Experimental Transmission of Infectious Pancreatic Necrosis Virus from the Blue Mussel, Mytilus edulis, to Cohabitating Atlantic Salmon (Salmo salar) Smolts

Integrated multitrophic aquaculture (IMTA) reduces the environmental impacts of commercial aquaculture systems by combining the cultivation of fed species with extractive species. Shellfish play a critical role in IMTA systems by filter-feeding particulate-bound organic nutrients. As bioaccumulating organisms, shellfish may also increase disease risk on farms by serving as reservoirs for important finfish pathogens such as infectious pancreatic necrosis virus (IPNV). The ability of the blue mussel (Mytilus edulis) to bioaccumulate and transmit IPNV to naive Atlantic salmon (Salmo salar) smolts was investigated. To determine the ability of mussels to filter and accumulate viable IPNV, mussels were held in water containing log 4.6 50% tissue culture infective dose(s) (TCID(50)) of the West Buxton strain of IPNV ml(−1). Viable IPNV was detected in the digestive glands (DGs) of IPNV-exposed mussels as early as 2 h postexposure. The viral load in mussel DG tissue significantly increased with time and reached log 5.35 ± 0.25 TCID(50) g of DG tissue(−1) after 120 h of exposure. IPNV titers never reached levels that were significantly greater than that in the water. Viable IPNV was detected in mussel feces out to 7 days postdepuration, and the virus persisted in DG tissues for at least 18 days of depuration. To determine whether IPNV can be transmitted from mussels to Atlantic salmon, IPNV-exposed mussels were cohabitated with naive Atlantic salmon smolts. Transmission of IPNV did occur from mussels to smolts at a low frequency. The results demonstrate that a nonenveloped virus, such as IPNV, can accumulate in mussels and be transferred to naive fish

Culture of Sargassum in Korea: Techniques and Potential for Culture in the U.S.

In an effort to develop suitable culture techniques for macroalgae in the Northeast, this guide reviews the current knowledge of Sargassum biology and reports on culture techniques learned during a research exchange between the United States (NOAA Sea Grant) and South Korea (National Fisheries Research and Development Institute)

Culture of Sea Cucumbers in Korea: A guide to Korean methods and the local sea cucumber in the Northeast U.S.

A paper exploring the potential to grow Korean sea cucumbers in the Northeast of the United States. This paper examines the life history and biology of the Korean cucumber (Cucumaria Frondosa), Korean hatchery culture techniques, Korean sea cucumber culture process, and the viability of culturing the Korean sea cucumber in the Northeast

Culture of Sea Cucumbers in Korea: A Guide to Korean Methods and the Local Sea Cucumber in the Northeast U.S.

In an effort to develop suitable culture techniques for sea cucumber (Cucumaria frondosa) in the Northeast, this guide reviews the current knowledge of C. frondosa biology and reports on techniques for the hatchery culture of the Japanese sea cucumber Apostichopus japonicus learned during a research exchange between the United States (NOAA Sea Grant) and South Korea (National Fisheries Research and Development Institute). The final portion of the guide discusses the potential adoption of the culture techniques for A. japonicus for use with C. frondosa

Reduction in BACE1 decreases body weight, protects against diet-induced obesity and enhances insulin sensitivity in mice

Insulin resistance and impaired glucose homoeostasis are important indicators of Type 2 diabetes and are early risk factors of AD (Alzheimer's disease). An essential feature of AD pathology is the presence of BACE1 (β-site amyloid precursor protein-cleaving enzyme 1), which regulates production of toxic amyloid peptides. However, whether BACE1 also plays a role in glucose homoeostasis is presently unknown. We have used transgenic mice to analyse the effects of loss of BACE1 on body weight, and lipid and glucose homoeostasis. BACE1−/− mice are lean, with decreased adiposity, higher energy expenditure, and improved glucose disposal and peripheral insulin sensitivity than wild-type littermates. BACE1−/− mice are also protected from diet-induced obesity. BACE1-deficient skeletal muscle and liver exhibit improved insulin sensitivity. In a skeletal muscle cell line, BACE1 inhibition increased glucose uptake and enhanced insulin sensitivity. The loss of BACE1 is associated with increased levels of UCP1 (uncoupling protein 1) in BAT (brown adipose tissue) and UCP2 and UCP3 mRNA in skeletal muscle, indicative of increased uncoupled respiration and metabolic inefficiency. Thus BACE1 levels may play a critical role in glucose and lipid homoeostasis in conditions of chronic nutrient excess. Therefore strategies that ameliorate BACE1 activity may be important novel approaches for the treatment of diabetes

THE SPREAD OF THE SALMON LOUSE

Lepeophtheirus salmonis or salmon lice infections are one of the most prevalent parasitic infections in the salmon aquaculture industry. Salmon lice cause an estimated loss of 3 % of the production of Maine's salmon industry annually. Within the State of Maine only a portion of the farm sites experience salmon lice infections on an annual basis, while some sites have never had infections of Lepeophtheirus salmonis. Because of the potential impact that salmon lice infections could mean to those areas that to date have been fiee of L. salmonis infections, there has been concern both on the part of the State and the industry to prevent any fkther spread of the parasite by farming activities. This research evaluated three potential methods for preventing salmon lice fiom developing to the infective copepodid stage. In order to evaluate the effects of chlorine, iodine and desiccation on the development of salmon lice eggs a new culture system for L. salmonis was developed at the University of Maine. The system allowed for egg strings to be raised withinindividual culture chambers and utilized recirculation technology. Before being cultured L. salmonis egg strings were exposed to one of eight treatments: 200 ppm of chlorine or iodine for one minute, 500 ppm of chlorine or iodine for one minute or 10 minutes, o

Investigations into the ecology and interactions of pathogens within an integrated multi-trophic aquaculture farm

The recent research focus on integrated multi-trophic aquaculture (IMTA) is redefining the aquaculture industry's approach to intensive aquaculture. More sustainable farm model systems that include multiple farm products with integrated trophic levels are being developed. While these systems may be economically and environmentally more sustainable, it is important to realize that integrating farm products also changes disease risk on farms. This is illustrated by examining how finfish disease risk can increase or decrease depending on the pathogen in a simple finfish / blue mussel (Mytilus edulis) IMTA system. Mussels bio-accumulate and repackage the opportunistic pathogen, Vibrio anguillarum, into infectious fecal particles increasing the potential risk of infection and creating new transmission pathways. In contrast, mussels appear to inactivate the viral pathogen, Infectious Salmon Anemia Virus (ISAV) and potentially serving a role in reducing the transmission of the virus onto and off of IMTA farms. To understand disease risk on IMTA farms, it is no longer adequate to simply investigate how a given pathogen interacts with its host under a range of environmental conditions. Evaluating the disease risk in IMTA systems requires a better understanding of how pathogens may potentially interact with all of the components of the farm system, while recognizing new potential pathways that may be created or enhanced within and by the system its self. Through a more comprehensive understanding of these potential interactions farmers can apply a range of bio-security and best management practices to limit the risk of disease on IMTA farms. With good management IMTA farms should not increase the risk of disease, but may actually reduce the spread of pathogens in some situations

Investigations Into the Ecology and Interactions of Pathogens Within an Integrated Multi-Trophic Aquaculture Farm

The recent research focus on integrated multi-trophic aquaculture (IMTA) is redefining the aquaculture industry’s approach to intensive aquaculture. More sustainable farm model systems that include multiple farm products with integrated trophic levels are being developed. While these systems may be economically and environmentally more sustainable, it is important to realize that integrating farm products also changes disease risk on farms. This is illustrated by examining how finfish disease risk can increase or decrease depending on the pathogen in a simple finfish / blue mussel (Mytilus edulis) IMTA system. Mussels bio-accumulate and repackage the opportunistic pathogen, Vibrio anguillarum, into infectious fecal particles increasing the potential risk of infection and creating new transmission pathways. In contrast, mussels appear to inactivate the viral pathogen, Infectious Salmon Anemia Virus (ISAV) and potentially serving a role in reducing the transmission of the virus onto and off of IMTA farms. To understand disease risk on IMTA farms, it is no longer adequate to simply investigate how a given pathogen interacts with its host under a range of environmental conditions. Evaluating the disease risk in IMTA systems requires a better understanding of how pathogens may potentially interact with all of the components of the farm system, while recognizing new potential pathways that may be created or enhanced within and by the system its self. Through a more comprehensive understanding of these potential interactions farmers can apply a range of bio-security and best management practices to limit the risk of disease on IMTA farms. With good management IMTA farms should not increase the risk of disease, but may actually reduce the spread of pathogens in some situations