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2023 Acuerdos transformativos CRUE, Lactococcosis is a globally prevalent infectious disease that has a significant economic and sanitary impact on the rainbow trout industry. Lactococcus garvieae has traditionally been considered the only species implicated in the etiology of this disease, but Lactococcus petauri, a new species, has recently been implicated as another etiological agent. Both species cannot be distinguished by routine methods commonly used in diagnostic laboratories, resulting in their misidentification. In the present study, the identification of 48 isolates initially identified as L. garvieae was studied by determining their in-silico DNA–DNA hybridization (dDDH) and average nucleotide identity (ANI) values using pairwise comparisons of their whole genome sequences and the genomes of the type strains of L. garvieae and L. petauri. The genome sequences of 37 isolates from countries in which lactococcosis can be considered endemic (Spain, Italy, Türkiye, and Greece) were obtained in this study, and the genomes of 11 isolates were retrieved from the GenBank database. Isolates from Italy, Singapore, Japan, South Korea, India, one Turkish isolate from 2013 and two Spanish isolates recovered in 1992 and 1996 were confirmed as L. garvieae. The remaining isolates from Spain and Türkiye, as well as those from Portugal, Israel, USA, and Greece were identified as L. petauri. Overall, 60.4% of isolates previously identified as L. garvieae were found to be L. petauri. These results confirm the implication of both species in the etiology of lactococcosis and suggest that L. petauri plays a significant role in the epidemiology of this disease. Some of the isolates identified as L. petauri in the present study were isolated three decades ago, indicating that its association with lactococcosis is older than might be expected from the recent descriptions. The commercial Rapid ID32 Strep system was unable to discriminate between L. garvieae and L. petauri. However, both species exhibited some biochemi, Depto. de Sanidad Animal, Fac. de Veterinaria, Centro de Vigilancia Sanitaria Veterinaria (VISAVET), TRUE, pub, APC financiada por la UCM

AU T H O R CO N T R I B U T I O N S: All authors have confirmed to submit the manuscript. DATA AVA I L A B I L I T Y S TAT E M E N T: The data that support the findings of this study are available fromthe corresponding author upon reasonable request., Lactococcosis, caused by the Gram-positive bacterium Lactococcus garvieae, is a major concern in rainbow trout (Oncorhynchus mykiss) farms, which are regularly affected by outbreaks especially during the summer/fall months. In these farms, unvaccinated healthy and symptomatic fish can coexist with vaccinated fish. In the present study, innate (leukogram, serum lysozyme activity, peroxidase activity, antiprotease activity, bactericidal activity, total IgM and total proteins), and specific immune parameters (serum antibodies to L. garvieae) were assessed in unvaccinated adult rainbow trout naturally exposed to the pathogen, with or without evidence of clinical signs, or subjected to vaccination. Blood was drawn from all three groups, and blood smears were prepared. Bacteria were found in the blood smears of 70% of the symptomatic fish but not in any of the asymptomatic fish. Symptomatic fish showed lower blood lymphocytes and higher thrombocytes than asymptomatic fish (p ≤ .05). Serum lysozyme and bactericidal activity did not vary substantially among groups; however, serum antiprotease and peroxidase activity were significantly lower in the unvaccinated symptomatic group than in the unvaccinated and vaccinated asymptomatic groups (p ≤ .05). Serum total proteins and total immunoglobulin (IgM) levels in vaccinated asymptomatic rainbow trout were significantly higher than in unvaccinated asymptomatic and symptomatic groups (p ≤ .05). Similarly, vaccinated asymptomatic fish produced more specific IgM against L. garvieae than unvaccinated asymptomatic and symptomatic fish (p ≤ .05). This preliminary study provides basic knowledge on the immunological relationship occurring between the rainbow trout and L. garvieae, potentially predicting health outcomes. The approach we proposed could facilitate infield diagnostics, and several non-specific immunological markers could serve as reliable indicators of the trout's innate ability to fight infection., University of Udine, Depto. de Sanidad Animal, Centro de Vigilancia Sanitaria Veterinaria (VISAVET), TRUE, pub

The conservation of biodiversity from the genetic to the community levels is fundamental for the continual provision of ecosystem services (ES), the benefits that ecosystems provide to people. Genetic and genomic diversity enhance the resilience of populations and communities that underpin the provision of ecosystem functions and services. We show that genomics applications are mostly limited to flagship species and that their benefits for biodiversity conservation and ES management are underachieved. We propose a framework on how genomics applications can guide management for biodiversity conservation and sustainable ES to bridge this genomics-ES management ‘application gap’. We review how genomic knowledge in single species (relatedness, potentially adaptive variants) or in interacting species (host-microorganism coevolution, hybridization) can guide effective management actions. These include population supplementation, assisted migration or hybridization to promote climate-adapted variants or adaptive potential, control of invasives, delimitation of conservation or management areas, provenancing strategies for restoration, managing microbial function and solving conservation and ES trade-offs. Genomics-informed management actions for improved conservation and ES outcomes are supported through synergies between scientists and ES managers at local, regional and international levels, through the development of standardized genomic workflows, training to ES managers and incorporation of local information. Such actions facilitate the implementation of biodiversity conservation and ES policies such as the UN 2030 sustainable development goals and the EU Biodiversity strategy for 2030, and support the inclusion of ambitious biodiversity conservation goals in the development of new policies such as the CBD post-2020 Global Biodiversity Framework or conservation policies on hybrids.