Enclosure Size Research Articles

Numerical Study on the Impact of the Richardson Number on Convection in an Enclosure, with Moving Sidewalls for Three Aspect Ratios: A = 1, 2 and 0.5

Using mathematical models, this research investigation seeks to explore how varying aspect ratios and the Richardson number impact the mixing effectiveness, fluid flow velocity, and heat transfer characteristics in a rectangle-shaped space where cooling occurs along the sides and warm with a steady temperature exists throughout the 80% of the bottom section's center. Discretizing the governing equations through the finite volume approach, we solved them iteratively using the Tri-diagonal Matrix Algorithm, where pressure-velocity coupling was successfully implemented via the SIMPLER procedure. Innovative approaches for convection and diffusion terms involved employing a power-law difference scheme alongside a central differential scheme. In various simulations with specified parameters (Re = 100, Pr = 0.71), we visualized results in forms like streamlines, isothermal lines, and temperature/velocity profiles, along with local and average Nusselt numbers. We observe five unique structure formations during flow behavior by analyzing how Richardson numbers impact heat transmission within a specific geometric configuration (enclosure size A = 1). A change in aspect ratio leads to improved control over fluid movement while minimizing structural distortion. A subtle rise in heat transmission emerged as the average Nusselt number and Richardson number intersection strengthened force convection's domination while experiencing significant escalation under conditions conductive to natural convection. Decreasing the aspect ratio increased heat transfer efficiency when the Richardson number rose.

Assessing the Current Landscape of Reptile Pet Ownership in Hong Kong: A Foundation for Improved Animal Welfare and Future Research Directions.

We investigated the evolving landscape of reptile pet ownership in Hong Kong. Employing a quantitative approach, a self-administered survey was distributed and over 200 reptile pet owners residing in Hong Kong responded. The survey instrument captured demographic data on pet ownership history, species preferences, husbandry practices, and veterinary care utilization. The findings revealed a strong interest in pet reptiles, with lizards being particularly popular (67%) among new owners. Turtles remain common (35%), likely due to cultural factors and perceived ease of care. However, a gap was noted between the awareness and the implementation of proper husbandry practices, with 51% of respondents expressing concerns about enrichment and 21% uncertain about appropriate enclosure size. Veterinary care utilization also showed a disconnect, with 50% of the respondents reporting no regular check-ups were performed, despite acknowledging its importance. Reptile behavior served as a well-being indicator. Over 90% of the respondents observed normal behaviors like locomotion and breathing. Interestingly, a positive correlation emerged between reptile behavior scores and duration of ownership (r = 0.200, p < 0.01), suggesting improved well-being for reptiles that were in long-term care. These findings emphasize the need for educational initiatives promoting responsible pet ownership practices and fostering collaboration between reptile owners, veterinarians, and animal welfare organizations. By addressing these knowledge gaps and promoting a collaborative approach, our results aim to contribute to enhanced reptile welfare in the context of Hong Kong's evolving pet ownership trends.

Welfare Implications for Tigers in Travelling Circuses.

There are very few studies that have focused on species-specific welfare implications for tigers in a travelling circus. The absence of scientific evidence to inform nationwide legislation means that tigers are still commonly used in travelling circuses across the world. A systematic review of relevant published studies was conducted using the bibliographic databases Web of Science and Scopus, supplemented by a narrative search. In total, 42 relevant studies were identified that assessed the welfare of tigers in captivity, including circuses and zoos. Only eight papers assessed the welfare implications for tigers in circuses directly, evidencing the lack of research in this area. Given that circuses provide a sub-optimal environment compared to zoos, implications for tiger welfare were also inferred from zoo research, within the Five Domains framework. Collectively, these papers infer that the travelling nature of a circus often negatively impacts the welfare domains of nutrition, physical environment, health, and mental state. This is due to limitations in enclosure size, as well as in both environmental and behavioural enrichment. There is also often difficulty in sourcing appropriate food and specialised routine veterinary care. The literature is divided concerning behavioural interactions, specifically whether training can improve welfare by offering mental stimulation. However, circus performances are often associated with negative welfare due to noise disruption from spectators. The collective scientific evidence indicates that tigers are not well suited to circus living, due to the inability of a travelling circus to provide for their species-specific psychological, physiological, and behavioural needs.

STUDY OF DIAGNOSIS, ASSOCIATED RISK FACTORS AND IN-VITRO ANTIBIOTIC SUSCEPTIBILITY OFSALMONELLA ISOLATED FROM OSTRICH (STRUTHIO CAMELUS)

The ostrich meat is considered healthy as it contains low cholesterol and fat levels. Foodborne diseases caused by the bacterium Salmonellaare a significant public health concern. The study was conducted to determine the prevalence, the risk factors involved, and antimicrobial susceptibility patterns of Salmonella isolates recovered from captive ostrich feces in the district of Lahore, Pakistan. There is not a single research on this issue in Pakistan up to date in ostrich. A total of 100 ostrich fecal samples were collected- and specifically cultured on Salmonella Shigella agar. The antimicrobial susceptibility was checked for different antibiotics throughthe Kirby-Bauer disc diffusion method. The 21% fecal samples were found positive for Salmonella. The disease was found to besignificantly(p&lt;0.05) associated with risk factors; water type(p=0.027), bird’s capacity(p=0.042), cage hygiene(p=0.024), age of bird(p=0.041) andother bird species around (p=0.031) while enclosure size and diet were found non-significant. The bacterium was found highly susceptible to Amoxicillin followed by Chloramphenicol, Gentamicin, Cefotaxime, andEnrofloxacin respectively.Further Salmonella species-level diagnostic studies along with susceptibility checks of more therapeutic agents are suggested to future researchers.

A Comparative Multi-Zoo Survey Investigating the Housing and Husbandry of Callimico goeldii

Callimico (Callimico goeldii) are members of the callitrichid family, and a species of conservation concern managed within the European Association of Zoos and Aquaria (EAZA) ex situ program. They benefit from extensive ‘Best Practice’ guidelines developed by the Callitrichid Taxon Advisory Group (TAG), but there are gaps in species-specific knowledge and captive management research. A survey was created to understand and evaluate current housing and husbandry within EAZA collections holding callimico. The questionnaire allowed collation of details including enclosure size along with prevalence of mixed species exhibits, use of UV-B lighting, enclosure complexity and enrichment routines. Responding collections represented 44% of the current callimico holders, with the results allowing comparative analysis of current practice against the guidelines and considering previous research. Significant positive differences were discovered between minimum recommended enclosure dimensions, including total enclosure volume, 32 m3 (p &lt; 0.001, median = 100) and height, 2.5 m (p &lt; 0.001, median = 3) versus EAZA’s minimum recommended dimensions. Encouragingly, no significant difference in complexity was found between on and off exhibit housing, but the results suggest that being housed in a mixed species exhibit offers a more complex environment for callimico (W = 405.5, p &lt; 0.005). The responses revealed overall good practice, although a disparity was noted in the provision of UV-B lighting and the prevalence of enrichment. Observational research focusing on spatial use, preference and behavior is recommended to complement husbandry guidelines. Reference of the survey findings to welfare indicators could determine the effect of current housing and husbandry on callimico welfare.

Kibble diet is associated with higher faecal glucocorticoid metabolite concentrations in zoo-managed red wolves (Canis rufus).

The red wolf (Canis rufus) is a critically endangered canid that exists solely because of the establishment of the ex situ population in the late 1980s. Yet, the population under human care suffers from gastrointestinal (GI) disease in captivity. While the cause of GI disease is unknown, it is speculated that environmental factors can influence GI health of zoo-managed red wolves. The goal of the present study was to investigate the relationship between faecal glucocorticoid metabolite (FGM) concentrations, a biomarker for stress, and environmental factors for zoo-managed red wolves. Faecal samples were collected from 14 adult wolves three times a week for 5 to 12months. Using a single-antibody cortisol enzyme immunoassay, FGM concentrations were quantified. Environmental factors were collected for each participating wolf on dietary type, sex, type of public access to enclosure, density (enclosure size [ft2]/number of wolves living in enclosure) and a monthly average status of GI health. Red wolves that ate a commercial kibble diet had both higher FGM concentrations over time and higher baseline FGM concentrations compared to individuals that received commercial kibble mixed with commercial meat. Density, public access or GI health were not related to FGM concentration; however, males had higher baseline FGM concentrations compared to female red wolves. Our findings suggest that management conditions, particularly diet, can strongly influence FGM concentration in the zoo-managed red wolf population. Findings from this study highlight the importance of management choices on individual welfare. Maintaining a healthy captive population of red wolves is imperative for the persistence of the species, including successful future reintroductions.

Giardia nosode 30cH in the treatment of howler monkey (Alouatta guariba) with giardiasis in captivity in Brazil

The red howler monkey (Alouatta guariba) is an endemic primate of the Atlantic Forest, classified as vulnerable. They're susceptible to giardiasis, impacting human health and Alouatta genus conservation. Studies report parasite occurrence in wild and captive individuals. While asymptomatic infections are common in captivity, immunosuppression can lead to severe cases. São Paulo's Wildlife Division maintains a large captive population. To assess Giardia duodenalis presence, fecal samples were collected from 43 individuals in 17 enclosures over three days, totaling 153 examinations. Animals were asymptomatic, with some groups showing loose stools. Two processing methods (direct and Sheather) were used, followed by quantitative evaluation based on cysts per slide. Only one enclosure tested negative; others were rare (4), slight (8), or moderate (4). Despite being asymptomatic, treatment was chosen to prevent positive animals from spreading infection. Allopathic treatment was impractical due to enclosure size; homeopathic Giardia 30cH nosode was given via water and food for 15 days to 16 positive enclosures. Afterward, 144 fecal samples were reanalyzed over three days. Seven enclosures were negative, 8 were rare, one was slight, none were moderate. All had firm feces. Kruskal-Wallis test confirmed significant treatment (p=0.004). Giardia 30cH nosode reduced parasitism, environmental contamination, with easy administration and no stress/adverse effects.

Upper airway morphology in adults with positional obstructive sleep apnea

PurposeTo compare the anatomical balance and shape of the upper airway in the supine position between adults with positional obstructive sleep apnea (POSA) and adults with non-positional OSA (NPOSA).MethodsAdults diagnosed with OSA (apnea-hypopnea index (AHI) > 10 events/h) were assessed for eligibility. POSA was defined as the supine AHI more than twice the AHI in non-supine positions; otherwise, patients were classified as NPOSA. Cone beam computed tomography (CBCT) imaging was performed for every participant while awake in the supine position. The anatomical balance was calculated as the ratio of the tongue size to the maxillomandibular enclosure size. The upper airway shape was calculated as the ratio of the anteroposterior dimension to the lateral dimension at the location of the minimal cross-sectional area of the upper airway (CSAmin-shape).ResultsOf 47 participants (28 males, median age [interquartile range] 56 [46 to 63] years, median AHI 27.8 [15.0 to 33.8]), 34 participants were classified as having POSA (72%). The POSA group tended to have a higher proportion of males and a lower AHI than the NPOSA group (P = 0.07 and 0.07, respectively). After controlling for both sex and AHI, the anatomical balance and CSAmin-shape were not significantly different between both groups (P = 0.18 and 0.73, respectively).ConclusionAdults with POSA and adults with NPOSA have similar anatomical balance and shape of their upper airway in the supine position.Trial registrationThis study was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR Trial ACTRN12611000409976).

Factors affecting captive female giraffe stress response: Male presence, small enclosure, and low temperature.

To improve animal welfare based on suitable social housing conditions, it is important to understand the factors that trigger high-stress responses. Wild giraffes live in a fission-fusion society and males and females are rarely in the same herd for a long period. The captive condition of belonging to a herd with the same individuals for months or years is uncommon in nature. To understand the effect of male presence on female stress levels, fecal glucocorticoid metabolite (fGCM) levels and social interactions in two captive female giraffes were investigated. Additionally, the effect of enclosure size and temperature on fGCM level and social interactions were examined. The results showed no significant difference in the fGCM levels of females based on male presence. The frequency of agonistic behavior by the dominant female toward the subordinate female was significantly increased when a male was present. The subordinate female was significantly less likely to approach the dominant female and showed decreased affiliative and agonistic interactions toward the dominant female when a male was present. The frequencies of agonistic interactions between females were higher in the small enclosure regardless of male presence. Low temperature triggered higher fGCM levels and increased agonistic interaction in an aged female. The findings of this study suggest that these multiple factors should be considered individually to promote the welfare of captive giraffes.

The effect of visitors on the behaviour of zoo-housed primates: A test of four hypotheses

The effects of human visitors on the behaviour and welfare of zoo-housed primates have been extensively studied, and we know more about these effects in primates than in any other taxon. Nevertheless, it has proved difficult to detect an overall pattern in the responses of primates to visitors, as the presence of people can be stressful to the animals, but in some circumstances can be enriching, and in other circumstances the animals appear to be largely unaffected. Several potential causal factors have been suggested, namely that variability is due to species-specific differences, differences in visitor characteristics and behaviour, differences in housing and husbandry, or differences in individual characteristics of the animals, and these can be treated as four hypotheses to account for this variability in response. Here we test these four hypotheses using published data. A significant association was found between animal response and ecological category, such that small arboreal primates were most likely to be affected negatively. Visitor characteristics showed a significant association with animal response with noisy visitors having the most stressful effect. There was no significant effect of enclosure size or group size, though there was a significant association with enclosure type, such that animals in walk-through and semi-free range enclosures were more likely to show positive responses, though the small number of examples of these suggests treating this result with caution. Finally, individual differences were tested with gorillas, where there were sufficient data to look at individuals rather than animal groups. There was no significant effect of age or sex, but regression using all of the potential causal variables produced a significant model in which no individual predictor was significant, suggesting that it is the combination of predictors which influences the form of the response.

Effects of different cage sizes and nest settings on laying hen nesting behavior and the proportion of dirty eggs in furnished cages

Furnished cages may promote laying hen welfare more than the traditional cage, but the high proportion of dirty eggs in the furnished cage system could directly affect the exterior quality of eggs, reducing the economic advantage of the furnished cage production system. The problem of the high proportion of dirty eggs reveals defects in the design of the cage, and it may also indicate competition among hens, affecting the utilization of nests. The research aimed to examine the effects of cage size, nest location, and degree of enclosure on behavioral adaptation and the proportion of dirty eggs. Nine hundred laying hens (Hy-line Brown) were housed in cages with eight different types of nests, and the experiment began at the 18 weeks of age and ended at week 38. The proportion of dirty eggs and the nesting behavior of hens were recorded. The number of nest visits and the sitting behavior of the hens in the medium furnished cage were significantly higher than in the large furnished cage (visits: P < 0.01; sitting: P < 0.01). The number of nest visits in the higher nests was significantly greater to lower nests (P = 0.01). The number of nest visits in the enclosed type nests was significantly higher than in the open type nests (P = 0.01). The cage size, nest location, and amount of enclosure had no significant effect on the proportion of dirty eggs (P > 0.05). In conclusion, the enclosed nests in a higher location were more attractive for laying hens.

Feeding, mating and animal wellbeing: new insights from phylogenetic comparative methods.

Feeding, mating and animal wellbeing: new insights from phylogenetic comparative methods.

Thermal evaluation of junction and connection boxes in explosion protection

To reliably avoid potential ignition sources and thus ignition of the potentially explosive atmosphere in junction and connection boxes of type of protection Increased Safety ‘e', the self-heating shall not exceed a specified level depending on the temperature class. For the conformity assessment of such products, complex thermal tests are necessary due to the great variety of mounting types and arrangements of terminal blocks in the enclosure, depending on the enclosure size. These tests are very time-consuming for the manufacturer of junction and connection boxes or for the testing laboratory and are therefore associated with considerable costs. To reduce this effort and to ensure a uniform assessment in the conformity evaluation by a certification body, it is therefore essential to create fitting charts depending on the enclosure size.This work introduces a calculation tool by means of systematic investigations on different enclosure sizes and with different assemblies, which enables the calculation of fitting charts with justifiable effort. For this purpose, the maximum temperature in the enclosure was determined as a function of the current and the assembly at 20 ± 5 °C ambient temperature. From this, electrical and enclosure-specific constants such as the maximum permissible current per conductor and a conductor specific factor were determined and combined with an exponential dependence of the power dissipation. It is shown that this relationship is valid for an overtemperature of 40 K for compliance with temperature class T6 up to an ambient temperature of +40 °C. Finally, to verify the reliability of the calculation tool, the results are compared with the enclosure-specific rated value of the maximum power dissipation according to IEC 60079-7, 5.7.

Behavioural Impact of Captive Management Changes in Three Species of Testudinidae

Reptile behaviour and welfare are understudied in comparison with mammals. In this study, behavioural data on three species (Astrochelys radiata, Stigmochelys pardalis, Aldabrachelys gigantea) of tortoises were recorded before and after an environmental change which was anticipated to be positive in nature. The environmental changes differed for each population, but included a substantial increase in enclosure size, the addition of substrate material, and a change in handling procedure. A tortoise-specific ethogram was created to standardise data collection. Focal behaviour sampling was used to collect behavioural data. Changes in the duration of performance of co-occupant interaction and object interaction in the leopard (Stigmochelys pardalis) and Aldabra (Aldabrachelys gigantea) tortoises were observed following the environmental changes. The Shannon–Weiner diversity index did not yield a significant increase after the changes but had a numerical increase which was relatively greater for the leopard tortoise group, which had experienced the greatest environmental change. The leopard tortoises also demonstrated changes in a greater number of behaviours compared to the other species, and this was sustained over the study period. However, this included a behaviour indicative of negative affect: aggression. Whilst we are unable to conclude that welfare was improved by the management changes, there are suggestions that behavioural diversity increased, and some promotion of positive social behaviours occurred.

Pet management practices of frog and turtle owners in Victoria, Australia.

Available empirical evidence suggests that pet animals do not always experience an optimal welfare state. However, most pet welfare research has focused on dogs and cats, with less research investigating amphibians and reptiles. The aim of this study was to characterise how owners of pet frogs and turtles in Victoria, Australia, attempted to meet their pets' welfare needs. Pet frog owners (n= 128) and turtle owners (n= 60) completed an online survey, comprising questions about how they managed their pets' environmental, behavioural, social, nutritional and physical health needs. For both frogs and turtles, positive and negative welfare indicators were found. Owners described pet enclosures as waterproof and escape-proof. However, fewer than 20% of owners of either pet type had an enclosure size that met the minimum standards described in the relevant Code of Practice. Because this study relied on self-reporting, future research should directly observe animals under household care to provide a more objective measure of welfare. Pet frogs and turtles in Victoria, Australia, may not always be experiencing an optimal welfare state, despite their owners' stated desire to care for them as well as possible.

Monitoring of Cortisol Levels in Hog Deer with Varying Environment Exposure

Hog deer (Axis porcinus) is one of the least studied animal species in Pakistan. It belongs to Order Artiodactyla and the family Cervidae. IUCN classified Axis porcinus as an endangered species in 2008. The present study was conducted to investigate the effects of varying environmental exposure, genders, and seasonal changes on captive hog deer (A. porcinus) at Lahore Zoo, Safari Zoo, and Jallo Park in Lahore, Pakistan. Non-invasive techniques were used to monitor stress levels in hog deer. For sample collection, four definite months belonging to two seasons’ winter and summer were considered. A total of 48 urine and faecal samples were collected from both male and female hog deer. Seasonal fluctuations have been found to have a significant impact on faecal and urinary cortisol levels. Higher cortisol levels were found in both male and female hog deer in the summer season at all three visited sites. Fluctuations in environmental exposure at three research sites had a significant impact on faecal and urinary cortisol levels. Higher levels of cortisol were found in both male and female hog deer at Jallo park and Lahore Zoo, as compared to Safari Zoo. It was concluded that lower cortisol levels at Safari Zoo might be due to better environmental conditions and more flexible enclosure size and interaction of various species of deer. Temperature affected hog deer cortisol levels in summer, as higher levels were measured in summer compared to winter. In addition, sex did not predict any stress levels in hog deer. It has been suggested that a large enclosure size can control levels of cortisol in hog deer.

Transient risk of water layer formation on PCBAs in different climates: Climate data analysis and experimental study

The reliability of electronic devices depends on the environmental loads at which they are exposed. Climatic conditions vary greatly from one geographical location to another (from hot and humid to cold and dry areas), and the temperature and humidity vary from season to season and from day to day. High levels of temperature and relative humidity mean high water content in the air, but saturated conditions (i.e. 100 % RH) can also be reached at low temperatures. This paper analyses the relationship between temperature, dew point temperature, their difference (here called ΔT), and occurrence and time period of dew point closeness to temperature on transient condensation effects on electronics.This paper has two parts: (i) Data analysis of typical climate profiles within the different zones of the Köppen -Geiger classification to pick up conditions where ΔT is very low (for example ≤0.4 °C). Various summary statistics of these events are calculated in order to assess the temperature at which these events happen, their durations and their frequency and (ii) Empirical investigation of the effect of ΔT ≤ 0.4 °C on the reliability of electronics by mimicking an electronic device, for which the time period of the ΔT is varied in one set of experiments, and the ambient temperature is varied in the other. The effect of the packaging of the electronics is also studied in this section.The statistical study of the climate profiles shows that the transient events (ΔT ≤ 0.4 °C) occur in almost every location, at different temperature levels, with a duration of at least one observation (where observations were hourly in the database). The experimental results show that presence of the enclosure, cleanliness and bigger pitch size reduce the levels of leakage current, while similar high levels of leakage current are observed for the different durations of the transient events, indicating that these climatic transient conditions can have a big impact on the electronics reliability.

A survey exploring the impact of housing and husbandry on pet snake welfare

AbstractSnake ownership is popular; however, housing and care may not always satisfy the animal's welfare needs. For example, snakes are often kept in environmental conditions that restrict their ability to stretch out fully or move around, using rectilinear locomotion. To date, little empirical data exist on the housing and husbandry of captive snakes and how these impact welfare. This study analyses survey responses from 744 snake owners worldwide and explores potential welfare concerns for snakes kept within private homes. It documents the most common housing and husbandry methods and compares the three most common families (Pythonids, Boids and Colubrids). Owner-reported data were used to derive scores for two potential welfare indicators: number of clinical signs of ill health and the number of reported negative (abnormal) behaviours. Using these indicators, associations were tested with snake-keeping variables, such as enclosure size, level of enrichment, temperature and humidity. Owners reported that 90.7% (n = 675) of snakes adopted rectilinear (straight-line or near straight-line) positions or movements. Snakes kept in enclosures &gt; 1 snake length tended to have more enrichment types and were reported with fewer clinical signs of ill health. Some snakes were housed at unknown temperature (7.7%) or humidity (48.1%) ranges or in environmental conditions not in keeping with current recommended guidelines. Corn snakes (Pantherophis guttatus) were the most likely species to be kept at a humidity which did not match recommendations which may present a welfare concern. This study's results can be used to target husbandry guidance for future recommendations and care manuals.

Effects of Group Sizing on Behavior, Welfare, and Productivity of Poultry

The excessive intensive production of poultry meat and egg caused significant changes in poultry husbandry, behavior, and welfare. Therefore, animal welfare and behavior have become an important issue in poultry production and arises the necessity to reconsider all husbandry practices including group size and density. This review aims to investigate the association of group size with growth performance, detrimental behaviors, and welfare by reviewing current norms and regulations, as well as scientific literature in industrial poultry farms, including chicken, turkey, and quail. It has been found that group size can affect production performance, especially growth rates, feed efficiency, and number of competitors, which can lead to damaging behavior and consequently injuries in poultry. Due to the intensification of the poultry production systems, many natural behaviors of domesticated poultry, including food search strategies, hierarchy formation, and aggressiveness, are changed or modified, compared to their ancestors. Therefore, challenging behaviors in commercialized conditions and large groups of poultry must be investigated. The current recommendations and regulations of the industry for commercial poultry on group size and space requirements differ from scientifically investigated trials. On the other hand, available scientific research about the impact of flock size on poultry welfare, behavior, and production, has been carried out in experimental settings with flock sizes that are varied considerably from those used in the commercial settings. In conclusion, results from studies on optimum group size have indicated some degree of confounding and interactions between enclosure size and density. Furthermore, the social and physical environment can have a significant impact on a variety of welfare-related aspects and behavioral indicators. It is important to note that this evaluation focused on studies conducted in experimental settings, making it difficult to extrapolate the findings to commercial settings where thousands of birds are reared at once.

Prevalence Patterns for Enteric Parasites of Chickens Managed in Open Environments of the Western United States.

Growing demand for poultry meat and eggs labeled as organic, cage free, or pasture raised has increased the number of producers that manage chickens outdoors. In these open environments, there are likely diverse enteric parasites sustained by fecal-oral transmission or passage through intermediate invertebrate hosts (e.g., worms and insects) that chickens consume. Enteric parasites can reduce chicken health and productivity, but there are few published data describing the identities or prevalence of these parasites on farms that use open environments in the United States. We surveyed 27 poultry farms with open environments that were situated across a wide geographic range, including California, Oregon, Idaho, and Washington. These farms did not use anticoccidial drugs, coccidia vaccines, or parasiticides. Flock size, enclosure area, flock density, flock rotation frequency, and average flock age were highly correlated for all the farms in this study. We analyzed how enclosure size and flock rotations per year (which represented two axes of variation in management) correlated with prevalence of five observed parasite taxa at the farm level. Across all flocks, we detected by fecal flotation Eimeria spp. (95% flocks), Ascaridia galli (69%), Heterakis gallinarum (52%), Capillaria spp. (39%), Strongyloides avium (13%), tapeworm species (29%), Cryptosporidium spp. (3%), and Dispharynx nasuta (1%). Eighty-five percent of samples were coinfected with two or more parasite taxa. Sixty-seven percent of farms raised only layer chicken breeds, 4% raised only broiler breeds, and 30% raised both layer and broiler breeds. The average age of the broiler flocks was 11.0 wk (±1.1 SE), and flocks were moved 54.7 (±17.9) times annually to new locations in pastures (hereafter, "rotation"). Layer flocks averaged 84.9 (±7.67) wk of age and were moved less often on farms being rotated 20.0 (±6.05) times per year. Generalized linear mixed models indicated that for every 1 m2 increase in enclosure size, the odds of detecting Eimeria spp. increased by 0.03%. Furthermore, for every additional rotation per year, the odds of detecting A. galli decreased by 1.3%. For every additional rotation per year, the odds of detecting tapeworm species increased by 2.2%. We found no evidence that flock spatial management affected prevalence of the other parasites observed on the farms. Farming practices and parasite responses in these systems are highly varied, which makes it difficult to identify potential management interventions for reducing these infections.