Feeding Behavior of Sheep in Relation to Kinetics of Sagebrush Monoterpenes: Implications for Landscape Biodiversity

The sagebrush steppe is one of the most extensive vegetation types in the western US and an important habitat for wild and domestic herbivores. When sagebrush dominates, however, forage and habitat quality decline. Although sagebrush is nutritious, its forage value is reduced by terpenes. A better understanding of how terpenes limit intake is vital for increasing consumption of sagebrush and for enhancing and maintaining biodiversity in the sagebrush-steppe. To better understand how terpenes in sagebrush limit intake, we studied feeding behavior of sheep in the field, influence of sagebrush monoterpenes on regulation of intake in pens, and the feeding behavior of lambs in relation to the kinetics of camphor, 1,8-cineole, and p-cymene dosed intravenously and intraruminally. In field studies, supplemented ewes utilized more sagebrush than unsupplemented ewes. In pen studies, food intake and dietary concentrations of monoterpenes were inversely related. Lambs regulated feeding bout frequencies to minimize the toxic effects of monoterpenes. We proposed four complementary hypotheses to account for physiological mechanisms by which monoterpenes influence feeding behavior: 1) monoterpenes disturb acid-base balance, 2) monoterpenes cause satiation, 3) monoterpenes induce elimination pathways, and 4) rumen microbes adapt to monoterpenes. The first two addressed how monoterpenes limit intake and the last two addressed adaptation to monoterpenes. There was no induction of elimination pathways or disturbance of acid-base balance. Camphor, 1,8-cineole, and p-cymene dosed individually and in a cocktail affected feeding behavior and limited food intake by lambs. Feeding time did not change with repeated intravenous dosing with camphor, increased slightly with intravenous dosing with p-cymene and the terpene cocktail, but declined with intravenous dosing with 1,8-cineole. Lambs increased feeding time and food intake with repeated rumen dosing with camphor, 1,8-cineole, and the cocktail. Feeding time and food intake did not change with rumen dosing with p-cymene. Exposure to a terpene-containing diet led to rumen microbial adaptation, while kinetic rates remained unchanged. Satiation, elimination rates, and rumen microbe adaptation influence feeding time and food intake of lambs. Timing of grazing, supplements, stock density, and detoxification of sagebrush monoterpenes influence feeding behavior of sheep, with significant implications for biodiversity of sagebrush-grassland ecosystems

Career Management for Early Career Scientists in Developing Countries--A South African Experience

This paper discusses career development and options for growth for young scientists in developing countries. We also identify and address some of the common challenges early career scientists face, and apply key principles learned from years of research and experience in the South African context as a basis for our discussion. Early career scientists are more likely to succeed in their career if they understand from the start what they need to do in order to grow to the next level and ultimately to the pinnacle of their careers. Strategically, planning one’s individual career development is critical to success in the science environment as is the case in any other discipline or domain. The development of early career scientists through their career ladder is determined by a number of factors, many of which are within the control of early career scientists. These factors include qualifications, publication track record, attracting research funding, contribution to student training and staff development, leadership in science, and research impact. The contribution of this basket of measures to development of a career in science is critical for development to certain milestones in one’s career. One of the most critical transitions many research scientists have to make is the move from specialist to manager. Expedient promotion of early career scientists to senior management roles without an adequate track record, experience or proper training can be frustrating for both the manager and those under his/her management responsibility. Regardless of the career path one chooses, a solid foundation in research with a good track record of research outputs, funding and the impact of one’s research are crucial to one’s development along either the researcher career ladder or research management career path

The Effects of Seed Ingestion by Livestock, Dung Fertilization, Trampling, Grass Competition and Fire on Seedling Establishment of Two Woody Plant Species

The increasing rate of woody plant encroachment in grasslands or savannas remains a challenge to livestock farmers. The causes and control measures of woody plant encroachment are of common interest, especially where it negatively affects the objectives of an agricultural enterprise. The objectives of this study were to determine the effects of gut passage (goats, cattle), dung (nutrients), fire, grass competition and trampling on establishment of A. nilotica (Fabaceae) and D. cinerea (Fabaceae sub family Mimosoideae) seedlings. Germination trials were subjected to: 1) seed passage through the gut of cattle and goats and unpassed/ untreated seeds (i.e. not ingested), 2) dung and control (no dung), 3) grass and control (mowed grass), 4) fire and control (no fire), 5) trampling and control (no trampling)

Queer marginality and planning for brand resonance: A qualitative critique of the South African advertising industry

Meaning and purpose in brand advertising has gained prominence in society (Deloitte 2019. Millennial and Generation Z consumers in particular demand brands to have a clear position on social causes they care about. Consequently, the advertising industry is progressively recognising the importance of investing time and resources to gain an in-depth understanding of the prevailing political and sociocultural dynamics that affect targeted consumers in the social environments in which their brands exist. This enables brands to craft strategies that foster a strong cognitive and emotional connection within a diverse consumer base (Keller 2009; Badrinarayanan et al. 2016); and leverage these to craft meaningful advertisements that enhance brand resonance, brand equity, and social change (Enslin 2019; Minar 2016). The aim of this study was to examine the social constructions of gender and queer identity in advertising through the lens of brand communication planners; and to understand how the voices of the queer community are included in the planning and production of advertisements that resonate. Methodologically, a critical qualitative research approach was applied to investigate the experiences of the participants. Data were collected using semi-structured interviews. Queer theory and brand resonance theory were used to analyse and discuss the emerging themes

Response of land surface phenology to variation in tree cover during green-up and senescence periods in the semi-arid savannas in Southern Africa

Understanding the spatio-temporal dynamics of land surface phenology is important to understanding changes in landscape ecological processes of semi-arid savannas in Southern Africa. The aim of the study was to determine the influence of variation in tree cover percentage on land surface phenological response in the semi-arid savanna of Southern Africa. Various land surface phenological metrics for the green-up and senescing periods of the vegetation were retrieved from leaf index area (LAI) seasonal time series (2001 to 2015) maps for a study region in South Africa. Tree cover (%) data for 100 randomly selected polygons grouped into three tree cover classes, low (40%, n = 34), were used to determine the influence of varying tree cover (%) on the phenological metrics by means of the t-test. The differences in the means between tree cover classes were statistically significant (t-test p < 0.05) for the senescence period metrics but not for the green-up period metrics. The categorical data results were supported by regression results involving tree cover and the various phenological metrics, where tree cover (%) explained 40% of the variance in day of the year at end of growing season compared to 3% for the start of the growing season. An analysis of the impact of rainfall on the land surface phenological metrics showed that rainfall influences the green-up period metrics but not the senescence period metrics. Quantifying the contribution of tree cover to the day of the year at end of growing season could be important in the assessment of the spatial variability of a savanna ecological process such as the risk of fire spread with time.The Council for Industrial and Scientific Research (CSIR) Parliamentary Grant, Southern African Science Service Centre for Climate Change and Adaptive Land Management (SASSCAL) and ECOPOTENTIAL project which received funding from the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement No. 641762.http://www.mdpi.com/journal/remotesensingam2017Plant Production and Soil Scienc

‘Preventing the next pandemic’ – A 2020 UNEP Frontiers Series Report on zoonotic diseases with reflections for South Africa

Zoonoses account for about 25% of the infectious disease burden in low-income countries. Poverty might increase the risk for zoonotic disease where the active human–livestock and human–wildlife interfaces can increase the likelihood of disease transmission. A combined disease burden exists for people in areas such as tropical and subtropical Africa, where there is likelihood of co-infection with zoonotic diseases and other pathogenic or infectious diseases, such as malaria, tuberculosis and HIV.1 Many endemic zoonoses remain widely neglected in such settings, undetected and underreported, because their impacts are borne largely by impoverished and marginalised communities. Due to these unique contexts, the prevention and management of emerging and endemic zoonotic diseases in many African countries is a complex undertaking needing evidence-based guidance. In early 2020, the United Nations Environment Programme (UNEP) and the International Livestock Research Institute (ILRI) took on the urgent task to provide an up-to-date, rapid scientific assessment on zoonotic diseases as part of the UNEP’s Frontiers Report Series. The goal of the report is to provide relevant information for policymakers on how to ‘prevent the next pandemic’ by interrogating what is known about zoonotic diseases and how best one can break the chain of transmission. As the world presently faces the SARS-CoV-2 pandemic, this timely report helps decisionmakers with evidence-based actions, not only to flatten the curve of COVID-19 incidence, but to answer questions about zoonoses in general and plan for the future. In this Commentary, we give a brief overview of UNEP’s latest report and then relate some of the key messages and recommendations for policymakers to a South African context.http://www.sajs.co.zahj2020Geography, Geoinformatics and MeteorologyMammal Research InstituteZoology and Entomolog