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SUMMARY: As global poultry production expands to meet rising demand, the susceptibility of birds to heat stress has increased owing to advancements in chicken genetics and global warming. This review explores the significant impact of heat stress on poultry gut health by altered gut permeability and microbiota. Heat stress is characterised by prolonged exposure to elevated ambient temperatures, triggering thermoregulatory processes in poultry, which can lead to adverse effects such as respiratory alkalosis and bone degeneration. These physiological disruptions compromise homoeostasis, suppress intestinal immunity and digestive functions and cause gastrointestinal inflammation, thereby affecting the growth, productivity and overall well-being of poultry. Various strategies, including housing modifications, genetic selection, food manipulation and the use of feed additives, such as bioactive chemicals, prebiotics, organic acids, medicinal plants and probiotics, have been employed to mitigate these effects. This review emphasises the role of feed additives in supporting poultry gut health, thereby enhancing animal welfare, productivity and sustainability in the face of climate change. Future research avenues are suggested to improve our understanding and development of effective nutritional strategies to combat heat stress in poultry. [ABSTRACT FROM AUTHOR]

Introduction: Non-invasive hormone assessment is growing in interest as producers and livestock researchers seek new methods to assess animal welfare. Non-invasive wool assessment offers long-term, historic reflections of hormone concentration at the scale of weeks and months - and are not limited by sampling stress - thus making wool an appropriate tissue for long-term hormone analysis. This pilot study quantified cortisol and testosterone concentrations of ram fleece and determined if there is a significant difference between segments of the sample staple, and whether there is a correlation between hormones. Cortisol is a glucocorticoid produced within the adrenal glands and secreted in anticipation of or in response to a stressor. Testosterone is an androgen mainly synthesised within the testes of males and responsible for several critical functions including regulation of muscle growth, libido and spermatogenesis. Methods: In our study, 70 topknot wool samples were collected from rams on a commercial stud property in Dirranbandi, Queensland, Australia. Of these animals, 12 samples were selected at random to undergo cortisol and testosterone quantification. In the laboratory, a single, intact staple was isolated from the total sample, divided into 10 mm segments and prepared for their respective (cortisol or testosterone) immunoassays. Results: No significant difference (p > 0.05) was found between wool segments for either cortisol or testosterone, however, statistical differences (p < 0.05) were found between individuals for both hormones. A strong positive correlation (R2 = 0.9173, p < 0.05) was found between wool cortisol and testosterone concentrations. Discussion: In summary, this study reveals the major future possibilities for noninvasive wool hormone assessment in merino rams. [ABSTRACT FROM AUTHOR]

Koala (Phascolarctos cinereus) joey rescues are increasing over the past decade, and rehabilitation of a joey requires extensive care, and close proximity and handling by humans. These novel environments are likely to present a suite of biotic and abiotic stressors during rehabilitation. In this study, we aimed to monitor the physiological response of orphaned koala joeys to potential stressors. A total of 92 faecal samples were analysed for faecal cortisol metabolites (FCMs) using a polyclonal R4866 cortisol enzyme-immunoassay which has been previously validated in koalas. The iterative baseline method was used to establish FCM profiles of all individuals, and to identify significant peaks in FCM concentrations. Visitor events were identified and confirmed as an acute stressor based on the FCM profiles of the koala joeys. All koala joeys were found to have a significant rise in FCM concentrations after each visitor encounter. These results provide the first record of acute stress response of koala joeys to visitors. We suggest that visitor encounters be kept to a minimum and perhaps avoided altogether, especially for young rehabilitating joeys. [ABSTRACT FROM AUTHOR]

To deliver a comprehensive learning experience while shifting to online teaching due to COVID-19, educators at The University of Queensland (Australia) adopted Lt, a cloud-based platform, to overcome the challenges of delivering animal anatomy practicals. A two-phased study was conducted to evaluate the use of Lt for both online and on-campus students and its impact on student satisfaction and performance. Phase 1 investigated students' satisfaction with the practical experience, with online students expressing greater satisfaction across all constructs related to the practical: design, Lt, and feedback. Phase 2 investigated end-of-course evaluations, with all evaluated items increasing from 2019 to 2020 and 2021, along with student performance showing no difference between the online and on-campus students for practical assessment items and final examinations. The findings give confidence for technology adoption to enhance the learning experience for online students and provides an exemplar for similar adoption for practical delivery across other science disciplines. [ABSTRACT FROM AUTHOR]

Context. Wildlife rescue and rehabilitation centres aid millions of species worldwide. The clinical databases from these wildlife rehabilitation centres are increasingly being recognised as valuable scientific resources that have the potential to yield information on animal biology and inform conservation efforts. Although orphaned koala joeys constitute a substantial proportion of wildlife rescues in Australia, the causes of morbidity and mortality, specifically in rescued young koalas, remain largely unexplored. Aims. The primary aim of this study is to analyse the trends in causes and outcomes of koala joeys admitted for rehabilitation at the Adelaide Koala Wildlife Centre (AKWC). Methods. We analysed the hospital records of koala joeys admitted to the AKWC over an 8-year period (2014–2021) to identify the major causes of morbidity and mortality, and analysed the trends in arrivals in terms of season, sex and release rate. Key results. Our examination indicates that the top five major reasons for admission and mortality in koala joeys are as follows – renal disease, heat stress, chlamydiosis, animal attack and vehicle collision. A significant increase in the proportion of heat stress, renal disease and chlamydiosis cases can be observed over the study period. Of the major causes of mortality, the most distinctive feature is the exceptionally high mortality rate of koala joeys with renal disease. Over the study period, the overall positive outcome for all joeys increased up to two-fold, and the mortality rate also declined slightly. Conclusion. Despite the significant increase in positive outcome, it is evident that renal disease, chlamydiosis and heat stress are increasing at a rapid rate. Renal disease poses a major threat to rehabilitating koala joeys due to its severely high mortality rate. Implication. This is the first study identifying the key drivers of morbidity and mortality of rescued koala joeys, and the rapid increase of renal disease, chlamydiosis and heat stress warrant the attention of future conservation policy developers. Furthermore, the severely high mortality rate of koala joeys due to renal disease warrants improving treatment protocols and any measures that can help reduce the mortality rate of this disease in koala joeys. [ABSTRACT FROM AUTHOR]