scholarly journals Factors associated with baseline mortality in Norwegian Atlantic salmon farming

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Victor H. S. Oliveira ◽  
Katharine R. Dean ◽  
Lars Qviller ◽  
Carsten Kirkeby ◽  
Britt Bang Jensen
Keyword(s):  
Atlantic Salmon ◽  
Algal Blooms ◽  
Disease Outbreaks ◽  
Economic Loss ◽  
Sea Lice ◽  
Factors Associated ◽  
Farmed Salmon ◽  
Infectious Disease Outbreaks ◽  
Baseline Mortality ◽  
Significant Economic Loss

AbstractIn 2019, it was estimated that more than 50 million captive Atlantic salmon in Norway died in the final stage of their production in marine cages. This mortality represents a significant economic loss for producers and a need to improve welfare for farmed salmon. Single adverse events, such as algal blooms or infectious disease outbreaks, can explain mass mortality in salmon cages. However, little is known about the production, health, or environmental factors that contribute to their baseline mortality during the sea phase. Here we conducted a retrospective study including 1627 Atlantic salmon cohorts put to sea in 2014–2019. We found that sea lice treatments were associated with Atlantic salmon mortality. In particular, the trend towards non-medicinal sea lice treatments, including thermal delousing, increases Atlantic salmon mortality in the same month the treatment is applied. There were differences in mortality among production zones. Stocking month and weight were other important factors, with the lowest mortality in smaller salmon stocked in August–October. Sea surface temperature and salinity also influenced Atlantic salmon mortality. Knowledge of what affects baseline mortality in Norwegian aquaculture can be used as part of syndromic surveillance and to inform salmon producers on farming practices that can reduce mortality.

scholarly journals Computational Modeling of Interventions and Protective Thresholds to Prevent Disease Transmission in Deploying Populations

2014 ◽  
Vol 2014 ◽  
pp. 1-17 ◽  
Author(s):  
Colleen Burgess ◽  
Angela Peace ◽  
Rebecca Everett ◽  
Buena Allegri ◽  
Patrick Garman
Keyword(s):  
Computational Modeling ◽  
Disease Transmission ◽  
Disease Outbreaks ◽  
Economic Loss ◽  
Vaccine Preventable Disease ◽  
Humanitarian Relief ◽  
Military Populations ◽  
Relief Efforts ◽  
Efficient Transmission ◽  
Significant Economic Loss

Military personnel are deployed abroad for missions ranging from humanitarian relief efforts to combat actions; delay or interruption in these activities due to disease transmission can cause operational disruptions, significant economic loss, and stressed or exceeded military medical resources. Deployed troops function in environments favorable to the rapid and efficient transmission of many viruses particularly when levels of protection are suboptimal. When immunity among deployed military populations is low, the risk of vaccine-preventable disease outbreaks increases, impacting troop readiness and achievement of mission objectives. However, targeted vaccination and the optimization of preexisting immunity among deployed populations can decrease the threat of outbreaks among deployed troops. Here we describe methods for the computational modeling of disease transmission to explore how preexisting immunity compares with vaccination at the time of deployment as a means of preventing outbreaks and protecting troops and mission objectives during extended military deployment actions. These methods are illustrated with five modeling case studies for separate diseases common in many parts of the world, to show different approaches required in varying epidemiological settings.

scholarly journals How to improve adherence with quarantine: Rapid review of the evidence.

2020 ◽  
Author(s):  
Rebecca Webster ◽  
Samantha Brooks ◽  
Louise Smith ◽  
Lisa Woodland ◽  
Simon Wessely ◽  
...  
Keyword(s):  
Public Health ◽  
Infectious Disease ◽  
Social Norms ◽  
Perceived Risk ◽  
Disease Outbreaks ◽  
Rapid Review ◽  
Factors Associated ◽  
Infectious Disease Outbreaks ◽  
Perceived Benefit ◽  
Public Health Officials

Objectives: The January 2020 outbreak of coronavirus has once again thrown the vexed issue of quarantine into the spotlight, with many countries asking their citizens to ‘self-isolate’ if they have potentially come into contact with the infection. However, adhering to quarantine is difficult. Decisions on how to apply quarantine should be based on the best available evidence to increase the likelihood of people adhering to protocols. We conducted a rapid review to identify factors associated with adherence to quarantine during infectious disease outbreaks.Study design Rapid evidence review.Methods: We searched Medline, PsycINFO and Web of Science for published literature on the reasons for and factors associated with adherence to quarantine during an infectious disease outbreak.Results: We found 3163 papers and included 14 in the review. Adherence to quarantine ranged from as little as 0 up to 92.8%. The main factors which influenced or were associated with adherence decisions were the knowledge people had about the disease and quarantine procedure, social norms, perceived benefits of quarantine and perceived risk of the disease, as well as practical issues such as running out of supplies or the financial consequences of being out of work. Conclusions: People vary in their adherence to quarantine during infectious disease outbreaks. To improve this, public health officials should provide a timely, clear rationale for quarantine and information about protocols; emphasise social norms to encourage this altruistic behaviour; increase the perceived benefit that engaging in quarantine will have on public health; and ensure that sufficient supplies of food, medication and other essentials are provided.

scholarly journals How to improve adherence with quarantine: Rapid review of the evidence

2020 ◽  
Author(s):  
Rebecca K. Webster ◽  
Samantha K. Brooks ◽  
Louise E. Smith ◽  
Lisa Woodland ◽  
Simon Wessely ◽  
...  
Keyword(s):  
Public Health ◽  
Infectious Disease ◽  
Social Norms ◽  
Perceived Risk ◽  
Disease Outbreaks ◽  
Rapid Review ◽  
Factors Associated ◽  
Infectious Disease Outbreaks ◽  
Perceived Benefit ◽  
Public Health Officials

AbstractObjectivesThe January 2020 outbreak of coronavirus has once again thrown the vexed issue of quarantine into the spotlight, with many countries asking their citizens to ‘self-isolate’ if they have potentially come into contact with the infection. However, adhering to quarantine is difficult. Decisions on how to apply quarantine should be based on the best available evidence to increase the likelihood of people adhering to protocols. We conducted a rapid review to identify factors associated with adherence to quarantine during infectious disease outbreaks.Study designRapid evidence review.MethodsWe searched Medline, PsycINFO and Web of Science for published literature on the reasons for and factors associated with adherence to quarantine during an infectious disease outbreak.ResultsWe found 3163 papers and included 14 in the review. Adherence to quarantine ranged from as little as 0 up to 92.8%. The main factors which influenced or were associated with adherence decisions were the knowledge people had about the disease and quarantine procedure, social norms, perceived benefits of quarantine and perceived risk of the disease, as well as practical issues such as running out of supplies or the financial consequences of being out of work.ConclusionsPeople vary in their adherence to quarantine during infectious disease outbreaks. To improve this, public health officials should provide a timely, clear rationale for quarantine and information about protocols; emphasise social norms to encourage this altruistic behaviour; increase the perceived benefit that engaging in quarantine will have on public health; and ensure that sufficient supplies of food, medication and other essentials are provided.

The poor potential of cunner, Tautogolabrus adspersus, to act as cleaner fish in removing sea lice (Caligus elongatus) from farmed salmon in eastern Canada

1995 ◽  
Vol 52 (S1) ◽  
pp. 175-177 ◽  
Author(s):  
B.M. MacKinnon
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Sea Lice ◽  
Tautogolabrus Adspersus ◽  
Eastern Canada ◽  
Cleaner Fish ◽  
Farmed Salmon ◽  
The Poor ◽  
Fouling Organisms ◽  
Farmed Atlantic Salmon

Cunner, Tautogolabrus adspersus, were found not to be good candidates for removal of sea lice, Caligus elongatus, from farmed Atlantic salmon (Salmo salar) during seapen trials conducted in Passamoquoddy Bay, N.B. In laboratory trials conducted in 30-gal (~136 L) glass tanks, using one cunner per infected salmon, a significant reduction in sea lice numbers was evident. In seapen trials using 30 cunner to 2000 Atlantic salmon, no significant reduction in sea lice numbers was evident after 12 weeks. Availability of fouling organisms on the seapen net may account, in part, for the lack of cleaning behaviour in these fish.

scholarly journals Infectious disease outbreaks in the African region: overview of events reported to the World Health Organization in 2018

2019 ◽  
Vol 147 ◽  
Author(s):  
F. Mboussou ◽  
P. Ndumbi ◽  
R. Ngom ◽  
Z. Kassamali ◽  
O. Ogundiran ◽  
...  
Keyword(s):  
Infectious Disease ◽  
Disease Onset ◽  
Disease Outbreaks ◽  
Case Fatality ◽  
World Health ◽  
African Region ◽  
Regional Office ◽  
Member States ◽  
Infectious Disease Outbreaks ◽  
The World

Abstract The WHO African region is characterised by the largest infectious disease burden in the world. We conducted a retrospective descriptive analysis using records of all infectious disease outbreaks formally reported to the WHO in 2018 by Member States of the African region. We analysed the spatio-temporal distribution, the notification delay as well as the morbidity and mortality associated with these outbreaks. In 2018, 96 new disease outbreaks were reported across 36 of the 47 Member States. The most commonly reported disease outbreak was cholera which accounted for 20.8% (n = 20) of all events, followed by measles (n = 11, 11.5%) and Yellow fever (n = 7, 7.3%). About a quarter of the outbreaks (n = 23) were reported following signals detected through media monitoring conducted at the WHO regional office for Africa. The median delay between the disease onset and WHO notification was 16 days (range: 0–184). A total of 107 167 people were directly affected including 1221 deaths (mean case fatality ratio (CFR): 1.14% (95% confidence interval (CI) 1.07%–1.20%)). The highest CFR was observed for diseases targeted for eradication or elimination: 3.45% (95% CI 0.89%–10.45%). The African region remains prone to outbreaks of infectious diseases. It is therefore critical that Member States improve their capacities to rapidly detect, report and respond to public health events.

scholarly journals Impact of Nisin and Nisin-Producing Lactococcus lactis ssp. lactis on Clostridium tyrobutyricum and Bacterial Ecosystem of Cheese Matrices

Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 898
Author(s):  
Hebatoallah Hassan ◽  
Daniel St-Gelais ◽  
Ahmed Gomaa ◽  
Ismail Fliss
Keyword(s):  
Lactococcus Lactis ◽  
Cheddar Cheese ◽  
Economic Loss ◽  
Gas Production ◽  
Clostridium Tyrobutyricum ◽  
Nisin Production ◽  
Genus Clostridium ◽  
Milk Pasteurization ◽  
Cheese Slurry ◽  
Significant Economic Loss

Clostridium tyrobutyricum spores survive milk pasteurization and cause late blowing of cheeses and significant economic loss. The effectiveness of nisin-producing Lactococcus lactis ssp. lactis 32 as a protective strain for control the C. tyrobutyricum growth in Cheddar cheese slurry was compared to that of encapsulated nisin-A. The encapsulated nisin was more effective, with 1.0 log10 reductions of viable spores after one week at 30 °C and 4 °C. Spores were not detected for three weeks at 4 °C in cheese slurry made with 1.3% salt, or during week 2 with 2% salt. Gas production was observed after one week at 30 °C only in the control slurry made with 1.3% salt. In slurry made with the protective strain, the reduction in C. tyrobutyricum count was 0.6 log10 in the second week at 4 °C with both salt concentration. At 4 °C, nisin production started in week 2 and reached 97 µg/g after four weeks. Metabarcoding analysis targeting the sequencing of 16S rRNA revealed that the genus Lactococcus dominated for four weeks at 4 °C. In cheese slurry made with 2% salt, the relative abundance of the genus Clostridium decreased significantly in the presence of nisin or the protective strain. The results indicated that both strategies are able to control the growth of Clostridium development in Cheddar cheese slurries.

scholarly journals Rapid Multi-Hybridisation FISH Screening for Balanced Porcine Reciprocal Translocations Suggests a Much Higher Abnormality Rate Than Previously Appreciated

Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 250
Author(s):  
Rebecca E O’Connor ◽  
Lucas G Kiazim ◽  
Claudia C Rathje ◽  
Rebecca L Jennings ◽  
Darren K Griffin
Keyword(s):  
Semen Analysis ◽  
In Situ Hybridisation ◽  
Economic Loss ◽  
Environmental Damage ◽  
Fluorescence In Situ Hybridisation ◽  
Reciprocal Translocations ◽  
Chromosome Translocations ◽  
Farrowing Rate ◽  
Significant Economic Loss

With demand rising, pigs are the world’s leading source of meat protein; however significant economic loss and environmental damage can be incurred if boars used for artificial insemination (AI) are hypoprolific (sub-fertile). Growing evidence suggests that semen analysis is an unreliable tool for diagnosing hypoprolificacy, with litter size and farrowing rate being more applicable. Once such data are available, however, any affected boar will have been in service for some time, with significant financial and environmental losses incurred. Reciprocal translocations (RTs) are the leading cause of porcine hypoprolificacy, reportedly present in 0.47% of AI boars. Traditional standard karyotyping, however, relies on animal specific expertise and does not detect more subtle (cryptic) translocations. Previously, we reported development of a multiple hybridisation fluorescence in situ hybridisation (FISH) strategy; here, we report on its use in 1641 AI boars. A total of 15 different RTs were identified in 69 boars, with four further animals XX/XY chimeric. Therefore, 4.5% had a chromosome abnormality (4.2% with an RT), a 0.88% incidence. Revisiting cases with both karyotype and FISH information, we reanalysed captured images, asking whether the translocation was detectable by karyotyping alone. The results suggest that chromosome translocations in boars may be significantly under-reported, thereby highlighting the need for pre-emptive screening by this method before a boar enters a breeding programme.

scholarly journals Antimicrobial Activity of Chitosan Oligosaccharides with Special Attention to Antiparasitic Potential

Marine Drugs ◽  
2021 ◽  
Vol 19 (2) ◽  
pp. 110
Author(s):  
Nayara Sousa da Silva ◽  
Nathália Kelly Araújo ◽  
Alessandra Daniele-Silva ◽  
Johny Wysllas de Freitas Oliveira ◽  
Júlia Maria de Medeiros ◽  
...  
Keyword(s):  
Disease Outbreaks ◽  
Biological Properties ◽  
Enzymatic Production ◽  
Infectious Disease Outbreaks ◽  
Chitosan Oligosaccharides ◽  
Lower Viscosity ◽  
Biomedical Industry ◽  
Parasite Aggregation ◽  
Hydrolysis Of

The global rise of infectious disease outbreaks and the progression of microbial resistance reinforce the importance of researching new biomolecules. Obtained from the hydrolysis of chitosan, chitooligosaccharides (COSs) have demonstrated several biological properties, including antimicrobial, and greater advantage over chitosan due to their higher solubility and lower viscosity. Despite the evidence of the biotechnological potential of COSs, their effects on trypanosomatids are still scarce. The objectives of this study were the enzymatic production, characterization, and in vitro evaluation of the cytotoxic, antibacterial, antifungal, and antiparasitic effects of COSs. NMR and mass spectrometry analyses indicated the presence of a mixture with 81% deacetylated COS and acetylated hexamers. COSs demonstrated no evidence of cytotoxicity upon 2 mg/mL. In addition, COSs showed interesting activity against bacteria and yeasts and a time-dependent parasitic inhibition. Scanning electron microscopy images indicated a parasite aggregation ability of COSs. Thus, the broad biological effect of COSs makes them a promising molecule for the biomedical industry.

scholarly journals Genome-scale comparative analysis for host resistance against sea lice between Atlantic salmon and rainbow trout

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pablo Cáceres ◽  
Agustín Barría ◽  
Kris A. Christensen ◽  
Liane N. Bassini ◽  
Katharina Correa ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Atlantic Salmon ◽  
Candidate Genes ◽  
Protein Phosphatase ◽  
Sea Lice ◽  
Genome Wide Association Studies ◽  
Dual Specificity ◽  
Dual Specificity Protein Phosphatase ◽  
Genomic Regions ◽  
Specificity Protein

AbstractSea lice (Caligus rogercresseyi) is an ectoparasite which causes major production losses in the salmon aquaculture industry worldwide. Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) are two of the most susceptible salmonid species to sea lice infestation. The objectives of this study were to: (1) identify genomic regions associated with resistance to Caligus rogercresseyi in Atlantic salmon and rainbow trout by performing single-step Genome-Wide Association studies (ssGWAS), and (2) identify candidate genes related to trait variation based on exploring orthologous genes within the associated regions across species. A total of 2626 Atlantic salmon and 2643 rainbow trout were challenged and genotyped with 50 K and 57 K SNP panels, respectively. We ran two independent ssGWAS for sea lice resistance on each species and identified 7 and 13 regions explaining more than 1% of the genetic variance for the trait, with the most important regions explaining 3% and 2.7% for Atlantic salmon and rainbow trout, respectively. We identified genes associated with immune response, cytoskeleton function, and cell migration when focusing on important genomic regions for each species. Moreover, we found 15 common orthogroups which were present in more than one associated genomic region, within- or between-species; however, only one orthogroup showed a clear potential biological relevance in the response against sea lice. For instance, dual-specificity protein phosphatase 10-like (dusp10) and dual-specificity protein phosphatase 8 (dusp8) were found in genomic regions associated with lice density in Atlantic salmon and rainbow trout, respectively. Dusp10 and dusp8 are modulators of the MAPK pathway and might be involved in the differences of the inflammation response between lice resistant and susceptible fish from both species. Our results provide further knowledge on candidate genes related to sea lice resistance and may help establish better control for sea lice in fish populations.

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