Lion,Ungulate, and Visitor Reactions to Playbacks of Lion Roars at Zoo Atlanta

Felids in captivity are often inactive and elusive in zoos, leading to a frustrating visitor experience. Eight roars were recorded from an adult male lion and played back over speakers as auditory enrichment to benefit the lions while simultaneously enhancing the zoo visitor experience. In addition, ungulates in an adjacent exhibit were observed to ensure that the novel location and increased frequency of roars did not lead to a stress or fear response. The male lion in this study roared more in the playback phase than in the baseline phases while not increasing any behaviors that would indicate compromised welfare. In addition, zoo visitors remained at the lion exhibit longer during playback. The nearby ungulates never exhibited any reactions stronger than orienting to playbacks, identical to their reactions to live roars. Therefore, naturalistic playbacks of lion roars are a potential form of auditory enrichment that leads to more instances of live lion roars and enhances the visitor experience without increasing the stress levels of nearby ungulates or the lion themselves, who might interpret the roar as that of an intruder.     

Association between gravitational force and tissue metabolism in periparturient rats

Recently, interest in mammalian reproduction and offspring survival in altered gravity has been growing. Because successful lactation is critical for mammalian neonate survival, we have been studying the effect of gravity metabolism. We have shown an exponential relationship between glucose metabolic rate in mammary tissue of periparturient rats and an increase in gravity load. In this study we showed that changes in mammary metabolic rate due to gravity force were accompanied by a decrease in glucose metabolism in adipose tissue and by a reduced size of adipocytes. We assume that these changes are likely due to changes in prolactin or leptin levels related to altered gravity load.     

Retreat space and human visitor density moderate undesirable behavior in petting zoo animals

This study focused on the relationship between nonhuman animal behavior and environment-specifically, between the undesirable behavior exhibited by domestic petting zoo animals in the presence of humans and the spatial design of the petting zoo environment. A spatial feature of a petting zoo referred to as a retreat space was manipulated so that it affected the animals' opportunity for individual control over interaction with humans. Three conditions were tested: no retreat space, semi-retreat space, and a full-retreat space. The subjects of this study were 5 African pygmy goats (Capra hircus) and 2 Romanov sheep (Ovis aries). Investigators used a focal sampling technique to analyze approximately 27 hr of behavioral data collected. The data were analyzed using multiple linear regression methods. The findings suggest that the full-retreat design beneficially moderated both sheep and goat behavior: Undesirable behaviors were lowest in the full-retreat condition. This study provides information that may improve human-animal interactions in a petting zoo setting and may increase animal well-being through exhibit design and management techniques.     

Naturally Occurring Genetic Variants in Human Chromogranin A (CHGA) Associated with Hypertension as well as Hypertensive Renal Disease

Chromogranin A (CHGA) plays a fundamental role in the biogenesis of catecholamine secretory granules. Changes in storage and release of CHGA in clinical and experimental hypertension prompted us to study whether genetic variation at the CHGA locus might contribute to alterations in autonomic function, and hence hypertension and its target organ consequences such as hypertensive renal disease (nephrosclerosis). Systematic polymorphism discovery across the human CHGA locus revealed both common and unusual variants in both the open reading frame and such regulatory regions as the proximal promoter and 30-UTR. In chromaffin cell-transfected CHGA 30-UTR and promoter/luciferase reporter plasmids, the functional consequences of the regulatory/non-coding allelic variants were documented. Variants in both the proximal promoter and the 30-UTR displayed statistical associations with hypertension. Genetic variation in the proximal CHGA promoter predicted glomerular filtration rate in healthy twins. However, for hypertensive renal damage, both end-stage renal disease and rate of progression of earlier disease were best predicted by variants in the 30-UTR. Finally, mechanistic studies were undertaken initiated by the clue that CHGA promoter variation predicted circulating endothelin-1. In cultured endothelial cells, CHGA triggered co-release of not only the vasoconstrictor and pro-fibrotic endothelin-1, but also the pro-coagulant von Willebrand Factor and the pro-angiogenic angiopoietin-2. These findings, coupled with stimulation of endothelin-1 release from glomerular capillary endothelial cells by CHGA, suggest a plausible mechanism whereby genetic variation at the CHGA locus eventuates in alterations in human renal function. These results document the consequences of genetic variation at the CHGA locus for cardiorenal disease and suggest mechanisms whereby such variation achieves functional effects.     

Behavioral and hormonal consequences of transporting giant pandas from China to the United States

Zoological institutions strive to ensure the welfare of nonhuman animals in captivity. Part of this effort involves reducing the level of distress experienced by an animal to the greatest extent possible. However, some necessary zoo management practices such as transportation induce stress responses. An extensive literature exists concerning the animal welfare implications of road transportation for farm and laboratory animals. There has, however, been little focus on the effects of air transportation on wild animals in captivity. Because many endangered species are transported by air for breeding purposes, it is especially important to study the effects of stress on these species. This study investigated the behavioral and hormonal consequences of transporting 4 giant pandas (2 male-female pairs) by air from China to the United States. An autoregressive test revealed that urinary cortisol measures were highest for 2 subjects, Lun Lun and Tian Tian, during the flight than during the remainder of the 30-day period posttransport (p < .01). No long-term behavioral changes or problems emerged as a result of the transport. The study found that more research is needed to develop a complete understanding of transportation stress and welfare in captive wildlife.     

The cannabinoid CB1 receptor is expressed in pancreatic delta-cells

Antagonists of cannabinoid CB1 receptor (CB1, CNR1) promote weight loss and decrease hyperglycemia in patients with type 2 diabetes. While the endocannabinoid system may modulate islet hormone secretion, the cell-type expressing CB1 receptor in islets has not been fully resolved. In this study, we verified receptor gene expression in rodent islets and cell lines and examined the distribution of CB1 receptor in mouse, rat, and human islets by confocal immunofluorescence (IF) microscopy. IF demonstrated CB1 receptor was present in β-cell lines, but co-localized solely with somatostatin in the islet δ-cells of Zucker rats, C57BL/6 mice, and humans; no CB1 receptor expression was observed in α-, β-, or pp-cells. Similarly, a rat somatostatinoma cell line, MSL-G2-Tu6, was found to express CB1 receptor. We also found monoacylglycerol lipase (MAGL) to be expressed in δ-cells and fatty acid amide hydrolase (FAAH) to be expressed in α-cells. The specific expression of CB1 in δ-cells suggests that the ECS may play a role in modulating islet hormone secretion. As there are some differences between our findings and previous reports, further studies, including detailed physiological studies of the effects of the ECS on islet function, are warranted.     

Successful feeding enrichment for captive chimpanzees

An analysis of a feeding enrichment program for captive chimpanzees was completed to determine the effects of that program on the incidence of agonistic and abnormal behaviors by using 41 adult chimpanzees in six social groups. Four feeding enrichment procedures were implemented simultaneously in the experimental phase of this ABA design study. The procedures were planned to elicit time-consuming, noncompetitive feeding, theorizing a consequent reduction in agonism and detrimental abnormal behaviors typically occurring in captive chimpanzees. The 270 hours of data were collected over a 6-month period. A multivariate analysis of variance result supported the hypothesis, as the barrage of feeding enrichment techniques significantly reduced agonism and abnormal behaviors. This study's significance lies in its application of the scientific method to improving the husbandry of captive primates.