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Function and organization of dustbathing in laying hens.
Abstract
Dustbathing in laying hens ( Gallus gallus domesticus ) serves to remove excessive feather lipids which accumulate and become stale during dust deprivation. In addition and probably as a consequence of lipid removal the fluffiness of the downy feather parts is enhanced. A dustbath consists of appetitive tossings and consummatory rubbings. Its function as well as its organization depend on the nature of the bathing litter. The uninterrupted performance of rubbing is crucial and predicts consistent bathing litter preferences. An increase in stale feather lipids enhances the tendency to bathe, while sham-dustbathing occurs during dust deprivation. However, during long-term deprivation sham-dustbathing develops abnormally. This seems due to intrinsic reinforcement. Long-term deprivation of functional stimulation prescribed by phylogenetical standards may result in an uncontrollable motivation to dustbathe.
... The ammonia emission from these houses is therefore mainly caused by two sources: the manure on the conveyor belts underneath the feeding, drinking and rest tiers (indicated as belt manure) and the litter-droppings mixture on the floor (indicated as litter). The manure on the belts is inaccessible for the hens; they do however, have access to the litterdroppings mixture on the floor since the litter is meant to be used by the hens as substrate for the pecking, scratching and dust bathing behaviour of the hens (Liere, 1991). ...
... The question remains whether the amount, type and composition of the litter-droppings mixture as found in aviary houses today can fulfil the demands of the hens for their dust bathing behaviour as given by Liere (1991). Control of the emission of ammonia from litter requires that it has a high dry matter content (about 90%) and is spread out in a thin layer (maximum of about 5 cm). ...
The development and practical application of welfare friendly aviary housing systems for laying hens, that generally emit more ammonia per hen than battery cage housing systems, would conflict with the Dutch policy to substantially reduce the total emission of ammonia from animal husbandry.This thesis describes the knowledge assessed by research on the ammonia emission levels of various types of aviary houses for laying hens (the inventory), the processes and factors involved in the kinetics of this ammonia emission (the characteristics) and the development of technical solutions which will lower the emission (the solutions).Housing systems for laying hens are described as and classified into battery cages and alternative systems . The waste resulting from the fresh droppings in these two types of housing systems for laying hens are classified as slurry , dry manure or litter . The degradation of nitrogenous components and the volatilisation of ammonia to the air are influenced by the manure composition, the process conditions and the local climate above the manure. Levels of emission from housing systems for laying hens vary strongly due to influencing factors that are related to the housing type , the animal , the climatisation or the management .The distribution of droppings over the two sources of emission in aviary houses, being the manure on the belts and the litter on the floor, was investigated under experimental circumstances. The effects of manure and litter handling and litter composition, and the effect of the physical parameters of the air on the emission of ammonia were quantified. The physical and chemical relationships of the volatilisation of ammonia from litter of various commercial aviary houses and the degradation of organic material in litter to ammonia were verified and demonstrated the great impact of the dry matter content of litter on the emission.A litter drying system in a Tiered Wire Floor aviary housing system was developed and the effect it had on the composition of litter and the emission of ammonia was investigated. With the knowledge acquired about the physical relationships of water evaporation from litter and the water input load to the litter through fresh droppings, it is possible to control the ammonia emission from the litter by influencing its dry matter content.
... Dustbathing is an important form of comfort behaviour in chickens, serving to remove stale feather lipids (van Liere, 1991;1992), as well as having anti-parasitic and thermoregulatory functions (Duncan et al., 1998). Chickens have a preference for dustbathing in a relatively fine particulate material such as peat, which is functionally more effective as a dustbathing substrate than commonly supplied coarser litter materials such as wood shavings (Olsson and Keeling, 2005). ...
Providing an increased variety of environmental enrichment options, with sufficient space to use them, could increase the behavioural expression of positive affective states in production animals. The goal of this study was to investigate associations between the number of different environmental enrichment options provided by commercial broiler chicken producers at different stocking densities and behavioural indicators of positive affective states in chickens. Thirty fast-growing commercial broiler chicken flocks with various numbers of environmental enrichment types (range: 0 to 4; e.g. compressed wood shavings bales, cardboard boxes, plastic crates, peat, perches, windows providing natural light) and space allowances (range: 0.058-0.076 m2/bird) were observed at approximately 28 days of age, when stocking density averaged 23.4 kg/m2. A practical transect sampling method involving 15-s 1-0 scans of successive “patches” along transects between feeders and drinkers and along the wall was used to record spontaneous occurrences of easily detected elements of play (worm-run, play-fight, wing flap, jump, run), inquisitive exploratory behaviour (ground-scratch) and comfort behaviour (vertical wing shake, as a marker of dustbathing) performed by undisturbed chickens. When summed together, these behaviours were performed by an average of 1% of the estimated number of chickens observed during the scans. There were positive associations between environmental complexity (number of environmental enrichment types provided) and the prevalence of play-fighting, ground-scratching, vertical wing shaking, and the sum of all observed behaviours. Farmers providing more types of enrichment also tended to provide more space per bird. After taking the number of enrichment types into account, providing more space per bird was associated with higher levels of jumping, running, and the sum of observed behaviours, though a lower prevalence of vertical wing shaking. In conclusion, an increased diversity of environmental enrichment types in commercial broiler houses was associated with higher expression of behavioural indicators of positive affect including social play, curiosity-driven inquisitive exploration, and comfort behaviour, while higher space allowances facilitated the expression of space-demanding locomotory play.
... A basic requirement in an enriched environment is offering an adequate amount of dry and scrapable litter, which fulfills the hens' need for dustbathing [30]. Other environmental enrichment attempts deal with the hens' need to forage by offering materials they can peck and scratch. ...
Since the abolition of beak trimming in laying hens in Germany, the importance of adequate enrichment material to help reduce feather pecking and cannibalism has grown. Here we tested an automatic enrichment device dosing grain via rough-coated pecking plates (PPs) on an organic farm, comparing its offer in four winter gardens (WGs). Winter garden (WG) 1 served as the control area without an automatic enrichment device, while WGs 2–4 offered different quantities of PPs, with WG 2 offering double the amount of PPs as WGs 3 and 4. The number of laying hens (Lohmann Brown Lite) per m² and close to the enrichment device (one hen‘s body length around) was determined using photo records. The usage behavior of the hens differed in the four WGs and with the animals’ age. Over the whole husbandry period (60 weeks), on average, 1.48 hens/m² were detected in the control area (WG 1), and a mean of 2.27 hens/m² in the enriched WGs. Compared to WG 1, the number of hens per m² was higher in WG 2 (2.43 hens/m²) and WG 3 (2.59 hens/m²) (p < 0.05), but similar in WG 4 (1.79 hens/m²). At the end of the husbandry period, fewer animals (mean of all WGs: 1.43 hens/m²) used the WGs than from beginning to the middle of the laying period (mean of all WGs: 2.05–2.15 hens/m²; p < 0.05). Our data indicate that the automatic enrichment device positively influences the animals’ use of the WG.
... Footpad dermatitis was scored from 0 to 2 on 50 random left feet per pen. The pen score was calculated as: ∑ = ((n0 × 0) + (n1 × 1) + (n2 × 2), resulting in a score of 0 to 100. that one context in which body shaking occurs is at the end of a complete dust-bathing sequence (van Liere, 1991), the higher levels of body shaking in the E treatment compared with the C treatment suggest that the enriched birds were engaging in complete dust-bathing bouts. ...
The aim of this pilot study was to investigate the effects of commercially applied environmental enrichments on behavior and lameness in broilers. Two consecutive flocks of broilers were observed at 16 days and 30 days of age to investigate differences between enriched (peat, bales of lucerne hay, and elevated platforms) and control birds with regards to behavioral activities and lameness. More running (p < .001), worm running (p = .006), play fighting (p = .015), dust bathing (p = .009), and ground pecking while standing (p < .001) were observed at 16 days than at 30 days. Across both ages, enriched birds showed more wing flapping (p = .016), wing stretching (p = .002), body shaking (p = .002), ground scratching (p < .001), and ground pecking while standing (p < .001) and lying (p = .003) compared with control birds. Even when no enrichments were close, enriched birds showed more body shaking (p = .008) and ground pecking while standing (p < 0.001) and lying (p = .010) than birds in comparable locations in control pens. There was a tendency for a lower gait score (i.e., reduced lameness) with the enriched treatment (p = .077). In conclusion, enriched birds showed higher levels of several activities compared with control birds, and demonstrated higher levels in areas where no enrichments were present.
... In addition, foraging was defined as scratching the ground with feet, pecking in the soil, or eating plant material. Dust bathing was defined as a bird sitting or lying down while fluffing dust through the plumage, accompanied by wingshaking, head rubbing, bill-raking and scratching with one leg (Van Liere, 1991). Aggression was defined as a negative interaction with other birds, which included aggressive pecks, leaps, chases, stand-offs, threats and fights (Estevez et al., 2002). ...
Broiler chickens often make limited use of the free-range area. Range use is influenced by type of shelter available. Range use may possibly be improved by a more gradual transition from the house to the range and by using dark brooders (secluded warm, dark areas in the home pen) that mimic aspects of a broody hen and possibly reduce fearfulness. The aim of this study was to assess effects of dark brooders on fearfulness, free-range use and behaviour later in life. Another aim was to test the chickens’ preference for shelter type and the effects of overhangs outside of the pop holes to provide a gradual transition to the range. Three production rounds, each with 440 Sasso broiler chickens (110/group), were completed. Chicks were housed indoors from days 0 to 25; per round, two groups had access to a dark brooder, whereas the other two groups had conventional IR lamps. Fearfulness was assessed by the open field (OF) and tonic immobility (TI) tests on days 22 to 24 on 25 chicks/group per round. Birds were then moved to four mobile houses from which they could access both grassland with artificial shelter (AS) and short rotation coppice (SRC). Two of the houses had overhangs extending from the pop holes; these were switched between the four houses weekly. Free-range use and behaviour were observed three times daily from Monday to Friday. Dark brooders did not affect results from the OF or TI test, except for jumps in the OF test which tended to occur less often in brooded chicks. Neither dark brooders (34.9% without v . 31.7% with brooder) nor overhangs (32.5% without v . 34.1% with overhangs) influenced the percentage of chickens outside. Chickens showed a clear preference for SRC, range use increased over time in SRC, and more birds ranged farther from the house in SRC. Behaviours of chickens observed outside were mainly influenced by shelter type, age of the birds and distance from the house. Locomotion tended to occur more in the presence of overhangs. Overall, these results could not confirm the hypothesis that dark brooders would decrease fearfulness and thereby increase free-range use. Overhangs also did not improve free-range use, and neither brooders nor overhangs had considerable impact on behaviour of chickens outside. Chickens clearly preferred dense natural vegetation over AS and ranged farther in it, indicating that this type of shelter is more suitable for slow-growing free-range broilers.
... In allen Kleinvolieren zusammen wurden insgesamt durchschnittlich 1639,7 8 ± 0,47 3 ± 0 6 ± 0,38 05:00 -05:50 6 ± 0,42 2 ± 0,18 4 ± 0,32 06:00 -06:50 6 ± 0,22 2 ± 0,19 4 ± 0,09 07:00 -07:50 6 ± 0,24 2 ± 0,12 4 ± 0,20 08:00 -08:50 7 ± 0,33 3 ± 0,22 5 ± 0,25 09:00 -09:50 9 ± 0,41 4 ± 0,41 5 ± 0,22 10:00 -10:50 9 ± 0,43 4 ± 0,48 5 ± 0,17 11:00 -11:50 8 ± 0,49 3 ± 0,35 5 ± 0,24 12:00 -12:50 8 ± 0,45 3 ± 0,30 5 ± 0,35 13:00 -13:50 7 ± 0,49 3 ± 0,25 5 ± 0,31 14:00 -14:50 7 ± 0,14 3 ± 0,23 4 ± 0,16 15:00 -15:50 7 ± 0,29 3 ± 0,30 4 ± 0,17 16:00 -16:50 6 ± 0,33 2 ± 0,27 4 ± 0,30 17:00 -17:50 6 ± 0,36 2 ± 0,27 4 ± 0,26 18:00 -18:50 8 ± 0,44 4 ± 0,33 5 ± 0,35 MW 7,2 ± 0,28 2,9 ± 0,19 4,6 ± 0,16 19:00 -19:50* 34 ± 0,53 11 ± 0,30 23 ± 0,36 20:00 -20:50* 34 ± 0,49 11 ± 0,29 23 ± 0,34 21:00 -21:50* 34 ± 0,46 11 ± 0,29 23 ± 0,31 22:00 -22:50* 34 ± 0,48 11 ± 0,29 22 ± 0,33 23:00 -23:50* 34 ± 0,46 11 ± 0,30 22 ± 0,30 00:00 -00:50* 34 ± 0,44 11 ± 0,30 22 ± 0,27 01:00 -01:50* 33 ± 0,35 11 ± 0,28 22 ± 0,19 02:00 -02:50* 33 ± 0,41 11 ± 0,30 22 ± 0,23 03:00 -03:50* 33 ± 0,38 11 ± 0,30 22 ± 0,18 MW* 33,7 ± 0,17 11,0 ± 0,00 23,3 ± 0,17 (VESTERGAARD, 1982b;ENGELMANN, 1984a; VAN LIERE, 1991 There was no significant difference between aviary housing and furnished cages regarding the frequentation of the laying nests during egg-laying (observation time between 4:30 am and 2 pm). The total number of eggs laid per day was distributed as follows: 10% were laid during the first hour of light, 40% after the second hour of light and 69% after the fifth hour of light. ...
... These results indicate that the missing experience with a dusty substrate may contribute to the initiation of vacuum dustbathing. It can imply that vacuum dustbathing may be sometime normal dustbathing (Liere van, 1991;Duncan and Fraser, 1998). ...
Aim of this study was to confirm the hypotheses that dustbathing behaviour of adult hens is influenced by previous manners of housing. We used 40 hens; first group was from enriched cages (EC) and second group from conventional cages (CC). The observations were performed in an experimental aviary equipped with dust bath of ash. There was a barrier – a ford with water – that prevented them from entrance into the ash bath. The observations were performed during 12 hours of light, in 5 consecutive days. During this time the ashbath was accessible with changing difficulty from 1 to 5 days. The duration of eating was higher in the EC group. The greatest difference was observed at difficulty level 3 (302 versus 207 min; P<0.001). Locomotion and standing were longer in the CC group throughout all difficulties. Durations of perching were higher in the CC group (P<0.05) and increased from difficulty 1 to difficulty 5. The length of vacuum dustbathing was shorter in the EC group than in the CC group (1.2 min vs. 4.2 min) per one hour of observation. The average length of normal dustbathing represented 6.6 min (EC) or 5.4 min per hour (CC). The results suggest that the manner of preliminary housing in enriched or conventional cages can have an influence on hen's behaviour.
... Sham dust bathing occurs in some strains (Lindberg and Nicol, 1997), whereby hens repeatedly perform wing movements on the wire floor (that would normally result in scooping dust into the plumage) without completing the dust-bathing sequence (shaking off lipid-saturated dust). This behavior is thought to indicate reduced welfare (Van Liere, 1991) or absence of pleasurable feedback (Widowski and Duncan, 2000). Certainly, sham dust bathing does not appear to return dust-bathing motivation to baseline levels (Olsson and Keeling, 2005). ...
Egg production systems have become subject to heightened levels of scrutiny. Multiple factors such as disease, skeletal and foot health, pest and parasite load, behavior, stress, affective states, nutrition, and genetics influence the level of welfare hens experience. Although the need to evaluate the influence of these factors on welfare is recognized, research is still in the early stages. We compared conventional cages, furnished cages, noncage systems, and outdoor systems. Specific attributes of each system are shown to affect welfare, and systems that have similar attributes are affected similarly. For instance, environments in which hens are exposed to litter and soil, such as noncage and outdoor systems, provide a greater opportunity for disease and parasites. The more complex the environment, the more difficult it is to clean, and the larger the group size, the more easily disease and parasites are able to spread. Environments such as conventional cages, which limit movement, can lead to osteoporosis, but environments that have increased complexity, such as noncage systems, expose hens to an increased incidence of bone fractures. More space allows for hens to perform a greater repertoire of behaviors, although some deleterious behaviors such as cannibalism and piling, which results in smothering, can occur in large groups. Less is understood about the stress that each system imposes on the hen, but it appears that each system has its unique challenges. Selective breeding for desired traits such as improved bone strength and decreased feather pecking and cannibalism may help to improve welfare. It appears that no single housing system is ideal from a hen welfare perspective. Although environmental complexity increases behavioral opportunities, it also introduces difficulties in terms of disease and pest control. In addition, environmental complexity can create opportunities for the hens to express behaviors that may be detrimental to their welfare. As a result, any attempt to evaluate the sustainability of a switch to an alternative housing system requires careful consideration of the merits and shortcomings of each housing system.
... Een stofbad duurt, mits de kip niet gestoord wordt, zo'n 20 minuten en bestaat uit een starre volgorde van een aantal gedragselementen. Voor het stofbaden genieten zand samen met turfmolm de voorkeur boven houtkrullen(Van Liere, 1991). Verondersteld wordt dat voor het stofbaden het belangrijk is dat de deeltjes van het substraat fijn moeten zijn om tussen de veren door op de huid te komen. ...
De biologische veehouderij in Nederland scoort op een aantal aspecten van dierenwelzijn aantoonbaar beter dan de gangbare veehouderij. Het rapport benoemt deze aspecten, maar geeft ook aan waar nog verbetering mogelijk is.
... leg scratches and side rubs can be performed intermittently. A bout is usually finished by the hen standing up and performing a body shake which removes the dust from the plumage (Liere, 1991). ...
Studies have shown that perching and dustbathing behaviour in birds can be affected by how and when the behaviour develops. With the increasing trend away from cages and towards keeping laying hens in larger, more complex housing systems, it is important to improve our knowledge about what chicks need to learn if they are going to be able to fully use perches and litter when these are provided to them as adults.
In the first part of this thesis the early use of perches and how this was influenced by the bird´s behaviour during the first weeks of life was investigated at the individual level. Furthermore the relationship between a bird’s spatial ability as a chick and as an adult was investigated by testing birds in two different two-dimensional spatial tests and by observing their use of perches. The aim was to investigate the degree to which birds are hatched with spatial skills or acquire these by using perches. The second part of the thesis dealt with the importance of access to an appropriate, that is to say, functional substrate for the development of dustbathing behaviour. Here comparisons of dustbathing behaviour by birds with different experiences of peat, a preferred dustbathing substrate, were carried out. In addition it was investigated whether birds that had only ever known sham dustbathing would be as motivated to get access to peat for dustbathing as birds reared and used to performing functional dustbathing.
It was found that behaviour, such as spending more time underneath the perches, related positively with early perch use and the ability to solve a two dimensional spatial test was related to use of perches in a novel situation as adult. However, the results did not shed any light on whether chicks hatched with good spatial ability or if the spatial ability mostly developed through the use of perches. Dustbathing behaviour was influenced mainly by the substrate and the birds which gained or lost access to peat changed their dustbathing behaviour according to if they dustbathed in peat or on paper. Birds dustbathing on paper performed a less coherent dustbathing behaviour with more long and short bouts than birds dustbathing on peat. Irrespective of treatment all birds were motivated to get access to peat for dustbathing. These results imply that sham dustbathing can not replace functional dustbathing for a hen. In combination, the results of this thesis confirm the importance of giving early access to litter and perches also to the young chick.
... In the wild, fowl perform dustbathing behavior at regular intervals, which is thought to maintain the amount and quality of the feather lipids and the structure of the feathers (Borchelt, Eyer, & McHenry, 1973;Van Liere & Wiepkema, 1992). Laying hens kept without dustbathing material for long periods perform a defective form of dustbathing, so-called "sham-dustbathing" (Van Liere, 1991), where they try to rub their heads in the food trough located outside the cageCNiepkema, 1985). The studies on picking in domestic bids indicated some factors that might also play a causal role feather picking and self-mutilation in caged birds. ...
There are a limited number of studies dealing with abnormal behavior in caged birds kept as pets. However, these studies demonstrate the presence of abnormal behavior in both songbirds and parrots. Ethological studies on these birds, as well as studies on domestic and zoo birds, indicate that inappropriate rearing and housing conditions may lead to behavioral abnormalities. Together these data indicate that behavioral abnormalities occur among both wild-caught and domesticated pet birds. The severity and magnitude of these abnormalities is probably underestimated, and there is a need for systematic studies on the nature, origin, variability, species-specificity, and reversibility of behavioral problems in pet birds. Abnormal behavior in caged birds may to some extent be prevented and reduced by environmental enrichment. However, most enrichment studies are anecdotal and not based on a thorough analysis of the behavioral abnormalities, which may lead to measures resulting in a reduction of symptoms rather than the underlying causes. Although it is likely that several of these problems could be reduced by modifying rearing and housing conditions, the current insights into the causal mechanisms underlying abnormal behavior of domesticated and wild-caught pet birds are limited, as are the insights into the possibilities of preventing or curing abnormal behavior.
... In experiment 1, the finding that dustbathing was performed more on the sand than on the wood shavings is in agreement with previous work in our laboratory showing that broilers prefer sand to wood shavings, paper bedding, or rice hulls for dustbathing (Shields et al., 2004). Laying hens also prefer to dustbathe in sand rather than in wood shavings or straw (Petherick and Duncan, 1989; van Liere, 1991; Sanotra et al., 1995). The results of experiment 2 were more surprising, because based on experiment 1 it was expected that broilers housed on sand bedding would show more dustbathing behavior than those housed on shavings. ...
The purpose of this study was to determine the effect of 2 different bedding types, sand and wood shavings, on the behavior of broiler chickens. In experiment 1, 6 pens were divided down the center and bedded half with sand and half with wood shavings. Male broilers (10/pen) were observed by scan sampling at 5- or 12-min intervals throughout the 6-wk growth period during the morning (between 0800 to 0900 h), afternoon (1200 to 1500 h), and night (2300 to 0600 h). There was a significant behavior x substrate x week interaction during the day (P < 0.0001) and at night (P < 0.0002). Drinking, dustbathing, preening, and sitting increased in frequency on the sand side but decreased on the wood shavings side during the day, as did resting at night. In general, broilers performed a greater proportion of their total behavioral time budget on the sand (P < 0.0001) as they aged. Broilers used the divider between the 2 bedding types to perch; perching behavior peaked during wk 4. In experiment 2, male broilers were housed in 8 pens (50 birds/pen) bedded only in sand or wood shavings. Bedding type had no effect on behavioral time budgets (P = 0.8946), although there were age-related changes in behavior on both bedding types. These results indicate that when given a choice, broilers increasingly performed many of their behaviors on sand, but if only one bedding type was provided they performed those behaviors with similar frequency on sand or wood shavings.
Birds from at least a dozen orders engage in dustbathing, including Galliformes. Dustbathing is generally considered a behavioural need for poultry. It involves a precise and orderly sequence of movements repeated over time. The most characteristic movement involves tossing the dust with the wings and undulating the body beneath the dust shower. Thus, repetitive changes in body position during dustbathing could be automatically detected through data processing of body‐mounted accelerometer recordings. The approach was tested in 13 adult male Japanese quail ( Coturnix japonica ) fitted with a body mounted triaxial accelerometer. Behaviour was video‐recorded for at least 6 h. Observations showed that when the animal lies on its left‐ or right‐side during dustbathing, the lateral (swaying) component of the acceleration vector adopts values of +1 or −1, respectively. Analysis shows that the bird repeats these shifts in body position every 25–60 s. The wavelet analysis (i.e. complex Morlet continuous wavelet transform (CWT)) detected this oscillatory behaviour within the time series as higher power values. This characteristic was used to automate the detection of dustbathing events, for which a threshold value for the maximum power value estimated was established for the corresponding range of scales between 25 and 60 s. The overall general accuracy of this classification method for dustbathing detection was 80%, with individual variations falling within the range of 66%–100%. Finally, an example of the potential of this method in the study of temporal dynamics, such as daily rhythms of dustbathing, is provided. Our results show that combining accelerometry and wavelet analysis could be useful for the assessment of intra‐ and inter‐individual variability in dustbathing dynamics over long‐term studies, even within large complex environments, such as natural habitats or breeding facilities. Moreover, this approach could open doors for future in‐depth studies exploring the relationship between dustbathing and poultry welfare.
Dustbathing is performed by many groups of birds, including Galliformes. It consists of a well-defined orderly sequence of movements. Repetitive changes in body position during dustbathing can be automatically detected through data processing of body mounted accelerometer recordings, specifically the complex Morlet continuous wavelet transform. The approach was tested in 13 adult male Japanese quail (Coturnix japonica ) fitted with a backpack containing a triaxial accelerometer and video-recorded during at least 6h. Rhythmicity (period 25-60s) in the y-axis acceleration vector is reflected as large power values, and is associated almost exclusively to dustbathing events. Thus, by implementing a threshold value we detected events automatically with an accuracy of 80% (range 66-100%). We show potential uses for characterizing temporal dynamics (e.g. daily rhythms) of dustbathing and for the assessment of intra- and inter-individual variability over long-term studies, even within large complex environments (e.g. natural environments or breeding facilities).
Summary statement
We propose a method for automatically detecting dustbathing (i.e a behavior performed by many groups of birds, including Galliformes) from triaxial accerometer recoding using a wavelet technique.
Development of quality welfare assessment protocols is a necessary step towards achieving high broiler welfare standards. Rapid growth rate and highly intensive commercial production systems have been highly associated with poor welfare indicated by mainly leg deformities, high stress levels and increased fear responses. Stress response in broilers is characterised by increased corticosterone and heterophil-to-lymphocyte ratio especially under heat stress, high light intensity, high stocking density, and an unenriched environment. Rearing environment, genotypes, high light intensity and human handling highly influence fear responses as proved during tonic immobility, open field, novel enrichment, and avoidance distance tests. Lameness which is usually visually assessed by a gait score scale remains an undisputable indicator of poor welfare in broiler production due to its effects on mobility and association with pain. Other leg problems including footpad dermatitis and hock burn also remain significant and they are highly associated with fast growth, high stocking density, poor litter quality, and poor or non-enriched production systems. Litter management and good ventilation are necessary to ensure good plumage conditions, reduction in ammonia emissions thereby promoting the well-being of broilers. Generally, broilers should be motivated and able to exhibit natural behaviours without straining including feeding, drinking, walking, and stretching thereby enhancing bird health, performance, production, and consumer satisfaction. Using a systematic approach, the important welfare parameters including stress, fear response, leg problems, plumage condition, environment, and behaviour are intensively discussed to explore the latest insights of broiler chickens’ welfare.
This study aimed to identify whether early-life conditions in broiler chickens could affect their behavior and welfare, and whether or not this was associated with an altered gut microbiome composition or diversity. Broilers were tested in a 2 x 2 factorial design with hatching conditions [home pen (OH) or at the hatchery (HH)] and enrichment (dark brooder (EE) or no brooder (NE) until 14 days of age) as factors (N = 6 per treatment combination). Microbiota composition was measured in the jejunum on days (d) 7, 14, and 35 and in pooled fecal samples on day 14. A novel environment test (NET) was performed on days 1 and 11, and the behavior was observed on days 6, 13, and 33. On day 35, composite asymmetry was determined and footpad dermatitis and hock burn were scored. In their home pen, HH showed more locomotion than OH (P = 0.05), and NE were sitting more and showed more comfort behavior than EE at all ages (P <0.001 and P = 0.001, respectively). On days 6 and 13 NE showed more eating and litter pecking while sitting, but on day 33 the opposite was found (age*enrichment: P = 0.05 and P <0.01, respectively). On days 1 and 11, HH showed more social reinstatement in the NET than OH, and EE showed more social reinstatement than NE (P <0.05). Composite asymmetry scores were lower for EE than NE (P <0.05). EE also had less footpad dermatitis and hock burn than NE (P <0.001). Within OH, NE had a more diverse fecal and jejunal microbiome compared to EE on day 14 (feces: observed richness: P = 0.052; jejunum: observed richness and Shannon: P <0.05); the principal component analysis (PCA) showed differences between NE and EE within both HH and OH in fecal samples on day 14, as well as significant differences in bacterial genera such as Lactobacillus and Lachnospiraceae (P <0.05). On day 35, PCA in jejunal samples only showed a trend (P = 0.068) for differences between NE vs. EE within the OH. In conclusion, these results suggest that especially the dark brooder affected the behavior and had a positive effect on welfare as well as affected the composition and diversity of the microbiome. Whether or not the behavior was modulated by the microbiome or vice versa remains to be investigated.
COVID-19 (coronavirus diseases 2019) has caused a high rate of anxiety, depression, alcoholism and stress in veterinary and
medical students. Prolonged closures have created a financial crisis for students. The poor quality of the online education system is
not meeting the needs of these students. Many people suffer from psychological distress due to economic losses and loneliness. This
review summarizes data from recent research papers that sheds light on the concerns of veterinary and medical students during the
COVID-19 lockdown. Suggestions for future pandemics are also summarized. Medical and veterinary education system need new
research on teaching methods, especially from a clinical point of view. In addition to improving the quality of online education in
preparation for future crises, student well-being should also be considered to mitigate social crises. Because this COVID-19 pandemic
has severely damaged the performance of students in academic and social life. More research is needed to improve the veterinary and
medical education system during any pandemic.
Commercial broiler production systems based on market initiatives to improve animal welfare beyond minimum legal requirements have emerged in several European countries. A common factor in the ‘higher welfare’ indoor systems is the application of environmental enrichment, with or without natural light, to promote locomotor activity and natural behaviours of the broiler chickens. In the current study, we evaluated the effects of a commercial enrichment programme for fast-growing indoor-housed broiler chickens, with or without natural light entering the broiler house. Enrichment materials were selected in relation to perceived minimal hygiene risk and ease of cleaning in between production cycles. Selected enrichments were a combination of wood shavings bales (1.5 bale/1000 chickens), round metal perches (2.7 m/1000 chickens) and metal chains as pecking objects (1/1000 chickens). Three treatments were studied: control (C) without enrichment and natural light, enriched (E) with enrichments as previously defined but without natural light and enriched plus natural light (EL) with enrichments as previously defined and natural light entrance. The experiment was carried out during five subsequent production cycles on one commercial broiler farm with three identical houses. EL could only be assigned to the middle house that was equipped with roof windows (light entrance area: 3% of floor space). C and E were in the two outer houses (alternated in between production cycles). Behaviour was observed during daytime at days 25 and 39 of age by scan sampling. Lameness, footpad dermatitis, hock burn, cleanliness and injuries were scored at the same ages, in addition to the response of the chickens to a novel object. Results showed that the treatments only affected broiler behaviour. E flocks showed significantly more resting as compared with EL and C. EL flocks showed significantly more walking, exploration and foraging behaviour as compared with E and C. Thus, broiler activity was highest in the EL treatment and lowest in the E treatment, with the C treatment in between. No treatment effects were found on the other welfare indicators and only a few tendencies for treatment effects were found for the novel object test, with E birds tending to be more reluctant to approach the object as compared with EL and C birds. We concluded that providing environmental enrichment and natural light-stimulated activity and natural behaviours in broiler chickens, whereas providing enrichment only seemed to have the opposite effect as compared with control flocks without enrichment.
Conventional ‘battery’ cages for laying hens without perches, nests and litter areas have been banned by law throughout the European Union since 1 January 2012. As an alternative solution, enriched cage systems were introduced. At present 11.4% of altogether 38.4 Mio. laying hens in Germany (Destatis, 2015) are kept in such systems. Our aim was to investigate how many applications of litter substrate per day are necessary to motivate laying hens to perform dust bathing behaviour, and to what extent the hens use these offered litter areas in a species-appropriate manner. Each of the two consecutive experiments was conducted for 12 months, during which 20 (experiment 1) and 40 (experiment 2) laying hens of the strains Lohmann Selected Leghorn (LSL) and Lohmann Brown Classic (LB) were housed in 10 units of the enriched cage system HÜK 125/80 (2 hens/unit [(experiment 1], 4 hens/unit [experiment 2], same strain per unit). In defined daily application frequencies from one to four times (11:00 a.m., 1:00 p.m., 3:00 p.m. and 5:00 p.m.) over the laying period, 50 g conventional feed per application were applied as litter substrate onto each 925 cm2 sized mat. The hens were recorded weekly by digital video systems. Results showed that the mean duration of dust bathing behaviour lasted 05:58min in experiment 1 and 04:59min in experiment 2. Litter application frequency had a significant effect on the dust bathing duration as well in experiment 1 (P<0.05) as experiment 2 (P<0.01). For both experiments the number of dust baths increased with the maximum number of litter applications per day and this linear trend is significant for experiment 2 (P<0.001). A high percentage of interrupted and early terminated dust bathing bouts were observed, mostly induced by a conspecific. The mean interruption duration was 00:18min for experiment 1 and 00:45min for experiment 2. The daily litter application frequency had no significant effect on the duration of interruptions for neither experiment but on the number of interruptions. According to the results of this study, litter applications at least twice a day can be recommended, and sufficiently sized dust bathing mats should be offered to laying hens housed in cage systems. Even with generously provided resources, the hens showed deficits in species-specific behaviour.
De Nederlandse biologische legpluimveehouders worden geconfronteerd met een aantal problemen. De belangrijkste daarvan zijn kannibalisme, gezondheidszorg en arbeid. In de toekomst kunnen ook de in Nederland geldende milieueisen voor knelpunten zorgen
After a prolonged experience with wood-shavings or with sand, 2 x 11 hens (Gallus gallus domesticus) were litter-deprived. Prior to the 7 to 8 day deprivation period feather samples were taken. This was repeated immediately after the deprivation had ended and right after the first bath in the familiar litter. Each feather was cut at the transition between the proximal plumulous and distal pennaceous part and lipids were extracted from separate samples, containing one type of feather parts. Hens on wood-shavings bathed 10 minutes longer after deprivation than hens on sand. This was due only to an extension of the second phase of the dustbath, which included rubbing; the first phase of tossing did not differ. In the extended phase of the wood-shavings bath the tendency to rub was lower, whereas the tendency to toss was higher than in the comparable phase of the sand bath. Thus, litter quality affected the amount of rubbings and of tossings in between. Rubbing did not effectuate a close contact between wood-shavings and the proximal integument, as wood-shavings could not be tossed into the plumage. This contrasted with baths in sand and only these baths resulted in a removal of excessive lipids from the plumulous parts. Therefore rubbing seems functionally crucial. The lipid level immediately after deprivation and the change in the quantity of lipids due to deprivation positively correlated with the amount of tossings in wood-shavings and with the amount of rubbings in sand. This indicates that the lipid condition is causally involved in dustbathing.
Leg abnormalities leading to lameness in broiler chickens are a serious welfare problem. Previous work in our laboratory demonstrated that providing broiler chickens with the opportunity to exercise by performing more natural behaviors (such as perching, walking up and down inclines and dustbathing) can improve their ability to walk normally [J.A. Mench, J.P. Garner, C. Falcone, Behavioral activity and its effects on leg problems in broiler chickens, in: H. Oester, C. Wyss (Eds.), Proceedings of the Sixth European Symposium on Poultry Welfare, World’s Poultry Science Association, Zollikofen, Switzerland, 2001, pp. 152–156]. With the long-term goal of stimulating dustbathing to improve leg condition, the aim of this study was to determine the dustbathing substrate preferred by broiler chickens. We conducted a dustbathing choice test experiment using four different bedding types (pine wood shavings, rice hulls, construction grade sand, and a recycled paper animal bedding product). Four different broiler chickens were tested each week for 6 weeks starting when the chicks were 1 week old. They were selected from two groups of broiler chickens housed in large home pens bedded with wood shavings. Selected birds were tested in smaller pens where they were deprived of all loose bedding material except during testing, which was carried out for 1h each day for three consecutive days per week. During an observation, each corner of the test pen was filled with a different bedding type, and the behavior of the focal chick recorded. Vertical wing shakes (VWS) were used as the primary measure of dustbathing activity. Broilers performed significantly more VWS per hour in sand (F3,36=13.52, P
A complexity analysis was performed on the behaviour time series of four groups of seven chickens (Gallus gallus domesticus) using the detrended fluctuation analysis (DFA). DFA quantifies the fractal-like correlation properties of behaviour sequences on short time scales (seconds) over active periods of approximately 0.5h (2050s). In this study the level of randomization of locomotor and resting sequences was related to the rearing conditions of chickens. The complexity of locomotor sequences decreased with high stress (food limitation). Adding a sand substrate increased the complexity of other activities such as perching, foraging, and resting but reduced the complexity of locomotor behaviour due to the display of sand bath behaviour. In addition, the correspondence between the complexity of behaviour sequences and age was more pronounced under control situations than under stress (food limited). Under stress it appeared that there was not enough energy to perform complex adult behaviour.
Under the hypothesis that young domestic fowl, Gallus gallus, are motivated to seek opportunities to explore novel stimuli, it was predicted that broiler chickens would show greater motivation to enter peripheral space if it contained (a) novel objects (changed daily) than if it was (b) empty or contained (c) essential resources (food, water, heat) or (d) supplementary resources (peat moss, straw bale, elevated platform). Sixteen pens, each containing 100 chickens, were set up with a home area containing essential resources and an adjacent peripheral area of the same size to which the chickens were allowed access for 3 h daily by opening a gate. There were four replicate pens on each of four treatments varying in the resources (a–d) provided in the peripheral area. During week 6, continuous video recordings showed that more chickens on the novel objects treatment ran into the peripheral area during the first 5 min after the gates were opened than did chickens on the other three treatments (P0.05). The results support the hypothesis that the chickens were motivated to seek opportunities to explore novel stimuli.
In het kader van het Plan van Aanpak Ingrepen bij Pluimvee heeft Wageningen UR Livestock Research onderzoek uitgevoerd naar het effect van het verlagen van de bezettingsdichtheid op het gedrag, veerbeschadigingen en technische resultaten bij vleeskuikenouderdieren. In dit rapport worden de resultaten van het onderzoek beschreven. Daarnaast wordt aangegeven of met het verlagen van de dierbezetting het verantwoord is om ingrepen bij mannelijke vleeskuikenouderdieren weg te laten.
We review the behavioural needs, priorities and preferences of laying hens for increased space, perching, nesting, foraging and dustbathing behaviour. Hens make full use of and may work to gain access to perches, however it is not yet known how perching ranks in comparison with otherbehaviours. Laying hens appearto have an instinctive need to perform pre-laying (nest-building) behaviour and have a strong preference for a discrete, enclosed nest site, for which they will work hard to gain access as oviposition approaches. Access to a nest site is a high-ranking priority for laying hens, preferred over food at this time. Foraging is a behavioural need, with peat, sand and wood shavings preferred substrates in choice experiments. There is no reduction in time spent foraging when a cost is imposed, nor when feed is freely available. Dustbathing is currently viewed as a behavioural need, as the extent to which hens value dustbathing is not known. Bird preferences for space are complex and confounded by interactions between group size and stocking density. There is some evidence that priority for space varies during the day and increases when the total space available to a group of birds is restricted, and that greater priority is given to space than to small group size. The presence of apparently purposeless behaviour, of high levels of aggression or redirected behaviours such as feather pecking and cannibalism are indicators that the housing system is not meeting the behavioural needs of the hens and hence is not satisfactory forbird welfare.
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Dustbathing in fowls (eg chickens, Gallus gallus) consists of tossing the litter onto and between the fluffed feathers and subsequently enclosing it by flattening the feathers. The proximal contact between litters like sand and peat, and the integument is intensified by rubbing the body. This is not the case in wood-shavings which adhere to the distal plumage after tossing; rubbings in wood-shavings are frequently interrupted by reinitiated tossings. Lipids accumulate on the feathers and become stale during dust deprivation. Only baths in sand and peat are effective in removing excessive lipids from the proximal downy feather parts. Fluffiness of the down is highest in hens on peat, intermediate on sand and lowest on wood-shavings, while the reverse is true for the plumage surface temperature of the back. Hens monitor the integumental lipid condition which becomes causally connected with bathing in the course of experiencing litter bathing effects. It is shown from the author's experimental study that hens naive of bathing in litter, and hens experienced with wood-shavings initially shifted bathing litters but finally preferred peat or sand (in that order) when peat, sand and wood-shavings were simultaneously presented Most of the hens experienced with bathing in sand did not shift to another substrate when presented with one. Recommendations are given concerning adequate dustbathing litter. A chronic deprivation of adequate litter leads to an uncontrollable condition of the lipids on the integument and an abnormal development of dustbathing. Such a deprivation therefore reduces animal welfare. Moreover, it is suggested to be costly.
Hen housing (cage or cage-free) did not impact overall abundances of northern fowl mites, Ornithonyssus sylviarum (Canestrini & Fanzago) (Acari: Macronyssidae), or chicken body lice, Menacanthus stramineus (Nitzsch) (Phthiraptera: Menoponidae). Cage-free hens received a dustbox with sand plus diatomaceous earth (DE), kaolin clay or sulphur. Weekly use varied from none to 100% of hens; 73% of hens used the dustbox at least once. Ectoparasite populations on dustbathing hens (users) were compared with those on non-user cage-free and caged hens. All materials reduced ectoparasites on user hens by 80-100% after 1 week of dustbox use. Diatomaceous earth and kaolin failed to reduce ectoparasites on non-user hens, and ectoparasites on user hens recovered after dustbox removal. A sulphur dustbox eliminated mites from all hens (including non-users) within 2-4 weeks. Residual sulphur controlled mites until the end of the experiment (up to 9 weeks), even after the dustbox was removed. Louse populations on hens using the sulphur dustbox were reduced in 1-2 weeks. Residual sulphur effects were less evident in lice, but the use of a sulphur dustbox by a higher proportion of hens extended louse control to all hens. This is the first experimental study to show that bird dustbathing in naturally and widely available dust materials (particularly kaolin) can suppress ectoparasites and thus the behaviour is probably adaptive.
Female domestic fowl, Gallus gallus domesticus, were reared from hatching with (peat-reared) or without (wire-reared) access to dry peat. When 8 weeks old, they were housed individually in cages and at 9 weeks the incidence of dustbathing on the wire cage floor was recorded (baseline). When 12 weeks old, the pullets were given one of three treatments: (1) peat was placed below the cage so that the bird could see it, but not interact with it (Below); (2) peat was placed in front of the cage so that the bird could peck and bill-rake in it (Front); or (3) peat was placed in the cage so that the bird could interact fully with it (In). The birds' responses to the peat were recorded for 1 h. During baseline, more components of dustbathing behaviour on the wire were recorded in the wire-reared pullets suggesting that birds' perception of a dustbathing substrate is influenced by previous experience. During the test, the proportion of pullets dustbathing differed between rearing conditions on In and Front but not Below. There were significant interactions between rearing and treatment on the amount of the components of dustbathing behaviour performed; there were no differences between rearing groups on Below, and peat-reared pullets performed more than wire-reared on In. These results indicate that the sight of a dusty substrate may contribute to the initiation of dustbathing. Fowl also appear to hatch with a predisposition which enables them to ‘recognize’ a substrate suitable for dustbathing.
In het kader van het onderzoek 'Alternatieve huisvesting voor leghennen' (project 1030), onderzoekt het Praktijkonderzoek Pluimveehouderij (PP) 'Het Spelderholt' de mogelijkheden en consequenties van verschillende kooiverrijkingen. Het project wordt bijna volledig door het bedrijfsleven betaald. Uitgangspunt bij dit onderzoek is niet alleen het verbeteren van het welzijn van leghennen, maar ook het zoveel mogelijk behouden van het economisch en arbeidstechnisch voordeel van de batterij. Er wordt dus gezocht naar een compromis tussen de wensen van de leghen en die van de pluimveehouder. In het onderzoek zijn verschillende aanpassingen van het bestaande batterijsysteem uitgetest en is de grote groepskooi onderzocht. Dit verslag geeft de resultaten vande vierde proefronde weer.
In de discussie rondom het vaststellen van huisvestingsnormen voor vleeskuikenouderdieren was een van de grootste knelpunten de beschikbare vloeroppervlakte per dier. Daarbij bleek een gebrek te zijn aan informatie over de relatie tussen vloeroppervlakte en welzijn. Voor het Praktijkonderzoek Pluimveehouderij 'Het Spelderholt' (PP) was dit aanleiding om een oriënterend onderzoek uit te voeren met verschil in vloeroppervlakte per dier.
Feather pecking is a serious problem in poultry housing, as it may lead to feather damage, injuries and even mortality. We tested predictions of the two prevalent hypotheses claiming that feather pecking is related to dustbathing and foraging, respectively. Forty-two groups of 30 laying hen chicks, Gallus gallus domesticuswere reared in pens with a slatted floor. Access to sand as a dustbathing substrate and straw as a foraging substrate was varied between groups. The rate of feather pecking was measured in early development up to week 7. The provision of a sand area did not prevent the chicks from developing high rates of feather pecking that caused injuries. Chicks that had access to sand from day 10 showed higher rates of feather pecking than chicks that had access to sand from day 1. The provision of straw to chicks that had developed high rates of feather pecking led to a decrease in this behaviour. Chicks that could use both sand and straw from day 1 on did not show high rates of feather pecking, and no injuries were observed in these groups. There was no significant difference in dustbathing activity between housing conditions characterized by high or low rates of feather pecking. On the other hand, foraging activity was inversely related to the rate of feather pecking, and the occurrence of feather pecking could be delayed from week 4 to week 7 by postponing procedures that led to changes in foraging behaviour. In conclusion, the results show that the presence of an appropriate substrate for dustbathing does not prevent domestic chicks from developing feather pecking. On the other hand, housing conditions that promote foraging behaviour are effective in reducing and preventing feather pecking.Copyright 1997 The Association for the Study of Animal Behaviour1997The Association for the Study of Animal Behaviour
Feather pecking and cannibalism are obviously detrimental to birds' welfare. Moreover, the introduction of alternatives to battery cage housing of laying hens is seriously hampered by these behaviours. Our experimental work reviewed here supports the hypothesis that feather pecking evolves as redirected ground pecking. Thus the main practical strategy to prevent feather pecking and cannibalism is to provide an adequate substrate throughout life, from the start of the rearing period onwards. However, no strategy guarantees that feather pecking will not develop in practical poultry husbandry and beak trimming may be required in specific cases to prevent the risk of greater welfare problems caused by cannibalism. Studies in birds showing different propensities for feather pecking may lead to a better understanding of the processes underlying feather pecking as well as providing simple procedures to select strains of birds in which the incidence of feather pecking and cannibalism is low.
List of abnormal behaviours that could be quantified as welfare indicators.
The patterning of body-care behaviour in the Herring Gull has been studied by means of: (a) qualitative observations on four individuals, and (b) application of six quantitative analytical methods on the behaviour recordings of the dominant gull (which was least influenced by other individuals). The qualitative observations led to the conclusion that in a body-care sequence a number of sharp behaviour switches occur in a fixed order; between successive switches the following
ANY authorities have suggested that dust-bathing by birds helps control ectoparasites and promotes cleanliness. However experimental verifi- cation of these ideas is meager, and the importance of dusting sites is some- times questioned by wildlife habitat managers. We noticed that Japanese Quail (Coturnix c. japonica) maintained a fairly constant daily level of dusting even when they were free of ectoparasites. This made us wonder if the dusting behavior merited more attention in wildlife habitat studies, and we designed an experiment to determine some of the effects of dusting on plumage condition. The dusting patterns of Japanese Quail, described by Benson (1965)) consist of a series of stereotyped movements that function to place dust particles on the plumage. Coturnix appear to perform complete dusting patterns without previous experience. They will dust on solid surfaces, but particulate surfaces elicit more dusting behavior. Visual clues are more important than tactile clues in stimulating dusting, and birds rarely attempt to dust on %-inch mesh wire screen. Dusting has been reported for many gallinaceous birds, including Ruffed Grouse (Bonasa umbellus) (Bump et al., 1947, Hein, 1970) ; Bobwhite (Colinus virginianus) (Stoddard, 1931) ; Scaled Quail (CaZZipepZu squumutu) (Wallmo, 1956) ; Ring-necked Pheasant (Phusiunus colchicus) (Ginn 1962) ; Chukar Partridge, (Alectoris chukar) (Bohl, 1957) ; and Turkey (Meleugris gullopuwo) (Bailey and Rinell, 1967; Mosby and Handley, 1943; Schorger, 1966; Wheeler, 1948). Ant beds, ashes, and rotted wood were most frequently listed as dusting sites, but animal burrows, road beds, and open places were also mentioned. Stoddard (1931:315) reported that lice multiplied rapidly on Bobwhite kept in shipping crates and prevented from dusting, but no other documen- tation of the idea that dusting promoted cleanliness or controlled parasites was found. Schorger (1966:177) in his book on turkeys states, "There is no proof for any of the reasons advanced for dusting. . ."
Environmental physiologists have devoted many years of study to the mechanisms of thermoregulation, but the majority of research effort in this field has been concentrated on the physiology of the control of body temperature, with emphasis on various biochemical processes involved. However, the mandatory requirement for effective thermoregulation is not only possession of a thermostat, but also the existence of an interfacing structure that can modify the flow of heat between the body core and the environment. In homeothermic birds and mammals most body heat is produced internally (endothermy) and possession of adequate insulation to retain that heat is usually provided by the skin and hair coat or feathers. In poikilothermic amphibians and reptiles most body heat is absorbed from the environment (ectothermy) and the skin serves to control rates of heat and water exchange such that favorable body temperatures are maintained. Despite the fact that the physics of heat transfer through animal insulators is not mathematically complex, it has, until recently (Mitchell 1977, Cena and Clark 1979), received less attention than a number of secondary subcutaneous mechanisms concerned in thermoregulation and in homeostasis in particular. The aim of this chapter is to review current knowledge of the biophysics of animal insulators, and to describe how their structure controls the processes of energy exchange between the internal and ambient environments.
Die Problematik der heutigen Haltungssysteme u. a. für Hühner gab Anlass zu öffentlicher Kritik. Gutachten und Empfehlungen (Brambell-Report, 1965) gingen den gesetzgeberischen Massnahmen für ein zeitgemässes Tierschutzgesetz in der Bundesrepublik Deutschland und der Schweiz voraus. Die Forderung nach Erarbeitung verhaltenswissenschaftlicher Untersuchungsmethoden und objektivierbarer Kriterien für die Beurteilung des Verhaltens von Hühnern in unterschiedlichen Haltungssystemen standen am Anfang dieses 1972 gestarteten Projektes.
Stress is viewed as a general biological and usually functional response to environmental and bodily demands. This paper summarises recent findings on interactions between environment, individual behavioral and physiological characteristics and the properties of stressors, stress states (responses) and organ systems in determining health or disease.
Since modern, intensive, husbandry systems may affect adversely both the productivity and welfare of domestic fowl, an understanding of the effects of short term stress is urgently required. Work has already shown what type of situations are liable to frustrate or frighten chickens and what the behavioral responses are likely to be.
The General Process approach to learning has sustained much criticism for its neglect of species-typical variation. Nonetheless, this approach has been fruitful in identifying many commonalities of animal learning. Pavlovian conditioning and habituation are examples of two general processes which are found in all vertebrate, and many invertebrate, species. Similarities in structure, which these learning phenomena illustrate, often suggest commonality of function. In this paper, the General Process approach is expanded to explore functional, as well as causal, questions. A major theme of this paper is that the reconciliation of learning theory and natural behavior depends upon attempts to link causal and functional analyses.
In discussing behaviour and welfare of the chicken and other domestic species, Wood-Gush (1973) and Duncan (1974) have stressed the significance of how the behaviour in question is regulated, that is the way of acting of the underlying motivational mechanism.
The effects of environmental factors on the behaviour of laying hens have been studied by several authors. Most attention has been paid to comparisons between cages and deep litter pens (Bareham 1972, Black and Hughes 1974, Hughes and Wood-Gush 1977), and the effect of flock size and density (Al-Rawi and Craig 1975, Banks and Allee 1957, Polley et al. 1974). The behaviours that have been studied include comfort behaviour, agonistic behaviour and mating behaviour. The flock sizes have mainly been small; up to about 30 hens.
In the past there has been a tendency for many ethologists to dismiss laboratory studies of learning as unnatural and irrelevant, while many students of animal learning have seen little relevance in the ethological work on the innate bases of behavior. We argue and, in a preliminary way, attempt to demonstrate that a selective synthesis of these two disciplines offers a potentially powerful perspective on learning and suggests comprehensive and testable hypotheses about the mechanisms, organization, and evolution of learning in animals under natural conditions.
Four experiments assessed the rate with which Meriones unguiculatus can remove or restore pelage lipids under different environmental temperatures and when provided or deprived of a sand substrate. The majority of hair lipids are derived from the Harderian gland, although skin sebaceous excretions may also contribute to hair lipids. Harderianectomy reduces hair lipids within 16 days. Shampooing of gerbils immediately reduces hair lipids but recovery occurs within 16 days and is facilitated by environmental temperatures of 10°C. Autogrooming of Harderian lipids is responsible for much of this recovery. Allowing animals to live on a sand substrate reduces pelage lipids, whereas depriving animals of a sand substrate increases pelage lipids. Shampooed, Harderianectomized, gerbils show minimal recovery of hair lipids, indicating that sebaceous activity cannot account for most of the pelage lipids. Pelage lipids apparently are regulated by autogrooming of Harderian lipids and by removing lipids by sandliving. Significant changes in hair lipids require from 8 to 16 days and are affected by temperature and substrate.
T HE uropygial gland of birds, otherwise known as the oil gland, preen gland or rump gland has been the subject of much discussion and in-vestigation for more than 100 years. The literature dealing with this subject is widely scattered in many journals and in many languages. The best review was written by Hou (1928b) in The Chinese Journal of Physiology-a jour-nal available in few libraries in this country. Recent papers indicate that many authors are unaware of this diverse literature. This paper was prepared to draw together the early work, review Hou' s papers, summarize the work that has appeared since, and present the results of recent experiments at the Delta Waterfowl Research Station. EARLY OBSERVATIONS Emperor Frederick II, in his monumental thirteenth century treatise on falconry (Wood and Fyfe, 1943 :71), was seemingly the first to discuss the function of the oil gland of birds. He believed that its product not only oiled the plumage but also provided a poison which was introduced by the claws of hawks and owls thus bringing quicker death to their prey. In 1678 Willugh-by studied the question of the toxic nature of the oil gland secretion but found no evidence to support Frederick' s contention. The next mention of this gland was by Tyson in 1683. In his "Anatomy of the Mexico Musk-Hog" he pointed out the similar position of the scent gland in the musk-hog (=collared peccary, Pecari angdatus) and the uropygial gland in the partridge, and suggested that they were perhaps analogous. The possibility that this gland may serve a function in providing scent remains a moot question even today.
Operant conditioning techniques were used to investigate whether access to litter can act as a positive reinforcer for hens. Access to litter did not appear to be reinforcing for hens when the operant response required of them was to peck a key (Experiments 1 and 2). When allowed access to litter, their preference for it was, however, very pronounced (Experiment 3). When the operant response was changed from key-pecking to breaking a photobeam, the hens did show that they found litter reinforcing, although only after a large number of trials (Experiment 4).
The purpose of this study was to determine the role played by functional experience in the development of the dustbathing behavior system in junglefowl. Small groups of birds were raised either in a rich environment with sand and earth, or in a poor environment with a wire mesh floor. Dustbathing and other behaviors were recorded at intervals between 2 and 9 months of age. The results showed that the form of the individual behavior patterns as well as the organization of extended bouts of dustbathing developed normally in chicks raised in a dustless environment. Further, the frequency of occurrence of dustbathing and the diurnal rhythm did not differ between groups raised in the two environments. Functional experience was necessary for the development of dust recognition, but some stimuli came to be recognized as
The components of dustbathing in 12 male and 12 female Bobwhite quail (Colinus virginianus) were described. These components form a sequence of entering the dust, pecking and scratching in the dust while standing, squatting in the dust, pecking and scratching in the dust while squatting, movements of the wings and feet to toss dust onto the ruffed plumage (dust toss), rubbing the head and side in the dust (head rub and side rub), rising, ruffling the feathers and vigorously shaking the dust out of the plumage (ruffle-shake), exiting the dust, and engaging in other behavior such as eating and drinking. Two tests were conducted at 1 day of deprivation of dust (to assess the reliability of both frequencies and sequences of components) and one test at 5 days of deprivation (to assess changes in these measures with increases in deprivation). The frequencies of seven of these components and the sequence in which the components first occurred had statistically significant reliability coefficients at both levels of deprivation. The frequencies of the components involved in driving dust into the plumage (dust toss, head rub, side rub) were significantly correlated. A statistic to measure the stability of these correlations was introduced. The frequencies of eight of the components showed significant increases with greater deprivation of dust. Male birds showed more of an increase with deprivation in the frequencies of the head and side rub components than did female birds. The sequence in which the components occurred was analyzed. The first occurrences of the dust toss, head rub, and side rub components were invariably in this order, for all of the birds tested at each deprivation level. The order of the first occurrences of the remaining components was variable. Individual components were generally repeated many times throughout a sequence; the order of each occurrence of each of the components was extremely variable between birds and tests. These results are discussed in terms of a lipid regulation model which suggests that dustbathing serves to remove lipid substances from the plumage.
Pour etudier l'importance des bains de sable sur la qualite du pelage chez le chinchilla, 16 animaux (8 mâles et 8 femelles) ont ete prives de sable pendant 25 jours apres avoir recu un shampoing. Ensuite, ils ont eu acces au sable et finalement, ils ont recu un dernier shampoing. Apres chaque periode, une meme quantite de poil a ete prelevee et analysee pour mesurer la teneur en lipide
Our previous work suggested that peripheral input from the pelage regulates sandbathing and grooming in D. merriami. To investigate this possibility we observed kangaroo rats on sandbathing substrate after four pre-test treatments. (1) Animals deprived of suitable substrate for 3 days direct equal numbers of sandbathing and grooming components to the left and right sides of the body, and the ventrum. (2) Animals treated with lanolin on one body surface direct more behaviour to the treated area and change the temporal organization of their cleaning bouts. Animals (3) treated with water, or (4) stimulated tactually show only non-significant shifts in behaviour. Results demonstrate that kangaroo rats can adjust the organization of their care of the body surface (COBS) behaviour in response to different types of peripheral input stemming from differing local conditions of the body surface.
A light and a medium hybrid strain of laying hen were tested to determine whether they differentiated between, and showed any preference for, wire and litter floors. In method 1 they were given constant access to both wire (2.5 × 2.5-cm mesh) and litter, and were observed to see how their time was partitioned. Although individual birds displayed a strong preference for spending their time on one floor or the other, the selections of the group as a whole did not differ from random. Previous experience with either wire or litter floors did affect their preference, but neither feeding, strain of bird nor time of day influenced their choice. However, 88% of eggs were laid on litter. A strain difference in roosting preference was noted: the light strain tended to roost on wire, whereas the medium strain showed a slight inclination towards litter. In method 2, in which birds were given a choice between separate cages, once the selection had been made it was irrevocable for a period of several hours, after which birds were returned to their home enclosure. In this situation six out of eight hens preferred litter; two showed no preference. Neither strain of bird nor time of day had an effect, but birds coming from cages with wire floors showed a stronger preference for litter than those from pens with litter floors. These experiments showed that an apparent preference for a particular environment can be influenced by several factors, including the method of testing used.
Removal of half of the upper and less of the lower beak of pullet chicks at 4 weeks of age resulted in less pecking at feed, fewer non-agonistic pecks of all kinds, less moving and preening, and more inactive standing and crouching during the following 3 weeks. Escape and avoidance behavior did not differ for 8–9-week-old, intact-beak and trimmed-beak pullets. Body weights, used as indirect indicators of feed intake, were initially suppressed following beak treatment, but trimmed-beak pullets were only marginally lighter by 27 weeks of age. Beak length measures taken 3 months after beak trimming indicated that regrowth had not occurred.Beak trimming was highly beneficial in reducing beak-inflicted feather loss and mortality from cannibalistic pecking in two of three commercial genetic stocks. Pullets of the third stock suffered no greater feather loss when their beaks were left intact than when they were trimmed, and mortality from cannibalistic pecking was essentially absent in this stock, regardless of beak treatment. These results indicate that either no beak trimming or less severe beak trimming is a practical possibility for poultry producers, as soon as appropriate genetic stocks are identified.
In a study of individual variation in the behaviour of tethered sows, records were made of 76 Large White × Landrace sows in their first pregnancy (gilts) tethered in stalls. Scan sampling was carried out from 07.00 to 17.00 h on 2-3 consecutive days every 5 weeks, producing sample sizes at three stages of the pregnancy (Periods 1, 2 and 3) of 48, 74 and 39, respectively. Sows were allocated to stalls at random; the influence of sows in adjacent stalls was analysed by correlation and regression analysis. Time spent standing by gilts in Period 1 correlated with that by their neighbours (n = 48, rs = 0.35, P < 0.05). Total time spent in repetitive behaviour (T; per cent of observations) also showed an association with neighbours' behaviour: it correlated most strongly with neighbours' chain chewing and manipulation (C; per cent of observations) (rs = 0.39, P < 0.01). This association was clearest in gilts on food allowances (F; kg day-1) of < 2 kg day-1 (n = 16, rs = 0.67, P < 0.01). It declined in Periods 2 and 3, which suggested that correlations were mostly caused by an influence of neighbours on the behaviour of newly tethered gilts. Regression analysis showed that food allowance and neighbours' behaviour together accounted for 50% of the observed variation and produced the equation loge T = 5.49 ( ± 0.37 ) - 3.00 ( ± 0.25 ) loge F + 0.18 ( ± 0.06 ) loge C ( RMS= 0.868, r2 = 50.4%. It seems likely that the behaviour of neighbours was an important cause of stress of newly tethered gilts. The results have implications for the design of experiments on housing and provide further evidence that tether stalls are not a suitable system of housing for pregnant sows.
A key issue in animal welfare is whether keeping animals in conditions where they cannot or do not perform behaviour typical of more naturally-kept members of their species causes them to suffer. Various measures have been used to resolve this issue. The cost an animal is prepared to pay for the opportunity to perform different behaviour can be used as a measure of the importance of that behaviour to the animal. Manipulation of time-budgets is the most reliable method of measuring such costs and of relating “deprivation” to “suffering”.
Thirty tethered sows were observed for 5 min every half-hour for 9 h spanning the two feeding periods. Activity, consisting largely of food searching behaviour and drinking, was largely restricted to two 2-h periods following each feed. Three categories of stereotyped behaviour were observed and these were closely tied to the feeding periods. Short-duration bouts of rubbing, head-waving and bar-biting occurred during food delivery, while long-duration bouts of highly stereotyped and idiosyncratic sequences of rubbing and drinking were shown by older sows immediately after feeding. Vaccuum chewing tended to occur slightly later. I suggest that frustration of feeding motivation rather than under-stimulation underlies stereotypies in pigs, and that the different forms may represent stereotype of the appetitive and consummatory phases. Aggression was rare and was not closely related to the feeding periods or to stereotypies.