Actions of glucocorticoids at a seasonal baseline as compared to stress-related levels in the regulation of periodic life processes

For decades, demands associated with the predictable life-history cycle have been considered stressful and have not been distinguished from stress that occurs in association with unpredictable and life-threatening perturbations in the environment. The recent emergence of the concept of allostasis distinguishes behavioral and physiological responses to predictable routines as opposed to unpredictable perturbations, and allows […]

Paradoxical sleep deprivation activates hypothalamic nuclei that regulate food intake and stress response

A large body of evidence has shown that prolonged paradoxical sleep deprivation (PSD) results in hypothalamic–pituitary–adrenal (HPA) axis activation, and in loss of body weight despite an apparent increase of food intake, reflecting increased energy expenditure. The flowerpot technique for PSD is an efficient paradigm for investigating the relationships among metabolic regulation and stress response. […]

Relationship between feeding time and food intake in hamadryas baboons (Papio hamadryas) and the value of feeding time as predictor of food intake

Abstract 10.1002/(SICI)1098-2361(1999)18:63.3.CO;2-L The relationship among time spent feeding, number of feeding bouts, feeding bout length, and the amount of food ingested was determined in a study of 18 hamadryas baboons (Papio hamadryas) at the German Primate Center (DPZ). There was considerable within- and between-subject variation in all four variables. Feeding time and number of feeding […]

Effect of dietary fiber concentration on apparent digestibility and digesta passage in non-human primates. I. Ruffed lemurs (Varecia variegata variegata and V. v. rubra)

Abstract 10.1002/(SICI)1098-2361(1999)18:63.3.CO;2-4 Two test diets with different fiber concentrations (15% acid detergent fiber [ADF], 30% ADF) were fed to five adult female ruffed lemurs (Varecia variegata). Apparent digestibility (%) of dry matter (DM), gross energy (GE), and fiber components (neutral detergent fiber [NDF], ADF, hemicellulose [HC], and cellulose [C]) were measured. Rates of digesta transit […]

Effect of dietary fiber concentration on apparent digestibility and digesta passage in non-human primates. II. Hindgut- and foregut-fermenting folivores

Abstract 10.1002/(SICI)1098-2361(1999)18:63.3.CO;2-6 Two test diets with different acid detergent fiber (ADF) concentrations (15% ADF, 30% ADF) were fed to seven adult hindgut- and seven adult foregut-fermenting primates. Apparent digestibilities (%) of dietary dry matter (DM), gross energy (GE), and fiber components (neutral detergent fiber [NDF], ADF, hemicellulose [HC], and cellulose [C]) were measured. Rates of […]

The effect of food quality and relative abundance on food choice in fallow deer

The diet choice of large herbivores is influenced by the presence of nutrients and toxins in available plants. It is generally assumed that herbivores ingest food that contains higher amounts of nutrients and lower amounts of toxins than the average of the food available. We studied the effects of quality and relative abundance on food […]

Diet choice, cortisol reactivity, and emotional feeding in socially housed rhesus monkeys

Chronic psychosocial stress produces an array of adverse health consequences that are highly comorbid, including emotional eating, affective disorders, and metabolic syndrome. The consumption of high caloric diets (HCDs) is thought to provide comfort in the face of unrelenting psychosocial stress. Using social subordination in female rhesus monkeys as a model of continual exposure to […]

Behavioral and physiological characterization of male mice under chronic psychosocial stress

Social stress is a major factor in the etiology of several psychopathologies, with individuals greatly differing in vulnerability. The development of appropriate animal models of social stress is, thus, a major challenge of modern bio-medical research. Adult male mice were subjected to a new model of chronic psychosocial stress in which resident/intruder dyads live chronically […]

Quantifying food intake in socially housed monkeys: Social status effects on caloric consumption

Obesity results from a number of factors including socio-environmental influences and rodent models show that several different stressors increase the preference for calorically dense foods leading to an obese phenotype. We present here a non-human primate model using socially housed adult female macaques living in long-term stable groups given access to diets of different caloric […]

Appetite regulation: The central role of melatonin in Danio rerio

Melatonin is the hormonal mediator of photoperiodic information to the central nervous system in vertebrates and allows the regulation of energy homeostasis through the establishment of a proper balance between energy intake and energy expenditure. The aim of this study was to evaluate the role of melatonin in appetite central control analyzing the involvement of […]