4 resultados para Captivity

em Bucknell University Digital Commons - Pensilvania - USA


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White-nose syndrome (WNS) is an emerging infectious disease of hibernating bats linked to the death of an estimated 5.7 million or more bats in the northeastern United States and Canada. White-nose syndrome is caused by the cold-loving fungus Pseudogymnoascus destructans (Pd), which invades the skin of the muzzles, ears, and wings of hibernating bats. Previous work has shown that WNS-affected bats arouse to euthermic or near euthermic temperatures during hibernation significantly more frequently than normal and that these too-frequent arousals are tied to severity of infection and death date. We quantified the behavior of bats during these arousal bouts to understand better the causes and consequences of these arousals. We hypothesized that WNS-affected bats would display increased levels of activity (especially grooming) during their arousal bouts from hibernation compared to WNS-unaffected bats. Behavior of both affected and unaffected hibernating bats in captivity was monitored from December 2010 to March 2011 using temperature-sensitive dataloggers attached to the backs of bats and infrared motion-sensitive cameras. The WNS-affected bats exhibited significantly higher rates of grooming, relative to unaffected bats, at the expense of time that would otherwise be spent inactive. Increased self-grooming may be related to the presence of the fungus. Elevated activity levels in affected bats likely increase energetic stress, whereas the loss of rest (inactive periods when aroused from torpor) may jeopardize the ability of a bat to reestablish homeostasis in a number of physiologic systems.

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WNS-affected bats did so over similar time frames as WNSunaffected bats. The behaviors of bats with WNS did not change as drastically as expected. Thereseems to be little to no effect on their ability to fly/forage until much later stages of the disease when they are likely near death. WNS-affected bats are grooming more which could be altering the way they use energy reserves during hibernation possibly leading tostarvation and eventually death. The decreased likelihood of arousals in response to external cues may be the result of spending more energy during previous and increasingly frequent arousals. While it is clear that WNS does result in changes in behavior whether these changes are directly in response to fungal skin infection or to some other component of the syndrome such as decreased energy availability or loss of homeostasis is unknown. bat behavior, white-nose syndrome, behavior, video surveillance, arousal patterns White-Nose Syndrome (WNS) is a disease of hibernating bats caused by the fungal pathogen Geomyces destructans. The fungus, which was first noted in 2006, invades bats wings and other exposed membranes, eventually resulting in death. Researchers have yet to understand many aspects of this disease, including basic etiology and epidemiology. There is also a lack of information on how fungal infection may change the behavior of healthy bats during hibernation or how changes in behavior may influence disease progression. Based upon the physiological changes that are known to occur in affected bats, and upon anecdotal observations of aberrant behavior in these bats, I hypothesized that WNS would significantly change the behavior of the little brown myotis (Myotis lucifugus). My research examined the behavior of hibernating bats during arousals from torpor. I compared WNS-affected and unaffected bats, in the field and incaptivity, using motion-sensitive infrared cameras. Flight maneuverability and echolocation were also tested between WNS-affected and unaffected bats during arousalsfrom hibernation to detect changes in the bats' ability to perform basic locomotion or potentially catch insect prey. Lastly, hibernating bats were artificially disturbed and theirarousal patterns were monitored to examine changes in the response to external stimuli between WNS-affected and unaffected bats.Bats with WNS groomed for longer periods of time after arousing from torpor, both in the field and in captivity. They also engaged in longer periods of any sort of activity during these arousals. There were no changes in acoustical signaling during flight tests and changes in flight maneuverability were only found in bats were seen staging" near the entrance of the mine which is itself a unique behavior exhibited by affected bats. At this point these bats were likely near death and could barely fly at all. In response toexternal stimuli bats with WNS were less likely to arouse than unaffected bats. However when they did arouse WNS-affected bats did so over similar time frames as WNSunaffected bats. The behaviors of bats with WNS did not change as drastically as expected. Thereseems to be little to no effect on their ability to fly/forage until much later stages of the disease when they are likely near death. WNS-affected bats are grooming more which could be altering the way they use energy reserves during hibernation possibly leading tostarvation and eventually death. The decreased likelihood of arousals in response to external cues may be the result of spending more energy during previous and increasingly frequent arousals. While it is clear that WNS does result in changes in behavior whetherthese changes are directly in response to fungal skin infection or to some other component of the syndrome such as decreased energy availability or loss of homeostasis is unknown."

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Capuchin monkeys, Cebus sp., utilize a wide array of gestural displays in the wild, including facial displays such as lip-smacking and bare-teeth displays. In captivity, they have been shown to respond to the head orientation of humans, show sensitivity to human attentional states, as well as follow human gazes behind barriers. In this study, I investigated whether tufted capuchin monkeys (Cebus apella) would attend to and utilize the gestural cues of a conspecific to obtain a hidden reward. Two capuchins faced each other in separate compartments of an apparatus with an open field in between. The open field contained two cups with holes on one side such that only one monkey, a so-called cuing monkey, could see the reward inside one of the cups. I then moved the cups toward the other signal-receiving monkey and assessed whether it would utilize untrained cues provided by the cuing monkey to select the cup containing the reward. Two of four female capuchin monkeys learned to select the cup containing the reward significantly more often than chance. Neither of these two monkeys performed over chance spontaneously, however, and the other two monkeys never performed above chance despite many blocks of trials. Successful choices by two monkeys to obtain hidden rewards provided experimental evidence that capuchin monkeys attend to and utilize the gestural cues of conspecifics.

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White-nose syndrome (WNS) is a disease that has caused the mass mortality of hibernating bat species. Since its first discovery in the winter of 2006-2007, an estimated five million bats or more have been killed. Although infection with Pseudogymnoascus destructans (Pd, the causative agent of WNS) does not always result in death, bats that survive Pd infection may experience fitness consequences. To understand the physiological consequences of WNS, I measured reproductive rates of free-ranging hibernating bat species of the Northeastern United States. In addition, captive little brown myotis (Myotis lucifugus) bats that were infected by Pd but survived (¿WNS survivors¿) and uninfected bats were studied in order to understand the potential consequences (e.g., lower reproductive rates, decreased ability to heal wounds, degradation of wing tissue, and altered metabolic rates) of surviving WNS. No differences in reproductive rates were found between WNS-survivors and uninfected bats in either the field or in captivity. In addition, wound healing was not affected by Pd infection. However, wing tissue degradation was worse for little brown myotis 19 days post-hibernation, and mass specific metabolic rate (MSMR) was significantly higher for those infected with Pd 22 days post-hibernation. While it is clear that these consequences are a direct result of Pd infection, further research investigating the long-term consequences for both mothers and pups is necessary.