Zoo visitors affect sleep, displacement activities, and affiliative and aggressive behaviors in captive ebony langurs (Trachypithecus auratus)

Previous studies have shown that the number, noise level, and activity level of zoo visitors can negatively influence the behavior of captive animals. This study combined these three factors into a single visitor impact score and assessed whether visitor impact predicted the frequency or occurrence of displacement activities, affiliative behaviors, and aggression in a group […]

Sleep-related behaviors in zoo-housed giraffes (Giraffa camelopardalis reticulata): Basic characteristics and effects of season and parturition

Despite increasing interest in the behavior of zoo animals, studies of nocturnal behavior of zoo animals are limited. In this study, we investigated the relationship between parturition, season, and the sleep-related behaviors in captive reticulated giraffes to better understand the nocturnal life in giraffes. The subjects were two adult reticulated giraffes living in Kyoto City […]

Effects of blue- and red-enriched light on attention and sleep in typically developing adolescents

Differential effects of blue- and red-enriched light on attention and sleep have been primarily described in adults. In our cross-over study in typically developing adolescents (11–17 years old), we found attention enhancing effects of blue- compared to red-enriched light in the morning (high intensity of ca. 1000 lx, short duration: <1 h) in two of three attention tasks: […]

Behavioral patterns of laboratory Mongolian gerbils by sex and housing condition: a case study with an emphasis on sleeping patterns

The behavioral patterns of Mongolian gerbils (Meriones unguiculatus) housed individually and in same-sex groups (siblings) were characterized. Gerbils were continuously video-recorded 24 hours (day 1) and 120 hours (day 5) after housing conditions were established (no environmental enrichment was implemented). Video samples totaling 2016 minutes were scored to obtain measures of maintenance (drinking, sleeping, grooming, and eating), locomotor […]

Assessment of spontaneously occurring periodic limb movements in sleep in the rat

OBJECTIVE: Periodic limb movements in sleep (PLMS) are often associated with the restless legs syndrome (RLS). Although the dopaminergic system seems to be involved, the pathophysiology of PLMS and RLS is still obscure. The objective of this study is to explore whether a PLMS-like phenomenon can be observed in rodents in order to elucidate the […]

Animal models for information processing during sleep

Information provided by external stimuli does reach the brain during sleep, although the amount of information is reduced during sleep compared to wakefulness. The process controlling this reduction is called ‘sensory’ gating and evidence exists that the underlying neurophysiological processes take place in the thalamus. Furthermore, it is clear that stimuli given during sleep can […]

Investigation of the sleep electrocorticogram of the common marmoset (Callithrix jacchus) using radiotelemetry

OBJECTIVE: To evaluate the use of a totally implantable radiotelemetry system for recording the sleep electrocorticogram (ECoG) of a small new world primate, the common marmoset (Callithrix jacchus) without restraint during data collection. METHODS: Under anaesthesia a telemetry transmitter, which allowed the recording of a single ECoG channel, was implanted intraperitoneally. This system allowed ECoG […]

Assessing sleep state in calves through electrophysiological and behavioural recordings: A preliminary study

Adequate sleep is important for the health and well being of animals but we lack non-invasive methods to record sleep states from group-housed, freely-moving farm animals. We used electrophysiological data (electroencephalography; EEG, electromyography; EMG, and electro-oculography; EOG) to characterize sleep states in calves and examined how well observations of resting behaviour were correlated with the […]

Social stress induces high intensity sleep in rats

We studied the effect of social stress on sleep electroencephalogram (EEG) in rats. Animals were subjected to a single social defeat by introducing them in the cage of an aggressive male conspecific for 1 h. The animals responded to the social conflict by a sharp increase in EEG slow-wave activity (SWA) during non-rapid eye movement […]

Sleep and social status in captive gelada baboons (Theropithecus gelada)

Sleep was investigated in 10 captive gelada baboons (Theropithecus gelada), belonging to two harem groups by continuous infrared video recording (n = 4 males, n = 3 females, n = 3 juveniles). The aim was to investigate the relation between sleep and social status. Social status was assessed during daytime activities, when the two harem […]