Seasonal effects on reconciliation in Macaca Fuscata Yakui

Dietary composition may have profound effects on the activity budgets, levelof food competition, and social behavior of a species. Similarly, in seasonally breeding species, the mating season is a period in which competition for mating partners increases, affecting amicable social interactions among group members. We analyzed the importance of the mating season and of seasonal variations in dietary composition and food competition on econciliation in wild female Japanese macaques (Macaca fuscata yakui) on Yakushima Island, Japan. Yakushima macaques are appropriate subjects because they are seasonal breeders and their dietary composition significantly changes among the seasons. Though large differences occurred between the summer months and the winter and early spring months in activity budgets and the consumption of the main food sources, i.e., fruits, seeds, and leaves, the level of food competition and conciliatory tendency remained unaffected. Conversely,conciliatory tendency is significantly lower during the mating season than in the nonmating season. Moreover, conciliatory tendency is lower when 1 or both female opponents is in estrous than when they are not. Thus the mating season has profound effects on reconciliation, whereas seasonal changes in activity budgets and dietary composition do not. The detrimental effects of the mating season on female social relationships and reconciliation may be due to the importance of female competition for access to male partners in multimale, multifemale societies

Molecular psychiatry of zebrafish

Due to their well-characterized neural development and high genetic homology to mammals, zebrafish (Danio rerio) have emerged as a powerful model organism in the field of biological psychiatry. Here, we discuss the molecular psychiatry of zebrafish, and its implications for translational neuroscience research and modeling central nervous system (CNS) disorders. In particular, we outline recent genetic and technological developments allowing for in vivo examinations, high-throughput screening and whole-brain analyses in larval and adult zebrafish. We also summarize the application of these molecular techniques to the understanding of neuropsychiatric disease, outlining the potential of zebrafish for modeling complex brain disorders, including attention-deficit/hyperactivity disorder (ADHD), aggression, post-traumatic stress and substance abuse. Critically evaluating the advantages and limitations of larval and adult fish tests, we suggest that zebrafish models become a rapidly emerging new field in modern molecular psychiatry research

The relationships between feeding-group size and feeding rate vary from positive to negative with characteristics of food items in wild Japanese macaques (Macaca fuscata)

To understand the costs and benefits of group-living, it is important to clarify the impacts of other individuals on foraging success. Previous studies on group-living primates have focused on the relationship between feeding-group size and feeding rate in food patches, and have exhibited inconsistent results, showing positive, neutral, or negative relationships. The relationship realized will depend on the balance of positive and negative impacts of co-feeding on feeding rate. The intensity of negative impacts (i.e., feeding competition) may vary with some characteristics of food items such as (1) patch size, (2) within-patch food density, (3) within-patch distribution pattern of food, (4) the abundance and (5) distribution pattern of within-habitat food trees, and (6) the relative energy content among available food items. Thus, the balance of positive and negative impacts of co-feeding, and ultimately the relationship between feeding-group size and feeding rate, is expected to change with characteristics of food items. In this study of wild Japanese macaques (Macaca fuscata), the relationship between feeding-group size and feeding rate, and the above six characteristics of 12 main food items were assessed over six seasons. Positive, neutral, or negative relationships between feeding-group size and feeding rate were detected among these food items. Positive relationships were consistently associated with within-patch food density; higher food density within food patches was likely to lead to positive relationships. Thus, various relationships between feeding-group size and feeding rate should be attributed to these specific characteristics of food items, which alter the degree of feeding competition

Plant constituents affecting food selection by sika deer

We directly observed the feeding behaviors of Yaku sika deer (Cervus nippon yakushimae), the smallest subspecies of Japanese sika deer, by following 6 wild, habituated, and individually identifiable animals in a natural warm-temperate forest on the island of Yakushima, southern Japan, 2005-2006. Deer fed on various plant species and parts but predominantly on the fallen leaves, fruits, seeds, and flowers of woody plants (similar to 82% of food items) at 59 natural feeding plots. We analyzed 8 key plant constituents of eaten and uneaten items at the feeding plots, and examined the effects of each constituent on food selection by multivariate and univariate generalized linear mixed models. The multivariate analysis, which evaluated the effect of each plant constituent on food selection by controlling influences of the other constituents in the food items, showed that deer selected food items with higher contents of crude fat, crude protein, and total phenolics but with lower contents of lignin and condensed tannin from the available items at the feeding plots. Neither soluble nor structural carbohydrate, nor ash content affected selection of food items. It may be advantageous for these small ungulates with shorter gastrointestinal tracts to select foods that are relatively rich in fat because of the higher energy content of fat compared with carbohydrates. Furthermore, it appears that non-tannin phenolics may have beneficial functions in this species. The univariate analyses showed different effects of crude protein and structural carbohydrate on food selection compared to those derived from the multivariate analysis. We demonstrate that accounting for influences of other plant constituents by using multivariate analyses is important to ensure that any effects of individual plant constituents are not overlooked or overstated. (c) 2018 The Wildlife Society