University of Adelaide

About: University of Adelaide is a education organization based out in Adelaide, South Australia, Australia. It is known for research contribution in the topics: Population & Poison control. The organization has 27251 authors who have published 79167 publications receiving 2671128 citations. The organization is also known as: The University of Adelaide & Adelaide University.

Microbiota of the chicken gastrointestinal tract: influence on health, productivity and disease.

Abstract: Recent advances in the technology available for culture-independent methods for identification and enumeration of environmental bacteria have invigorated interest in the study of the role of chicken intestinal microbiota in health and productivity. Chickens harbour unique and diverse bacterial communities that include human and animal pathogens. Increasing public concern about the use of antibiotics in the poultry industry has influenced the ways in which poultry producers are working towards improving birds' intestinal health. Effective means of antibiotic-independent pathogen control through competitive exclusion and promotion of good protective microbiota are being actively investigated. With the realisation that just about any change in environment influences the highly responsive microbial communities and with the abandonment of the notion that we can isolate and investigate a single species of interest outside of the community, came a flood of studies that have attempted to profile the intestinal microbiota of chickens under numerous conditions. This review aims to address the main issues in investigating chicken microbiota and to summarise the data acquired to date.

Social media engagement behaviour: a uses and gratifications perspective

Abstract: The proliferation of social media platforms and corresponding consumer adoption in recent years has precipitated a paradigm shift, significantly altering the ways customers engage with brands. Organisations recognise the social and network value of engagement within social media, and practitioners are endeavouring to build engagement through their social media content. However, theoretically based academic guidance concerning marketing practice and engagement in new media social networks is limited. This article provides a theoretical model to explicate the role of social media content in facilitating engagement behaviour within a social media context. Based on uses and gratifications theory, it provides a model for how an organisation can stimulate positively valenced engagement behaviour through social media and dissuade negatively valenced engagement behaviour in this forum. A typology of social media engagement behaviour is proposed and a series of hypotheses exploring the relationships between social...

A guide to Phanerozoic cold polar climates from high-latitude ice-rafting in the Cretaceous

Abstract: The high-latitude extent of warm-climate indicators at certain times in Earth history has been considered as evidence that the globe was ice-free for long intervals, despite theoretical considerations and results from numerical modelling experiments1,2 indicating that this was unlikely. One of the warmest periods, the Cretaceous, displays faunal and floral evidence for 'cool-temperate' to 'sub-tropical' conditions very near to the poles. However, our studies of Lower Cretaceous mudstones of central Australia that contain outsized exotic blocks have led to the conclusion that the blocks were emplaced by ice-rafting, implying that high-latitude ice was present at sea level. Strata of a similar origin of mid-Jurassic to mid-Cretaceous age occur on other continents that were positioned between 65° and 78° palaeolatitude. Indeed, there is a record of high-latitude ice-rafting throughout the Phanerozoic, suggesting that ice was present on Earth for much of its history, and that ice-free conditions could have been at most only episodic over the past 600 Myr.

Seminal plasma and male factor signalling in the female reproductive tract

Abstract: In mammals, insemination results in the transmission of seminal factors that act, in the female reproductive tract, to promote sperm survival, to “condition” the female immune response to tolerate the conceptus and to organise molecular and cellular changes in the endometrium to facilitate embryo development and implantation. These events are initiated when signalling agents, including transforming growth factor-β and other cytokines and prostaglandins secreted by seminal vesicle and prostate glands, interact with epithelial cells in the cervix and uterus to activate cytokine synthesis and to induce cellular and molecular changes resembling a classical inflammatory cascade. The consequences are the recruitment and activation of macrophages, granulocytes and dendritic cells, which have immune-regulatory and tissue-remodelling roles that culminate in improved endometrial receptivity to the implanting embryo. Cytokines elicited by seminal activation have embryotrophic properties and also contribute directly to the optimal development of the early embryo. This review summarises our current understanding of the physiology of responses to seminal plasma in the female reproductive tract and considers the evolutionary significance of seminal plasma in influencing female tissues to promote the success of pregnancy.

Effect of season and temperature on mortality in amphibians due to chytridiomycosis

Abstract: Objective To investigate the distribution and incidence of chytridiomycosis in eastern Australian frogs and to examine the effects of temperature on this disease. Design A pathological survey and a transmission experiment were conducted. Procedure Diagnostic pathology examinations were performed on free-living and captive, ill and dead amphibians collected opportunistically from eastern Australia between October 1993 and December 2000. We conducted a transmission experiment in the laboratory to investigate the effects of temperature: eight great barred frogs (Mixophyes fasciolatus) exposed to zoospores of Batrachochytrium dendrobatidis and six unexposed frogs were housed individually in each of three rooms held at 17°C, 23°C and 27°C. Results Chytridiomycosis was the cause of death or morbidity for 133 (55.2%) of 241 free-living amphibians and for 66 (58.4%) of 113 captive amphibians. This disease occurred in 34 amphibian species, was widespread around the eastern seaboard of Australia and affected amphibians in a variety of habitats at high and low altitudes on or between the Great Dividing Range and the coast. The incidence of chytridiomycosis was higher in winter, with 53% of wild frogs from Queensland and New South Wales dying in July and August. Other diseases were much less common and were detected mostly in spring and summer. In experimental infections, lower temperatures enhanced the pathogenicity of B dendrobatidis in M fasciolatus. All 16 frogs exposed to B dendrobatidis at 17°C and 23°C died, whereas 4 of 8 frogs exposed at 27°C survived. However, the time until death for the frogs that died at 27°C was shorter than at the lower temperatures. Infections in survivors were eliminated by 98 days. Conclusion Chytridiomycosis is a major cause of mortality in free-living and captive amphibians in Australia and mortality rate increases at lower temperatures.