Dietary supplementation of prebiotics and organic minerals to improve growth performance, gut health, immunity and genetics of rainbow trout subject to low, moderate and high temperatures

Lead Applicant: David Huyben

Research Priority: Competitive Production Systems

Program Type: Tier 1

Funding Cycle: 2024/2025

Research Centre: Ontario Aquaculture Research Centre

Research Summary: Climate change continues to increase water temperatures, resulting in lower feeding rates, heat stress, disease and reduced production of farmed fish in lake net-pens. This project will evaluate how the supplementation of prebiotic yeast and organic minerals affects growth, physiologic and genetic responses of rainbow trout across several water temperatures. First, we will perform a meta-analysis followed by three feeding trials that will determine the effects of feeding graded levels of prebiotics/minerals at 9C, feeding at 15C and 25C temperatures and family genetics at different life-stages. In each trial, we will evaluate growth performance, nutrient retention, gut health, stress and immunity. This project will also establish relationships between the host with phenotypic traits (growth and survival) and physiological biomarkers (microbes and cortisol). This research will support Ontario aquaculture by providing diet and breeding strategies to cope with negative impacts of increased water temperature on fish production and health.