Search results for "Aquaculture"
showing 8 items of 348 documents
Discharge management in fresh and brackish water RAS: Combined phosphorus removal by organic flocculants and nitrogen removal in woodchip reactors
2020
The current study combined P and N removal using organic flocculant chemicals and woodchip bioreactors in both freshwater and brackish water (7 ppm) recirculating aquaculture systems (RAS). The use of carbon (C) containing flocculant chemicals in the process was hypothesized to further stimulate C-demanding N removal (denitrification) in bioreactors. The trial of combined P and N removal consisted of four treatments: freshwater and brackish water RAS with and without the addition of supernatant from flocculation process to the woodchip reactor. Duplicate woodchip reactors were used per treatment and the trial was run for six weeks. 56 % and 49 % of P was removed from fresh and brackish slud…
Warming temperatures and ectoparasitic sea lice impair internal organs in juvenile Atlantic salmon
2021
As a consequence of climate change and open net-pen salmon farming, wild Atlantic salmon Salmo salar are increasingly likely to encounter elevated temperatures and parasite abundances during their early marine migration. Such stressors can compromise fitness by diminishing liver energy stores and impairing cardiac muscle. To assess whether temperature and infestation by salmon lice Lepeophtheirus salmonis are important correlates of liver energy stores and cardiac muscle performance in juvenile salmon, we experimentally infested fish at 3 abundances of louse infestation (zero, low, and high) and 5 temperatures (10, 13, 16, 19, and 22°C). At the end of the experiment (i.e. when sea lice reac…
Sequential infection can decrease virulence in a fish–bacterium–fluke interaction: Implications for aquaculture disease management
2019
Hosts are typically infected with multiple strains or genotypes of one or several parasite species. These infections can take place simultaneously, but also at different times, i.e. sequentially, when one of the parasites establishes first. Sequential parasite dynamics are common in nature, but also in intensive farming units such as aquaculture. However, knowledge of effects of previous exposures on virulence of current infections in intensive farming is very limited. This is critical as consecutive epidemics and infection history of a host could underlie failures in management practises and medical intervention of diseases. Here, we explored effects of timing of multiple infection on viru…
Innovative technologies for packaging, preservation, shelf-life extension and traceability of the aquaculture and fishery products
2022
Haemolymphatic Parameters in Two Aquaculture Crustacean Species Cherax destructor (Clark, 1836) and Cherax quadricarinatus (Von Martens, 1868)
2022
In the last few years, there has been a notable development in the breeding of freshwater shrimp (astaciculture), which involved various species and in particular, the two Australian Parastacidae species, Cherax destructor and Cherax quadricarinatus. Information about the haemolymphatic parameters of these two species is fragmentary, and filling these gaps becomes important given their importance in aquaculture. Cellular and biochemical parameters were analyzed in both species to create a reference baseline for these parameters to identify the state of welfare or suffering of these animals. The results showed that the total haemocyte count, haemocyte subpopulations, enzymatic activities and…
EFFECTS OF THE ENRICHED-ORGANIC DIETS COMPOSITION ON EUROPEAN SEA BASS (Dicentrarchus labrax) NEW TOOLS FOR FISH WELFARE EVALUATION IN AQUACULTURE
2021
In recent years, concern for the welfare of animals, including fish, has a strong impact on public opinion, putting pressure not only on producers and the scientific community, but also on institution to guarantee adequate "standards” for animal welfare. The market today challenges the production capacity of aquaculture by asking for products with consistently high quality. Unlike other farming methods, there is a lack of scientific information on the welfare of fish reared under intensive aquaculture conditions. Among the various aspects that characterize aquaculture, the increase in fish welfare has an impact on public opinion also for economic reasons whereby is very important to keep an…
Rearing background and exposure environment together explain higher survival of aquaculture fish during a bacterial outbreak
2019
1.Parasitic diseases represent one of the greatest challenges for aquaculture worldwide and there is an increasing emphasis on ecological solutions to prevent infections. One proposed solution is enriched rearing, where traditional stimulus‐poor rearing tanks are equipped with different types of structures to increase habitat complexity. Such spatial enrichment is known to increase survival of fish during parasite epidemics, but the underlying mechanisms are still unclear. 2.We studied whether enriched rearing affected infection of an important fish pathogen Flavobacterium columnare in young Atlantic salmon (Salmo salar) and sea‐migrating brown trout (Salmo trutta). First, we used natural b…
The Use of Stable Isotope Ratio Analysis to Trace European Sea Bass (D. labrax) Originating from Different Farming Systems
2020
This study aimed to determine whether isotopic ratio mass spectrometry (IRMS) can discriminate farmed European sea bass according to different farming systems and geographic origins. Dicentrarchus labrax of commercial size from three different rearing systems (concrete tank inland, sea cages, and extensive methods in valleys or salt works) were collected at the trading period (autumn&ndash