Poor Plumage Research Articles

The effect of different housing systems on the welfare and the parasitological conditions of laying hens

In Serbia, by 2020, conventional cages will no longer be permitted and hens will be housed in furnished cages. The study was conducted during the winter season on four rearing systems of Lohman Brown hens. For welfare assessment were used indicators from the Welfare quality assessment protocol for poultry. All fecal samples for parasites were qualitatively and quantitatively examined. The results showed that each housing system had positive and negative aspects but overall, hens in cage systems had the highest prevalence of poor plumage condition (47 % and 39%). Hens in conventional cages had more skin lesions (27%) than birds in other systems. Keel bone deformation was the most present in the aviary system (56%) while comb pecking wound in a conventional cage (33%) and free-range system (50%). Hens in the non cage had the highest prevalence of foot pad disorders (32% and 40%). In furnished cages, problems occurred in hens are the lowest. Parasitological examination diagnosed four groups of endoparasites: Coccidia, Trichostrongylidae and Heterakis spp, and Capillaria spp, with a total prevalence of 64% (64/100) only in free-range system. Laying hens in cage systems have a higher expression of negative emotions in relation to the aviary and free-range system. Evidence of negative hens’ emotional condition in cage systems and negative physical condition across all housing systems, suggests that the welfare of modern hens in Serbia is impaired.

Effects of poor plumage conditions on egg production, antioxidant status and gene expression in laying hens.

The objective of this study was to investigate the effects of poor plumage conditions on production performance, antioxidant status and gene expression in laying hens. Two hundred ten 54-week-old laying hens with similar body weights were assigned into two groups based on plumage conditions (the poor plumage conditions (PPC) group and the control group). All the birds had free access to water and crumbled feed, and received the same management in step cages. Compared with hens in the control group, the hens in the PPC group consumed more feed and produced lighter eggs (P < 0.05). Hens in the PPC group showed lower serum concentrations of glutathione peroxidase and total antioxidant capacity and higher malondialdehyde content than those in the control group. The eggshell breaking strength was lower in the PPC group than in the control group (P < 0.05). The eggshell shape index and yolk colour in the PPC group were significantly higher than those in the control group. The mRNA expression level of HTR2C in the neck skin and that of IL-2 in the liver and breast muscle were higher in the PPC group than in the control group (P < 0.05). The results indicated that PPC may increase feed consumption and influence egg quality, antioxidant status and gene expression in laying hens.

A risk assessment of health, production, and resource occupancy for 4 laying hen strains across the lay cycle in a commercial-style aviary system

Different strains of commercial laying hens have been molded by varying selection pressures, impacting their production, health, and behavior. Therefore, assumptions that all laying hen strains use the given resources within aviary systems similarly and maintain equal health and performance may be false. We investigated interactions among patterns of aviary resource use by 2 strains of white and 2 strains of brown laying hens (4 units per strain, 144 hens per unit) with daily egg production, location of egg laying, keel fractures, and footpad damage across the lay cycle. Hens' distribution among resources (litter, nest, wire floor, ledge, and perch) was recorded during light and dark periods at 28, 54, and 72 wk of age. Daily egg production and location were recorded, and 20% of hens per unit were randomly selected and assessed for keel bone damage, foot health, and plumage quality. Production and health risks associated with hens' resource use were assessed using multivariable regression. During the day, more brown hens occupied wire floors, while larger numbers of white hens were on perches and litter. More brown hens were on lower-tier wire floors in the dark, while more white hens occupied top tiers. Brown hens laid more eggs outside nests, showed lower incidence of keel fractures, and had better plumage quality than white hens. White hens had higher odds of keel fractures (4.2) than brown hens. Odds of keel fractures were 3.7 and 5.7 times higher at 54 and 72 wk than at 28 wk in all strains (P ≤ 0.05). Occupying the upper tier at night increased odds of keel fractures by 5.4 times. Occupying perches was associated with lower odds of foot lesions and poor plumage quality in all strains across the lay cycle (P ≤ 0.05). Finally, white hens were associated with lower odds of non-nest laying (0.76), whereas higher nest use by brown hens resulted in higher odds of non-nest egg laying (1.56) across the lay cycle (P ≤ 0.05). Distinct strain differences in resource use in an aviary were associated with different risks to hens' production, health, and welfare.

Welfare of layers housed in small furnished cages on Danish commercial farms: the condition of keel bone, feet, plumage and skin

ABSTRACT1. An on-farm assessment of keel bone, feet, plumage and skin damage was conducted in layers in small furnished cages to evaluate welfare implications.2. Thirteen farms participated, all housing Lohmann LSL layers in systems allowing 8 or 10 hens per cage.3. Each flock was visited at three different ages: 32, 62 and 77 weeks. During each visit, 100 hens were examined for keel bone fractures and deviations, plumage damage, body wounds, foot pad lesions, bumble feet, missing toes and toe wounds.4. A deterioration with age of the condition of the plumage and keel bone was found (P < 0.001). At 77 weeks of age, 16% of the birds had poor plumage, and 43% of the birds had keel bone damage. In contrast, foot pad lesions were most prevalent at 32 weeks of age (13%), whereas the other foot injuries and body wounds remained at a relatively low level throughout the three ages examined.5. Prevention of damage to the keel bone, plumage and foot pads should therefore be considered when aiming to improve welfare of laying hens housed in small furnished cages.

Welfare Consequences of Omitting Beak Trimming in Barn Layers.

Beak trimming is used worldwide as a method of reducing the damage to feathers and skin caused by injurious pecking in laying hens. However, beak trimming also causes some welfare issues as trimming the beak results in pain and sensory loss. Due to this dilemma, there is an ongoing discussion in several European countries about whether to ban beak trimming. In this study, we investigated the welfare consequences of keeping layers with intact beaks and examined for links between injurious pecking damage and keel bone damage on an individual level. A study was conducted on 10 commercial farms housing laying hens in the barn system. Each farm participated with a flock of beak-trimmed hens (T) and a flock of non-trimmed (NT) hens that were visited around 32 and 62 weeks of age. During visits, the condition of plumage, skin, feet, and keel bone of 100 hens was assessed. Mortality was recorded by the producers. NT flocks had a lower prevalence of hens with good plumage condition around 32 weeks of age (94.1 vs. 99.6%, P < 0.001) and a higher prevalence of hens with poor plumage condition at 62 weeks of age (63.6 vs. 15.2%, P < 0.001) compared with T flocks. The prevalence of hens with keel bone deviations, with both keel bone fractures and deviations and with body wounds, was higher in NT flocks compared with T flocks at both ages (P < 0.001). Accumulated mortality from placement to end of production tended to be higher in NT flocks compared with T flocks (14.2 vs. 8.6%; P = 0.06). The prevalence of keel bone damage was higher among hens with poor plumage condition than hens with moderate/good plumage condition (31.5 vs. 22.2%; P < 0.001). Thus, omitting beak trimming had negative consequences for the condition of plumage, skin, and keel bone, and tended to increase mortality, highlighting the risk of reduced welfare when keeping layers with intact beaks. In addition, injurious pecking damage was found to be positively linked to keel bone damage. The causal relation is unknown, but we propose that fearfulness is an important factor.

Assessment of health and welfare of Austrian laying hens at slaughter demonstrates influence of husbandry system and season

ABSTRACT1. Selected health and welfare variables of laying hens from 79 flocks kept in alternative husbandry systems were assessed at the end of lay.2. Investigations were carried out on 100 hens per flock at the slaughter line and recorded as part of a novel scoring system. In addition, post-mortem investigations as well as parasitological examinations were conducted on 10 birds from each flock.3. Birds with access to free range had better plumage than birds kept in barn systems. Housing in aviaries was associated with a higher prevalence of foot pad lesions and keel bone deformations. In addition, poorer plumage, more and worse skin and foot pad lesions were documented in hens slaughtered during the winter months.4. Oophoritis and/or salpingitis were the most prevalent pathomorphological changes observed. Intestinal parasites, especially Heterakis gallinarum and Ascaridia galli, were frequent. Hens kept indoors had fewer nematoda and cestoda than those from conventional and organic free range.5. The slaughterhouse protocol allowed direct comparison of variables between flocks and specific problems to be identified in particular flocks. The results could be used to initiate detailed investigations into problematic issues on selected farms.

Feather eating and its associations with plumage damage and feathers on the floor in commercial farms of laying hens

Feather eating has been associated with feather pecking, which continues to pose economic and welfare problems in egg production. Knowledge on feather eating is limited and studies of feather eating in commercial flocks of laying hens have not been performed previously. Therefore, the main objective was to investigate feather eating and its association with plumage damage and floor feather characteristics in commercial flocks of layers in barn and organic production systems. The study was performed in 13 flocks of barn layers and 17 flocks of organic layers. Each flock was visited at around 32 and 62 weeks of age. During both visits, the plumage condition was assessed and the density of floor feathers recorded. In week 62, droppings and floor feathers were collected. Droppings were examined for presence of feather content, whereas length, downiness and pecking damage were recorded for each floor feather. In week 62, a higher prevalence of hens with poor plumage condition was found in barn (22.2%) compared with organic production systems (7.4%; P<0.001), but the prevalence of droppings with feather content did not differ between the two production systems (8.5% in barn v. 4.3% in organic; P=0.99). Our hypothesis about a positive correlation between feather eating and plumage damage was not supported as no correlation was found between the prevalence of poor plumage condition and the prevalence of droppings with feather content. However, the prevalence of pecking damaged floor feathers was positively correlated both with prevalence of droppings with feather content (P<0.05) and poor plumage condition (P<0.01), indicating a possible association between feather eating and feather pecking. In conclusion, it was confirmed that feather eating occurs on-farm, but feather eating was only found to be positively correlated to the number of floor feathers with pecking damage and not as expected to the prevalence of plumage damage. More research is needed into the sources from where feathers are selected for ingestion, that is, whether they are picked from the floor litter, plucked directly from other hens or dislodged during preening of own feathers.

Comparison of the welfare of layer hens in 4 housing systems in the UK

1. The welfare of hens in 26 flocks (6 conventional cage, 6 furnished cage, 7 barn, 7 free-range) was assessed throughout the laying period using a combination of data on physical health, physiology and injurious pecking, collected by researchers on farm and during post-mortem analysis, and information submitted by producers. 2. There was an effect of housing system on 5 of the indicators recorded by researchers: gentle feather pecks given, feather damage score, proportion of hens with feather damage, proportion of the flock using perches, and faecal corticosterone. 3. Post-mortem analysis revealed several differences between housing systems in skin damage, plumage damage to the vent and abdomen, keel protrusion, bodyweight, and the proportion of hens that were vent pecked and that had old and recent keel fractures. 4. There was an effect of housing system on 5 indicators recorded by producers: proportion of egg shells with calcification spots, proportion of egg shells with blood stains, weight of hens found dead, temporal change in the proportion of egg shells with stains, and temporal change in proportion of hens found dead. 5. Each housing system had positive and negative aspects but overall, hens in barn systems had the highest prevalence of poor plumage condition, old fractures, emaciation, abnormal egg calcification, and the highest corticosterone. Hens in conventional cages sustained more fractures at depopulation than birds in other systems. Vent pecking was most prevalent in free-range flocks. The lowest prevalence of problems occurred in hens in furnished cages. 6. Although housing system had an influence on the hens’ physical condition and physiological state, the high prevalence of emaciation, loss of plumage, fractures and evidence of stress is of concern across all housing systems, and suggests that the welfare of modern genotypes is poor.

Effect of including whole oats into pellets on performance and plumage condition in laying hens housed in conventional and furnished cages

In an experiment including 2400 layers, a diet with 40% whole oats incorporated into 3 mm pellets (experimental diet) was compared with a complete diet, also as 3 mm pellets, but containing no whole oats (control diet). These diets were examined in conventional 3-hens cages and two furnished cage systems with 8 or 16 birds per group including nest, perches and litter. The effects of diet, rearing condition and cage system on performance, plumage condition, comb lesions and rear body wounds were studied. Furthermore, the effect of feed structure on gizzard characteristics and interactions with access to litter during rearing and laying periods were examined. The hybrids LSL and Shaver 2000 were included in the experiment. Egg production was lower (P<0.05) in furnished cages than in conventional cages. No difference in plumage condition was found between diets, but a significantly poorer plumage condition (P<0.05) was observed with increasing group size. Also, the frequencies of rear body (P<0.05) wounds increased as the group sizes increased, while no such effect was observed for comb lesions. Higher (P<0.05) feed consumption was observed in furnished cages than in the conventional, causing a corresponding increase (P<0.05) in feed conversion rate (FCR). Higher (P<0.05) FCR was observed for birds fed pellets with whole oats than the control. Whole oats also increased (P<0.05) the weight of gizzard and gizzard contents. For LSL, better (P<0.05) plumage condition was found for birds reared on a deep litter floor compared to cage rearing. It was concluded that no beneficial effect of replacing high amounts of ground oats with whole oats was observed. Genotype and rearing method may interact with housing system.

Association Between Plumage Condition and Fear and Stress Levels in Five Breeds of Chickens

Duration of tonic immobility and heterophil to lymphocyte ratio (indices of fear and stress, respectively) were compared in hens having very poor or perfect plumage at 72 wk of age. Five Spanish breeds of chickens (Castellana, Andaluza, Vasca, Villafranquina, and Leonesa) were used. There were significant differences among groups in terms of tonic immobility duration and heterophil to lymphocyte ratio (P < 0.05). Very poorly feathered hens showed shorter tonic immobility (243.03+/-26.81 s) and higher leukocyte ratio (0.42+/-0.02) than did hens with a perfect plumage (322.32+/-26.81 s and 0.35+/-0.02, respectively). Differences were consistent across the breeds. Thus, hens with very poor plumage were less fearful and more stressed than hens with a perfect plumage. The results suggest that very poor plumage is associated with indicators of fearfulness and stress.

Behavioural differences between laying hen populations selected for high and low efficiency of food utilisation.

1. The effects on behaviour of selecting light-hybrid laying hens for high and low efficiency of food utilisation were investigated. Efficiency of food utilisation was measured as the proportional deviation of observed food consumption from expected food consumption. 2. Videograms of the day-time behaviour of 48 to 53-week-old individually caged hens from the F3 generation were analysed by instantaneous sampling. 3. Low-efficiency hens spent more time food-pecking, walking, pacing, and showing escape and aggressive behaviour than did high-efficiency hens. High-efficiency hens spent more than twice as much time resting and sleeping, and were never observed pacing prior to laying. 4. These differences were larger during the 2 h before laying than at other times of day. 5. Low-efficiency hens had poorer plumage, especially on the neck and the breast, and the poorer the plumage the more agitation they showed. 6. Time spent food-pecking was negatively correlated with laying frequency. 7. Differences in the occurrence of specific behaviour patterns, particularly those symptomatic of pre-laying frustration, partly explained differences in efficiency of food utilisation. Selection for higher efficiency of food utilisation might eliminate hens which are most frustrated prior to laying in cages.