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Kirkpatrick, J. F., Vail, R., Devous, S., Schwend, S., Baker, C. B., & Wiesner, L. (1976). Diurnal variation of plasma testosterone in wild stallions. Biol Reprod, 15(1), 98–101. |
Collery, L. (1974). Observations of equine animals under farm and feral conditions. Equine Vet J, 6(4), 170–173. |
Nelson, G. S. (1970). Onchocerciasis. Adv Parasitol, 8, 173–224.
Keywords: Africa; Animals; Anthelmintics/therapeutic use; Artiodactyla; Blindness/etiology; Cattle; Circadian Rhythm; Ddt; Diethylcarbamazine/therapeutic use; Diptera/anatomy & histology/growth & development; Dwarfism/etiology; Ecology; Eye/pathology; Feeding Behavior; Female; Geography; Haplorhini; Hernia, Femoral/etiology; Horses; Humans; Insect Vectors/growth & development; Larva/growth & development; Male; Onchocerca/classification/growth & development; *Onchocerciasis/diagnosis/drug therapy/epidemiology/immunology/pathology/prevention & control/veterinary; Primates; Serologic Tests; Skin/pathology; Skin Tests; Suramin/therapeutic use
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Berger, A., Scheibe, K. - M., Eichhorn, K., Scheibe, A., & Streich, J. (1999). Diurnal and ultradian rhythms of behaviour in a mare group of Przewalski horse (Equus ferus przewalskii), measured through one year under semi-reserve conditions. Appl. Anim. Behav. Sci., 64(1), 1–17.
Abstract: Investigations were conducted on four horses from a group of 12 Przewalski mares raised in different zoos and kept in a 44-ha enclosure under semi-natural conditions. Activity and feeding were continuously measured every second and were saved every 15 min by the storage-telemetry system ETHOSYS, from June 1995 to July 1996. Body mass of the horses was regularly recorded. Daily and monthly mean values, power spectra and DFC (as a measure for stability of rhythms synchronised with circadiurnal period) for activity and feeding were calculated. The general pattern of activity and feeding over the year was closely related to sunrise and sunset. Feeding accounted for 40% of total activity in summer and 62% in spring (all-year average being 52%). The level of activity was lowest in winter; whereas feeding was lowest in summer. The time budget for feeding reflected both feeding conditions and the annual pattern of body condition. Greatest activity occurred during daylight hours. Only on hot summer days, activity at night was higher than during daylight hours. Spectral analysis of activity and feeding in Przewalski horse showed a time pattern which was characterised by 24-h rhythmicity, but also by ultradian components with period lengths between 4.8 and 12 h, i.e., an activity pattern of up to five strong bouts per day. Annual variation in the pattern of power spectra was not high during the year. Results are discussed in connection with horse feeding strategy. Analysing the time structure of long-term and continuously measured activity and feeding could be a useful method to follow the general living conditions, especially the nutritional situation and to detect stressful conditions.
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Stahl, F., & Dorner, G. (1982). Responses of salivary cortisol levels to stress-situations. Endokrinologie, 80(2), 158–162.
Abstract: A procedure is described for determining salivary cortisol levels by a competitive protein-binding assay using horse transcortin. The collection of saliva was performed by means of filter paper-strips. Filter paper samples are more than 5 days stable after air-drying. In this form, the samples could be stored without refrigerator or deep-freezer and, if necessary, sent by post to the laboratory without any special precaution. Stressful situation of either painful or anxious origin were associated with an adequate increase of salivary cortisol levels. The increases were 157 to 230% of the initial or normal values dependent on the kind of stress. The mean values in 4 cases of Cushing's syndrome were 380% and 1 hour after 25 I.U. ACTH 690% higher than those in normal persons. In normal persons, a well-defined circadian rhythm has been observed.
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Bottoms, G. D., Roesel, O. F., Rausch, F. D., & Akins, E. L. (1972). Circadian variation in plasma cortisol and corticosterone in pigs and mares. Am J Vet Res, 33(4), 785–790. |
Oliveira-Santos, L. G. R., Machado-Filho, L. C. P., Tortato, M. A., & Brusius, L. (2010). Influence of extrinsic variables on activity and habitat selection of lowland tapirs (Tapirus terrestris) in the coastal sand plain shrub, southern Brazil. Mammalian Biology – Zeitschrift für Säugetierkunde, 75(3), 219–226.
Abstract: The objectives of this research were to: 1. evaluate the circadian activity patterns of lowland tapirs (Tapirus terrestris) throughout the seasons and 2. study the influence of moonlight, temperature and rainfall on the activity patterns and habitat selection of this species, in the coastal sand shrub in southern Brazil. From June 2005 to June 2006, eight tapirs were monitored in a large enclosure containing open and vegetation-covered areas, using four camera traps. Differences in activity patterns within seasons were found. Tapir predominately presented nocturnal-crepuscular activity; however, they differed in the winter, with cathemeral activity patterns. Covered areas were mostly used during periods of extreme temperatures, with less diurnal and more nocturnal activities within these areas, on hotter days. Activity in open areas mainly occurred during periods of intermediate temperatures, both during the day and in the night. Moonlight intensity did not influence nocturnal activities. On days of precipitation of 34 mm or more, there was no record of open-area activities, despite constant activity in covered-area.
Keywords: Behaviour; Circadian rhythmic; Moonlight; Rainfall; Temperature
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Touma, C., Sachser, N., Mostl, E., & Palme, R. (2003). Effects of sex and time of day on metabolism and excretion of corticosterone in urine and feces of mice. Gen Comp Endocrinol, 130(3), 267–278.
Abstract: Non-invasive techniques to monitor stress hormones in small animals like mice offer several advantages and are highly demanded in laboratory as well as in field research. Since knowledge about the species-specific metabolism and excretion of glucocorticoids is essential to develop such a technique, we conducted radiometabolism studies in mice (Mus musculus f. domesticus, strain C57BL/6J). Each mouse was injected intraperitoneally with 740 kBq of 3H-labelled corticosterone and all voided urine and fecal samples were collected for five days. In a first experiment 16 animals (eight of each sex) received the injection at 9 a.m., while eight mice (four of each sex) were injected at 9 p.m. in a second experiment. In both experiments radioactive metabolites were recovered predominantly in the feces, although males excreted significantly higher proportions via the feces (about 73%) than females (about 53%). Peak radioactivity in the urine was detected within about 2h after injection, while in the feces peak concentrations were observed later (depending on the time of injection: about 10h postinjection in experiment 1 and about 4h postinjection in experiment 2, thus proving an effect of the time of day). The number and relative abundance of fecal [3H]corticosterone metabolites was determined by high performance liquid chromatography (HPLC). The HPLC separations revealed that corticosterone was extensively metabolized mainly to more polar substances. Regarding the types of metabolites formed, significant differences were found between males and females, but not between the experiments. Additionally, the immunoreactivity of these metabolites was assessed by screening the HPLC fractions with four enzyme immunoassays (EIA). However, only a newly established EIA for 5alpha-pregnane-3beta,11beta,21-triol-20-one (measuring corticosterone metabolites with a 5alpha-3beta,11beta-diol structure) detected several peaks of radioactive metabolites with high intensity in both sexes, while the other EIAs showed only minor immunoreactivity. Thus, our study for the first time provides substantial information about metabolism and excretion of corticosterone in urine and feces of mice and is the first demonstrating a significant impact of the animals' sex and the time of day. Based on these data it should be possible to monitor adrenocortical activity non-invasively in this species by measuring fecal corticosterone metabolites with the newly developed EIA. Since mice are extensively used in research world-wide, this could open new perspectives in various fields from ecology to behavioral endocrinology.
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Touma, C., Palme, R., & Sachser, N. (2004). Analyzing corticosterone metabolites in fecal samples of mice: a noninvasive technique to monitor stress hormones. Horm Behav, 45(1), 10–22.
Abstract: In small animals like mice, the monitoring of endocrine functions over time is constrained seriously by the adverse effects of blood sampling. Therefore, noninvasive techniques to monitor, for example, stress hormones in these animals are highly demanded in laboratory as well as in field research. The aim of our study was to evaluate the biological relevance of a recently developed technique to monitor stress hormone metabolites in fecal samples of laboratory mice. In total, six experiments were performed using six male and six female mice each. Two adrenocorticotropic hormone (ACTH) challenge tests, two dexamethasone (Dex) suppression tests and two control experiments [investigating effects of the injection procedure itself and the diurnal variation (DV) of glucocorticoids (GCs), respectively] were conducted. The experiments clearly demonstrated that pharmacological stimulation and suppression of adrenocortical activity was reflected accurately by means of corticosterone metabolite (CM) measurements in the feces of males and females. Furthermore, the technique proved sensitive enough to detect dosage-dependent effects of the ACTH/Dex treatment and facilitated to reveal profound effects of the injection procedure itself. Even the naturally occurring DV of GCs could be monitored reliably. Thus, our results confirm that measurement of fecal CM with the recently established 5alpha-pregnane-3beta,11beta,21-triol-20-one enzyme immunoassay is a very powerful tool to monitor adrenocortical activity in laboratory mice. Since mice represent the vast majority of all rodents used for research worldwide and the number of transgenic and knockout mice utilized as animal models is still increasing, this noninvasive technique can open new perspectives in biomedical and behavioral science.
Keywords: Adrenal Cortex/drug effects; Adrenal Cortex Function Tests; Adrenocorticotropic Hormone/pharmacology; Analysis of Variance; Animals; Circadian Rhythm; Corticosterone/*analysis/metabolism; Dexamethasone/pharmacology; Feces/*chemistry; Female; Immunoenzyme Techniques/*methods; Male; Mice; Mice, Inbred C57BL; Models, Animal; Reproducibility of Results; Stress, Psychological/*metabolism
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Keay, J. M., Singh, J., Gaunt, M. C., & Kaur, T. (2006). Fecal glucocorticoids and their metabolites as indicators of stress in various mammalian species: a literature review. J Zoo Wildl Med, 37(3), 234–244.
Abstract: Conservation medicine is a discipline in which researchers and conservationists study and respond to the dynamic interplay between animals, humans, and the environment. From a wildlife perspective, animal species are encountering stressors from numerous sources. With the rapidly increasing human population, a corresponding increased demand for food, fuel, and shelter; habitat destruction; and increased competition for natural resources, the health and well-being of wild animal populations is increasingly at risk of disease and endangerment. Scientific data are needed to measure the impact that human encroachment is having on wildlife. Nonbiased biometric data provide a means to measure the amount of stress being imposed on animals from humans, the environment, and other animals. The stress response in animals functions via glucocorticoid metabolism and is regulated by the hypothalamic-pituitary-adrenal axis. Fecal glucocorticoids, in particular, may be an extremely useful biometric test, since sample collection is noninvasive to subjects and, therefore, does not introduce other variables that may alter assay results. For this reason, many researchers and conservationists have begun to use fecal glucocorticoids as a means to measure stress in various animal species. This review article summarizes the literature on many studies in which fecal glucocorticoids and their metabolites have been used to assess stress levels in various mammalian species. Variations between studies are the main focus of this review. Collection methods, storage conditions, shipping procedures, and laboratory techniques utilized by different researchers are discussed.
Keywords: Animals; *Animals, Wild/metabolism; Chromatography, High Pressure Liquid/methods/veterinary; Circadian Rhythm; Conservation of Natural Resources; *Ecosystem; Feces/*chemistry; Glucocorticoids/*analysis/metabolism; Humans; Seasons; Species Specificity; Specimen Handling/methods/veterinary; Stress, Psychological/*metabolism
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