Ectoparasites of medical and veterinary importance: Drug resistance and the need for alternative control methods

Objectives: Despite multiple attempts at eradication, many ectoparasites of humans and domestic livestock remain a persistent problem in the modern world. For many years, a range of pesticide drugs including organophosphates, organochlorides and synthetic pyrethroids provided effective control of these parasites; but intensive use of these drugs has led to the evolution of resistance in many target species. This paper aims to review the effectiveness of current control methods and discuss potential alternatives for the long term sustainable control of ectoparasites. Key Findings: Important medical ectoparasites such as scabies mites, head lice and bed bugs present a significant public health problem, and so adequate control methods are essential. Ectoparasites of domestic livestock and farmed fish (for example sheep scab mites, poultry mites and sea lice) are also of concern given the increasing strain on the world's food supply. These parasites have become resistant to several classes of pesticide, making control very difficult. Recently, an increasing amount of research has focussed on alternative control methods such as insect growth regulators, biological control using essential oils or fungi, as well as vaccine development against some ectoparasites of medical and veterinary importance. Summary: Drug resistance is prevalent in all of the ectoparasites discussed in this review. A wide variety of alternative control methods have been identified, however further research is necessary in order for these to be used to successfully control ectoparasitic diseases in the future

Early stage litter decomposition across biomes

[Departement_IRSTEA]Territoires [TR1_IRSTEA]SEDYVINInternational audienceThrough litter decomposition enormous amounts of carbon is emitted to the atmosphere. Numerous large-scale decomposition experiments have been conducted focusing on this fundamental soil process in order to understand the controls on the terrestrial carbon transfer to the atmosphere. However, previous studies were mostly based on site-specific litter and methodologies, adding major uncertainty to syntheses, comparisons and meta-analyses across different experiments and sites. In the TeaComposition initiative, the potential litter decomposition is investigated by using standardized substrates (Rooibos and Green tea) for comparison of litter mass loss at 336 sites (ranging fro

Effects of climate and atmospheric nitrogen deposition on early to mid-term stage litter decomposition across biomes

International audienceLitter decomposition is a key process for carbon and nutrient cycling in terrestrial ecosystems and is mainly controlled by environmental conditions, substrate quantity and quality as well as microbial community abundance and composition. In particular, the effects of climate and atmospheric nitrogen (N) deposition on litter decomposition and its temporal dynamics are of significant importance, since their effects might change over the course of the decomposition process. Within the TeaComposition initiative, we incubated Green and Rooibos teas at 524 sites across nine biomes. We assessed how macroclimate and atmospheric inorganic N deposition under current and predicted scenarios (RCP 2.6, RCP 8.5) might affect litter mass loss measured after 3 and 12 months. Our study shows that the early to mid-term mass loss at the global scale was affected predominantly by litter quality (explaining 73% and 62% of the total variance after 3 and 12 months, respectively) followed by climate and N deposition. The effects of climate were not litter-specific and became increasingly significant as decomposition progressed, with MAP explaining 2% and MAT 4% of the variation after 12 months of incubation. The effect of N deposition was litter-specific, and significant only for 12-month decomposition of Rooibos tea at the global scale. However, in the temperate biome where atmospheric N deposition rates are relatively high, the 12-month mass loss of Green and Rooibos teas decreased significantly with increasing N deposition, explaining 9.5% and 1.1% of the variance, respectively. The expected changes in macroclimate and N deposition at the global scale by the end of this century are estimated to increase the 12-month mass loss of easily decomposable litter by 1.1– 3.5% and of the more stable substrates by 3.8–10.6%, relative to current mass loss. In contrast, expected changes in atmospheric N deposition will decrease the mid-term mass loss of high-quality litter by 1.4–2.2% and that of low-quality litter by 0.9–1.5% in the temperate biome. Our results suggest that projected increases in N deposition may have the capacity to dampen the climate-driven increases in litter decomposition depending on the biome and decomposition stage of substrate

Early stage litter decomposition across biomes

Through litter decomposition enormous amounts of carbon is emitted to the atmosphere. Numerous large-scale decomposition experiments have been conducted focusing on this fundamental soil process in order to understand the controls on the terrestrial carbon transfer to the atmosphere. However, previous studies were mostly based on site-specific litter and methodologies, adding major uncertainty to syntheses, comparisons and meta-analyses across different experiments and sites. In the TeaComposition initiative, the potential litter decomposition is investigated by using standardized substrates (Rooibos and Green tea) for comparison of litter mass loss at 336 sites (ranging from −9 to +26 °C MAT and from 60 to 3113 mm MAP) across different ecosystems. In this study we tested the effect of climate (temperature and moisture), litter type and land-use on early stage decomposition (3 months) across nine biomes. We show that litter quality was the predominant controlling factor in early stage litter decomposition, which explained about 65% of the variability in litter decomposition at a global scale. The effect of climate, on the other hand, was not litter specific and explained <0.5% of the variation for Green tea and 5% for Rooibos tea, and was of significance only under unfavorable decomposition conditions (i.e. xeric versus mesic environments). When the data were aggregated at the biome scale, climate played a significant role on decomposition of both litter types (explaining 64% of the variation for Green tea and 72% for Rooibos tea). No significant effect of land-use on early stage litter decomposition was noted within the temperate biome. Our results indicate that multiple drivers are affecting early stage litter mass loss with litter quality being dominant. In order to be able to quantify the relative importance of the different drivers over time, long-term studies combined with experimental trials are needed.This work was performed within the TeaComposition initiative, carried out by 190 institutions worldwide. We thank Gabrielle Drozdowski for her help with the packaging and shipping of tea, Zora Wessely and Johannes Spiegel for the creative implementation of the acknowledgement card, Josip Dusper for creative implementation of the graphical abstract, Christine Brendle for the GIS editing, and Marianne Debue for her help with the data cleaning. Further acknowledgements go to Adriana Principe, Melanie Köbel, Pedro Pinho, Thomas Parker, Steve Unger, Jon Gewirtzman and Margot McKleeven for the implementation of the study at their respective sites. We are very grateful to UNILEVER for sponsoring the Lipton tea bags and to the COST action ClimMani for scientific discussions, adoption and support to the idea of TeaComposition as a common metric. The initiative was supported by the following grants: ILTER Initiative Grant, ClimMani Short-Term Scientific Missions Grant (COST action ES1308; COST-STSM-ES1308-36004; COST-STM-ES1308-39006; ES1308-231015-068365), INTERACT (EU H2020 Grant No. 730938), and Austrian Environment Agency (UBA). Franz Zehetner acknowledges the support granted by the Prometeo Project of Ecuador's Secretariat of Higher Education, Science, Technology and Innovation (SENESCYT) as well as Charles Darwin Foundation for the Galapagos Islands (2190). Ana I. Sousa, Ana I. Lillebø and Marta Lopes thanks for the financial support to CESAM (UID/AMB/50017), to FCT/MEC through national funds (PIDDAC), and the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020. The research was also funded by the Portuguese Foundation for Science and Technology, FCT, through SFRH/BPD/107823/2015 (A.I. Sousa), co-funded by POPH/FSE. Thomas Mozdzer thanks US National Science Foundation NSF DEB-1557009. Helena C. Serrano thanks Fundação para a Ciência e Tecnologia (UID/BIA/00329/2013). Milan Barna acknowledges Scientific Grant Agency VEGA (2/0101/18). Anzar A Khuroo acknowledges financial support under HIMADRI project from SAC-ISRO, India

Early stage litter decomposition across biomes

peer reviewedThrough litter decomposition enormous amounts of carbon is emitted to the atmosphere. Numerous large-scale decomposition experiments have been conducted focusing on this fundamental soil process in order to understand the controls on the terrestrial carbon transfer to the atmosphere. However, previous studies were mostly based on site-specific litter and methodologies, adding major uncertainty to syntheses, comparisons and metaanalyses across different experiments and sites. In the TeaComposition initiative, the potential litter decomposition is investigated by using standardized substrates (Rooibos and Green tea) for comparison of litter mass loss at 336 sites (ranging from −9 to +26 °C MAT and from 60 to 3113mm MAP) across different ecosystems. In this study we tested the effect of climate (temperature and moisture), litter type and land-use on early stage decomposition (3 months) across nine biomes. We show that litter quality was the predominant controlling factor in early stage litter decomposition, which explained about 65% of the variability in litter decomposition at a global scale. The effect of climate, on the other hand, was not litter specific and explained b0.5% of the variation for Green tea and 5% for Rooibos tea, and was of significance only under unfavorable decomposition conditions (i.e. xeric versus mesic environments).When the data were aggregated at the biome scale, climate played a significant role on decomposition of both litter types (explaining 64% of the variation for Green tea and 72% for Rooibos tea).No significant effect of land-use on early stage litter decompositionwas notedwithin the temperate biome. Our results indicate that multiple drivers are affecting early stage littermass loss with litter quality being dominant. In order to be able to quantify the relative importance of the different drivers over time, long-term studies combined with experimental trials are needed