Jairo Muñoz-Delgado

Astronomical and meteorological parameters and rest-activity rhythm in the Spider monkey Ateles geoffroyi

UNLABELLED All animals including primates show regular variations in their behavioural activities and physiological functions. In numerous species diel, ultradian, infradian, annual and/or lunar rhythms have been established; however, the use of the focal sampling method does not provide information on hour-to-hour nor day-to-day variations. In behavioural field studies dealing with primate activity rhythms and their modulation by environmental variables the possible dual, synchronizing and/or masking effect of these variables is often ignored. In the present study, we analyze the relation between astronomical and meteorological parameters and various parameters of the rest-activity rhythm in Ateles geoffroyi, a species scarcely investigated with respect to biological rhythms. These Ateles were kept under semi-natural conditions, exposed to natural light, temperature and humidity cycles, and sky state. Motor activity was recorded with actiwatch accelerometers during 180 days (5-min intervals), starting from the autumn equinox. RESULTS Ateles is active throughout the day, rests during the night and presents bimodal activity. Activity time, onset and end of activity as well as the times of their two activity peaks were significantly correlated with duration of the solar day and sunrise or sunset time. The behavioural parameters also correlated with ambient temperature. Climate factors and sky-state significantly influenced the duration and times of onset and end of activity. Our findings identified a clear modulation of the rest-activity pattern by astronomical variables serving as Zeitgebers, such as the natural light-dark cycle, and by masking effects of meteorological factors (temperature, weather and cloudiness), as well as of artificial variables introduced by the interaction with man.

Environmental enrichment for captive stumptail macaques (Macaca arctoides).

Background  The behavior of animals is modified by captivity. Environmental enrichment (EE) is a program designed to enhance the welfare of confined animals by providing them with a more stimulating background. This is carried out by the implementation of a series of activities that encourages them to present behaviors typical of their species, as well as keeps them active. The aim of this study was the evaluation of the influence of the EE in the behavioral variables in a colony of 24 stumptail macaques (Macaca arctoides). Our hypothesis is that the application of this program will reduce aggression, stereotypes and coprophilia behaviors and, at the same time, will increase exploration and solitary play.

Novelty-Seeking Temperament in Captive Stumptail Macaques (Macaca arctoides) and Spider Monkeys (Ateles geoffroyi)

Novelty-seeking temperament is defined as the reaction to novel or risk situations and objects, and by the global disposition to explore such stimuli. Our purpose was to describe and compare this trait in primates. For this purpose, a risk-taking Index, a curiosity index, and a novelty-seeking index were correlated to several biosocial variables using 22 captive stumptail macaques (Macaca arctoides) and 7 captive spider monkeys (Ateles geoffroyi). Spider monkeys scored higher than macaques, males of both species scored higher than females, and dominant macaques were evaluated as more novelty seekers. We suggest that these differences may be because of, among other reasons, the particular social system of each species.

Sleep and rest activity measured by wrist actigraphy in an HIV-infected patient with Steven–Johnson syndrome

The Steven–Johnson syndrome (SJS) is characterized by a sudden onset of mucous membrane erosion (predominantly oral mucosa, lips, and conjunctivae) with widespread blistering of the skin involving up to 10% of the body surface area. It is almost always a drug-related reaction, although it can be caused by infections and immunizations. A 33-year-old man with recent diagnosis of HIV infection developed antiretroviral treatment (ART)-associated SJS. Physical activity and sleep parameters were recorded by wrist actigraphy in four different consecutive scenarios: baseline assessment, first ART regimen, hospitalization, and second ART regimen. Significant differences were observed in physical activity patterns between the four phases. No differences in sleep parameters were found. To our knowledge, this is the first study recording physical activity changes and sleep during a SJS reaction.

Tractography of the Spider Monkey (Ateles geoffroyi) Corpus Callosum Using Diffusion Tensor Magnetic Resonance Imaging

The objective of this research was to describe the organization, connectivity and microstructure of the corpus callosum of the spider monkey (Ateles geoffroyi). Non-invasive magnetic resonance imaging and diffusion-tensor imaging were obtained from three subjects using a 3T Philips scanner. We hypothesized that the arrangement of fibers in spider monkeys would be similar to that observed in other non-human primates. A repeated measure (n = 3) of fractional anisotropy values was obtained of each subject and for each callosal subdivision. Measurements of the diffusion properties of corpus callosum fibers exhibited a similar pattern to those reported in the literature for humans and chimpanzees. No statistical difference was reached when comparing this parameter between the different CC regions (p = 0.066). The highest fractional anisotropy values corresponded to regions projecting from the corpus callosum to the posterior cortical association areas, premotor and supplementary motor cortices. The lowest fractional anisotropy corresponded to projections to motor and sensory cortical areas. Analyses indicated that approximately 57% of the fibers projects to the frontal cortex and 43% to the post-central cortex. While this study had a small sample size, the results provided important information concerning the organization of the corpus callosum in spider monkeys.

Recording vocalizations with Bluetooth technology.

We propose a method for capturing vocalizations that is designed to avoid some of the limiting factors found in traditional bioacoustical methods, such as the impossibility of obtaining continuous long-term registers or analyzing amplitude due to the continuous change of distance between the subject and the position of the recording system. Using Bluetooth technology, vocalizations are captured and transmitted wirelessly into a receiving system without affecting the quality of the signal. The recordings of the proposed system were compared to those obtained as a reference, which were based on the coding of the signal with the so-called pulse-code modulation technique in WAV audio format without any compressing process. The evaluation showed p < .05 for the measured quantitative and qualitative parameters. We also describe how the transmitting system is encapsulated and fixed on the animal and a way to video record a spider monkey’s behavior simultaneously with the audio recordings.

Season of Birth in Schizophrenia in the Mexico City Area: Comparison with General Population

The relationship between seasonal changes and mental disorders has been extensively studied in the northern and southern hemispheres. In both cases, the results show that there is a higher rate of schizophrenic births during the winter months. The present study attempts to prove the existence of this phenomena in Mexico City, an area that does not undergo extreme weather variations throughout the year. A total of 2,288 schizophrenic patients was considered for this study. Their date of birth was compared to that of the general population of the Mexico City area, a total of 4,848,119 individuals. The number of births was evaluated according to the number of days in each month. The distribution of the births of schizophrenics was compared to the reference population by means of a Kolmogorov-Smirnov test and a X 2 contrast. The annual rhythm of births of schizophrenics was determined through an analysis of the Estimated Seasonal Component. There was a slight, non-significant increment in schizophrenic births in December and autumn, as compared with the general population birth rate. Interestingly, it was found that births in the control population decreased significantly in December when compared with all the other months. Results were discussed in relation to the geographical location of Mexico, which lies in a tropical zone, and as a consequence minimal seasonal effects.

Variations in the locomotor activity of the Mexican wolf (Canis lupus baileyi) respect to moon periodicity: a study in an outdoor enclosure

Abstract It is assumed that the response of the regulatory system of mammal activity depends on the changes in light intensity throughout the 24-h cycle. The aim of this study was to determine whether the moon luminosity cycle exerts an effect on the locomotor activity of the Mexican wolf (C. lupus baileyi). Data collection was carried out with the actimetry, of 11 individuals were analyzed using ANOVA to determine the effect of the lunar cycle. Significant differences were encountered between moon phases (p = 0.001), with a decrement of activity during new and full moon. However, effects were dependent also on the age of the individuals and the daylight period. On the other hand, it is a possible regulation of the activity pattern by the effect of lunar periodicity. This periodicity needs a more detailed examination to determine its adaptive function.

Lunar and Seasonal Rhythms and Childhood Mortality

The aim of the present study was to assess the effect of the lunar cycle phases, the lunar apogee and perigee, and the geophysical factors (humidity, temperature, and rainfall) on the childhood mortality. We designed a retrospective study by reviewing the clinical charts of the population of patient deceases during the lunar pre-phase (a day before), phase (day of lunar change of phase), and post-phase (a day after), between the years 1991–1996 in a children’s hospital. From the 44,982 discharges from the hospital in the interval between 1991 and 1996, 2003 corresponded to mortal cases, and 522 died within the 3 days we considered as representative for each phase. The number of deaths was approximately the same in between phases. The percentage of male deaths was higher during phase days than interphase ones. Male deceases exhibited a statistically significant predominance during lunar first quarter, full moon, and new moon. A discreet increase of mortality was present in the months of March, June, August, September, October, and November, as well as during summer and fall, but these increments were not significant. Minimum and maximum temperatures exhibited no relation to this behavioral pattern for deceases, nor the humidity index. Early lactating infants presented a significant higher mortality during November, December, and March. We suggest to investigate the causes of the increase of deceases in males in relation to the circalunar rhythms, as well as the lift up of deceases in neonates and early lactating children during November and December.

Circadian and ultradian activity rhythms in manatee (Trichechus manatus manatus) in captivity

In this study, we show temporal organization of activity patterns in larger temporal series recording. The objective of this study was to determine the temporal pattern of the rest-activity rhythm in manatee (Trichechus manatus manatus) in captivity. Activity recordings were programmed from August 2010 to September 2011 with actimetry devices, and behavior recordings were conducted in dry and rainy seasons. We showed that the marine manatee presents a complex temporal organization, in which the rest-activity rhythm comprises several frequencies with a predominant circadian component and multiple ultradian components. Our results indicate that the animals were more active during the day with respect to the night. The temporal organization of this cycle entails multiple frequencies that include ultradian rhythms, which may be expressions generated by physiological needs, such as food availability and thermoregulatory requirements. These patterns should be taken into consideration for future studies of biological rhythms in manatee.