Large Enclosure Research Articles

Antipredator Responses by Texas Horned Lizards to Two Snake Taxa with Different Foraging and Subjugation Strategies

The discrimination ability of Texas Horned Lizards (Phrynosoma cornutum) during antipredator responses was tested with snakes of two genera having distinctly different prey foraging and subjugation strategies; Western Diamondback Rattlesnakes (Crotalus atrox) are “sit-and-wait” predators with a venomous strike from ambush, whereas whipsnakes (Masticophis spp.) are nonvenomous, rapid pursuit-and-grasp predators. Neither snake constricts prey; both ingest prey whole. Lizards were watched for reactions during close approaches by moving snakes. All unapproached and some approached lizards remained alert and motionless. Approached lizards that reacted either (1) ran rapidly to a distant point in the large enclosure, or (2) maintained their position but dorsoventrally flattened their body and tilted their stance, orienting a “dorsal shield” posture toward the snake. The distinctly contrasting responses of the lizards to the two snakes were significantly different, relocation running from rattlesnakes and stationary-body reorientation toward whipsnakes. For slow-running, broad-bodied Texas Horned Lizards, running is an appropriate escape response to a nonpursuing venomous predator, whereas the nonrunning body-conformation/orientation change is an appropriate defensive response, advertising size and spiny defenses, to a rapid-pursuit snake that must grasp prey with its jaws to effect capture and subjugation. Apparently horned lizards visually recognized, probably innately, the two snake taxa as different categories of predator threat.

Therapeutic effects of complex rearing or bFGF after perinatal frontal lesions

We investigated the effects of an enriched environment and/or basic fibroblast growth factor (bFGF) on recovery from neonatal frontal injury in rats. Rats received medial frontal lesions, or sham surgery, on postnatal day (P) 2/3. In the first set of experiments (Experiments 1 and 2), rats were housed in enriched environments that consisted of a large enclosure with multiple objects (or standard housing) for 90 days beginning at weaning (P22) or in adulthood (P110). In Experiment 3, the rats either received 7 days of subcutaneous bFGF beginning on the day after surgery or bFGF plus enriched housing beginning at weaning. After the 90-day housing period, the animals were tested on a spatial navigation task and a skilled reaching task. Early lesions of the medial frontal cortex caused severe impairments in spatial learning but this deficit was markedly reduced with enriched housing, bFGF, or a combination of both, with the latter being most effective. The housing effects varied with age, however: the earlier the experience began, the better the outcome. Enriched housing increased dendritic length in cortical pyramidal neurons, an effect that was greater in the lesion than the control animals, and enriched housing reversed the lesion-induced decrease in spine density. Enriched environment increased the thickness of the cortical mantle in both lesion and controls whereas bFGF had no effect. Experience thus can affect functional and anatomical outcome after early brain injury but the effects vary with age at experience and may be facilitated by treatment with bFGF.

Relations between open-field, elevated plus-maze, and emergence tests as displayed by C57/BL6J and BALB/c mice

The relations between open-field, elevated plus-maze, and emergence tests were examined in two strains of mice. In the open-field, C57BL/6J mice had more ambulatory movements and rears but not stereotyped movements relative to BALB/c. In addition, C57BL/6J mice entered more often than BALB/c into enclosed and open arms of the elevated plus-maze. When placed inside a large enclosure, C57BL/6J mice emerged more quickly than BALB/c from a small toy object. In the entire series of mice, ambulation and rears in the open-field were linearly correlated with open and enclosed arm visits in the elevated plus-maze. Ambulatory movements and rears were also correlated with emergence latencies. In contrast, stereotyped movements were correlated with emergence latencies, but not with any elevated plus-maze value. These results specify the extent and limits of association between the three tests.

Jet impingement heat transfer on a flat plate at a constant wall temperature

Gas-to-wall heat transfer configuration for a round air jet impinging on a circular flat plate is investigated experimentally to derive an average Nusselt number correlation. The impingement plate is placed at the bottom of a large adiabatic enclosure, and its temperature is imposed, by external circulation of a coolant. The simultaneous measurements of mass flow rate and characteristic temperatures (hot jet, cold wall, enclosure outlet) permit the determination of the average wall heat transfer coefficient, through an enthalpic balance of the enclosure. The jet Reynolds number, nozzle diameter D and nozzle-to-plate distance H are varied. These experimental measurements are compared with the results of a numerical CFD modelling. Simulations under constant wall heat flux conditions are compared to local Nusselt number distributions as given by the current literature, which validates the use of the Shear Stress Transport (SST) k – ω turbulence model for this problem. Simulated Nusselt numbers obtained at a constant wall temperature are found lower than under uniform heat flux conditions. Measurements and simulation results, at a constant wall temperature, are in good agreement. An average Nusselt number correlation is proposed for jet impingement heat transfer calculations under constant wall temperature conditions, as a function of the jet Reynolds number Re j ( 10 000 ⩽ Re j ⩽ 30 000 ) , the geometrical parameters R / D , H / D ( 3 ⩽ R / D ⩽ 10 ; 2 ⩽ H / D ⩽ 6 ), and the dimensionless viscosity ratio μ j / μ w ( 1.1 ⩽ μ j / μ w ⩽ 1.4 ) .

Experimental and Numerical Study of Methane-air Deflagrations in a Vented Enclosure

Results of a series of tests on the deflagration of methane-air mixtures in a large vented enclosure are presented. Experiments were made in FM Global’s 63.7 m3 chamber. The chamber was 4.6 x 4.6 x 3.0 m with a vent opening on one side. Vent areas of either 2.7 or 5.4 m2 were used. Tests were performed with ignition either at the center of the chamber or at the center of the wall opposite the vent. Methane-air mixtures with methane concentrations close to 9.5% vol. were used in the tests. Pressure data, as function of time, and flame time-of-arrival data were obtained both inside and outside the chamber near the vent. Detailed experimental data is used in the paper to test a three-dimensional gasdynamic model for the simulation of gaseous combustion in vented enclosures. The model is based on a Large Eddy Simulation (LES) solver created using the OpenFOAM CFD toolbox using sub-grid turbulence and flame wrinkling models. Results from the calculations are compared with the experimental data. The capabilities and deficiencies of the model are discussed.

Heat, Mass and Aerosol Transfers in Spray Conditions for Containment Application

TOSQAN is an experimental program undertaken by the Institut de Radioprotection et de Surete Nucleaire (IRSN) in order to perform thermal hydraulic containment studies. The TOSQAN facility is a large enclosure devoted to simulating typical accidental thermal hydraulic flow conditions in nuclear Pressurized Water Reactor (PWR) containment. The TOSQAN facility, which is highly instrumented with non-intrusive optical diagnostics, is particularly adapted to nuclear safety CFD code validation. The present work is devoted to studying the interaction of a water spray injection used as a mitigation means in order to reduce the gas pressure and temperature in the containment, to produce gases mixing and washout of fission products. In order to have a better understanding of heat and mass transfers between spray droplets and the gas mixture, and to analyze mixing effects due to spray activation, we performed detailed characterization of the two-phase flow.

Evaluation of a Zonal Model for Large Enclosures Using Computational Fluid Dynamics

A temperature–based zonal model for large enclosures with combined stratification cooling and natural ventilation, proposed in a previous paper by Gao et al, is evaluated using the CFD (Computational Fluid Dynamics) method in this study. The CFD method adopted in this study using the RNG k–ε model with a differential viscosity is able to represent the non–isotropic thermally stratified flows encountered in the large enclosures. It is used to determine a key parameter, the heat transfer factor between adjacent zones in the zonal model due to temperature difference and turbulent penetration, and also to verify the zonal model for the prediction of thermal stratification in large enclosures. In order to avoid the poor representation of surface heat transfer by empirical/semi–empirical expressions suggested for conventional room enclosures, this study feeds a CFD–based coefficient to the zonal model. This treatment also gains an advantage over the experimental method, which is proved to fail in keeping the similarities of thermal buoyancy and surface convection based on the scale modeling. Furthermore, it responds to the influence of detailed information of local flows on the coefficient. Finally, comparison between the zonal model and CFD is carried out for the enclosure conditioned with the combined stratification cooling and natural ventilation, or single stratification cooling. It is found that the results calculated by the zonal model agree considerably well with those by the CFD.

Evidence of effects of human disturbance on alert response in Père David's deer (Elaphurus davidianus)

To understand effects of human disturbance on alert response of Père David's deer, we carried out an experiment in the Dafeng Père David's Deer Reserve (32 degrees 59'-33 degrees 03'N, 120 degrees 47'-120 degrees 53'E), China. In the spring and summer, we observed alert responses (including stare, walking away, and flee) of deer and recorded the intensity of tourist disturbance in a small display pen using a laser-range finder to measure the alert distance of a free-ranging group in a large enclosure. We also recorded the pattern of head orientation when deer were resting in these two deer groups. After statistical analysis, we found that: 1) in small pen, the frequency of alert response was significantly different among different intensities of human disturbance; strong disturbance resulted in higher frequency of alert response; 2) stare distance in the free-ranging group in summer was significantly longer than that in spring, but the distance of walking away and the distance of flee showed no significant difference between the two seasons; and 3) in free-ranging group, there was no significant directional difference in head orientation, whereas in display group, there was a significant directional difference in head orientation. We suggest that: 1) under the captive situation, human disturbance may be one of the factors that affect alert response in Père David's deer; and 2) Père David's deer adopted different alert response to adapt to human disturbance under different circumstance. We recommended that relationships between alert response and human disturbance should be considered in ex situ conservation of this field extinct deer. Zoo Biol 26:461-470, 2007. (c) 2007 Wiley-Liss, Inc.

Calculation of Natural Ventilation in Large Enclosures

There is a need for a good analytical model of natural ventilation of large enclosures. This study describes a multi-layer pattern of thermal stratification in high and large spaces driven by natural ventilation. The pattern is then used to construct an analytical model for natural ventilation of large enclosures. A thermal plume developed in the multi-layer environment is investigated based on its development across each density interface. This kind of plume and the airflows along vertical wall surfaces are combined to establish the heat and mass balances in each thermally stratified layer. Two different mathematical models that model the airflows along vertical wall surfaces are presented. These two models are compared for their predictions of the ventilation flow rate and vertical temperature profiles. Results of both present models are also compared with those calculated by computational fluid dynamics (CFD). It is shown from the comparisons that both models predict reasonably the thermal stratification in the large enclosure but only the one that considers continuous airflow along the whole wallsurface gives reliable predictions which agree well with results from the CFD study.

Rabbits—An Introduction

This issue of the Journal of Exotic Pet Medicine is devoted to rabbits: a reflection of their importance in veterinary practice. Rabbits can make excellent family pets, and the last two decades has seen a significant change in the petowning public’s attitude towards them. Although many rabbits are still kept in solitary confinement in small hutches or cages, an increase in owner awareness has meant that larger numbers are now housed with companions and given the freedom to run/hop in a large enclosure or even the house. No longer are rabbits only considered pets for children. Many adults now choose to own a rabbit rather than a dog or cat. These owners expect a high standard of veterinary care for their pet rabbit. Hopefully, this issue of JEPM can help to achieve that standard. The invitation to edit this issue has given me the opportunity to select some important topics in rabbit medicine and surgery. Dental disease is a major health problem and was the subject of my Fellowship thesis. The findings of this thesis have been condensed into an article describing the progressive changes that take place in the teeth and skulls of rabbits affected by the progressive syndrome of acquired dental disease that is so common in rabbits kept as pets. The increasing popularity of rabbits as pets is a worldwide phenomenon and much valuable information can be found in journals that are written in languages other than English. I first encountered Frank Wagner’s work in 1998 in a German journal and was so impressed by his images that I had to find someone to translate the text. At that time Frank was working at the university at Hannover. He has since moved to Utrecht, where I finally tracked him down, and I was delighted when he agreed to contribute to this issue of JEPM and share his methodical approach to rabbit ophthalmology. Collecting blood and urine samples from rabbits are routine procedures in many veterinary practices, yet interpretation of the results can be difficult. A fasting sample is not possible because of caecotro-

With a Little Help from a Friend

An old female, named Peony, spends her days with other chimpanzees in a large outdoor enclosure near Atlanta, Georgia (United States). On bad days, when her arthritis is acting up, she has great trouble walking and climbing. But other females help her out. For example, Peony is huffing and puffing to get up into the climbing frame in which several chimpanzees have gathered for a grooming session. An unrelated younger female moves behind her, places both hands on her ample behind, and pushes her up with quite a bit of effort, until Peony joins the rest.

Mating success of resident versus non-resident males in a territorial butterfly

Male–male competition over territorial ownership suggests that winning is associated with considerable benefits. In the speckled wood butterfly, Pararge aegeria, males fight over sunspot territories on the forest floor; winners gain sole residency of a sunspot, whereas losers patrol the forest in search of females. It is currently not known whether residents experience greater mating success than non-residents, or whether mating success is contingent on environmental conditions. Here we performed an experiment in which virgin females of P. aegeria were allowed to choose between a resident and a non-resident male in a large enclosure containing one territorial sunspot. Resident males achieved approximately twice as many matings as non-residents, primarily because matings were most often preceded by a female being discovered when flying through a sunspot. There was no evidence that territorial residents were more attractive per se, with females seen to reject them as often as non-residents. Furthermore, in the cases where females were discovered outside of the sunspot, they were just as likely to mate with non-residents as residents. We hypothesize that the proximate advantage of territory ownership is that light conditions in a large sunspot greatly increase the male's ability to detect and intercept passing receptive females.

Use of fluoxetine to treat stereotypical pacing behavior in a brown bear (Ursus arctos)

Abstract A 12-year-old, male, brown bear ( Ursus arctos ) named Abdi exhibited stereotypical pacing behavior. He was kept as a pet for 10 years by local villagers, then he was rescued and taken to the Karacabey Bear Sanctuary in July 2001. His physical condition was extremely poor. Because he had never lived with other bears, he was terrified and refused to integrate with them. After 6 months he was healthy physically but observations by the keepers indicated that he was pacing all day. He was treated with fluoxetine (0.62 mg/kg orally every 24 hours) for 6 months, and had been observed totally for 18 months. After stereotypy ceased completely, he was transferred to the large naturalistic enclosure and did not show any stereotypical behavior during the subsequent observation period (1 year). He was treated successfully using a combination of fluoxetine, the provisioning of extra space, and the addition of novel stimulation in a naturalistic enclosure. The space and stimulation could be sufficient to mimic the therapeutic effect of the pharmacological therapy in the long term.

Experimental investigation in the TOSQAN facility of heat and mass transfers in a spray for containment application

TOSQAN is an experimental program undertaken by the Institut de Radioprotection et de Sûreté Nucléaire (IRSN) in order to perform thermal hydraulic containment studies. The TOSQAN facility is a large enclosure devoted to simulate typical accidental thermal hydraulic flow conditions in nuclear-pressurized water reactor (PWR) containment. The TOSQAN facility which is highly instrumented with non-intrusive optical diagnostics is particularly adapted to nuclear safety CFD code validation. The present work is devoted to studying the interaction of a water spray injection used as a mitigation means in order to reduce the gas pressure and temperature in the containment, to produce gases mixing and washout of fission products. In order to have a better understanding of heat and mass transfers between spray droplets and the gas mixture, and to analyze mixing effects due to spray activation, we perform detailed characterization of the two-phase flow.

Investigation of mixed convection in a large rectangular enclosure

This experimental research investigates mixed convection and heat transfer augmentation by gaseous forced jets in a large enclosure, at conditions simulating those of passive containment cooling systems for Gen III+ passively safe reactors. The experiment is designed to measure the key parameters governing heat transfer augmentation by forced jets, and to investigate the effects of geometric factors, including the jet diameter, jet injection orientation, interior structures, and enclosure aspect ratio. The tests cover a variety of injection modes leading to flow configurations of interest for mixing and stratification phenomena in containments under accident conditions. Correlations for heat transfer augmentation by forced jets are developed and compared with experimental data. The characteristic recirculation speed inside the enclosure is introduced and analyzed. Steady stratified temperature distributions are compared with model simulations of the BMIX++ code.

Influence of enclosure size and animal density on fecal cortisol concentration and aggression in Père David’s deer stags

We investigated the impact of enclosure size and animal density on behavior and adrenocortical secretion in Père David’s deer in Dafeng Nature Reserve, China. From February 15 to April 16 in 2004, we conducted two experiments. First, we studied maintenance behavior and conflict behavior of Père David’s deer stags in a large enclosure (200 ha) with low animal density (0.66 deer/ha) and a small display pen (0.75 ha) with high animal density (25.33 deer/ha). The maintenance behavior we recorded included standing, locomotion, foraging and rest. During the behavioral observations, we collected fresh voided fecal samples from the stags periodically, and analyzed the fecal cortisol concentrations in those samples using radioimmunoassay technique. Second, we monitored the fecal cortisol concentrations of one group of stags (12 deer lived in an enclosure of 100 ha) before and after transferred into a small pen (0.5 ha). We found that in the first experiment: (1) there were significant differences in standing and rest whereas no significant differences of locomotion and foraging between the free-ranging group and the display group; (2) frequency of conflict behavior in the display group was significantly higher than those in the free-ranging group; and (3) fecal cortisol concentration of the display group (326.17 ± 16.98 ng/g dry feces) was significantly higher than that of the free-ranging group (268.98 ± 15.21 ng/g dry feces). In the second experiment, there was no significant difference of the fecal cortisol concentrations among sampling days, but the mean fecal cortisol concentration of the day after transferring (337.46 ± 17.88 ng/g dry feces) was significantly higher than that of the day before transferring (248.44 ± 7.99 ng/g dry feces). Comparison with published findings, our results indicated that enclosure size and animal density affect not only behaviors, but also adrenocortical secretion in Père David’s deer. Small living space with high animal density may impose physiological stress to captive Père David’s deer. Moreover, long-term physiological stress and increase of conflict behavior may subsequently affect survival and reproduction of the deer.

Seasonal changes in mineral intake and first antler growth in Iberian red deer (Cervus elaphus hispanicus)

Iberian red deer (Cervus elaphus hispanicus) are mixed feeders with a broad food spectrum, consisting of grasses, shrubs, forbs and trees, depending on the habitat and season. In order to compensate possible deficiencies, deer are known to change diet as a response to seasonal changes in food availability and quality. In Mediterranean environments, summer is a period of decreasing forage quantity and quality that coincides with lactation and antlerogenesis, two highly mineral demanding events in deer physiology. Furthermore, most natural pastures are deficient in minerals essential for growth and reproduction (e.g. Na and Mg). Our objective was to determine the preferences, timing of intake and effects of essential minerals on antler growth and density of 9 male Iberian red deer calves.During the study, both experimental (E: n=5) and control (C: n=4) groups had ad libitum access to barley straw and meal from barley, maize, alfalfa, oat, and sugar beets (16 % crude protein; 11% humidity), pasture and water. There was no fasting before the experiments. The experiment took place at the Universidad de Castilla-La Mancha experimental farm (Albacete, Spain) from April 2005 (spring) to October 2006 (fall). Bowls with minerals were placed and weighed weekly in a small experimental shed (20m2) within a larger enclosure (10,000m2) where the experimental deer group was kept. Preferences for different compounds were examined in multiple-choice tests with I, Cu, Se and Zn compounds added to NaCl, while KCl, MgO, FeCO3, CaCO3, NaCl and Ca3(PO4)2 were placed unmixed each in a different bowl. In addition, animals were weighed and the main events related to first antler growth were recorded every fortnight. Mineral intake values are expressed in mg/d per animal. Differences between both animal groups were examined using a one-way ANOVA.We found that seasonal (spring-summer) ingestion was biased towards Na and CaCO3 (504 and 91 mg/d vs 162 and 19 mg/d in autumn-winter, respectively); intake of Ca3(PO4)2, K, Mg, I and Se were higher during the suckling period (728, 23, 23, 3 and 3mg/d, respectively); whilst Fe, Zn and Cu showed a clear decreasing trend over time. Antler specific gravity (g dry matter/mL; E: 1.15±0.05; C: 1.11±0.07), antler volume (E: 171±52mL; C: 168±38mL) and antler weight (E: 196±54g; C: 188±53g) were somewhat higher in the group with mineral supplementation, but differences were not significant. Additionally, date and weight of main events on antler growth varied among groups. Therefore, for the design of a proper nutrition plan particular mineral necessities of deer relative to age and physiological state might have to be considered.

The structure of social relationships among captive female giraffe (Giraffa camelopardalis).

Giraffe herds have been characterized as random associations of individuals, but recent evidence suggests giraffe have a more complex social structure. The authors formulated 3 hypotheses designed to evaluate whether a herd of captive giraffe (Giraffa camelopardalis) associated randomly or patterned their behavior and proximity in a manner indicative of social relationships. Affiliative interaction, proximity, and nearest neighbors for 6 captive female giraffe living in a large outdoor enclosure were analyzed, and all three measures were nonrandomly distributed, indicating female giraffe had social preferences. Furthermore, preferences were consistent across measures and time, suggesting that adult female giraffe maintain relationships. Mother-daughter pairs and pairs with large age differences between members interacted and associated most often. The social structure of this captive herd is influenced by social relationships between individual adult females, and the social behavior of individual females should be examined more closely in the wild.

Response of phytoplankton to ecological restoration in eutrophic lakes:an experimental large enclosure in Wuli Lake, Lake Taihu

根据太湖五里湖湾生态重建大型围隔示范工程的现场观测结果, 分析了湖泊生态重建措施对浮游植物的影响, 结果显示:(1)在生态重建的第一年, 尽管生态重建区内种植了大量水生植物, 水体氮磷含量也有较大幅度的下降, 水体透明度也被提高了近一倍, 但是藻类却大量生长, 并暴发了蓝藻水华;第二年, 生态重建区的环境条件逐渐对藻类(包括蓝藻和其中的微囊藻)产生了抑制作用, 开始出现藻类生物量下降趋势;表明生态重建措施(以水生植被重建为中心的生态系统重建组合措施)可以在较短时间内(当年)建立起一定规模的水生植物群落, 有效降低水体氮磷营养盐, 提高水体透明度, 但要在较短时间内(2年内)完善一个较大的水生态系统结构、有效降低藻类生物量(特别是夏季)有一定困难。(2)尽管氮磷营养盐对水体藻类总量增加有较大影响, 但并不是蓝藻大量暴发的决定因素, 上行作用力对蓝藻的控制(bottom-up effort)表现弱于下行作用力(top-down effort)。(3)较低的TN/TP比值(15.9-35.6, 平均30.5)既是蓝藻水华暴发的原因, 也是其作用的结果, 其可能有利于蓝藻的大量暴发。(4)生态重建措施较大幅度地改善了水环境, 但并没有显著提高藻类多样性指数(Shannon index), 因此, 单凭藻类多样性指数并不能完全反映水环境改善状况, 在评价水环境质量方面需要结合其它多种指标进行综合评估。;Response of phytoplankton to ecological restoration was evaluated based on the results of an experimental large enclosure in eutrophic Wuli Lake of Lake Taihu, China. The results indicated that in the first year of restoration, algal biomass significantly increased, and cyanobacteria blooms broke out although the coverage of aquatic plant was up to 55%; TN and TP were significantly decreased, and secchi depth was enhanced by 100% or so. In the next year, algal growth, including cyanobacteria and Microcystis, was inhibited in certain extent with improvement of environment in enclosure compared with that in the lake area (outside enclosure, a control area). The result showed that response of phytoplankton to ecological restoration was a slow process. Higher TN and TP were not decisive factors for the breakout of cyanobacteria biomass though the increase of total algal biomass was caused by higher nutrition (TP). Bottom-up effort was weaker than top-down effort. The lower TN to TP ratio possibly facilitated cyanobacteria growth, which was the cause and the result of cyanobacteria growth. In addition, the algal diversity index (Shannon index) was not totally indicating aquatic environment improvement status. It was suggested that it needed to integrate many factors for evaluating the trend of ecosystem.

A note on enrichment for captive lion-tailed macaques (Macaca silenus)

Two enrichment techniques were devised with the aim of reducing stress and improving welfare for captive lion-tailed macaques in an Indian zoo. In Study A, a log, cotton ropes and a feeding basket were added to the enclosures in different combinations to provide structural and feeding enrichment and were subsequently removed, while in Study B, singly-housed individuals were transferred to a large open-moated enclosure in which they were group-housed. The effects of these two enrichment techniques (social and physical) appeared to significantly improve the welfare of the study individuals by stimulating them to exhibit higher levels of natural behaviours along with the suppression of several abnormal behaviours.