Within Europe over the last 10 years, there has been an increase in seaweeds cultivated for human consumption. For food safety reasons, it is important to assess the microbiological and nutritional quality of the biomass. The fresh and dried edible seaweeds Alaria esculenta and Saccharina latissima were assessed over two consecutive years for the presence of microorganisms. Seaweed samples supplied from Scotland were stored under isothermal conditions for specific time intervals depending on the sample’s condition (fresh, dried or rehydrated). During storage, microbiological analyses were performed for the enumeration of Total Viable Counts (TVC), Pseudomonas spp., Enterobacteriaceae and Bacillus spp., as well as yeasts and molds. Additionally, bacterial colonies from the Marine Agar growth medium were isolated and subjected to PCR-RAPD analysis for characterization of the bacterial diversity of seaweeds. Bacterial isolates with different fingerprint patterns were further subjected to sequencing (16S rDNA, V1–V4 region). The presence of human pathogenic bacteria was also investigated. Results showed that the initial population of TVC was differentiated depending on the year of seaweed harvest, being closer to the enumeration limit (1.0 log CFU/g) in fresh samples from 2020 and higher in samples from 2019 (6.7 and 3.9 log CFU/g in A. esculenta and S. latissima, respectively). DNA-based analysis revealed the presence of Psychrobacter, Cobetia and Pseudomonas species in A. esculenta, while Psychrobacter and Micrococcus species were present in S. latissima.
Mussels belonging to the Mytilus species complex (M. edulis, ME; M. galloprovincialis, MG; and M. trossulus, MT) often occur in sympatry, facilitating introgressive hybridisation. This may be further promoted by mussel aquaculture practices, with MT introgression often resulting in commercially unfavourable traits such as low meat yield and weak shells. To investigate the relationship between genotype and shell phenotype, genetic and morphological variability were quantified across depth (1 m to 7 m) along a cultivation rope at a mussel farm on the West coast of Scotland. A single nuclear marker (Me15/16) and a novel panel of 33 MT‐diagnostic single nucleotide polymorphisms were used to evaluate stock structure and the extent of MT introgression across depth. Variation in shell strength, determined as the maximum compression force for shell puncture, and shell shape using geometric morphometric analysis, were evaluated in relation to cultivation depth and the genetic profiles of the mussels. Overall, ME was the dominant genotype across depth, followed by ME x MG hybrids and smaller quantities of ME x MT hybrids and pure MT individuals. In parallel, we identified multiple individuals that were either predominantly homozygous or heterozygous for MT‒diagnostic alleles, likely representing pure MT and first generation ME x MT hybrids, respectively. Both the proportion of individuals carrying MT alleles and MT allele frequency declined with depth. Furthermore, MT‐introgressed individuals had significantly weaker and more elongate shells than non‐introgressed individuals. This study provides detailed insights into stock structure along a cultivation rope and suggests that practical methods to assess shell strength and shape of cultivated mussels may facilitate the rapid identification of MT, limiting the impact of this commercially damaging species.
Farming has been changing through multiple technological transformations in recent years, in parallel with the earth’s growing population and demands. The Internet of Things (IoT) provides very remarkable technological innovations on farming by bringing a new paradigm. Aquaculture in fresh or salt water is a rapidly growing food sector to produce aquatic plants or animals. IoT can also produce encouraging solutions for the problems in the implementation and maintenance of aquaculture systems. In this paper, we present a use case with an IoT cloud solution after summarizing the potential technologies and tools to use in accordance with the use case problem as identified in the Horizon2020 Project, the intelligent management system for integrated multi-trophic aquaculture (IMPAQT) in which we have been participating in.