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The objective of this study was to analyze sexual dimorphism with regard to the bone quality of Ross 308 broilers. The relationship between carcass traits, performance and bone quality was analyzed. The effect of sex and age at slaughter was examined in four replicates, always on day 31 and day 38. The weight, length, minimum diameter and breaking strength of the tibiotarsi were measured to determine the bone quality. Female tibiotarsi were shorter, lighter and had a lower minimum diameter and breaking strength compared to male ones. The tibiotarsi of older broilers were found to show higher values in the three-point bending test. The effects on broiler performance were determined by measuring the live body weight, carcass and cut weights. The results demonstrate significant effects of the age at slaughter and the sex (p < 0.001) on all measured parameters, with males always reaching higher values compared to females. A strong correlation of performance and bone parameters could be observed between live weight and weight of the tibiotarsi on both days of data collection. Therefore, it could be beneficial to raise female and male broilers separately. However, in order to make specific recommendations for practice, further knowledge is necessary.

The equipment used in broiler breeder houses is an important factor in allowing the expression of the various behaviours of the animals, and thus realizing high welfare standards. Presently, detailed requirements for the equipment in broiler breeder houses are not specified in Germany, especially feed space and perch design allowance. One reason is that basic biometric data on broiler breeders are lacking. To close this gap, a pilot study was conducted, and birds’ width, weight, and feet were measured. Broiler breeders at 22 weeks of age (50 female and 17 male) were weighed and photographed digitally, and their body widths were calculated from the photographs. Female broiler breeders weighed 2791.80 ± 334.99 g on average and showed a body width of 20.63 ± 1.88 cm. For males, a mean of 3615.88 ± 432.46 g was measured with a body width of 21.94 ± 2.32 cm. Our examinations revealed that a trough side length of 21.00 cm per hen and 22.00 cm per cock must be provided to ensure that all broiler breeders have equal access to feed. The same dimensions should be planned as the perch length for each animal. Measurements of broiler breeders’ feet (506 female and 150 male Cobb 500) were performed at 60 weeks of age. The length of each toe and the width and length of the foot pad of both sexes were photographed and measured digitally. Female broiler breeders’ feet showed an average length of 10.14 cm, and male birds showed a length of 12.05 cm. Based on recommendations for the perch design for laying hens, round and oval perches for broiler breeders should have a circumference of at least 11.30 cm (female) or 13.40 cm (male). For angular perches, the upper contact area should have a width of 2.80 cm (female) or 3.40 cm (male). The obtained biometric data could be a useful basis for the development of legal requirements for broiler breeders.

Injurious pecking against conspecifics is a serious problem in turkey husbandry. Bloody injuries act as a trigger mechanism to induce further pecking, and timely detection and intervention can prevent massive animal welfare impairments and costly losses. Thus, the overarching aim is to develop a camera-based system to monitor the flock and detect injuries using neural networks. In a preliminary study, images of turkeys were annotated by labelling potential injuries. These were used to train a network for injury detection. Here, we applied a keypoint detection model to provide more information on animal position and indicate injury location. Therefore, seven turkey keypoints were defined, and 244 images (showing 7660 birds) were manually annotated. Two state-of-the-art approaches for pose estimation were adjusted, and their results were compared. Subsequently, a better keypoint detection model (HRNet-W48) was combined with the segmentation model for injury detection. For example, individual injuries were classified using “near tail” or “near head” labels. Summarizing, the keypoint detection showed good results and could clearly differentiate between individual animals even in crowded situations.

Studies indicate that the evaluation of animal welfare in birds may be carried out with the measurement of the stress-related hormone corticosterone in feathers. However a standardized procedure for corticosterone measurements in feathers is lacking, a validation needs to be carried out for each new species before implementation. The aim of the present study was to establish a valid method to measure corticosterone concentrations in feathers of laying hens in a precise and repeatable manner using an established and commercially available ELISA. Validation was performed with feather pools of tail and interscapular feathers of commercial Lohmann Brown laying hens. Assessment groups, consisting of 5 replicates, were created. All replicates of an assessment group were processed at the same time. Each replicate was run in 4 repetitions by ELISA. Intra-assay and interassay CV was 7.5 and 6.4%, respectively. The serial dilution showed linearity and parallelism. Examining the hormone extraction efficiency by using different methanol volumes resulted in no statistical differences (P > 0.05). Pulverized feathers showed higher corticosterone values than minced feathers (P > 0.05). Differences were shown between 2 feather types (tail vs. interscapular feathers; P 0.05). With the present study, a valid protocol, feasible for analyzing feather pools of laying hens, was developed. It may provide fundamentals for further investigations on corticosterone in feathers as a noninvasive indicator to evaluate aspects of animal welfare.

The assessment of foot pad dermatitis at slaughter is a suitable method to assess and monitor the welfare of broilers. The goals of this study were to define and validate a camera-based score that could identify macroscopic lesions of the foot pads, to identify errors, and to assess possible external factors that could influence the assessment. In the first phase 200 feet of broilers and in the second phase 500 feet were collected at slaughter, assessed visually, hung back into the evisceration line, and assessed by an automatic system. The camera score cut-off values were defined in the first (=calibration) phase. In the second (=validation) phase, the performance of diagnosis for these cut-off values was evaluated, and possible errors in the assessment of reference surface area and foot pad lesions were analyzed. The results showed that, in particular, Macro Scores 0, 2, and 3 could be identified with sufficiently high sensitivity. For Macro Score 1, the sensitivity of diagnosis was not sufficiently high in the two evaluated software versions. The current automatic assessment systems at slaughter could be adjusted to the cut-off values in order to classify foot pad dermatitis lesions. Furthermore, software updates can enhance the performance measures and lower the probability of errors.

To avoid the killing of surplus male layer chickens, dual-purpose hybrids are suggested as an alternative approach. These strains may offer additional advantages compared to conventional laying hens, for instance, a lower tendency to develop injurious pecking behavior. The aim of this study was to assess the behavior, with focus on pecking behavior, of conventional layers (Lohmann Brown plus, LB+) and dual-purpose hens (Lohmann Dual, LD). About 1,845 hens per strain with intact beaks were housed in four stable compartments in aviary systems. Video-based scan sampling of general behaviors and continuous observations of pecking behavior were carried out between 25 and 69 weeks of life. With the exception of “dustbathing” and “scratching,” hybrid × time during the laying period affected all of the observed general behaviors [F(2, 89) = 3.92–10.81, P < 0.001–0.05]. With increasing age, the LB+ hens performed more general pecking, more locomotion and less comfort and sitting behavior. General pecking and comfort behavior did not change over time in the LD hens, whereas inactive behaviors increased with age. During continuous observations, a significant hybrid x period interaction was found for all forms of pecking behavior [F(2, 89) = 4.55–14.80, P < 0.001–0.05]. The LB+ hens showed particularly more severe feather pecking (SFP), which increased with age. In contrast, SFP remained exceptionally low in the LD hens throughout production. Therefore, dual-purpose hybrids should be considered as an alternative to both avoid the killing of surplus male chickens and the development of SFP in laying hen production.

A partially (50%) perforated flooring system showed positive effects on health- and behavior-based welfare indicators without affecting production performance. Ammonia (NH3) is the most common air pollutant in poultry production, with effects on animal welfare and the environment. The objectives of animal welfare and environmental protection are often incompatible. Therefore, this study addresses the question of how a partially perforated flooring system affects NH3 emissions. According to German regulations, three fattening periods were carried out with 500 Ross 308 broilers per barn (final stocking density: 39 kg m−2). The experimental barn was equipped with an elevated perforated area in the supply section, accessible by perforated ramps. The remaining area in the experimental barn and the control barn were equipped with wood shavings (600 g m−2). Besides the different floor types, management was identical. Air temperature (Temp), relative air humidity (RH), NH3 concentration, and ventilation rate (VR) were measured continuously. Furthermore, dry matter (DM) content, pH, and litter quality were assessed. Towards the end of the fattening periods, the NH3 emission rate (ER) of the partially perforated flooring system was higher compared with that of the littered control barn (all p &lt, 0.001). This effect is mainly caused by the higher NH3 concentrations, which are promoted by the lack of compaction underneath the elevated perforated area and the increase in pH value under aerobic conditions. Nevertheless, the partially perforated flooring system offers different approaches for NH3 reduction that were previously not feasible, potentially contributing equally to animal welfare and environmental protection.

Simple Summary Laying hens, like other poultry species, can perceive ultraviolet radiation; nevertheless, standard lighting in poultry houses does not contain UV-A light (UV). However, little is known about the impact of light quality (daylight spectrum by UV-A light illumination) on plumage loss, skin injuries and the production parameters of laying hens. Presuming that offering a daylight spectrum to hens could help to prevent the loss of feathers and skin damage caused by pecking, about 92,000 Lohmann Brown hens with untrimmed beaks were kept on a farm in different barns. In order to measure effects of a daylight spectrum, half of them were kept in poultry housing illuminated with UV-A light provided in addition to standard lighting. The other half was exposed to standard lighting for poultry houses. The results indicate that separately offered UV-A light alone cannot prevent damage to the hens’ integument caused by pecking. In general, complex interactions in conjunction with UV supplementation influenced the birds’ behavior. In order to promote animal health and welfare, further research is necessary to find out more about the appropriate level of UV supplementation and suitable light sources besides optimum light spectrum. Abstract Natural light with ultraviolet spectrum (UV) influences the birds´ perception, the reflectivity of their plumage and affects bird behavior. Therefore, in Germany, laying hens kept in barns should be provided with daylight inlets. Nevertheless, lighting in laying hen houses with a UV proportion is not common practice and little is known about the detailed effects of UV-A lighting during the entire rearing and production period. The present on-farm study examines the impact of light quality on plumage loss, skin injuries and production parameters of laying hens. Therefore, about 92,000 Lohmann Brown hens with untrimmed beaks were kept on a farm in two different groups. Half of them were housed in a barn containing 10 pens illuminated by additional UV-A light (simulate “daylight spectrum”). The other half in the second barn were equally grouped, but exposed to standard lighting for poultry houses. Health, production parameters and plumage condition were monitored during rearing and production. The study results reveal that additional UV-A light is associated with the occurrence of plumage damage and cannibalistic injuries during production. In all groups, the plumage condition of the hens was intact when the hens started laying and declined with age. Therefore, complex interactions alongside UV illumination, environmental enrichment, feed and feeding strategies as well as other management factors that possibly affected both feather damage and skin injuries must also be taken into account.

In this study, a new housing system for broiler was tested. This system consisted of a slatted floor area and a littered area with the aim of improving litter quality. Two experimental broiler houses were provided. In house 1, a slatted floor was installed below the drinker and feedlines. Littered areas flanked the slatted floor. Broiler house 2 reflected conditions in commercial systems, consisting of a full littered area. Litter samples were taken at day 11 and at day 32 of the fattening period. Manure samples were taken at day 32. The total bacteria count (TBC), coliforms, Escherichia coli (E. coli) and ESBL-producing bacteria were determined. Furthermore, physical parameters (dry matter, water activity, pH) of litter and manure were measured. For statistical analyzes, a generalized linear mixed model (GLIMMIX procedure) was calculated. The floor did not show any significant effect on the bacteria content of the litter. Regarding TBC in litter, the floor showed a tendency for an effect (F = 5.42, p

Simple Summary Improving animal welfare, animal health and environmental issues is important in modern animal farming. In fattening of male turkeys, footpad dermatitis is a very frequent problem. Reducing faecal moisture is one way of controlling one source of footpad dermatitis. Therefore, in the present study, conducted under on-farm conditions, we added 0.2% enriched charcoal (known as a household remedy in therapy of diarrhoea and microbial imbalances) to the diet. Additionally, in a second experiment, the protein content of the diet was reduced by 1% from weeks 6–13 of life to slow down the growth rate and to reduce nitrogen in the litter. Three farms were visited four times during the fattening period to collect data on the birds. The charcoal-supplemented diet showed no effects on the performance of the birds or the examined health parameters. The protein-reduced and charcoal-supplemented diet did not influence the final bodyweight or the footpad status but reduced the mortality during the fattening period by 0.5%. In conclusion, enriched charcoal as 0.2% feed additive does not improve animal health, welfare or performance. Hence, a diet with temporarily reduced protein shows beneficial effects on the mortality rate and has no negative influence on the final body weight. Abstract Wet litter is the most important cause of footpad dermatitis in poultry, this in turn being a highly relevant animal-related welfare indicator. This field study was subdivided into two experiments. In Experiment 1, the standard diet was supplemented by 0.2% enriched charcoal, being a non-specific absorber and therefore might be promising in reducing faecal moisture. In Experiment 2, the experimental group received a reduced crude protein diet during weeks 6–13, combined with a 0.2% enriched charcoal supplementation. The trials were each conducted with two batches on three farms under on-farm conditions. The animals were observed at 6, 10, 14 and 18 weeks of age to collect data on body weight and different health parameters. The mortality and litter samples were analysed after slaughtering. In Experiment 1, performance and health were not affected despite higher dry matter content of the litter. In Experiment 2, the weight of birds receiving the protein-reduced diet was decreased significantly throughout the experiment. However, the slaughter weight did not differ. The mortality was reduced by 0.5% in the experimental group. Therefore, it was concluded that 0.2% of enriched charcoal is not a valuable feed-additive regarding animal health, while temporary protein reduction might have positive effects.

Roosting on elevated perches is a behavioral priority in laying hens, which is well-investigated in both experimental and commercial settings. However, little is known about perching behavior and perch requirements of alternative hybrids, such as dual-purpose hens. The aim of the present study was to gain basic knowledge on linear space requirements and perching patterns of dual-purpose hens (Lohmann Dual, LD) by comparing them to a conventional layer line (Lohmann Brown plus, LB+). About 3,700 hens per genetic strain were housed in two consecutive batches in four compartments of an aviary system with metal perches at different heights above a grid tier. As an indicator for required perching space, the body widths of a sample of individual hens was determined by image analyses. In addition, the use of five differently located perches and one cross-brace (structural element of the aviary system) was assessed by photo-based observations during the light and the dark phase. The LD hens measured an average body width of 15.95 ± 0.08 cm, and thus occupied about 7% more linear space than the LB+ hens (14.77 ± 0.08 cm body width; P < 0.05). Overall perch use was higher during the dark compared to the light phase, both in the LB+ (3.89 ± 0.08 vs. 0.79 ± 0.03 hens/m, P < 0.05) and the LD hens (2.88 ± 0.06 vs. 0.86 ± 0.03 hens/m, P < 0.05). With a maximum of 8.17 hens/m, the LB+ hens preferred to roost on the highest perches available at night. In contrast, the LD hens also rested on the lowest perches, and showed a more even use of all perches provided. During the day, the LD hens seemed to need lower perches for easy access to the feeders, whereas more LB+ hens used the higher perches, presumably to avoid threatening conspecifics. The present results show that preferences for certain perch locations differed between conventional layers and dual-purpose hens, whereas diurnal patterns of perch use were similar in both hybrids. Therefore, perches should be designed and located in an aviary system to meet the specific preferences and behavioral needs of the hybrid housed.

Access to adequate foraging material can reduce the occurrence of feather pecking and cannibalism in laying hens. Technical devices may help farmers provide enrichment material more effectively. However, research in this field is rare. On a commercial free-range farm with 15,000 laying hens (Lohmann Tradition), an enrichment device was evaluated from the 30th to the 58th week of age (LW). It ran at five time points (TP) in the afternoon and offered five grams of dried maize silage per hen per day. The numbers of hens residing in defined scratching areas (ScA) either beneath the device (ScA 1 and 3) or in a similar area without the device (ScA 2) were determined. Significantly more hens were found in ScA 1 and ScA 3 when the device was running. On average, only 6.96 (&plusmn, 7.00) hens stayed in ScA 2, whereas 31.45 (&plusmn, 5.38) and 33.83 (&plusmn, 6.16) hens stayed in ScA 1 and ScA 3, respectively. The hen numbers for ScA 1 and ScA 3 did not differ significantly, nor did the TPs have an influence on number of hens within ScA 1 and ScA 3. The number of hens beneath the device can serve as a potential indicator of the device&rsquo, s usage.

Oviposition in an appropriate nest is a behavioural priority in laying hens, and layer strains are known to differ in their patterns of nest use. However, besides oviposition, laying hens often show undesired behaviours such as aggression or gregarious nesting in colony nest boxes. The aim of the present study was to obtain basic information on the patterns of nest use and the behaviour in the nest of dual-purpose hens (Lohmann Dual, LD) by comparing them to a conventional layer strain (Lohmann Brown plus, LB+). In addition, the effect of nest location was tested for each hybrid. About 1850 untrimmed hens per genetic strain were housed in four compartments of an aviary system with colony nest boxes on the top tier. Video-based data were recorded in the first (N1) and the sixth nest (N2) in a row of nest boxes in each compartment at three times during the laying period to assess the number of hens per nest, the duration of nest visits of focal animals, and the behaviour of the hens in the nest. In general, a larger number of LD (0.87 ± 0.09–10.63 ± 0.30) than LB+ hens (0.21 ± 0.04–4.90 ± 0.24) was observed per nest box. In both hybrids, more hens were found in N1 compared to N2 (P < 0.05). Except for 43rd–48th weeks of life, the durations of nest visits did not differ between LB+ (09:51 ± 00:41–18:25 ± 00:48 mm:ss) and LD hens (07:14 ± 00:32–17:14 ± 00:32 mm:ss). However, both hybrids spent more time in N2 compared to N1 (P < 0.05). Hybrid effects (P < 0.05) were found for nearly all of the observed behaviours. In particular, LB+ hens performed more total pecking behaviour, whereas LD hens showed more piling in the nest. In the LB+ hens, nest location affected only few of the behaviours. In contrast, nest location effects were found for most of the behaviours observed in the LD hens. Particularly piling occurred to a larger extent in N1. The present results indicate that the patterns of nest use and the behaviour in the nest differed between conventional layers and dual-purpose hens. Within genetic strain, dual-purpose hens seemed to be more affected by nest location than conventional layers