Libration Point Mission Design Considerations

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The future of aquatic protein: implications for protein sources in aquaculture diets

Approximately 70% of the aquatic-based production of animals is fed aquaculture, whereby animals are provided with high-protein aquafeeds. Currently, aquafeeds are reliant on fish meal and fish oil sourced from wild-captured forage fish. However, increasing use of forage fish is unsustainable and, because an additional 37.4 million tons of aquafeeds will be required by 2025, alternative protein sources are needed. Beyond plantbased ingredients, fishery and aquaculture byproducts and insect meals have the greatest potential to supply the protein required by aquafeeds over the next 10–20 years. Food waste also has potential through the biotransformation and/or bioconversion of raw waste materials, whereas microbial and macroalgal biomass have limitations regarding their scalability and protein content, respectively. In this review, we describe the considerable scope for improved efficiency in fed aquaculture and discuss the development and optimization of alternative protein sources for aquafeeds to ensure a socially and environmentally sustainable future for the aquaculture industry

NASA Exploration Mission 2 Mission Design

Exploration Mission 2 (EM-2) will be NASAs first manned flight on the Space Launch System (SLS) and Orion Spacecraft. The mission has been changed from an SLS Block 1B configuration to Block 1. This change has necessitated a reexamination of the flight profile to determine what changes must be made in order to accommodate the reduced launch vehicle performance on the Block 1. Launch availability and orbital debris risk will be traded to find the best flight profile for both SLS and Orion

Molecular detection of six viral pathogens from Australian wild sourced giant black tiger shrimp (Penaeus monodon) broodstock

Disease presents a considerable challenge to the sustainability and development of global shrimp aquaculture. The Australian black tiger shrimp (Penaeus monodon) aquaculture industry is heavily reliant on wild-sourced broodstock for seedstock production, representing a large and under evaluated biosecurity risk. Currently, there is a paucity of quantitative, large-scale data detailing the extent of pathogenic agents in wild-sourced P. monodon broodstock. This study presents a comprehensive investigation of the presence and level of detection of endemic pathogen targets in wild-sourced P. monodon broodstock collected from the two primary sources of supply for the Australian shrimp aquaculture industry using quantitative polymerase chain reaction (qPCR). Broodstock pleopod samples (N = 7472) were analysed by TaqMan qPCR for the detection of six viral pathogens. In total, 44.9% of wild-sourced broodstock were positive for the detection of at least one pathogen target. White spot syndrome virus and yellow head virus-1 were not detected in any sample. Infectious hypodermal haematopoietic necrosis virus (30%) and gill-associated virus (28.1%) were the most prevalent pathogen targets detected. Whenzhou (syn. Wenzhou) shrimp virus-2 and yellow head virus-7 were each cumulatively detected in less than 3% of broodstock samples. Geographic source, sex and year of collection of broodstock significantly influenced prevalence of detection. The current study will be valuable to the Australian shrimp aquaculture industry to improve understanding of the presence of pathogens in wild-sourced broodstock, along with informing management decisions related to wild broodstock collection and associated biosecurity practices

Using bacterial whole genome sequencing to identify toxin genes associated with disease outbreaks in black tiger shrimp (Penaeus monodon) aquaculture production

Vibrio-related diseases cause significant economic impact on global shrimp production. Although toxin expression is a well-established mechanism of Vibrio-related disease in humans, the role of toxin expression in Vibrio disease in aquaculture generally is not well defined. The current study investigated a sustained, rapid onset, mass mortality at a commercial tiger prawn, Penaeus monodon, hatchery. Affected shrimp were between mysis-2 and post-larvae-15. Disease outbreaks were prevented through prophylactic treatment with oxytetracycline, suggesting a bacterial-related causative agent. Conversely, mortality was not reduced with erythromycin treatment. Whole genome sequencing (WGS) using the Illumina Nextera XT protocol performed on mixed microbial cultures from erythromycin and non-erythromycin infused thiosulphate-citrate-bile salts-sucrose (TCBS) TCBS agar on a MiSeq, and postlarval samples on a HiSeq. The WGS revealed several Vibrio-related sequences dominated by reads with highest homology to Vibrio harveyi and Vibrio alginolyticus. In addition, a range of putative virulence genes encoding for antibiotic resistance and toxin production were identified. Taqman qPCR assays were designed to specifically quantify four of the putative toxin-genes found, namely the Zonula occludens toxin (ZOT), hemolysin d toxin (HylD), YaFO toxin-antitoxin and Repeats–in-Toxin (RTX) genes. The qPCR assays confirmed the presence of the toxin target genes with low cycle threshold value (Ct) in the bacterial cultures and postlarval samples. Specifically, the ZOT and HylD genes were detected in high copy number in the non-erythromycin and erythromycin-treated cultures. Although the detection of toxin-genes does not demonstrate causation of mortality, the application of WGS combined with qPCR analysis has revealed the presence of a range of virulence factors within the hatchery system and allowed a rapid implementation of management protocols to prevent entry of genetically toxin-armed Vibrio spp. until more conclusive studies into disease mechanisms could be conducted

Bacterial signatures of productivity decay in Penaeus monodon ponds infected with PirA toxin

status: publishe

Bacterial signatures of productivity decay in Penaeus monodon ponds infected with PirA toxin

The clear relationship between the microbiome and the general well-being of metazoans has motivated the characterization of bacterial communities in cultured species for future microbiome monitoring and modulation to improve productivity. To study the bacterial diversity associated with farmed adult P. monodon at harvest, guts, gastric mills (GM), pond water and sediments were investigated using next-generation sequencing technology in two control ponds (CP1 and CP2) where animals showed a healthy appearance, and two low productive ponds (LP1 and LP2) where animals showed signs of disease. Animals from CP2 were on average at least 4 g heavier than animals from other ponds, and the final yield of both CP was more than double that of LP. LP2 showed the lowest diversity indices, which can potentially be attributed to high abundance of Vibrio spp. and warm water conditions (31.6 +/- 0.3 degrees C on average). The structure of the bacterial community in the gut, GM and water samples was different between CP and LP. Vibrio spp. and anaerobic bacteria (e.g. Fusibacter) were enriched in the gastrointestinal tract of animals from LP (LDA >= 4). While Vibrio can potentially act against the host and other members of the bacterial community, Fusibacter might be an indicator of sulfur compounds accumulation in the animal as the hepatopancreas becomes affected by a PirA toxin. Enrichment of Cyanobacteria in the water (LDA = 4.38) and members of Desulfobacteraceae in sediments of LP (5% on average) could be environmental stress indicators in summer conditions. Characterizing bacterial microbiomes in aquaculture is important to detect indicators of health and productivity that can be used as monitoring tools in the animal s gastrointestinal tract and the environment, ultimately enabling a targeted modulation of the bacterial community for improved production