Floor Eggs Research Articles

Effect of nest and floor eggs with visually clean shells on hatchability and chick quality in broiler breeders

The aim of this study is to determine whether the site of oviposition has an impact on the results of incubation of broiler hatching eggs. In order to determine this, eggs laid in the nest, eggs laid in the nest and then placed on the floor to cool and eggs laid on the floor were compared. All eggs had a visually clean shell, including eggs laid on the floor. A total of 1,800 eggs from a 59-week-old Cobb 500 parent flock were examined, divided into three groups (n = 600) with 4 replicates (150 eggs per replicate). Compared to nest eggs, floor eggs had significantly higher weight loss (p0.05), lower hatchability of set eggs and total embryonic mortality (p0.01), as well as a lower number of first grade chicks per incubator tray (p0.05). The percentage of contamination differed significantly between groups and it was the highest in floor eggs and the lowest in nest eggs (p0.01). Nest eggs placed on the floor did not differ statistically significantly from nest and floor eggs in hatchability, total mortality and number of first grade chicks per incubator tray, although these eggs achieved more favourable results compared to floor eggs (p0.05). The applied treatments did not affect the weight and length of the chicks (p0.05). This research confirmed that floor eggs, despite their clean shell, have lower hatchability and a higher percentage of contamination than nest eggs, which emphasizes the importance of maintaining hygiene in nests and preventing the appearance of floor eggs in order to ensure the maximum number of eggs suitable for incubation.

Effects of Different Non-Cage Housing Systems on the Production Performance, Serum Parameters and Intestinal Morphology of Laying Hens.

Simple SummaryWith the increased interest in animal welfare, poultry housing systems have been a concern for the last decade, and conventional cages have been replaced by non-cage systems or enriched cages. However, the environmental conditions in non-cage housing systems and their association with hens’ production performance and health have not been studied extensively. Therefore, the present study compared the indoor environmental microbial content in two different non-caged systems, namely, a plastic-net housing system and floor-litter housing system, and investigated its effects on the production performance, serum parameters and intestinal morphology of hens during the peak laying period. The results indicated that the NRS resulted in better indoor environmental air quality and ground hygiene than the LRS and enhanced the production performance, antioxidant capacity and intestinal health of hens, represented by positive changes in the laying rate, serum parameters and intestinal morphology.This study investigated the effects of plastic-net housing system (NRS) and floor-litter housing system (LRS) on the production performance, serum parameters and intestinal morphology of Shendan laying hens. A total of 1200 30-week-old hens were randomly allocated to the NRS and LRS groups, each of which included five replicates with 120 chickens in each replicate. The experiment was conducted from 32 to 40 weeks of age. Indoor airborne parameters were measured every 2 weeks, and indoor ground contamination was measured monthly. The laying rate and mortality of hens were recorded daily, and egg quality traits and serum parameters were measured every 2 weeks. At 40 weeks of age, four birds per replicate from each experimental group were selected for intestinal morphological observation. The results showed that the airborne bacteria number in the LRS was significantly higher than that in the NRS (p < 0.05) for most of the experimental period (except at 32 and 38 weeks of age), and the bacterial numbers on the surfaces of the floor and floor eggs in the LRS were approximately 10 times higher than those in the NRS (p < 0.05). Compared with the LRS, the NRS improved the laying rate (p < 0.05), reduced serum malondialdehyde (MDA) (p < 0.05) and corticosterone (CORT) concentrations and increased serum glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities, indicating favourable effects on antioxidative status. The NRS was significantly associated with an increased villus height (VH), villus height to crypt depth ratio (VCR) in the small intestine (p < 0.05) and increased VCR in the caecum (p < 0.05). Overall, the lower rate of bacterial contamination in the NRS than in the LRS indicated better environmental hygiene. The NRS enhanced the laying performance and antioxidant capacity of hens and was superior to the LRS in improving intestinal health. The current findings support the advantages of the NRS for the health and welfare of Shendan chickens during the peak laying period.

Heritability of perching behavior and its genetic relationship with incidence of floor eggs in Rhode Island Red chickens

BackgroundAs cage-free production systems become increasingly popular, behavioral traits such as nesting behavior and temperament have become more important. The objective of this study was to estimate heritabilities for frequency of perching and proportion of floor eggs and their genetic correlation in two Rhode Island Red lines.ResultsThe percent of hens observed perching tended to increase and the proportion of eggs laid on the floor tended to decrease as the test progressed. This suggests the ability of hens to learn to use nests and perches. Under the bivariate repeatability model, estimates of heritability in the two lines were 0.22 ± 0.04 and 0.07 ± 0.05 for the percent of hens perching, and 0.52 ± 0.05 and 0.45 ± 0.05 for the percent of floor eggs. Estimates of the genetic correlation between perching and floor eggs were − 0.26 ± 0.14 and − 0.19 ± 0.27 for the two lines, suggesting that, genetically, there was some tendency for hens that better use perches to also use nests; but the phenotypic correlation was close to zero. Random regression models indicated the presence of a genetic component for learning ability.ConclusionsIn conclusion, perching and tendency to lay floor eggs were shown to be a learned behavior, which stresses the importance of proper management and training of pullets and young hens. A significant genetic component was found, confirming the possibility to improve nesting behavior for cage-free systems through genetic selection.

Piling behaviour in Swiss layer flocks: Description and related factors

Smothering is a major concern within the Swiss layer industry as it can lead to a high number of animal losses. The underlying cause is piling behaviour (PB), a phenomenon where hens densely cluster together in the litter area. The aim of this study was to describe PB and events preceding PB. Furthermore, we investigated the relation of the number of piles, pile duration, and number of hens involved in a pile with time of day, flock colour, flock age, environmental factors, and flock responses to behaviour tests. We video recorded the corners of litter areas (floor) inside the barn and winter garden of 13 commercial Swiss layer flocks (5 white, 5 brown, 3 mixed layer hybrids), which were known to previously experienced problems with smothering. We recorded environmental data (air speed, spot temperature) in the observed corners and assessed flock-level responses to two behaviour tests (novel object test, stationary person test). From the video recordings, events preceding piling and piling characteristics were assessed at 20 and 30 weeks of age (w) at three times per day (0−5 h, >5-10 h, >10−15 h after lights on). Statistical analyses included generalized and linear mixed-effects models and Spearman correlations. Results showed that piling events were mainly preceded by single hen activities (77.9%) and non- hysterical mass movements (7.6%). More piles and the largest numbers of animals involved in piling occurred in white and brown flocks at >5−10 h after lights came on. The number of piles was lower and the number of involved animals and pile duration higher in 20 w compared to 30 w. No correlation was found between environmental factors and flock behaviour test responses with piling characteristics. Potential underlying causes for PB are numerous, though we provide and discuss likely mechanisms, including response facilitation, individual stimulus response, and anti-predation behaviour, based on our findings. Furthermore, PB could relate to diurnal behaviours, for example, dustbathing and hens laying floor eggs in the litter area.

Development and Optimization of a Deep-Learning-Based Egg-Collecting Robot

HighlightsAn egg-collecting robot embedded with deep-learning-based computer vision algorithms was constructed.The retrained deep-learning detector achieved &amp;gt;93% performance for detecting and locating eggs in images.The kernel sizes of 65 × 65 pixels for erosion and dilation in image processing assisted in extracting geometry features of eggs with the least remaining noises.The robot with soft grouting sponge on the gripper had 92% to 94% success in picking white and brown eggs.Abstract. Manual collection of floor eggs in cage-free hen housing systems is time-consuming and laborious. The objectives of this study were to (1) develop a robot to automatically collect floor eggs and (2) optimize the performance of recognizing and picking eggs with the robot. The robot consisted of a deep-learning-based egg detector, a robot arm, a two-finger gripper, and a hand-mounted camera. The deep-learning model, You Only Look Once (YOLO) V3, was embedded in the vision system to detect and locate eggs on a simulated litter floor in real-time. Image processing algorithms (e.g., cropping, erosion, etc.) were implemented for the detection and provided the robot with centroid coordinates, orientation, and axis lengths of the detected eggs, so that the gripper could be manipulated with an appropriate angle and opening width to grasp the detected eggs. For optimization, the YOLO V3 model was retrained with a dataset of floor eggs and achieved &amp;gt;93% performance in detecting and locating eggs. The kernel size of 65 × 65 pixels for erosion and dilation in image processing assisted in extracting the geometry features of eggs with the least remaining noises. Among the tested materials, soft grouting sponge attached to the gripper had the highest success rates for egg picking. The robot achieved 92% to 94% success in picking white and brown eggs. In sum, the developed egg-collecting robot can be relied on for picking floor eggs to assist in precision management of cage-free hen housing systems. Keywords: Floor egg, Image processing, Laying hen, Robot arm, Soft gripper, YOLO V3.

Influence of floor egg shell cleanliness and cleaning treatment on hatchability and chick quality

A total of 3,600 floor eggs from a 59-week-old Cobb 500 parent flock were collected to examine the effects of shell cleanliness and cleaning treatment on incubation results. The eggs were divided into two equal groups according to the cleanliness of the shell: eggs with a visually clean shell (clean eggs) and eggs with a dirty shell (dirty eggs). Depending on the cleaning treatment, clean and dirty eggs were divided into three equal groups: eggs that were not cleaned at all (intact), eggs that were cleaned with metal wire (scraped eggs) and eggs that were washed (washed eggs). Cleaning treatment significantly affected egg weight loss (p = 0.057). The hatchability of set eggs was under significant influence of egg cleanliness (p = 0.018), while the hatchability of fertile eggs was under significant influence of egg cleanliness (p = 0.003) and cleaning treatment (p = 0.029). Significant influence of shell cleanliness (p = 0.000) and cleaning treatment (p = 0.000) on egg contamination was also observed. Early, middle and total embryonic mortality were not significantly influenced by shell cleanliness and cleaning treatment, in contrast to late mortality which was under significant influence of egg cleanliness (p = 0.028). The number of first grade chicks per incubator tray was significantly influenced by egg cleanliness (p = 0.018). Chick weight and length were not significantly affected by shell cleanliness and cleaning treatment. The study showed that washed eggs had a higher weight loss compared to intact and scraped eggs. Dirty eggs had a lower hatchability, a higher percentage of contamination and late mortality as well as a lower number of first grade chicks per incubation tray, compared to clean eggs. Cleaning treatments did not have a significantly positive effect on the incubation results of either clean or dirty eggs. Washing treatment had a particularly negative effect on dirty eggs as they had reduced hatchability and increased contamination. The absence of a positive effect of scraping and washing treatment on the incubation results makes justification of these cleaning treatments for floor eggs doubtful.

Gregarious nesting in relation to floor eggs in broiler breeders

Gregarious nesting has often been observed in laying hens, where hens prefer to visit a nest already occupied by other hens over empty nests. This may result in overcrowding of the nests which is considered a welfare issue and, moreover, can increase the economic issue of floor eggs. This study aimed to describe gregarious nesting and spatial behavior in broiler breeders and how this relates to genetic background, fearfulness and mating behavior. Five commercially available genetic lines of broiler breeders were housed in 21 pens of 550 females and 50 males (six pens for lines 1 and 2, five pens for line 3 and two pens for lines 4 and 5) during the ages 20–60 weeks. Every 10 weeks, the plumage condition and wounds were assessed of 50 random hens per pen. Avoidance distance and novel object tests were performed to assess fearfulness at four time points. Distribution of eggs over nests was observed for 6 weeks at the onset of egg production at 26 weeks of age, and use of space was recorded at four time points, while (floor) egg production was noted daily per pen. We found differences between genetic lines over time in plumage condition and prevalence of wounds. Fear of humans was highest at the earliest age tested and did not correlate with general fearfulness as assessed by the novel object test. The distribution of eggs over nests was related to genetic background and was more uneven at the earliest age compared to later ages, and a more uneven distribution was correlated with an increased percentage of floor eggs. Distribution of birds over the litter area differed between the genetic lines, and less use of the litter area was correlated with an increased fear of humans and presence of wounds, suggesting an association with aggressive mating behavior. This difference in distribution of the birds could also explain the correlation between increased presence of wounds and decreased percentage of floor eggs. It is concluded that broiler breeders do show gregarious nesting, which is affected by genetic background. Both increased gregarious nesting and wounds are related to increased floor egg percentage, which should be studied further in broiler breeder research. Genetic selection for even use of the available nests and of the litter and slatted area would therefore support both broiler breeder welfare and performance.

Influence of a raised slatted area in front of the nest on leg health, mating behaviour and floor eggs in broiler breeders

European farms for broiler breeders often have raised slatted areas in front of the nests, but in other regions of the world no raised slatted areas are provided. This study aimed to investigate the effects of a raised slatted area on leg health, mating behaviour and floor laying behaviour. Ten groups of 33 broiler breeder hens and three males were housed in two pen types: with or without a raised slatted area in front of the nests. Each pen had one plastic and one wooden nest. Between 25 and 31 weeks of age, ten marked hens per pen were weighed and assessed weekly on foot pad dermatitis, hock burn and wounds. At the end of week 31, animals were euthanized and bone strength of the tibia and humerus of these individuals was assessed. At 24, 27 and 30 weeks of age, mating behaviour was observed for an hour per pen, noting both numbers of successful and unsuccessful copulations. The number of eggs laid in the nests and on the floor was recorded daily between 20 and 31 weeks of age. Foot pad dermatitis scores were affected by age, but not by pen type. Generally, there were only minor issues with foot pad dermatitis (scores <11 on a 0–100 scale), probably due to the young age of the hens. Body weight was not affected by pen type, while the prevalence of hock burns was too low to analyse and no difference in bone strength was found for the tibia and the humerus. Overall, mating behaviour was less frequent in pens with raised slats than in pens without raised slats (29 ± 2 vs 35 ± 3 times/h) and more frequent at 27 weeks of age than at 24 and 30 weeks of age (38 ± 1 vs 31 ± 4 and 27 ± 2 times/h). The pens with raised slats had a lower percentage of floor eggs than pens without raised slats (11.2 ± 0.4 vs 19.3 ± 0.5%). The wooden nest was preferred over the plastic nest as on average 63% of the eggs were laid in the wooden nest. This study shows that providing raised slats decreases mating behaviour and percentage of floor eggs, although its effects on leg health remain inconclusive.

Effects of edible environmental enrichments during the rearing and laying periods in a littered aviary—Part 2: physical development of pullets and performance, egg quality, and carcass composition in laying hens

Feather pecking and cannibalism are 2 major problems in laying hens' husbandry. Although additional environmental enrichment material (EM) supply is thought to lessen these problems, consistent evidences are lacking. This study examined the effects of EM supply (pecking stones and alfalfa bales) on biological performance, carcass composition, and animal losses in a littered housing system. 2,000 brown-egg and 2,000 white-egg layer hen pullets of the genetic strains Lohmann Brown classic and Lohmann Selected Leghorn classic, respectively, were reared separately in a 16-compartment aviary system until week 18. 1,320 remaining laying hens were then transferred to a 44-compartment laying stable (weeks 19–48). Both strains were tested under 4 treatment variants (n = 150–180 per strain and per variant): V1—no EM over the entire study period; V2—the rearing period with and the laying period without EM; V3—the rearing period without and the laying period with EM; V4—EM over the entire study period. Data on development, performance, egg quality, feed intake, EM consumption, animal losses, carcass composition, and economic traits were collected. Enrichment material supply during rearing (V2 and V4, both strains) was found to globally increase not only hens' relative gizzard mass (P = 0.036) but also the cracked eggs' percentage (compared with V3; P = 0.008) and to decrease the body mass in weeks 6 (P = 0.023) and 8 (P = 0.023) and the uniformity in week 16 (P = 0.011). Enrichment material provision during the laying period (V3 and V4, both strains) increased egg weights (P = 0.028) and the mean body mass (P = 0.036); however, continuous provision of EM (V4, both strains) increased the floor eggs' percentage (P = 0.019). The EM supply did not affect mortality, loss of production days, losses due to skin and toe cannibalism, or the income over feed costs. However, the income over feed and enrichment costs of V1 hens was higher by 0.55 €/hen than that of V4 hens (P = 0.022). Therefore, EM supply cannot be recommended as a measure to increase laying performance and reduce animal losses, but its positive effects on animal welfare should be considered.

High levels of contact dermatitis and decreased mobility in broiler breeders, but neither have a relationship with floor eggs

Contact dermatitis, both on the foot pads and hocks, is a well-known health issue in broilers. Less is known about contact dermatitis in broiler breeders, however, although they have many risk factors for developing leg health problems in common with broilers. This study aimed to describe the prevalence and severity of contact dermatitis during the production cycle in 5 lines of broiler breeders, investigate possible causes of contact dermatitis, and study its relationship with gait, egg production, and floor egg percentage. Five commercially available genetic lines of broiler breeders were housed in 21 pens of 550 females and 50 males from 20 to 60 wk of age. Every 10 wk litter quality, leg health measurements (foot pad dermatitis, hock burn, and gait) and body weight were assessed of 50 random hens per pen. Total number of eggs, number of eggs laid outside the nest (floor eggs), and mortality were recorded daily per pen. Prevalence of foot pad dermatitis, hock burn, and gait problems increased with age. Litter quality started to decrease at 50 wk of age. Prevalence of foot pad dermatitis was affected by litter quality, whereas genetic line had little effect. One genetic line was more prone to developing hock burns, though generally the prevalence of hock burn (13%) was much lower than that of foot pad dermatitis (74%). The percentage of broiler breeders with gait problems increased up to 24% with age, but this was not related to the prevalence of contact dermatitis. The lines differed in body weight from 32 wk of age onwards, and a higher body weight was related to lower egg production and higher cumulative mortality. The percentage of floor eggs was not related to leg health parameters or genetic line. Broiler breeders thus have similar leg health problems as broilers, but these problems are not related to the percentage of floor eggs, suggesting that other factors are involved in the undesirable behavior of floor laying.

Relative preference for wooden nests affects nesting behaviour of broiler breeders

Optimising nest design for broiler breeders has benefits for both the animals and the producers. The welfare of the hens will increase by providing preferred housing, while also reducing eggs laid outside the nests. These floor eggs cause economic losses by compromised automatic egg collection and reduced saleability and hatchability. Attractiveness of nests can involve factors such as seclusion, material and microclimate. In this study, four nest box designs were offered in a relative preference test: a plastic control nest, a plastic nest with a partition to divide the nest in two areas, a plastic nest with a ventilator underneath to create air flow inside the nest and a wooden nest. Six groups of 100 hens and 9 roosters had access to these four nests in a randomised location during the ages of 20 to 34 weeks. Nest and floor eggs were collected five days a week. Camera images from inside the nests made during the ages of 24–25 weeks and 26–27 weeks were analysed for behaviour. This included general activity, nest inspections, nest visits and social interactions. At 32 weeks of age the wooden nests were closed, and the subsequent response of the hens was monitored in terms of number of eggs. We found a clear preference in number of eggs for the wooden nest (69.3 ± 1.0%) compared to the control nest (15.1 ± 0.8%), partition nest (10.2 ± 0.5%) and the ventilator nest (5.4 ± 0.4%; p<0.0001 for difference between all nest designs). The preference for the wooden nest was also reflected in an increased time spent sitting, together with fewer nest inspections and visits per egg laid in the wooden nest. The preference for the wooden nest led to crowding, which caused an increased amount of piling, nest displacement, aggression and head shaking. The fact that the hens were willing to accept the crowded circumstances in these nests, underlines the strength of this preference. After the wooden nests were closed, the hens chose a new nest based on a combination of nest design and location. The control nest was still preferred over the other two plastic designs, although the neighbouring nests were overall preferred to the non-neighbouring nests. This study shows how the material used for nests is an important factor in suitability and should therefore be taken into account when designing nests.

Effects of litter floor access and inclusion of experienced hens in aviary housing on floor eggs, litter condition, air quality, and hen welfare

ABSTRACTWith different cage-free (CF) housing styles and management schemes, retailers have developed their own CF criteria. One highly debated aspect is if hens may be kept inside the system for part of the day—during the first few hours after lights-on. Research is lacking regarding the impacts of such a practice on hen welfare, incidence of eggs laid on the litter floor, litter condition, and air quality. This 14-mo field study was conducted to help assess such impacts. Hens (Dekalb White) in an aviary house (50,000-hen nominal capacity) were allowed to have full litter access (FLA) vs. part-time litter access (PLA) from 10:50 am to 9:00 pm, coupled with the absence or presence of experienced hens (1.5% of the population), hence a 2 × 2 factorial arrangement. The measured variables included a) incidence of floor eggs, b) percentage of birds remaining on litter floor at night, c) mortality, d) body weight (BW) and BW uniformity, e) litter condition (depth, moisture content, texture, amount removed, and bacteria concentration), f) environmental conditions, and g) welfare conditions (10 variables). Compared to FLA, PLA had a significantly lower incidence of floor eggs (1.4 ± 0.1 vs. 12.6 ± 1.1 eggs per hen housed as of 76 weeks of age (WOA), i.e., approximately 89% reduction), less manure deposition on the floor (0.53 ± 0.02 vs. 1.05 ± 0.04 kg/100 hens/d, dry basis, i.e., approximately 50% reduction), and lower ammonia concentrations due to drier litter (averaging 22% lower). Inclusion of 1.5% experienced hens in the young flock did not show benefit of reducing the incidence of floor eggs (P = 0.48). The percentage of hens remaining on the floor at night was low (< 0.01%) in all cases from 24 WOA onward. No differences were detected between FLA and PLA in hen welfare conditions, mortality, BW, BW uniformity, bacteria concentration in the litter, air temperature, or relative humidity.

Productivity, reproduction and welfare status of White Leghorn hens under cage and floor housing systems

At 18th week, a total of 450 WLH layer birds from a single hatch were randomly assigned into three treatment groups viz. individual cage, colony cage and floor housing. The performance of hens with regards to sexual maturity, hen-day egg production, egg qualities and welfare parameters in three different housing conditions up to 36 wk of age were assessed. There were significant differences (P<0.05) in the welfare status regarding feather conditions, claw length, gait scores and tonic immobility of the birds between the managemental conditions. While significantly higher (P<0.05) fearful response and time for first peck (response to novel object test) was observed in individual cage layers than the floor and colony birds. The ASM was lower in individual cages (126.76±3.64d) than floor (131.11±13.40d). The hen day egg production till 20th week was higher in colony ages than the floor. During 28–32 weeks individually caged layers had significantly higher hen day egg production (P<0.05) than the colony or floor reared layers. However, during 32–36 weeks (peak summer) the colony reared layer had more egg production (P<0.01) than the colony or floor reared layers. There were significantly difference (P<0.01) in the yolk weight, yolk index, albumin index and Haugh unit between the housing system. The yolk colour was also significantly (P<0.05) darker in individual and colony cages compared to floor reared birds. The present indicates that the WLH layers showed better welfare status when reared on floor but production performance and egg quality was superior in cage type housing system.

Evaluation of the performance of PoultryBot, an autonomous mobile robotic platform for poultry houses

Assessment of animal status, housing conditions and manually collecting floor eggs are the major daily tasks for poultry farmers. To assist the farmer in these tasks, PoultryBot, an autonomous mobile robot for use in poultry houses has been developed. In earlier research, several components of PoultryBot were discussed in detail. Here, performance of the robot is evaluated under practical conditions. For navigation, different paths were used to assess its navigation performance for various tasks, such as area sweeping and surveying close to walls. PoultryBot proved capable of navigating autonomously more than 3000 m, while avoiding obstacles and dealing with the hens present. The robustness of its navigation performance was tested by confronting PoultryBot with obstacles in different positions with respect to its path and using different settings of the navigation parameters. Both factors clearly influenced the driving behaviour of PoultryBot. For floor egg collection, detection and collection of eggs was assessed at 5 predefined egg positions lateral to the path of the robot. Over 300 eggs were tested; 46% were collected successfully, 37% was not collected successfully, and 16% were missed. The most observed failures occurred when the collection device was just next to the egg. It is thought that this problem can be solved by improving the control algorithm. The results demonstrate the validity of the PoultryBot concept and the possibility of autonomous floor egg collection in commercial poultry houses. Furthermore, they indicate that application of smart autonomous vehicles in dense animal environments is feasible.

Use of aerial perches and perches on aviary tiers by broiler breeders

Perching, especially during the night, is an innate behaviour of chickens and the provision of perches is mandatory for laying hens in multiple countries. We examined whether broiler breeders of the fast (Ross 308) and relatively slow (Sasso) growing hybrids used aerial perches (P) and perches on aviary tiers (A) during rearing and production and how it affected welfare and production in comparison to controls without perches. Two hybrids and three treatments (control, aviary, perch) were employed in a cross-factorial arrangement. Control pens consisted of litter, raised slats, group nests, two feeder and one drinker lines. Perch-pens (P) included eight wooden perches in an A-frame configuration at 25, 50, 75, 100 cm above the slats and aviary-pens (A) included four aviary tiers with wooden bars and perches arranged as a platform (70 × 450 cm) at 55, 68, 115, and 138 cm above the slats. Each treatment combination was replicated three times resulting in a total of 18 pens. Welfare parameters of hens were assessed at 45 weeks and production was monitored continuously. Both hybrids used perches increasingly with age and predominantly at night (both tests P < 0.0001). Birds in control pens perched on the grill above the feeders and drinking lines more than birds in A or P (P = 0.0002) and perches were more used in A than P pens (P = 0.002). More brood eggs were collected in control pens than in the other treatments (P = 0.02) and A-pens yielded more floor eggs (P = 0.007) than control pens and P-pens. Keel bone fractures were less frequent than in laying hens but hens in A and P pens had more keel bone fractures than hens in control pens (P = 0.02) and Sasso had more than Ross (P = 0.002). In conclusion, our results suggest that broiler breeders are highly motivated to access aerial perches or perches on aviary tiers similar to laying hens with a similar welfare problem of keel bone fractures. Perches had no influence on hatching rates but measures should be taken against floor eggs to avoid a loss of brood eggs.

Effects of different types of dark brooders on injurious pecking damage and production-related traits at rear and lay in layers

Injurious pecking (IP) remains one of the major welfare challenges in housing of laying hens worldwide due to the negative consequences it inflicts on animal welfare and economy. One potential solution to reduce IP is the use of dark brooders as the primary heat source during rearing. The objective was to investigate effects of rearing layer chicks with different management strategies and size allowances of dark brooders on IP and production-related traits during rear and lay. Groups of 100 to 103 Isa Warren chicks were reared either with one of 4 brooder types (n = 4 per treatment) or with whole-house heating (control: n = 6). Brooders were either large (54 cm2/chick) or small (72cm2/chick) and kept at a fixed height or periodically lifted. Plumage and skin condition were scored at age 6, 16, and 28 weeks. The birds were weighed at age one, 16, and 28 weeks. Data on egg production and mortality were registered daily from wk 16 until 27 wk of age. Minor differences between brooder treatments were found but with no clear trend pointing to a specific brooder treatment being superior. In contrast, major differences in IP damage were found between birds reared with or without brooders. Brooder birds had a better plumage condition throughout the experiment (P <0.001) and fewer wounds during lay (P <0.001). Mortality due to cannibalism in the brooder treatments tended to be lower during rear (P = 0.066) and was lower during lay (P <0.001). There was no treatment effect on body weight on d 7 (P = 0.48). Brooder birds laid fewer floor eggs (P <0.001) and had higher total egg production (P <0.001). We conclude that an automatic system lifting the brooders regularly may be skipped, and a size allowance of 54 cm2 per chick is sufficient, leaving the design of brooders simple and cheap. Rearing layer chicks with dark brooders can be a successful method of reducing prevalence of IP and floor eggs, whereby mortality is reduced, leading to improved welfare, egg quality, and production performance.

Feeder space affects access to the feeder, aggression, and feed conversion in laying hens in an aviary system

In laying hens, minimal requirements for feeder space (cm per bird) are based primarily on data from small groups of hens (n<10) housed in battery cages. The aim of the present study was to determine the effects of feeder space on agonistic behaviour, access to the feeder, and production in laying hens housed in an aviary system. The experiment was conducted in a quasi-commercial barn that contained 20 pens with 200 Lohmann Selected Leghorn hens housed in each. Five levels of feeder space (3.8, 6.0, 8.0, 9.0, and 10.0cm/hen) were systematically allocated to four pens each from 21 weeks of age onwards. Behavioural assessments from video recordings at 21, 32, 39, and 45 weeks of age included: aggression, jostling followed by either feeding or other behaviour, duration of feeding bouts, and the number of hens feeding from the perch above the feeder as well as simultaneously from the platform at the feeder. Production parameters were measured daily and included: egg production, floor eggs, feed disappearance, and feed conversion ratio. Our results show that more feeder space was associated with less aggression (z-value=−4.06, p<0.001) and less jostling (followed by feeding: z-value=−3.74, p<0.001; followed by other behaviour: z-value=4.24, p<0.001), as well as more simultaneous feeding from the platform at the feeder (z-value=−5.36, p<0.001) and longer feeding bouts (z-value=4.68, p<0.001). Feed disappearance (t-value=3.08, df=18, p=0.006) increased and feed conversion decreased with feeder space (t-value=2.245, df=18, p=0.038). The results indicate positive effects of increased feeder space on laying hen behaviour at the cost of relatively minor production losses. Thus, competition at the feeder decreased with increasing feeder space, allowing more birds to feed simultaneously, while feed conversion decreased only slightly. By combining measures of behaviour and production, our results can facilitate decisions on feeder space for laying hens in view of optimal trade-offs between agonistic behaviour, access to the feeder, and feed conversion.

The motivation of hens to lay eggs on the floor in non-cage systems has a heritable background

Summary Large scale egg production in cages has been practiced worldwide for many years. However, recently consumer preferences have been shifting towards eggs produced in non-cage environments. In the March 2015 issue of Poultry Science a series of papers were presented from a comparative study of three production systems: conventional cages, enriched cages and aviary systems. Among the many issues reported we paid attention to floor eggs that is of no interest in cages but plays a role in enriched cages and in particular in aviary systems. The researchers called on attention to the cost of collecting floor eggs in the aviary systems and to the fact that floor eggs were more contaminated. In the Scandinavian Selection and Crossbreeding Experiment (SSCE) in 1980, birds were kept both in cages as well as in aviary systems for 5 generations. In this presentation we demonstrate that the frequency of floor eggs over 5 generations was reduced to 55% compared to the control line, and this was statistical significant. Although not being able to estimate the heritability it can be stated that some degree of heritability exists. In the meantime an electronically controlled nest has been developed. This would make it much easier for breeders to monitor individual egg laying behaviour of laying hens kept in aviary/floor management without the laborious work when using trap nests. By doing this, a more exact estimation of the genetic basis of laying floor eggs would be possible.

Evaluation of chlorine dioxide based product as a hatchery sanitizer

Formaldehyde is commonly used to overcome contaminants introduced by hatching eggs or water supply in the hatcher cabinets. However, health risks associated with its use make economical alternatives important. This project evaluated a chlorine dioxide based product (CDBP) (0.3% concentrate) as a hatchery sanitizer in decontaminating microbial populations on the shell surface of hatching eggs (>18 d old), as well as its impact on hatchability and chick performance. Hatchers (0.20 m2) designed to hold approximately 50 eggs and equipped with circulation fans, heaters, and thermostats were used for the evaluation. For each of the 2 trials conducted, 450 hatching eggs were obtained and incubated in a common setter. Eggs used in trial 1 were floor eggs whereas in trial 2 nest eggs were used. On d 18 of incubation, eggs were removed from the setter, and viable eggs were randomly allocated to 9 hatchers. Pre-treatment egg rinse samples (10 eggs per hatcher) were collected for initial microbial analysis. Three hatchers were treated with CDBP and 3 hatchers with a formaldehyde based product (FBP). Three untreated hatchers served as control (C). Prior to hatch, 10 eggs/incubator, not previously rinsed, were used for post treatment microbial counts. The hatched chicks were reared until d 21 in floor pens with a common starter diet. For the CDBP treated eggs, hatchability and chick performance (weight gains, mortality, and FCR on d 7 and d 21) were similar to the other treatments. The application rate of CDBP evaluated in this study was not an effective antimicrobial alternative to formaldehyde for sanitizing hatching eggs in hatcher cabinets prior to hatch.

Ramps and hybrid effects on keel bone and foot pad disorders in modified aviaries for laying hens

Non-cage systems provide laying hens with considerable space allowance, perches and access to litter, thereby offering opportunities for natural species-specific behaviors. Conversely, these typical characteristics of non-cage systems also increase the risk of keel bone and foot pad disorders. The aim of this study was twofold: 1) to investigate if providing ramps between perches (housing factor) reduces keel bone and foot pad disorders and 2) to test for genetic predisposition by comparing 2 different layer hybrids. In a 2 × 2 design, 16 pens were equipped either with or without ramps between perches and nest boxes (8 pens/treatment), and housed with either 25 ISA Brown or Dekalb White birds per pen (in total 200 birds/hybrid). Keel bone injuries and foot health were repeatedly measured via palpation and visual assessment between 17 and 52 wk of age and daily egg production was recorded. The relationships between the dependent response variables (keel bone and footpad disorders, egg production) and independent factors (age, ramps, hybrid) were analyzed using generalized linear mixed models and corrected for repeated measures. Ramps reduced keel bone fractures (F1,950 = 45.80, P < 0.001), foot pad hyperkeratosis (F1,889 = 10.40, P = 0.001), foot pad dermatitis (F1,792 = 20.48, P < 0.001) and bumble foot (F1,395 = 8.52, P < 0.001) compared to pens without ramps. ISA Brown birds sustained more keel bone fractures (F1,950 = 33.26, P < 0.001), had more foot pad hyperkeratosis (F1,889 = 44.69, P < 0.001) and laid more floor eggs (F1,1883 = 438.80, P < 0.001), but had fewer keel bone deviations (F1,1473 = 6.73, P < 0.001), fewer cases of foot pad dermatitis (F1,792 = 19.84, P < 0.001) and no bumble foot as compared to Dekalb White birds. Age, housing and hybrid showed several interaction effects. Providing ramps proved to be very effective in both reducing keel bone and foot pad problems in non-cage systems. Keel bone and foot pad disorders are related to genetic predisposition. These results indicate that adaptation of the housing systems and hybrid selection may be effective measures in improving laying hen welfare.