Three-dimensional analyses of vascular network morphology in a murine lymph node by X-ray phase-contrast tomography with a 2D Talbot array.

With growing molecular evidence for correlations between spatial arrangement of blood vasculature and fundamental immunological functions, carried out in distinct compartments of the subdivided lymph node, there is an urgent need for three-dimensional models that can link these aspects. We reconstructed such models at a 1.84 µm resolution by the means of X-ray phase-contrast imaging with a 2D Talbot array in a short time without any staining. In addition reconstructions are verified in immunohistochemistry staining as well as in ultrastructural analyses. While conventional illustrations of mammalian lymph nodes depict the hilus as a definite point of blood and lymphatic vessel entry and exit, our method revealed that multiple branches enter and emerge from an area that extends up to one third of the organ's surface. This could be a prerequisite for the drastic and location-dependent remodeling of vascularization, which is necessary for lymph node expansion during inflammation. Contrary to corrosion cast studies we identified B-cell follicles exhibiting a two times denser capillary network than the deep cortical units of the T-cell zone. In addition to our observation of high endothelial venules spatially surrounding the follicles, this suggests a direct connection between morphology and B-cell homing. Our findings will deepen the understanding of functional lymph node composition and lymphocyte migration on a fundamental basis.

Use of passive radio frequency identification technologies to monitor nest usage in the northern carmine bee-eater (Merops n. nubicus).

The use of radio frequency identification (RFID) technology is common in animal-monitoring applications in the wild and in zoological and agricultural settings. RFID is used to track animals and to collect information about movements and other behaviors, as well as to automate or improve husbandry. Disney's Animal Kingdom® uses passive RFID technology to monitor nest usage by a breeding colony of northern carmine bee-eaters. We implemented RFID technologies in various equipment configurations, initially deploying low-frequency (LF) 125 kHz RFID and later changing to high-frequency (HF) 13.56 MHz RFID technology, to monitor breeding behavior in the flock. We installed antennas connected to RFID readers at the entrances of nest tunnels to detect RFID transponders attached to leg bands as birds entered and exited tunnels. Both LF-RFID and HF-RFID systems allowed the characterization of nest visitation, including the timing of nest activity, breeding pair formation, identification of egg-laying females, participation by nonresidents, and detection of nest disruptions. However, we collected a substantially larger volume of data using the increased bandwidth and polling speed inherent with HF-RFID, which permitted tag capture of multiple birds simultaneously and resulted in fewer missed nest visits in comparison to LF-RFID. Herein, we describe the evolution of the RFID setups used to monitor nest usage for more than 7 years, the types of data that can be gained using RFID at nests, and how we used these data to gain insights into carmine bee-eater breeding behavior and improve husbandry.

Application of video recording technology to improve husbandry and reproduction in the carmine bee-eater (Merops n. nubicus).

Incorporating technology with research is becoming increasingly important to enhance animal welfare in zoological settings. Video technology is used in the management of avian populations to facilitate efficient information collection on aspects of avian reproduction that are impractical or impossible to obtain through direct observation. Disney's Animal Kingdom(®) maintains a successful breeding colony of Northern carmine bee-eaters. This African species is a cavity nester, making their nesting behavior difficult to study and manage in an ex situ setting. After initial research focused on developing a suitable nesting environment, our goal was to continue developing methods to improve reproductive success and increase likelihood of chicks fledging. We installed infrared bullet cameras in five nest boxes and connected them to a digital video recording system, with data recorded continuously through the breeding season. We then scored and summarized nesting behaviors. Using remote video methods of observation provided much insight into the behavior of the birds in the colony's nest boxes. We observed aggression between birds during the egg-laying period, and therefore immediately removed all of the eggs for artificial incubation which completely eliminated egg breakage. We also used observations of adult feeding behavior to refine chick hand-rearing diet and practices. Although many video recording configurations have been summarized and evaluated in various reviews, we found success with the digital video recorder and infrared cameras described here. Applying emerging technologies to cavity nesting avian species is a necessary addition to improving management in and sustainability of zoo avian populations.

Reproductive and parental behavior in Taveta golden weavers (Ploceus castaneiceps).

Taveta golden weavers are popular in zoos, but little has been published on their reproduction, social behavior, or other aspects of their management. At Disney's Animal Kingdom® , we have had great success with our breeding program and house a large flock in our mixed-species walk-through Africa aviary and smaller groups in the off-exhibit Avian Research Center. We conducted observations on both groups in order to document behavioral differences between the groups living under differing management conditions. Data on which individuals were inside, on or near focal nests were collected using a 30-s scan samples. Scan data were analyzed using a two-factor ANOVA, with aviary location and nest contents as the factors. We found that, in both aviary locations, females spent more time inside and on the nests than males did. As expected, females spent more time inside the nests containing eggs and more time on the nests containing chicks, likely due to incubation and chick-feeding demands, respectively. Interestingly, we found that females spent significantly more time inside their nests and males spent more time near their nests in the Africa aviary than in ARC. Despite Africa aviary's higher nest attendance, a higher proportion of nests fledged chicks in ARC (72% vs. 41%). These data are consistent with findings in wild sociable weavers [Spottiswoode, 2007. Oecologia 154: 589-600]. Future work with zoo-housed populations of weavers could help shed light on this phenomenon, which is not yet well understood. A better understanding of the consequences of different group sizes and housing conditions could have important implications for how Taveta weavers are managed.

The effect of changes in group composition on social dynamics in marabou storks (Leptoptilos crumeniferus).

The reduction of aggressive behaviors can be a concern whenever animals are socially housed, but for some species, such as marabou storks, zoos are still unsure of the best management strategies. To learn more about marabou behavior and how dynamics change as group composition changes, we monitored a total of 3.5 marabous as individuals were added and removed over 2 years. We found that, in mixed-sex groups, males were more likely to be the initiators of displacements and females were more likely to be the recipients. Most contact aggression was intra-sexual, and females engaged in contact aggression more often than males. The highest levels of aggression were seen in our all-female groups, which was unexpected given the high number of male attacks on females reported in zoos. Because females were being added and removed but our males remained the same throughout the study, we are unsure whether this was due to a higher level of instability among females or a true sex difference; regardless, these data highlight the need to monitor aggression even within all female stork groups. Overall, we observed low levels of inter-sexual aggression, suggesting that some fatal attacks may be due, in part, to non-social factors, such as enclosure design. Social birds like marabous may benefit from the same type of group management approach that is commonly utilized with other social taxa. A two-pronged approach of observation and management of marabou social dynamics and some modification of their enclosure structure may limit injurious aggression in the future.

The use of visual barriers to reduce aggression among a group of marabou storks (Leptoptilos crumeniferus).

Marabou storks are one of the most commonly held birds in zoos, but the captive population faces challenges related to high mortality. One of the most common causes of death among captive marabou storks is conspecific aggression. There is a pressing need to better understand how to manage this aggression. One method that has been used successfully to reduce aggression in other species is the addition of visual barriers to the enclosure, though there are no published studies on their effect on storks. We studied the behavioral changes in a group of 2.2 marabou storks following the addition of two shade cloth barriers to their enclosure; we documented all occurrences of aggressive behavior, as well as time spent proximate to the barriers (or the space between barrier posts, when the shade cloth was removed) and time spent using the barriers to block the view of other storks. The presence of the shade cloth did not change the amount of time storks spent proximate to the barriers, nor did they spend more than 2% of their time using the barriers to block other storks, but the presence of the barriers significantly reduced displacement activity. Barriers may afford captive marabou storks an important means of escaping conflict, as flight-restriction and housing in an enclosure can limit their opportunities to give a signal of retreat or submission.

Identifying parentage using molecular markers: improving accuracy of studbook records for a captive flock of marabou storks (Leptoptilos crumeniferus).

Extra-pair copulations (EPCs) leading to extra-pair fertilization (EPF) are common in avian mating systems, despite the prevalence of observed social monogamy in many species. Colonially breeding birds are interesting species to investigate the prevalence of EPCs and EPF because they show nesting habits including close proximity of nest sites and sexual partners, which are proposed to promote alternative reproductive tactics. Endemic to Africa, the colonial marabou stork (Leptoptilos crumeniferus) is one of the most commonly held avian species in North American zoos. The aims of this study were to use genetic information to verify parentage in a population of marabou stork housed at Disney's Animal Kingdom® based on five microsatellite loci and to investigate reproductive behavior. We compared genetic analyses of parents and offspring to studbook data collected through behavioral observations of parental behavior at the nest. Using genetic analyses to reconstruct the pedigree of the marabou stork flock using the program COLONY led to improvement of studbook records by determining parentage of an individual that had previously unknown parentage, and identified one individual that had a sire that differed genetically from studbook records. An important contribution of our analyses was the identification and verification of the most likely parents for offspring hatched in this colony and improving incorrect or undocumented parentage in the studbook. Additionally, the colonial nature of this species makes it difficult to observe and understand reproductive behavior. Gaining better understanding of the mating system of a species is essential for successful breeding and captive management.

Hand-rearing and sex determination tool for the Taveta golden weaver (Ploceus castaneiceps).

Improvements in the ability to hand-rear birds in captivity have aided zoological institutions in the sustainable management of these species, and have provided opportunities to examine their physical growth in varying conditions. Monitoring the weight gain and development of chicks is an important aspect of developing a hand-rearing protocol. In this paper we provide the institutional history for a colonial species of passerine, the Taveta golden weaver, at Disney's Animal Kingdom®, in order to demonstrate the methods of establishing a successful breeding program which largely incorporates hand-rearing in management of the population. We also tested if we could accurately predict sex of chicks using weights collected on Day 14 during the hand-rearing process. Using this tool, we were able to correctly determine sex before fledging in more than 83% of chicks. Early sex determination is important in captive species for genetic management and husbandry purposes. While genetic sexing can be expensive, we found that using growth curves to determine sex can be a reliable and cost-effective tool for population management of a colonial passerine.

Approach/avoidance motives, test emotions, and emotional regulation related to testing.

This research stems from our program of work that focuses on understanding how students regulated their emotions related to testing. The primary goal for this study was to incorporate the approach/ avoidance motives into a model of emotional regulation related to testing. In addition, a secondary goal was to report on efforts at construct validation of the scores obtained during the refinement of the Emotional Regulation Related to Testing (ERT) Scale. Our results suggest that underlying beliefs, such as approach/avoid motives and the cognitive-appraisal process, of the ERT had both direct and indirect effects to both pleasant and unpleasant emotions related to testing. In addition, the ERT accounted for 56% of the variance in Pleasant and 87% of Unpleasant Test Emotions.