Principles and Methods of Counteracting Harmful Salmon–Arthropod Interactions in Salmon Farming: Addressing Possibilities, Limitations, and Future Options

The arthropod salmon louse (Lepeophtheirus salmonis) is a major threat to Atlantic salmon aquaculture and wild salmonids. Essentially like in monoculture, very high concentrations of susceptible hosts may result in high reproduction and severe production of waves of pests. Pest management is crucial both for fish health and protection of wild fish populations from aquaculture influence. Various methods have been utilized to control salmon lice infestations, such as pesticide use, physical treatments, construction modifications, fallowing, breeding, vaccination, and biological control. Most of the methods are partially successful, but none completely fulfills the necessary pest control strategy. Like in agriculture, lice/pest management is an arms race, but the marine environment makes it even more difficult to precisely hit the target pest and avoid unintended negative effects on general wildlife. In this study, we provide an overview of the methods and principles of salmon lice management and address current possibilities and limitations. We also highlight the potential of emerging strategies and enabling technologies, like genome editing, RNA interference, and machine learning, in arthropod management in aquaculture.

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Protective Immunization of Atlantic Salmon (Salmo salar L.) against Salmon Lice (Lepeophtheirus salmonis) Infestation

Vaccines ◽

10.3390/vaccines10010016 ◽

2021 ◽

Vol 10 (1) ◽

pp. 16

Author(s):

Haitham Tartor ◽

Marius Karlsen ◽

Rasmus Skern-Mauritzen ◽

Adérito Luis Monjane ◽

Charles McLean Press ◽

...

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

Vaccine Dose ◽

Lepeophtheirus Salmonis ◽

Vaccine Formulation ◽

Negative Effects ◽

Specific Antibodies ◽

Salmon Lice ◽

Dose Dependent ◽

Higher Doses

Vaccination against salmon lice (Lepeophtheirus salmonis) is a means of control that averts the negative effects of chemical approaches. Here, we studied the immunogenicity and protective effect of a vaccine formulation (based on a salmon lice-gut recombinant protein [P33]) against Lepeophtheirus salmonis infestation in Atlantic salmon in a laboratory-based trial. Our findings revealed that P33 vaccine can provide a measure of protection against immature and adult salmon lice infestation. This protection seemed to be vaccine dose-dependent, where higher doses resulted in lower parasitic infestation rates. We also provide immunological evidence confirming that P33-specific immune response can be triggered in Atlantic salmon after P33 vaccination, and that production of P33-specific antibodies in blood can be detected in vaccinated fish. The negative correlation between P33-specific IgM in salmon plasma and salmon lice numbers on vaccinated fish suggests that protection against lice can be mediated by the specific antibody in salmon plasma. The success of P33 vaccination in protecting salmon against lice confirms the possibility of employing the hematophagous nature of the parasite to deliver salmon-specific antibodies against lice-gut proteins.

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The planktonic stages of the salmon louse (Lepeophtheirus salmonis) are tolerant of end-of-century pCO2 concentrations

PeerJ ◽

10.7717/peerj.7810 ◽

2019 ◽

Vol 7 ◽

pp. e7810 ◽

Cited By ~ 4

Author(s):

Cameron R.S. Thompson ◽

David M. Fields ◽

Reidun M. Bjelland ◽

Vera B.S. Chan ◽

Caroline M.F. Durif ◽

...

Keyword(s):

Ocean Acidification ◽

Fatty Acid Content ◽

Lepeophtheirus Salmonis ◽

Free Living ◽

Salmon Aquaculture ◽

Salmon Lice ◽

Host Parasite ◽

Lecithotrophic Development ◽

High Treatment ◽

Marine Parasite

The copepod Lepeophtheirus salmonis is an obligate ectoparasite of salmonids. Salmon lice are major pests in salmon aquaculture and due to its economic impact Lepeophtheirus salmonis is one of the most well studied species of marine parasite. However, there is limited understanding of how increased concentration of pCO2 associated with ocean acidification will impact host-parasite relationships. We investigated the effects of increased pCO2 on growth and metabolic rates in the planktonic stages, rearing L. salmonis from eggs to 12 days post hatch copepodids under three treatment levels: Control (416 µatm), Mid (747 µatm), and High (942 µatm). The pCO2 treatment had a significant effect on oxygen consumption rate with the High treatment animals exhibiting the greatest respiration. The treatments did not have a significant effect on the other biological endpoints measured (carbon, nitrogen, lipid volume, and fatty acid content). The results indicate that L. salmonis have mechanisms to compensate for increased concentration of pCO2and that populations will be tolerant of projected future ocean acidification scenarios. The work reported here also describes catabolism during the lecithotrophic development of L. salmonis, information that is not currently available to parameterize models of dispersal and viability of the planktonic free-living stages.

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The metachor as a characteristic of the association of electrolytes in aqueous solutions

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19841061 ◽

1984 ◽

Vol 49 (5) ◽

pp. 1061-1078 ◽

Cited By ~ 1

Author(s):

Jiří Čeleda ◽

Stanislav Škramovský

Keyword(s):

Aqueous Solutions ◽

Apparent Volume ◽

Solutions Of Electrolytes ◽

Molal Volumes ◽

The Difference ◽

High Concentrations ◽

Experimental Values ◽

Suitable Characteristic ◽

Association Of Ions ◽

Very High

Based on the earlier paper introducing a concept of the apparent parachor of a solute in the solution, we have eliminated in the present work algebraically the effect which is introduced into this quantity by the additivity of the apparent molal volumes. The difference remaining from the apparent parachor after substracting the contribution corresponding to the apparent volume ( for which the present authors suggest the name metachor) was evaluated from the experimental values of the surface tension of aqueous solutions for a set of 1,1-, 1,2- and 2,1-valent electrolytes. This difference showed to be independent of concentration up to the very high values of the order of units mol dm-3 but it was directly proportional to the number of the free charges (with a proportionality factor 5 ± 1 cm3 mol-1 identical for all studied electrolytes). The metachor can be, for this reason, a suitable characteristic for detection of the association of ions and formation of complexes in the solutions of electrolytes, up to high concentrations where other methods are failing.

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The protective effect of the Phe362Tyr mutation in salmon lice’ (Lepeophtheirus salmonis) AChE when exposed to full-scale azamethiphos bath treatments

Aquaculture ◽

10.1016/j.aquaculture.2019.03.016 ◽

2019 ◽

Vol 505 ◽

pp. 517-522 ◽

Cited By ~ 2

Author(s):

Kari Olli Helgesen ◽

Kristoffer Røyset ◽

Vidar Aspehaug ◽

Peder A. Jansen

Keyword(s):

Protective Effect ◽

Full Scale ◽

Lepeophtheirus Salmonis ◽

Salmon Lice

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Nitrification Process in a Nuclear Wastewater with High Load of Nitrogen, Uranium and Organic Matter under ORP Controlled

Water ◽

10.3390/w13111607 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1607

Author(s):

Mariano Venturini ◽

Ariana Rossen ◽

Patricia Silva Paulo

Keyword(s):

Ammonia Oxidation ◽

High Load ◽

Nuclear Fuels ◽

Monod Model ◽

Nernst Equation ◽

Nitrification Process ◽

Real Wastewater ◽

High Concentrations ◽

Wastewater Samples ◽

Very High

To produce nuclear fuels, it is necessary to convert uranium′s ore into UO2-ceramic grade, using several quantities of kerosene, methanol, nitric acid, ammonia, and, in low level, tributyl phosphate (TBP). Thus, the effluent generated by nuclear industries is one of the most toxic since it contains high concentrations of dangerous compounds. This paper explores biological parameters on real nuclear wastewater by the Monod model in an ORP controlled predicting the specific ammonia oxidation. Thermodynamic parameters were established using the Nernst equation to monitor Oxiders/Reductors relationship to obtain a correlation of these parameters to controlling and monitoring; that would allow technical operators to have better control of the nitrification process. The real nuclear effluent is formed by a mixture of two different lines of discharges, one composed of a high load of nitrogen, around 11,000 mg/L (N-NH4+-N-NO3−) and 600 mg/L Uranium, a second one, proceeds from uranium purification, containing TBP and COD that have to be removed. Bioprocesses were operated on real wastewater samples over 120 days under controlled ORP, as described by Nernst equations, which proved to be a robust tool to operate nitrification for larger periods with a very high load of nitrogen, uranium, and COD.

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Halogenated Volatile Organic Compounds in Water Samples and Inorganic Elements Levels in Ores for Characterizing a High Anthropogenic Polluted Area in the Northern Latium Region (Italy)

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18041628 ◽

2021 ◽

Vol 18 (4) ◽

pp. 1628

Author(s):

Mario Vincenzo Russo ◽

Ivan Notardonato ◽

Alberto Rosada ◽

Giuseppe Ianiri ◽

Pasquale Avino

Keyword(s):

Organic Compounds ◽

Mean Value ◽

Greenhouse Crops ◽

River Waters ◽

Liquid Liquid Extraction ◽

Volatile Organic ◽

High Concentrations ◽

Very High ◽

Inorganic Fraction

This paper shows a characterization of the organic and inorganic fraction of river waters (Tiber and Marta) and ores/soil samples collected in the Northern Latium region of Italy for evaluating the anthropogenic/natural source contribution to the environmental pollution of this area. For organic compounds, organochloride volatile compounds in Tiber and Marta rivers were analyzed by two different clean-up methods (i.e., liquid–liquid extraction and static headspace) followed by gas chromatography–electron capture detector (GC-ECD) analysis. The results show very high concentrations of bromoform (up to 1.82 and 3.2 µg L−1 in Tiber and Marta rivers, respectively), due to the presence of greenhouse crops, and of chloroform and tetrachloroethene, due to the presence of handicrafts installations. For the qualitative and quantitative assessment of the inorganic fraction, it is highlighted the use of a nuclear analytical method, instrumental neutron activation analysis, which allows having more information as possible from the sample without performing any chemical-physical pretreatment. The results have evidenced high levels of mercury (mean value 88.6 µg g−1), antimony (77.7 µg g−1), strontium (12,039 µg g−1) and zinc (103 µg g−1), whereas rare earth elements show levels similar to the literature data. Particular consideration is drawn for arsenic (414 µg g−1): the levels found in this paper (ranging between 1 and 5100 µg g−1) explain the high content of such element (as arsenates) in the aquifer, a big issue in this area.

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Study on farmers’ Pest management strategy, knowledge on pesticide safety and practice of pesticide use at Bhaktapur district, Nepal

Cogent Food & Agriculture ◽

10.1080/23311932.2021.1916168 ◽

2021 ◽

Vol 7 (1) ◽

pp. 1916168

Author(s):

Susan Thapa ◽

Gaetano Piras ◽

Sudesh Thapa ◽

Arjun Goswami ◽

Prabas Bhandari ◽

...

Keyword(s):

Pest Management ◽

Management Strategy ◽

Pesticide Use ◽

Pesticide Safety

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THE SELECTIVE PROTEOLYTIC ENZYME INHIBITORY ACTION OF BENZETHONIUM CHLORIDE

Canadian Journal of Biochemistry and Physiology ◽

10.1139/y60-004 ◽

1960 ◽

Vol 38 (1) ◽

pp. 25-32 ◽

Cited By ~ 4

Author(s):

Ivan T. Beck ◽

E. Pinter ◽

R. D. McKenna ◽

H. Griff

Keyword(s):

Subcutaneous Injection ◽

Proteolytic Enzyme ◽

Inhibitory Action ◽

Hemorrhagic Pancreatitis ◽

Benzethonium Chloride ◽

Tryptic Activity ◽

High Concentrations ◽

Acute Hemorrhagic Pancreatitis ◽

Very High

Acute hemorrhagic pancreatitis in humans is thought to be perpetuated by the autolytic processes catalyzed by trypsin and lipase. This study is an integral part of our search for trypsin and lipase inhibitors to be used in the treatment of this disease.Benzethonium chloride was found to inhibit tryptic activity in vitro. The proteolytic activity of rabbit's serum was inhibited, and the inhibition was most pronounced 6 to 12 hours after the subcutaneous injection of the compound. Fibrinolysin was also inhibited in vitro but benzethonium chloride had no inhibitory action on chymotrypsin, pepsin, or lipase.Serum proteins in vitro were precipitated only with very high concentrations of the compound. No significant protein changes were observed in sera of rabbits after the subcutaneous injection of the compound.

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Arginine Inhibits Serpins

Clinical and Applied Thrombosis/Hemostasis ◽

10.1177/1076029606299047 ◽

2007 ◽

Vol 13 (2) ◽

pp. 213-218

Author(s):

Thomas W. Stief

Keyword(s):

Esterase Activity ◽

Serine Proteases ◽

Biological Fluid ◽

Microtiter Plate ◽

Human Albumin ◽

Amidolytic Activity ◽

Peptide Substrates ◽

Plate Reader ◽

High Concentrations ◽

Very High

Serine protease inactivators (serpins) are important regulators in biochemistry. Often it is necessary to block the serpin action, that is, to stabilize the sample. The guanidine group of arginine is the ligand for the active center pocket of many serine proteases. Arginine or guanidine inhibits serine proteases, and arginine belongs to the reactive P1-P1' center of many serpins. The plasmatic antithrombin, antiplasmin, or anti-C1-esterase activity was determined: A total of 20 µL of pooled normal plasma or 7% human albumin was added to 100 µL of 0—2.67 M arginine, pH 8.6, 10 µL of 26 mIU/mL thrombin in 7% human albumin, and 30 µL of 1.7 mM CHG-Ala-Arg-pNA (37°C). ΔA at 405 nm was determined, by using a microtiter plate reader. Thrombin was substituted by plasmin or C1-esterase, and the chromogenic peptide substrates <Glu-Phe-Lys-pNA or MeOC-Lys(eCBO)-Gly-Arg-pNA, respectively, were used. The IC50 of arginine against plasmatic antithrombin activity is 580 mM; the IC 25 is 440 mM. The IC25 of arginine against plasmatic α 2-antiplasmin or C1-inactivator is 1650 mM. The amidolytic activity of thrombin, plasmin, and C1-esterase is inhibited similarly by arginine: the IC50 for arginine against the amidolytic activity of these proteases is about 400 mM. Arginine at very high concentrations inhibits serpins. This is important, if stabilization of a biological fluid is a prerequisite for valid activities of serine proteases. In addition, these high concentrations of arginine might be a new gentle principle to inhibit pathogens that need serpins for their pathophysiology.

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