Swain, J. K. | Search bioRxiv

bioRxiv2023

Production of sterile Atlantic salmon by germ cell ablation with antisense oligonucleotides

Cultivation of sterile-only fish in aquaculture offers multiple benefits of environmental, economical, and social value. A reliable method for efficient sterilization without affecting fish welfare and performance traits would have significant impact on fish production practices. Here, we demonstrate sterilization of Atlantic salmon embryos by targeting the dead end gene with antisense oligonucleotides. Successful gene knock down and sterilization was achieved only when using Gapmer oligonucleotides and not with morpholino oligos. Germ cell-depleted embryos developed into morphologically normal male and female salmon with rudimentary gonads devoid of gametes.

developmental biology↗

bioRxiv2020

Effectiveness of fusion peptide-based vaccine TT-P0 on the dynamics of salmon lice (Lepeophtheirus salmonis) infection in Atlantic salmon (Salmo salar L.)

Infection with parasitic copepod salmon louse Lepeophtheirus salmonis, represents one of the most important limitations to sustainable Atlantic salmon (Salmo salar L.) farming today in the North Atlantic region. The parasite exerts negative impact on health, growth and welfare of farmed fish as well as impact on wild salmonid populations. It is therefore central to ensure continuous low level of salmon lice with the least possible handling of the salmon and drug use. To address this, vaccination is a cost-effective and environmentally friendly control approach. In this study, efficacy of a vaccine candidate, containing a peptide derived from ribosomal protein P0, was validated post infestation with L. salmonis, at the lab-scale. The sampling results showed good potential of the vaccine candidate when administered intraperitoneally in the host, in reducing the ectoparasite load, through reduction of adult female lice counts and fecundity and with greater presumptive effect in F1 lice generation. The sampling results correlated well with the differential modulation of pro-inflammatory, Th1, Th2 and T regulatory mediators at the transcript level at different lice stages. Overall, the results supports the effectiveness of the vaccine candidate in controlling salmon lice infestation load. However, further validation is necessary under field conditions.

immunology↗