פרסומים

Optimal embryonic development and growth of meat-type chickens (broilers) rely on incubation conditions (oxygen, heat, and humidity), on nutrients and on energy resources within the egg. Throughout incubation and according to the embryo’s energy balance, the main energy storage molecules (creatine and glycogen) are continuously utilized and synthesized, mainly in the embryonic liver, breast muscle, and the extraembryonic yolk sac (YS) tissue. During the last phase of incubation, as the embryo nears hatching, dynamic changes in energy metabolism occur. These changes may affect embryonic survival, hatchlings’ uniformity, quality and post hatch performance of broilers, hence, being of great importance to poultry production. Here, we followed the dynamics of creatine and glycogen from embryonic day (E) 11 until hatch and up to chick placement at the farm. We showed that creatine is stored mainly in the breast muscle while glycogen is stored mainly in the YS tissue. Analysis of creatine synthesis genes revealed their expression in the liver, kidney, YS tissue and in the breast muscle, suggesting a full synthesis capacity in these tissues. Expression analysis of genes involved in gluconeogenesis, glycogenesis, and glycogenolysis, revealed that glycogen metabolism is most active in the liver. Nevertheless, due to the relatively large size of the breast muscle and YS tissue, their contribution to glycogen metabolism in embryos is valuable. Towards hatch, post E19, creatine levels in all tissues increased while glycogen levels dramatically decreased and reached low levels at hatch and at chick placement. This proves the utmost importance of creatine in energy supply to late-term embryos and hatchlings.

While political communication scholarship has long underscored the importance of political talk—casual conversations about news and politics that occur in everyday situations—as a way for citizens to clarify their opinions and as a precursor for political engagement, much of this literature tends to depict political talk as uncomfortable and difficult for citizens. Yet, this focus on the challenging aspects of political talk has been informed predominantly by the US context. To what extent may a different picture emerge when looking across different cultural contexts? And how are these dynamics shaped by the affordances of the multi-platform social media environment? This paper explores these questions through a unique dataset of 122 qualitative interviews conducted between 2016 and 2019 with young people (ages 18–29) from five countries: Argentina, Finland, Israel, Japan, and the United States. Rather than solidifying the avoidance of controversial political talk as the key strategy at the disposal of young people, our findings point at a five-pronged typology of young people, with each type representing a different approach toward political talk. Our typology thus contributes to a more comprehensive and nuanced picture of various approaches towards political talk employed by young people across different countries and in relation to different digital media affordances.