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This study aimed to evaluate the natural infection by SaV in pigs of different categories of production cycle in an important Brazilian pig-producing region. Faecal samples (n = 169) of suckling, post-weaning, finisher and breeder pig categories were analysed. Animals were from five farrow-to-weaning and nine grower-to-finish commercial pig farms. The RT-PCR assay was performed targeting the partial RNA-dependent RNA polymerase (RdRp) gene of porcine SaV genome. The virus was detected in 23.7% (40/169) of faecal samples and in 10/14 (5/5 farrow-to-weaning; 5/9 grower-to-finish) of pig farms evaluated. Porcine SaV was most frequently (p < 0.05) detected in pigs at post-weaning than in grower-to-finish and breeder categories. The phylogenetic analysis revealed that the porcine SaV strains belong to the GIII and GIX? genogroups. This study showed that the porcine SaV GIII genogroup has spread in the pig herds and provides the first evidence of GIX? genogroup circulation in South America.

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Palinurids, also known as spiny lobsters, are high‐value seafood, which is economically important for many European and Asian seafood trades. However, the reduction of wild European spiny lobster populations produces a need for developing alternative renewable strategies to meet current and future demands. Aquaculture of spiny lobsters has the potential to become of major economic importance in the coming years with growing markets in Asia, Europe, and America, with Palinurus elephas being a promising candidate species for use in the commercial culture and stock enhancement of natural fisheries. This is due to its shorter larval periods and rapid growth to the critical puerulus stage compared with other spiny lobster species. While we have a basic understanding of the lifecycle and biology of P. elephas, much of this is based on work undertaken on similar species globally. There are many gaps in our knowledge that need to be addressed to make its aquaculture viable with appropriate feeds being an immediate issue as well as many other husbandry‐related factors. Previous studies act as a platform providing a baseline for further research and highlighting constraints. Developments in the use of P. elephas are promising due to realistically bridgeable knowledge gaps, the likelihood of producing sustainable food and the high commercial value of spiny lobsters. This review identifies our present state of knowledge and outlines the scope for further research and necessary technological developments to make it a viable contribution towards crustacean aquaculture in Europe.

Several eco‐friendly natural substances can enhance the shrimp immune defence system therby acting as a prophylactic agent in feed additives. Agents such as (1, 3)‐(1, 6)‐D β‐glucan and complex mannan‐oligosaccharides located in yeast cell walls present such immunomodulatory and potential prebiotic properties. The aim of our study was to evaluate the effect of a commercial yeast cell wall extract (YCW) on shrimp performance and health status, and influence on gut microbiota. Juvenile Penaeus vannamei (Boone, 1931) were raised at an intensive shrimp farm and fed with two different diet inclusions levels of YCW, that is, 0.5% and 1.0%, in addition to a yeast free control group. After 102 days, animals were sampled, and standard nutrition performance parameters were measured. Additionally, the phylogenetic profile and composition of shrimp gut microbiota were evaluated. Animal performance, including growth and survival, was significantly better on animals fed with YCW than the control group. Furthermore, beneficial bacteria phylotypes were stimulated by the presence of YCW, positively modulating the gut microbiota, with emphasis on 1.0% YCW treatment. Therefore, YCW can be regarded as a prophylactic functional agent in the intensive rearing of juvenile P. vannamei thus improving animal performance and contributing to a healthy intestinal microbiota.

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Increased food demand, reflecting a rising global human population, attaining 8 billion in 2022, has furthered the intensification of farmed aquatic animal production. Intensification practices can be resource demanding for micro and macronutrients, dedicated feeds, fossil fuels, chemotherapeutics, and water. Water replaces evaporative losses and may be used to dilute nutrient‐rich wastewater. As an alternative to wastewater discharge, biofloc technology (BFT) uses microbes to manage nutrient levels in production systems. A microbial community grown at high densities can assimilate waste metabolites for growth. This is promoted by increasing the carbon–nitrogen (C:N) ratio using a combination of aquafeed fed to the fish and an additional carbohydrate source, for example, starch, molasses, or bran. The microbial biomass offers a continuous and additional food source to the farmed animal, thus reducing the need for finished aquafeeds and lowering the feed conversion ratio. Although the approach relies on multiple interacting species, BFT can be deployed in relatively low technology settings. This review considers the basis of BFT and identifies areas for innovation and expansion. For example, control of light quantity and quality can influence the biofloc and hence the growth of cultured species. Research on biofloc aquaculture is dominated by studies using tilapia and shrimp, but the technology could be applied to other species, particularly species that are tolerant of biofloc conditions and not highly carnivorous. Biofloc may be a useful biosecurity tool for all or part of the life cycle, and meals made from dried biofloc may enhance the production of cultured species. The key benefits of BFT can potentially be seen in reduced water consumption, lower feed requirements, and improved fish health. This review differs from current review papers in proposing the use of a life cycle assessment in conjunction with BFT, which may be a useful tool for describing and communicating the relative benefits of biofloc systems and their wider environmental impact. This study will serve as a useful knowledge base of BFT information for students, researchers, and stakeholders alike, offering a central source of the main aspects around the culturing of biofloc, key parameters, common species used, areas of potential improvement, and a discussion on where the future of BFT may lie.