999 resultados para breeding diet
Resumo:
1.Sex allocation theory has received considerable attention, yet the mechanism(s) by which mothers skew offspring sex ratios remain unknown. In birds, females are the heterogametic sex, which potentially gives them control of whether gametes will be male or female. How females might control the sex of the gamete is unclear, but one possibility is that variation in steroid hormones may mediate this process. 2.We experimentally altered circulating levels of corticosterone in female Gouldian finches (Erythrura gouldiae), a species that demonstrates both extreme stress responses and extreme offspring sex ratio biases when breeding with a low-quality (genetically incompatible) partner. 3.During egg production, individual females received both corticosterone and metyrapone (a corticosterone-synthesis inhibitor) implants, in random order, to induce both high and low levels of circulating stress hormones (within physiological limits). 4.We found that females with elevated corticosterone levels produced male-biased sex ratios, but when the same females were treated with metyrapone they produced female-biased offspring sex ratios. 5.These stress responses are adaptive because females constrained to breeding with low-quality males can substantially increase their fitness by overproducing sons. Changes in maternal corticosterone levels during stressful situations, such as the quality of a breeding partner, may provide an endocrine mechanism that can be exploited for strategic sex allocation.
Resumo:
Tanya investigated individual quality of Australasian gannets specifically breeding success, foraging behaviour, and diet. Tanya’s thesis presented previously unreported findings of how quality manifests itself among seabirds, and, demonstrated the importance of accounting for individual variation when examining parameters of reproductive success, particularly in relation to long-term ecological processes.
Resumo:
Aim:
Background:
Diabetes education has become a priority area in primary and secondary care, and many education programmes are now embedded within a patient’s care package. There are few contemporaneous explorations of patients’ views about lifestyle self-management. Such research is vital in order to identify areas that require further support, refinement or enhancement in terms of patient education.
Methods:
Focus groups were held with patients recently diagnosed with type 2 diabetes (n516, 38% female, aged 45–73 years). In-depth semi-structured interviews were conducted with HPs (n57). Discussions focussed on self-management specifically in relation to making dietary and physical activity changes. All discussions were tape recorded, transcribed and analysed by emergent themes analysis using NVivo to manage the coded data.
Findings:
Barriers were divided into six main categories: difficulty changing well- stablished habits, negative perception of the ‘new’ or recommended regimen, barriers relating to social circumstances, lack of knowledge and understanding, lack of motivation and barriers relating to the practicalities of making lifestyle changes. HPs generally echoed the views of patients. In conclusion, even against a background of diabetes education, recently diagnosed patients with type 2 diabetes discussed a wide range of barriers to self-management of diet and physical activity. The findings could help to provide HPs with a deeper understanding of the needs of recently diagnosed patients and may help refine current diabetes education activities and inform the development of educational resources.
Resumo:
Class II and III obesity (BMI >35 kg·m2) have increased dramatically in recent years. Current clinical guidelines suggest diet and exercise as first line treatment for adults throughout the spectrum of overweight and obesity. However, to date there is no systematic review that examines the effects of diet and exercise on this high risk population. This systematic review will examine the combined effects of diet versus diet and exercise on body composition in severe obesity. Medline and Cinahl were searched for randomised controlled trials comparing diet and exercise to diet alone. Studies published until July 2013 were included if they used reliable methods for analysing body composition in adults with BMI ≥ 35 kg·m2. Five of 459 studies met the inclusion criteria. Two studies, both in older adults, reported that exercise reduced lean mass loss during weight loss. Two studies showed that exercise facilitated (greater) fat mass loss. The remaining study reported no differences in body composition when exercise is added to energy restriction. Exercise training during energy restriction for individuals with BMI ≥35 kg.m2 may influence body composition outcomes but the evidence is limited. Further studies should focus on the efficacy of different exercise protocols during energy restriction for this population in order to better inform decision making for the treatment of severe obesity in respect to favourable body composition outcomes.
Resumo:
Peregrine Falcon’s lifetime reproductive outputs are influenced more by the quality of the nest site than by the environmental landscape in which they live. The installation of a nest boxes significantly improves breeding outcomes. Uniquely, Victorian Peregrines use novel (non-cliff) nest sites and disperse considerably shorter distances to adopt these sites.
