Outdoor Range Research Articles

Animal welfare assessment protocol for quails reared for meat production.

It is estimated that 1.4 billion quails are reared each year for their eggs and meat, but animal welfare assessment protocols for this species have yet to be established. The objective of this study was to devise an animal welfare assessment protocol developed through a multidimensional approach that contained a number of animal-based indicators (ABIs) for quails (Coturnix japonica) reared for meat production. During 2021 and 2022, the identical auditor visited and audited 14 Spanish farms in their initial year of integration into an animal welfare certification scheme. The protocol is categorised into 4 principles and 12 criteria. The "good feeding" principle includes 6 indicators (1 ABI), "good housing" includes 10 indicators (5 ABIs), "good health" includes 12 indicators (9 ABIs), and "appropriate behaviour" contains 8 indicators (5 ABIs). The final welfare assessment is calculated at the farm level using scores from the on-farm recordings. The assessment is a step-by-step weighted sum of the scores from the various indicators, with the final score ranging between 0 and 100. The main welfare issues found on all farms were a lack of temperature and humidity records, a poor lighting pattern, and the absence of an outdoor range or access to one. To a lesser degree, it was also found that there were excessive numbers of birds per feeder, the presence of improperly functioning drinkers (i.e., not working, inadequate water flow, or dripping water), poor litter quality, and a high prevalence of birds with dirty plumage and lameness. Despite this, the farms achieved a good overall score, being classified as "enhanced" (n = 11) and "acceptable" (n = 3). The tool proved helpful in identifying specific welfare issues at the farm level and conducting benchmarking.

Space use of free-range laying hens on two outdoor ranges with different amounts of vegetation cover

Consumers’ awareness of animal welfare in farm animal husbandry – including laying hen systems – increased in the last few decades. As a result, more and more farmers in Austria changed from barn systems to free-range husbandry. However, lack of structure and protective cover in the outdoor area might cause poor use of major parts of the outdoor range. Since the ancestor of domestic chicken – the red junglefowl – inhabits dense jungle forests with manifold ground vegetation, the structural design of an outdoor area might be of high importance for laying hens. To examine this assumption, a 15×15 m grid of barrier tape was brought out on the ground of the outdoor ranges of two commercial free-range laying hen farms that differed in the amount of vegetation cover they provided. Using action cams, we took pictures of each quadrant in ten-minute intervals from 09:00 h to 21:00 h for a total of three full days. We ran GAMs for each farm separately with number of hens per quadrant and interval as dependent variable, and vegetation cover (yes/no) and position (edge/centre) of the quadrant, distance to the shed (in m), as well as temperature (in °C) as predictors. Date, time, and quadrant ID were included as smooth terms. We found a more even and widespread use of space of hens on the outdoor range with a large amount of vegetation cover (farm 1) compared to the range with a small amount of vegetation cover (farm 2). However, the number of hens decreased with increasing distance to the shed on both farms. Hens preferred edge over centre quadrants on the range of farm 1, but preferred centred quadrants with vegetation cover over those without cover on the range of farm 2. On the ranges of both farms, the number of hens decreased with increasing temperature on quadrants without vegetation cover, whereas no such effect was found for covered quadrants. These findings suggest vegetation cover to be a key factor for extensive range use, particularly in view of the expected increase in temperature due to climate change. Therefore, we recommend farmers to provide hens with highly structured outdoor ranges, not only to improve range use but also to offer hens a more species-appropriate environment, which is assumed to increase the hens’ welfare as well.

Characterization of Doppler shift in inter-satellite laser link between LEO, MEO, and GEO orbits

Over the past few decades, the development of optical wireless communications (OWC) has led to its application in a wide range of environments, including indoor, outdoor, and space. Optical carriers offer advantages such as high bandwidth, security, and directivity, making it a suitable technology for applications in radio astronomy, remote sensing, cellular networks, high-speed train communications, last-mile access, underwater/terrestrial communications, and satellite communications employing laser links. However, laser links between satellites experience Doppler shift due to their relative motion, and this effect should be taken into account from a system design perspective. This paper presents a study of the Doppler shift characterization in laser links for circular Keplerian orbits. An analytical derivation establishes the relationship between the Keplerian orbital elements and the Doppler shift in laser links. The derived equations provide a more comprehensive understanding of the impact of these orbital elements on the Doppler shift in laser links. Additionally, equations have been derived for the Doppler shift rate and the visibility window condition during satellite communication. Furthermore, we conducted a link failure analysis using simulations to evaluate the effects of the Doppler shift, also identifying the worst-case scenarios for orbits most significantly impacted by this shift. The results showed that among the six Keplerian orbital elements, the semi-major axis, inclination, and right ascension of ascending node contribute to the Doppler shift in circular orbits. While the Doppler shift impact is less significant for laser communication systems employing intensity modulation/direct detection, it can degrade the communication system performance for coherent detection. This work contributes to the effective estimation of Doppler shift from a system design perspective.

Effects of AM/PM Diets on Laying Performance, Egg Quality, and Nutrient Utilisation in Free-Range Laying Hens

Laying hen nutrient requirements change throughout the day, due to the cyclic nature of egg formation. Generally, more energy and protein are required in the morning when the albumen is deposited around the yolk, and more calcium is required in the evening when the eggshell is formed. The aim of this study was to determine if feeding laying hens diets tailored to their specific nutritional and physiological requirements throughout the day, by feeding higher levels of protein and energy in the morning and higher levels of calcium in the evening, is more beneficial than feeding one diet all day. Hy-Line Brown laying hens (n = 360) were housed in free-range floor pens (18 pens with 20 hens/pen) from 34 to 53 weeks of age (WOA). Half of the birds (n = 180, nine replicate pens) were fed a conventional layer hen diet all day (control) and the remaining birds (n = 180, nine replicate pens) were fed an AM diet from 08:00 h to 16:00 h and PM diet from 16:00 h to 08:00 h (AM/PM). From 39 WOA, hens were given access to an outdoor range from 09:00 h to 18:00 h via pop holes. Egg weight and hen-day egg production were measured daily, and feed consumption and the feed conversion ratio (FCR) were measured weekly. Hen weight and egg size uniformity were determined at 43 and 53 WOA, and egg quality was measured at 53 WOA. A total of 72 hens (4 hens/pen, 36 hens/treatment) were euthanised at 53 WOA to determine ileal apparent energy and nitrogen digestibility. A cost–benefit analysis for the study period, based on feed costs and egg mass, was calculated. Overall, the results showed that the AM/PM treatment increased egg mass by 2.15% (60.4 vs. 59.1 g/hen/day, p = 0.086) and improved feed efficiency by 8.34% (2.231 vs. 2.436 kg feed/kg egg, p = 0.030) compared with the control. A higher yolk colour score was observed in eggs from hens on the AM/PM treatment (p = 0.002), but no other significant effects of the treatments on egg quality were observed. Ileal digestible energy and digestible nitrogen coefficient were lower in hens on the AM/PM treatment compared with the control treatment (both p < 0.001). However, the AM/PM treatment was attributed to a lower feed cost to egg mass compared with the control treatment (p < 0.001). In conclusion, using an AM/PM feeding strategy was found to be economically beneficial.

Descriptive epidemiology of smothering in Australian commercial free-range layer hen farms

Since the early 2000s the practice of free-range egg production has increased in developed countries, partly driven by consumer perception that free-range housing is better for hen welfare. While poultry in free-range systems have more behavioural opportunities compared with poultry in caged systems, free-range systems are associated with greater frequencies of infectious disease, predation and ‘smothering’, a condition where birds pile on top of one another with death occurring due to suffocation. Although the frequency of smothering deaths in Australian free-range layer poultry is anecdotally high, there is a lack of empirical evidence quantifying smothering cause-specific mortality rates and identifying factors that place birds at higher risk of death from smothering.This was a prospective cohort study of poultry flocks managed by three commercial free-range layer organisations in Eastern Australia. Flocks were enrolled into the study from 1 January 2019 to 29 March 2021 and were followed until the end of lay or until the end of the study on 31 March 2022, whichever occurred first. Throughout the follow-up period flock managers provided production details for each flock and details of smothering events using custom-designed logbooks.A total of 84 flocks were enrolled in the study: 32 from Organisation 1, 35 from Organisation 2 and 17 from Organisation 3. The number of birds per flock ranged from 16,000 to 45,000. The total mortality rate was 1131 deaths per 10,000 bird-years. Smothering mortality rate across the three organisations was 183 (minimum 133, maximum 223) deaths per 10,000 bird-years at risk. Smothering accounted for around 16% (minimum 9%, maximum 22%) of all deaths.We identified no distinctive temporal pattern in daily smothering risk as a function of either the number of days since placement or calendar date. The locations of smothering events in sheds and in the outdoor range were not consistent, with relatively large numbers of smothering events occurring in specific locations for some sheds but not others. To the best of our knowledge, this study is the largest prospective study of smothering mortality in commercial free-range layer flocks conducted to date. Estimates of smothering incidence rate and how that varies within and between flocks and organisations over time provides a critically important benchmark for further investigations into this substantial area of productivity loss.

Making the most of life: environmental choice during rearing enhances the ability of laying hens to take opportunities.

The potential of aviary housing for improving laying hen (Gallus gallus domesticus) welfare will be constrained if rearing conditions limit the hens' behavioral ability to take opportunities. Incorporating theories on developmental plasticity and animal agency, this study aimed to determine: (1) whether a choice of litter and perch types during rearing would promote long-lasting changes in use of novel locations and resources, and (2) the influence of timing of choice provision. Laying hen chicks were assigned to either a "Single-choice" (one litter and perch type) or "Multi-choice" environment (four litter and perch types) during "Early" (day 1-week 4) and "Late" rearing (week 5-15). The environments were switched in half of the 16 pens in week 5, resulting in a 2 × 2 factorial design with four choice environment by period combinations. The allocation of perch and litter space was the same across all treatment combinations. In week 16, all groups were moved to standard aviary laying pens (Laying period, week 16-27). When first moved to the laying pens, hens with Multi-choice in either or both rearing periods were quicker to spread out in their pen than hens with Single-choice throughout rearing. Multi-choice in Early rearing also reduced the latency to use novel elevated structures (perches and nests) in the laying pens. Multi-choice during Late rearing increased success in finding and consuming hidden mealworms (tested in weeks 9-17) and increased the proportion of eggs laid on elevated nesting trays. Numerically, hens switched from Multi-choice to Single-choice in week 5 used the outdoor range less than hens switched from Single-choice to Multi-choice. These results support the hypothesis that offering multiple resource choices during rearing improves hens' ability to make the most of new opportunities by being more proactive in exploring and exploiting newly available resources. In different opportunity challenges, hens showed positive outcomes in response to choice during Early, Late or both stages of rearing, suggesting that best results can be obtained by offering environmental choice throughout rearing.

Visual access to an outdoor range early in life, but not environmental complexity, increases meat chicken ranging behavior

Not all chickens access an outdoor range when the opportunity is provided. This may be related to the abrupt change in environments from the stable rearing conditions to the complexity of the outdoor range. We aimed to prepare chickens to range by increasing the complexity of the indoor environment early in life with the intention to encourage range use. Mixed sex Cobb500 chickens were allocated to 1 of 3 treatment groups: visual access (VA) treatment provided VA to the outdoor range from day old via transparent pop-hole covers; environmental complexity (EC) treatment provided an artificial haybale, fan with streamers and a solid vertical barrier; Control treatment was a representative conventional environment. Chickens were given access to the outdoor range at 21 d of age. Behavior in the home pen was assessed in wk 1, 2 and 5 and individual ranging behavior was monitored through radio frequency identification (RFID) technology. The VA chickens were more active compared to EC (P = 0.006) and Control (P = 0.007) chickens and spent more time foraging than control chickens (P = 0.036) during the first week of life. More VA chickens accessed the range area compared to EC chickens (P = 0.015). VA chickens accessed the range sooner after they were first provided access and spent more time on the range than EC and control chickens (P < 0.001). Mortality was lower in the VA treatment compared to EC (P = 0.024) and control group (P = 0.002). There was evidence that VA chickens weighed less than Control and EC chickens, however results were inconsistent between age and sex. Hence, providing meat chickens with VA to an outdoor range early in life increased activity in early life, decreased latency to first access the range and increased time on the range and lowered mortality. Future work should aim to understand the mechanism behind these changes in behavior to develop recommendations for producers to implement in commercial conditions.

Associations of range use with individual behaviour, clinical welfare indicators, fear response and gastrointestinal characteristics of two laying hen hybrids

Access to an outdoor range provides laying hens with increased space and improved opportunities for performing natural behaviours. However, not all hens utilise the range to the same extent, and this may be associated with the welfare of the individual hen. The aim of this study was to assess if extent of range use was associated with several clinical welfare indicators, time budgets, measures of tonic immobility and gastrointestinal characteristics. One hundred twenty focal individuals (Bovans Brown, n = 60; Dekalb White, n = 60) randomly chosen from 12 pens of 100 hens (10 hens from each pen) were housed in accordance with the EU organic standards. Clinical welfare indicators including plumage condition, foot health, keel bone damage and body weight were assessed upon arrival at 18 weeks of age and again at 23, 28, 33 and 38 weeks of age. Over five three-day periods at corresponding weeks, hens received individual back marks for identification and behaviour was recorded by instantaneous scan sampling from 8:30–15:30 in the house and on the range. Behaviour recorded included comfort behaviours, drinking, dust bathing, eating, foraging, locomotion, nest use, pecking, perching, resting and standing. Frequency of passes through the pophole and duration of time outdoors were also determined through video observations. At 18 weeks of age a tonic immobility test was performed and number of inductions, latency to first head movement after induction and the duration of tonic immobility were recorded. At the end of the study (38 weeks of age), gastrointestinal tract morphology and contents were assessed. Individual range use varied, with hens differing in time spent on range, number of exits and consistency in these measures over time. Extent of range use was not associated with clinical welfare indicators nor fear levels as assessed by a tonic immobility test. Hens’ time budgets differed depending on where they spent most of their day, with hens utilising the range to a greater extent generally being more active (duration on range: foraging: P < 0.001, standing: P = 0.005; number of exits: locomotion: P < 0.001). Hens that utilised the range to a greater extent likely consumed more forage, as evident by the greater weight of pasture found in their crop and gizzard (P < 0.001), contributing to more developed gastrointestinal organs including the crop (duration on range: P = 0.004), gizzard (P < 0.001), and proventriculus (duration on range: P = 0.014). To conclude, the fear level and clinical welfare condition of the hens were not associated with extent of range use, unlike the time budgets and gastrointestinal characteristics.

Free range characteristics and use by chickens from two genetic lines

Abstract The free-range system improves chicken’s welfare and enriches their diet. There is little information about influence of chickens on the sward quality. The aim of the study was to identify differences in the chemical and botanical composition of the pasture sward used by chickens and to assess if frequency of chicken exits outdoors is associated with the botanical composition of the ranging areas. One hundred twenty non-beak trimmed mixed sex birds of Green-legged Partridge (GP) and Sasso line C44 (S) were used. Each pen had direct access to an individual outdoor range providing 10.5 m2 per chicken, video-recorded continuously. Vegetation coverage regarding botanical composition was determined based on botanical-weight analysis from three control plots, while range use was calculated from the video material. The data were analysed by ANOVA model in SAS software (v 9.4). Regarding chemical composition, fiber content was higher in dry matter from the control pastures. Significantly more Dactylis glomerata (L.) and Alopecurus pratensis (L.) were observed on ranges used by Sasso. The higher share (%) of weeds and grasses was at the ranges used by chickens (weeds: S:8.66 (1.42) and GP:7.61 (0.59) and grasses: S:10.36 (0.96) and GP:12.10 (0.65)) as compared to control plots (1.45 (1.34)) and 3.86 (2.97), respectively) in contrast to legumes ((S:0.01 (0.01) and GP:0.32(0.26)) and sedges (S:0.64 (0.48) and GP: 0.09 (0.06)) most present in the control plots (10.88 (1.55)). Positive association between range use frequency and proportion of Heracleum sphondylium (L.), Rumex acetosa (L.), Festuca rubra (L.), and Lolium perenne (L.) was observed for Sasso, while foe Green-legged Partridges with proportion of Armoracia rusticana (L.), Stellaria media (L.), Ranunculus repens (L.), Cirsium arvense (L.) and Rumex crispus (L.). Concluding, the sward quality of the ranging areas was affected by the presence of the chickens and it differed between genotypes. Unknown remain if birds used the pasture more frequently depending on its botanical composition or if the pasture composition depended on the frequency of its uses by the birds.

A review of thermal perception and adaptation strategies across global climate zones

Urban thermal environment is very important for human health. Although a growing number of thermal perception surveys had been conducted, the variation of thermal perception associated with background climates remains unclear. Here, we presented a global review of the quantification methods, climate differences, and adaptation strategies for outdoor and indoor thermal comfort during the last 30 years. We found that more than half of current studies were focused on temperate climate zones, particularly in China. The misunderstanding of benchmark terms and inappropriate alternative calculations lead to results bias. Although thermal comfort scale in tropical moist climate zones and thermal acceptance scale in snow and temperate climate zones tend to be refined, applied research remains limited. The results showed that tropical moist climate zones had the highest neutral temperatures while snow climate zones occupied the lowest. The neutral temperature in snow climate zones exhibited the greatest seasonal variations of 6.44 °C for outdoor environments and 6.99 °C for indoor environments. The temperate climate zones had a wider indoor thermal acceptable range while snow climate zones had a wider outdoor acceptable range. This study provides the scientific basis for optimizing management strategies in urban regions to mitigate urban thermal risks.

Surgical mask as an alternative sampling site for gunshot residue analysis

Gunshot residue (GSR) has been identified in the oro-nasal cavities and in various areas of the face. However, there is no study in the literature about the outcome of the analysis if the mouth and nose are covered with a mask. The purpose of this study is to experimentally ascertain whether GSR detection can be made on surgical masks. Twelve civilians wearing facemasks were divided into six groups of two, each consisting of a shooter and an accompanying person. A single shot was fired by the mask wearing shooters of all six groups in an outdoor and indoor shooting range. The inner surface, outer surface, and strap of the mask were the three areas where we investigated for the presence of GSR. GSR particle counts of the shooter were higher than those of accompanying person. Analysis after outdoor range shootings yielded fewer particles than indoor range shootings. The most particles were detected on the outer surface of the masks, and the least on the inner surface. All analyzes performed on the shooters' mask revealed significantly higher number of particles compared to accompanying persons. The results showed a significant difference in the quantity of GSR particles identified, which could aid in distinguishing between the shooter and the accompanying person. The outer surface of the mask has been determined to be the most useful sampling location in this regard, as it is the sample where the difference is most prominent.

Behavioural indicators of range use in four broiler strains

Free-range systems provide an outdoor range for broilers to give them the possibility to express a higher frequency and a wider range of behaviours, such as exploration, compared with those raised indoors. Greater variability in outdoor range use between individuals of the same flock is often reported. Individual variation in range use may result from differences in early-life behaviour or genetic background. Understanding how early-life behaviour influences range use may provide opportunities to enhance and predict range use. Previous studies have shown that range use could be influenced by the animal’s personality traits such as social motivation, boldness and foraging motivation. Therefore, this study investigated personality traits in several broiler strains, namely Hubbard JA757, Hubbard S757N, White Bresse and a dual-purpose strain; we examined the latter as it represents a potential solution to the ban of 1-day-old chick culling. The present study also investigated early-life behaviours, before range access, of range use to identify and assess the stability of these early-life indicators among the four broiler strains. For that purpose, we recorded the behaviour and range use of 100 male chickens per strain, both in the barn and during individual tests, before and after range access. We examined which behaviours were time consistent, whether early-life behaviours were influenced by genetic variation and whether early-life behavioural indicators predicted range use regardless of genetic variation. There was a significant (p < 0.001) difference between strains in several early-life behaviours, including the time spent resting or standing. Range use was time consistent regardless of the strain as our range use indicator followed a high-quality linear regression model (R² > 0.7) for 82–99% of the individuals depending on their strain. Besides, time consistency of social motivation and boldness seemed to depend on the strain. Even though foraging showed low (rho = 0.2–0.4) positive correlations with range use in three of the four studied strains, there were no significant and strong correlations in the four studied strains between early-life behavioural indicators and range use. In conclusion, our results show that the link between chick behaviour (before range access) and range use can be modulated by the bird’s strain. It is crucial to consider all these different factors to better understand how range use varies within and between flocks.

Welfare of broilers on farm.

This Scientific Opinion considers the welfare of domestic fowl (Gallus gallus) related to the production of meat (broilers) and includes the keeping of day-old chicks, broiler breeders, and broiler chickens. Currently used husbandry systems in the EU are described. Overall, 19 highly relevant welfare consequences (WCs) were identified based on severity, duration and frequency of occurrence: 'bone lesions', 'cold stress', 'gastro-enteric disorders', 'group stress', 'handling stress', 'heat stress', 'isolation stress', 'inability to perform comfort behaviour', 'inability to perform exploratory or foraging behaviour', 'inability to avoid unwanted sexual behaviour', 'locomotory disorders', 'prolonged hunger', 'prolonged thirst', 'predation stress', 'restriction of movement', 'resting problems', 'sensory under- and overstimulation', 'soft tissue and integument damage' and 'umbilical disorders'. These WCs and their animal-based measures (ABMs) that can identify them are described in detail. A variety of hazards related to the different husbandry systems were identified as well as ABMs for assessing the different WCs. Measures to prevent or correct the hazards and/or mitigate each of the WCs are listed. Recommendations are provided on quantitative or qualitative criteria to answer specific questions on the welfare of broilers and related to genetic selection, temperature, feed and water restriction, use of cages, light, air quality and mutilations in breeders such as beak trimming, de-toeing and comb dubbing. In addition, minimal requirements (e.g. stocking density, group size, nests, provision of litter, perches and platforms, drinkers and feeders, of covered veranda and outdoor range) for an enclosure for keeping broiler chickens (fast-growing, slower-growing and broiler breeders) are recommended. Finally, 'total mortality', 'wounds', 'carcass condemnation' and 'footpad dermatitis' are proposed as indicators for monitoring at slaughter the welfare of broilers on-farm.

Playing in 'The Backyard': Environmental Features and Conditions of a Natural Playspace Which Support Diverse Outdoor Play Activities among Younger Children.

Outdoor play in nature-rich spaces has been associated with healthy development among young children. The diverse play opportunities afforded to children by natural playspaces can scaffold health benefits, appreciation of nature, and pro-environmental behaviors into adulthood. Environmental features and conditions of outdoor playspaces significantly influence the diversity and quality of play opportunities. Understanding how the physical environment can support high-quality play experiences can inform the design of stimulating, health-promoting playscapes for children. An observational behavior mapping framework was utilized to examine the environmental features of The Backyard, a large natural playscape, associated with play activities among young children. The Tool for Observing Play Outdoors was used to capture outdoor play types OPT), along with associated behavioral and environmental data, during seven days of field observation. While the playspace supported most OPTs, Physical and Exploratory play were most prevalent. Associations with activity intensity and risk play are also presented. Loose parts, particularly natural loose parts, were highly involved in most OPTs, but especially associated with Exploratory play. Ground topography showed some association with several OPTs and warrants further investigation. The environmental features of The Backyard supported an abundant and diverse range of outdoor play activities for young children and families.

Welfare issues and potential solutions for laying hens in free range and organic production systems: A review based on literature and interviews.

In free-range and organic production systems, hens can make choices according to their needs and desires, which is in accordance with welfare definitions. Nonetheless, health and behavioral problems are also encountered in these systems. The aim of this article was to identify welfare challenges observed in these production systems in the EU and the most promising solutions to overcome these challenges. It is based on a review of published literature and research projects complemented by interviews with experts. We selected EU specific information for welfare problems, however, the selected literature regarding solutions is global. Free range use may increase the risk of infection by some bacteria, viruses and parasites. Preventive methods include avoiding contamination thanks to biosecurity measures and strengthening animals' natural defenses against these diseases which can be based on nutritional means with new diet components such as insect-derived products, probiotics and prebiotics. Phytotherapy and aromatherapy can be used as preventive and curative medicine and vaccines as alternatives to antibiotics and pesticides. Bone quality in pullets and hens prevents keel deviations and is favored by exercise in the outdoor range. Free range use also lead to higher exposure to variable weather conditions and predators, therefore shadow, fences and guard animals can be used to prevent heat stress and predation respectively. Granting a free range provides opportunities for the expression of many behaviors and yet many hens usually stay close to the house. Providing the birds with trees, shelters or attractive plants can increase range use. Small flock sizes, early experiences of enrichment and personality traits have also been found to enhance range use. Severe feather pecking can occur in free range production systems, although flocks using the outdoor area have better plumage than indoors. While many prevention strategies are facilitated in free range systems, the influence of genetics, prenatal and nutritional factors in free range hens still need to be investigated. This review provides information about practices that have been tested or still need to be explored and this information can be used by stakeholders and researchers to help them evaluate the applicability of these solutions for welfare improvement.

SNeRF

This paper presents a stylized novel view synthesis method. Applying state-of-the-art stylization methods to novel views frame by frame often causes jittering artifacts due to the lack of cross-view consistency. Therefore, this paper investigates 3D scene stylization that provides a strong inductive bias for consistent novel view synthesis. Specifically, we adopt the emerging neural radiance fields (NeRF) as our choice of 3D scene representation for their capability to render high-quality novel views for a variety of scenes. However, as rendering a novel view from a NeRF requires a large number of samples, training a stylized NeRF requires a large amount of GPU memory that goes beyond an off-the-shelf GPU capacity. We introduce a new training method to address this problem by alternating the NeRF and stylization optimization steps. Such a method enables us to make full use of our hardware memory capacity to both generate images at higher resolution and adopt more expressive image style transfer methods. Our experiments show that our method produces stylized NeRFs for a wide range of content, including indoor, outdoor and dynamic scenes, and synthesizes high-quality novel views with cross-view consistency.

Commercial layer hybrids kept under organic conditions: a comparison of range use, welfare, and egg production in two layer strains

Outdoor range areas provide laying hens with improved opportunities to perform natural behaviors and increase the available space per bird, however, birds are also exposed to potentially stressful factors including weather and predators. Ability to cope with challenging environments varies between different strains and must be considered to ensure good welfare. The aim of this study was to determine how suitable 2 hybrids, the Dekalb White (DW) and the Bovans Brown (BB), are for organic production with special emphasis on ranging behavior. A total of 1,200 hens were housed according to organic regulations across 12 flocks of 100 birds. Range and shelter use, effect of weather, vegetation cover, egg production and quality, and mortality were assessed in addition to a range of clinical welfare indicators. Initially a greater proportion of DW hens accessed the range. However, after approximately 2 mo, a greater proportion of BB were using the range and venturing further from the house. DW hens were more likely to use the shelters than BB hens (P < 0.001). Vegetation was also worn away to a greater extent in the BB ranges. Weather affected the proportion of hens that went outside, the distance ranged from the popholes, and shelter use. BB hens were found to have better plumage condition (P < 0.001), fewer footpad lesions (P < 0.001), fewer comb wounds (P < 0.001), and lower mortality rates (P = 0.013). Both hybrids experienced keel bone fractures, though DW hens had more at the cranial portion (P < 0.001) and BB at the caudal portion (P < 0.001). DW hens had an earlier onset of lay and higher egg production than BB hens (P < 0.001), though BB hens laid heavier eggs (P < 0.001) with thicker shells (P = 0.001). Overall, BB hens seemed to perform superiorly or equivalently to the DW hens for all variables apart from egg production. These results demonstrate the importance of considering the strain of bird selected for organic production systems in order for the birds to reap the potential benefits that are offered by outdoor access.

Impacts of Rearing Enrichments on Pullets' and Free-Range Hens' Positive Behaviors across the Flock Cycle.

Simple SummaryEnrichment during the indoor rearing of young laying hens (pullets) destined for free-range systems may improve pullet development and increase motivated natural behaviors (termed ‘positive behaviors’) such as foraging, dust bathing and chick play. Hy-Line Brown® chicks (n = 1700) were floor-reared indoors across 16 weeks with three enrichment treatments (n = 3 pens/treatment): (1) standard control, (2) weekly novel objects—‘novelty’, (3) perching/navigation structures—‘structural’. Pullets (16 weeks old: n = 1386) were then transferred to nine identical pens within rearing treatments, with outdoor range access from 25 to 65 weeks. Video cameras recorded the pullet pens, adult indoor pens, and outside range. During rearing, observations of play behavior in chicks at 2, 4 and 6 weeks showed no overall effect of rearing treatment. At 11 and 14 weeks only the novelty hens were observed to increase their foraging across age with no differences between treatments in dust bathing. Observations of adult hens at 26, 31, 41, 50, 60 and 64 weeks showed that the structural hens exhibited more dust bathing and foraging overall than the control hens, but that both novelty and/or structural hens showed small increases relative to control hens depending on the behavior and location. Across age, adult hens differed in the degree of dust bathing performed inside or outside and foraging outside but not inside. For litter-reared pullets, additional enrichments may result in some long-term increases in positive behaviors. Enrichment during the indoor rearing of pullets destined for free-range systems may optimize pullet development including increasing motivated natural behaviors (termed ‘positive behaviors’) including foraging, dust bathing and chick play. Hy-Line Brown® chicks (n = 1700) were floor-reared indoors across 16 weeks with three enrichment treatments (n = 3 pens/treatment): (1) standard control, (2) weekly novel objects—‘novelty’, (3) perching/navigation structures—‘structural’. At 16 weeks, pullets (n = 1386) were transferred to nine identical pens within rearing treatments with outdoor range access from 25 to 65 weeks. Video cameras recorded the pullet pens, adult indoor pens, and outside range. During rearing, observations of play behavior (running, frolicking, wing-flapping, sparring) in chicks at 2, 4 and 6 weeks (total of 432 thirty-second scans: 16 observations × 3 days × 9 pens) showed no overall effect of rearing treatment (p = 0.16). At 11 and 14 weeks only the ‘novelty’ hens were observed to increase their foraging across age (p = 0.009; dust bathing: p = 0.40) (total of 612 thirty-second scans per behavior: 17 observations × 2 days × 2 age points × 9 pens). Observations of adult hens at 26, 31, 41, 50, 60 and 64 weeks showed that the structural hens exhibited overall more dust bathing and foraging than the control hens (both p < 0.04) but both novelty and/or structural hens showed small increases depending on the behavior and location (total of 4104 scans per behavior: 17 observations × 2 days × 6 age points × 9 pens × 2 locations = 3672 + an additional 432 observations following daylight saving). Across age, adult hens differed in the degree of dust bathing performed inside or outside (both p ≤ 0.001) and foraging outside (p < 0.001) but not inside (p = 0.15). For litter-reared pullets, additional enrichments may result in some long-term increases in positive behaviors.

Conditions for the formation of ice dams on pitched roofs of buildings with cold attics

Introduction. The article describes the mechanism of ice formation on the roofs of buildings with pitched roofs and cold attics.&#x0D; Materials and methods. The authors developed a model and a heat balance equation for an unheated attic room and proposed a set of measures to normalize the temperature and humidity modes in unheated attics.&#x0D; Results. The study demonstrates dependences between the air temperature in the attic and the outdoor air temperature before and after the implementation of the proposed set of measures designated to normalize the temperature and humidity modes. The findings suggest that after the insulation of (1) enclosing structures separating a cold attic from heated rooms, (2) the walls of ventilation ducts, crossing the attic space and (3) the pipelines of the down-feed heating system, the outdoor temperature range is significantly reduced, which reduces the likelihood of roof icing.&#x0D; Conclusions. In addition, the implementation of the proposed set of engineering and technological measures allows not only increasing the thermal insulation of enclosing structures and pipelines of a heating system, but also reduces thermal energy losses in transmission and the consumption of thermal energy in a building during a cold season, improves the indoor climate parameters on the upper floors of a building, reduces the risks of damage to the roofing during mechanical snow removal, thereby increasing the maintenance period of structural and enclosing elements of the roof.

A Fast ISAR Tomography Technique for Fully Polarimetric 3-D Imaging of Man-Made Targets

The 3-D inverse synthetic aperture radar (ISAR) tomography is an enabling technique for applications such as the exact diagnosis of scattering mechanisms for complex targets. Nevertheless, current ISAR tomography solutions still suffer from problems such as the great computational complexity and optimal utilization of the signatures acquired from limited baselines. In this work, we propose a fast ISAR tomography technique for fully polarimetric 3-D imaging of man-made targets. A stack of 2-D complex-valued images with different baselines and polarizations is first obtained through a phase error calibration (PEC) process and graphic processing unit accelerated polarimetric filtered backprojection. A polarimetric state-space decomposition (P-SSD) algorithm is then developed which could provide joint 3-D reconstruction results with low computational complexity. Examples from both numerical multibaseline data for the Sandia laboratories implementation of cylinders (SLICY) benchmark model and the outdoor range dataset collected by the Georgia Tech Research Institute (GTRI) are presented to demonstrate the superior performance and the usefulness of the proposed technique.