The winter season is a critical development stage for salmon juveniles, requiring careful monitoring. It is essential to ensure the right water temperature, sufficient oxygen levels, good water exchange, and appropriate feeding. Additionally, attention must be paid to fish density and overall health. These factors help salmon juveniles grow successfully, adapt to smoltification, and prepare for their release into rivers in the spring.
As part of the INTERREG project SPPwelfare, during the second project period, we conducted health monitoring of salmon juveniles and collected data for the development of the Fish Health Index Model (FHIM) at the BIOR Fish Hatchery “Pelči” in Latvia and the Žeimena Salmon Hatchery in Lithuania. Our monitoring confirmed optimal weight gain and condition of the juveniles, and we observed that changes in fish health are closely linked to compliance with welfare requirements.
Fish health and the development of sustainable aquaculture are key factors for effective fish farming. The Scientific Institute “BIOR” has successfully carried out the first studies on the impact of probiotics on the health and growth performance of Baltic salmon (Salmo salar), as well as on the bacteria present in the skin mucus and their antimicrobial resistance (AMR).
The first studies were conducted at BIOR’s “Pelči” fish hatchery in a flow-through system, aiming to assess the effects of probiotics on growth performance and physiological condition in Baltic salmon. Microbiological samples were analyzed before and after probiotic use to evaluate their potential impact on bacterial populations and AMR.
Key Findings:
✔ Improved growth performance – Probiotic supplementation promoted weight gain and improved the condition factor of the salmon.
✔ Positive impact on the bacterial composition in skin mucus – Probiotic use influenced microbiota composition and reduced the number of antimicrobial-resistant bacteria.
The results provide new insights into the potential application of probiotics in aquaculture, their ability to improve fish health and growth efficiency, and their role in reducing the need for antibiotics, contributing to the implementation of more environmentally friendly and sustainable aquaculture practices.
The first research findings were presented at the EIFAAC (European Inland Fisheries and Aquaculture Advisory Commission) Conference in Croatia in 2024, as well as at the “Aquaculture in the Baltic – Challenges and Opportunities” conference in Latvia in 2024, facilitating international knowledge exchange among European experts.
The project is implemented within the Interreg VI-A Latvia–Lithuania Programme 2021–2027. More information about the programme on the www.latlit.eu and the official website of the European Union www.europa.eu.
The project implementation period is from March 1, 2024 till February 28, 2026.
This project is co-financed by the European Union. Total project budget is 497 146.00 EUR, funding of European Regional Development Fund is 397 716.80 EUR. The total eligible project budget of the scientific institute “BIOR” is 293,000.00 EUR, where co-funding of European Regional Development Fund is 234 400.00 EUR and state co-financing is 20% (58,600.00 EUR).
This publication has been produced with the financial support of the European Union. Its contents are the sole responsibility of the Institute of Food safety, Animal Health and Environment “BIOR” and do not necessarily reflect the views of the European Union.
Information posted: February 20, 2025
Lejupes iela 3, Rīga, LV-1076, 
+371 67620513
