producers use food particles as litter substrate. The feed is dropped in small amounts on scratching mats by an automatic transporting system. However, because dustbathing behavior is meant to remove stale lipids from hens' plumage, food particles may not be a suitable substrate due to their fat content. This study analyzes feather lipid concentration (FLC) of laying hens with access to food particles (F) or lignocellulose (L) as litter substrates. In each of 2 identical trials, 84 laying hens of 2 genotypes (Lohmann Selected Leghorn, Lohmann Brown) were kept in 12 compartments (7 hens each). Compartments were equipped with a grid floor and additionally contained a closed dustbathing tray holding F or L. Feather samples (150 feathers) were taken 2 times throughout the experiment. At 23 wk of age, 4 hens per compartment were sampled after they were allowed pair-wise access to a dustbath for 2.5 h and 3 hens were sampled without access to a dustbathing tray (control). After 10 wk of free access to the dustbathing trays, all hens were sampled again. In trial 2, an additional third sampling was made after dustbaths had been closed again for 6 wk. Here, 6 hens per compartment were sampled immediately before and after a dustbath. Dustbathing in F resulted in higher FLC compared with L and control (P < 0.001), whereas no significant difference was found between L and control (P = 0.103). When open access to litter was provided, hens had higher FLC in F compared with L (P < 0.001). The FLC immediately after dustbathing in F was higher compared with the level before dustbathing (P < 0.001), whereas it was lower after dustbathing in L (P = 0.006). These results show that F are not suitable litter material for laying hens because they lead to lipid accumulation on the plumage.

1. The prevalence of keel bone deformities in laying hens is high and is partly associated with unsuitable perch designs, which impose a risk of injury due to an unstable footing. 2. Over two experiments, 9 or 10 hens of each of three layer lines (Lohmann Selected Leghorn (LSL), Lohmann Tradition (LT) and Lohmann Brown (LB)) were filmed while landing on three different perch types, including steel perches of various diameters, a commercial mushroom-shaped plastic perch and a newly developed prototype perch with a soft surface material. 3. Data on landing behaviour (safe vs. unsafe or failed landing) following downward jumps were collected for 25, 50 and 60 cm vertical distances and 75 cm horizontal distance between a wooden start perch and the different destination perches. 4. The highest proportion of safe landings occurred on the prototype perch, whereas least safe landings were observed on steel perches, irrespective of their diameter. The mushroom-shaped perch was intermediate with regard to the safeness of landing. 5. A threshold of 50 cm vertical distance (34° slope) was identified as the optimum for downward jumps on perches in order to reduce the risk of unsafe or failed landings. Above this threshold, the proportion of safe landings declined significantly. 6. Brown shell layer types (LB and LT) had a lower proportion of safe landings compared to the white shell layer type (LSL), whereas no difference was found between LB and LT layer lines. 7. Although steel perches prevail in commercial housing, these perches were found to be least advantageous with regard to landing behaviour. The prototype perch provided the most stable footing on perching and is a promising alternative to replace commercial steel perches, thus helping to reduce the risk of perch-related keel bone injury.

Laying hens usually select an elevated position for resting at night-time. A previous study showed that the position a hen takes during resting was affected by perch material, most probably due to its thermal conductivity. The aim of the present study was to analyse the effect of perch surface temperature on resting behaviour and resting comfort in laying hens. In each of two identical trials, three groups of five Lohmann Selected Leghorn hens were housed in each of three compartments in turn (n = 30 birds in six groups). Compartments were equally equipped with one smooth, round galvanised steel perch of 34 mm external diameter. The surface temperatures of perches were controlled by passing water through them, giving temperatures of 15 °C, 18 °C (room temperature) and 28 °C respectively in the three compartments. Hen behaviour was observed at night-time by investigating the proportion of active behavioural patterns and resting (standing or sitting), either with 'head forward motionless and neck withdrawn' or 'head tucked backwards into feathers above wing base or behind a wing.' The number of hens perching and the time spent perching were unaffected by perch temperature. Hens' resting postures, however, were strongly influenced. On the warmest perch, hens rested more with their head forward in a standing position and showed more active behavioural patterns compared to both cooler perches (P < 0.001). On the cooler perches, hens rested more with their head covered by feathers in a sitting and standing position (P < 0.05). Our data show that perch temperature strongly affects laying hens' resting behaviour. In this context, hens are confronted with arising trade-offs between thermoregulatory adjustment of behaviour, optimisation of energy budget, restful roosting and vigilance behaviour.

The provision of perches in housing systems for laying hens is meant to improve hens' welfare by allowing a more natural behavior repertoire. However, the use of perches is associated with welfare problems, such as keel bone deviations and foot pad lesions, that may possibly result from high mechanical pressure load during extended perching activities. The aim of this study was to analyze peak force and contact area of hens' keel bones and foot pads on solid test perches of square, round, and oval shape with 3 different diameters each (experiment 1) and on commercially used perches (round steel tube, 2 sizes of mushroom-shaped plastic, and flattened round plastic) together with 2 prototypes of soft, round polyurethane perches (experiment 2). Test perches were covered with a pressure sensor film and 36 laying hens (18 Lohmann Selected Leghorn, 18 Lohmann Brown) were consecutively placed on each perch in an experimental cage during nighttime. Peak force (N/cm(2)) and contact area (cm(2)) were measured while hens were sitting and standing on the different test perches. Pressure peaks on the keel bone were approximately 5 times higher compared with single foot pad. On square perches, keel bone peak force was lower (P < 0.05) and contact area was larger (P < 0.001) compared with round and oval perches. In addition, peak force on foot pads in standing hens was higher on square perches (P < 0.05) compared with oval perches. Perch size did not affect peak forces on keel bones in sitting hens and foot pads in standing hens (experiment 1). On prototype perches, peak force on the keel bone was lower and contact area was larger compared with all commercial perches tested (P < 0.001). Peak force on foot pads was lower on prototype perches compared with steel perches (P < 0.01; experiment 2). Perches with a soft surface may possibly reduce keel bone and foot pad welfare problems in perching laying hens.

Within the European Union, the provision of dustbathing material in layer housing systems will be compulsory beginning in 2012. In cage systems, food particles are mainly used as litter material and are provided on scratching mats by an automatic transporting system. However, because dustbathing is a means for hens to remove stale lipids from their plumage, lipid content of a substrate may be an important asset with regard to its adequacy. This study analyzes dustbathing behavior as affected by lipid content of feed used as litter material. A total of 72 laying hens of 2 genotypes (Lohmann Selected Leghorn, Lohmann Brown) were kept in 12 compartments (6 hens each). Compartments were equipped with a plastic grid floor (G) and additionally contained 3 different dustbathing trays (each 1,000 cm(2)/hen) holding low-lipid (0.82%; L), normal-lipid (4.2%; N), and high-lipid (15.7%; H) food particles. The experiment began at 20 wk of life, and video recordings were done at wk 23, 26, and 29. Number of dustbaths, time spent dustbathing, average dustbath duration, foraging, and single behaviors within dustbaths were analyzed during the light period over 2 d in each observation week. Dustbaths occurred most frequently in the L compared with the N, H, and G treatments (all P < 0.001). Total time spent dustbathing was longest in the L treatment compared with the N and H treatments (P < 0.001). No difference in the average duration of single dustbaths was found between the L, N, and H treatments. However, when dustbath interruptions (less than 10 min) were excluded, the duration of single dustbaths was longer in the H compared with the L (P = 0.009) and N (P = 0.024) treatments. Foraging was most frequently observed in the N compared with the L, H, and G treatments (all P < 0.001). More body wing shakes occurred in the L compared with the N treatment, and the number of vertical wing shakes was higher in the N compared with the H treatment (all P ≤ 0.05). Our results showed that preference for a dustbathing substrate increased with decreasing lipid content, implying that food particles may not be a suitable dustbathing substrate.

1. The objectives of the present study were to validate a reduced, non-intrusive version (RLS) of the LayWel plumage scoring system in domestic laying hens with reference to complete, intrusive scoring (CLS) and to investigate the effect of these two scoring methods on corticosterone metabolite concentrations. 2. A total of 312 medium-heavy laying hens from 4 commercial hybrids kept in 24 floor pens were scored by two experienced teams. Another 150 hens from two hybrids kept in 6 pens were used for estimating scoring treatment effects on corticosterone metabolites in droppings. 3. Plumage scores were in general higher using the RLS method compared to the CLS method. The agreement between teams for plumage scores (CLS) were on a high (total score) to an excellent (single body part except breast and cloaca) level. 4. Birds subjected to CLS tended to have higher concentrations of corticosterone metabolites in droppings 2 h after scoring compared with birds in the control treatment (not scored). Birds subjected to RLS had intermediate concentrations. 5. It was concluded that a reduced version of the LayWel scoring system is a valid and reliable scoring method which tends to induce less stress to the subjects than the original procedure.

Seit 2009 sind Sitzstangen in allen Haltungssystemen fur Legehennen in Deutschland gesetzlich vorgeschrieben. Obwohl Sitzstangen das Verhaltensrepertoire der Hennen erweitern, ist ihr Einsatz mit einer erhohten Pravalenz an Brustbeindeformationen und -frakturen assoziiert. Ursachlich werden ungewollte Kollisionen mit Sitzstangen, rutschige Stangenoberflachen sowie ungunstige Sitzstangenpositionierungen diskutiert. In diesem Zusammenhang erscheint eine sichere Fusungsstabilitat auf einer Sitzstange ein wesentlicher Faktor zu sein, die Brustbeingesundheit positiv zu beeinflussen. Das Ziel dieser Studie war es, das Landeverhalten von Hennen dreier Legelinien (LSL, LB, LT) auf drei verschiedenen Sitzstangentypen zu analysieren, um Hinweise fur eine optimale Sitzstange im Hinblick auf eine hohe Fusungssicherheit beim Landeanflug zu erhalten. Zehn Hennen pro Legelinie wurden trainiert, von einer erhoht angebrachten Abflugstange auf eine niedriger installierte Testsitzstange fur eine Futterbelohnung zu springen. In zwei identischen Durchgangen wurden den Hennen eine runde Stahlstange (42 mm Durchmesser), eine pilzformige Kunststoffstange (43 mm) sowie eine runde Prototypstange mit Polyurethanoberflache und Luftpolster (48 mm) als Teststangen angeboten. Die vertikalen Distanzen zur Abflugstange betrugen 25, 50 und 60 cm bei gleichbleibender horizontaler Distanz von 75 cm. Pro Durchgang ergaben sich neun Sprungkombinationen pro Henne. Das Landeverhalten der Hennen wurde mit einer Videokamera aufgezeichnet und anhand einer dreistufigen Skala (1: sichere Landung, 2: unsichere Landung mit Balance- und Korrekturbewegungen, 3: Fehllandung ohne Halt auf der Stange) analysiert. Fur die Datenauswertung wurden jeweils zwei binomial verteilte Variablen kreiert (sichere Landung (1) vs. nicht sichere Landung (2 +3) und Fehllandung ohne Halt (3) vs. Landung mit Halt auf Stange (1 + 2)). Die statistische Auswertung erfolgte mittels GENMOD (SAS, Version 9.1). Weisleger zeigten mehr sichere Landungen (p = 0,003) und weniger Fehllandungen (p = 0,006) im Vergleich zu Braunlegern. Der Stangentyp ubte einen signifikanten Einfluss auf den Anteil sicherer Landungen (p < 0,001) und das Vorkommen von Fehllandungen (p = 0,011) aus. Auf der Prototypstange wurden mehr sichere Landungen im Vergleich zur Stahl- (p < 0,001) und pilzformigen Stange (p = 0,019) beobachtet. Weiterhin traten weniger Fehllandungen (p = 0,003) im Vergleich zur Stahlstange auf. Der Anteil an Fehllandungen (p = 0,018) stieg und der Anteil sicherer Landungen (p = 0,027) sank mit steigender vertikaler Distanz. Der Einsatz der Prototypstange konnte aufgrund der hohen Landesicherheit ein vielversprechender Ansatz sein, Brustbeinprobleme bei Legehennen zu reduzieren.

Behavioural observations were conducted at two different farms in Lohmann Selected Leghorn (LSL), Lohmann Brown (LB) and Lohmann Silver (LS) laying hens kept in furnished cages (Aviplus (AP)), small group systems (Eurovent 625a-EU (SG)) and modified compartments of small group systems (MSG) with three variants of elevated perches (back perches elevated (BE), front perches elevated (FE), both perches elevated (ST)). The study comprised three trial periods and layers' use of functional areas (wire floor, dust bath, nest box, perch), resting behaviour, locomotion and dustbathing and pecking behaviour were analysed during daytime. The highest number of hens on the wire floor was recorded in AP. Hens in SG and MSG showed highest locomotion activities. The frequency of hens walking on the wire floor was highest in ST compartments when longer distances could be covered without crossing non-elevated perches. Dust baths were frequented more often for other activities rather than dust bathing behaviour. Feather pecking and pecking against objects was highest in AP (LSL, LB), whereas in LS layers, it mainly occurred in MSG. Perch use was highest in SG with non-elevated perches. In all three variants of MSG compartments, elevated back and/or front perches were only used to a small extent and highest perching and resting activity was observed on non-elevated perches. The study shows that SG and MSG housing systems could increase layers' locomotion activities, whereas the possibility to perform dust bathing appears insufficient. However, in LS hens, dust bathing on wire floor was more frequent in AP compared to SG and MSG and in the latter two systems more dust-baths were performed on dustbathing mats in comparison to wire floor. Elevated perches were only accepted to a small extent during the day, which might be due to inappropriate perch design and/or perch position.

Resting on perches is an important behaviour for laying hens. However, perches in laying hen husbandry systems are associated with health problems which may result from inadequate perch designs. The aim of this study was to focus on particular behavioural patterns shown by laying hens on different perches during night-time in order to test whether perching behaviour may provide information on the suitability of a particular perch design. A total of 60 Lohmann Selected Leghorn hens were kept in six compartments over two identical trials. Hens were randomly offered nine round perches, which differed in material (wood, steel, rubber cover) and diameter (27, 34, 45mm) for one week each. Duration of resting, standing, preening and frequencies of balance movements and comfort behaviours shown by individual hens on each perch were recorded throughout one night (10.5h) on day six of each observation week. Balance movements decreased with increasing perch diameter (P<0.001) and appeared less on rubber perches compared to wood and steel (P<0.05). On steel perches, hens rested longer with their heads tucked backwards into their feathers (P<0.001) and less with their heads forward with neck pulled back compared to wood and rubber perches (P<0.001) irrespective of perch diameter. Standing was shown less often on steel compared to wood or rubber perches (P<0.001). Our data provide evidence that a detailed analysis of hens’ perching behaviour can give important information on the suitability of a perch design related to diameter and material. In this context, balance movements may be the most sensitive indicator of the suitability of a perch design with respect to stable footing on perch, whereas resting position and standing on perches are likely to be related to thermoregulatory adjustment in behaviour.

The provision for dustbathing material will be a legal requirement in cage-housing systems for laying hens within the European Union beginning in 2012. At present, food particles are widely used and typically offered in small amounts on Astroturf mats one or more times per day to facilitate dustbathing, pecking, and scratching. In the present study, we compared layers' preference for food and 3 other (nonnutritive) substrates for foraging and dustbathing. In each of 2 identical trials, 72 hens of 2 genotypes (Lohmann Selected Leghorn and Lohmann Brown) were kept in 12 compartments (6 hens each). Compartments were equipped with a plastic grid floor and additionally contained 4 different dustbathing trays (each 1,000 cm(2)/hen) holding either wood shavings (WS), lignocellulose (LN, soft wood fiber, pelleted), Astroturf mat without substrate (AT), or food particles (FP). Hens were housed from 18 wk of age and video recordings were done at wk 21, 24, and 27. Time spent and frequency of dustbathing, duration of a single dustbath (DB), frequency of foraging behavior, and relative frequency and duration of behavioral patterns within a single DB were recorded during the light period over 2 d in each observation week. The FP treatment was preferred for foraging over WS, LN, and AT. Time spent dustbathing and number of DB were higher in LN compared with WS, FP, and AT, whereas average duration of a single DB was longer in FP compared with LN and WS. More vertical wing shakes and scratching bouts within a single DB were observed in LN compared with AT. Bill raking occurred more frequently in WS and LN in comparison to FP and AT. No differences in the relative durations of behavioral patterns within a single DB were found. In conclusion, FP were preferred for foraging but not for dustbathing, indicating that FP may not be an optimal dustbathing substrate for laying hens.

Welches Einstreumaterial Legehennen in der Kleingruppenhaltung zum Staubbaden bevorzugen, sollte ein Wahlversuch zeigen. Untersucht wurde auch, welche Eigenschaften eines Substrats fur die Wahl der Hennen ausschlaggebend sind. Seit 2009 mussen alle Haltungseinrichtungen fur Legehennen in Deutschland mit einem Einstreubereich ausgestattet sein, der mit „geeignetem“ Einstreumaterial versehen ist und artgemases „Picken, Scharren und Staubbaden“ ermoglicht (Tierschutz-Nutztierhaltungsverordnung, 2006). Da ab 2012 EU-weit ahnliche Anforderungen an alle Haltungsformen fur Legehennen gestellt werden, stellt sich die Frage, welche Arten von Einstreumaterialien den in der Verordnung genannten Verhaltensanspruchen der Hennen entsprechen.

The objective of the present study was to investigate whether an arrangement of perches at two different heights within individual compartments of small group systems (back perch elevated (BE), front perch elevated (FE) or both perches heightened (FBE)) combined with an enlarged group size would increase humerus and tibia bone breaking strength and impact keel bone status. Bone strength and keel bone status of two layer strains (LSL, LB) kept in small group systems (SG 40-60 (40, 60 hens), SG 20-30 (20, 30 hens) with different perch configurations) and furnished cages (FC, 10, 20 hens, perches in standard position) were compared in two trials. Investigations were carried out in the laying months 6 and 12, comprising a total of 576 hens. When all compartments of SG 40-60 had been incorporated with perches at two different heights, humerus and tibia bone strength in LSL layers significantly increased compared to FC, whereas keel bone status was negatively impacted. Within SG 40-60, BE and FE perches significantly increased humerus strength in LSL layers compared to FBE perches. LB layers had significantly higher bone strength in groups of 20 compared to 30 hens in SG 20-30, whereas no effect of group size was detected for LSL hens. Keeping hens in SG 40-60 with modified perch positions was associated with increased bone strength but brought about the problem of inferior keel bone status.

The objective of the present study was to conduct a corresponding histological analysis of 162 macroscopically assessed keel bones (1: severe, 2: moderate, 3: slight, 4: no deformity). Four layer lines were used and hens were kept in furnished cages, small group systems (both allowing more activities due to the provision of perches) and an aviary system, which fully conformed to the EU standards. Investigations were carried out in the 3rd, 6th, 9th and 12th laying month of two experimental trials. In 97.9% of grade 4 keel bones, no histological deviations were found, whereas in keel bones manifesting deformities of grade 1 and 2, the predominant histological observation was the incidence of fracture callus material (FCM) and new bone in the form of woven bone. FCM was also detected in 50.9% of grade 3 keel bones, whereas in 40.7%, only s-shaped deviations of keel bones were found, which were related to extended pressure loading while perching activities rather than short-duration trauma. Histological analysis showed that keel bones of grade 1 and 2 were mainly attributed to traumatic origin and therefore associated with pain experience in layers. Grade 3 keel bones manifested either FCM as a result of trauma or adaptational deformities without any evidence of a preceding fracture in response to mechanical pressure loading and were most likely not associated with pain. Therefore, histological analysis was found to be a mandatory tool when evaluating grade 3 keel bones with respect to layers'welfare. Furthermore, this analysis corroborates the findings that in aviary systems deformities of keel bones are predominantly caused by painful fractures.