Rebecca Lawson Position/Title: MSc Thesis Candidate email: rlawso02@uoguelph.ca Phone: Office: ANNU 116 Research Gate LinkedIn Twitter

I grew up in Toronto, ON and I graduated with a BSc in Marine Biology and Certificate in Aquaculture from Dalhousie University in Halifax, NS in May 2020. In January 2021, I started my MSc by Thesis in Animal Nutrition at the University of Guelph with Dr. David Huyben investigating the effects of different dietary components on the growth and gut microbiome of lake whitefish (Coregonus clupeaformis).

My MSc research project will investigate the effects of dietary fat to protein ratios, and black soldier fly (BSF) insect meal on the growth and gut microbiota of lake whitefish. Lake whitefish are a common commercial and Indigenous fisheries species, however its presence in the aquaculture industry is limited. The findings from my research could help make an optimized feed for whitefish which is fundamental to the success of farming this species. In addition, the use of insect meal as a sustainable protein source in aquaculture feeds has been of increasing interest because they can be grown using compost or other by-products and provide beneficial compounds that may improve fish health.

I hypothesize that the growth of whitefish will increase when fed a lower fat to protein ratio diet because it will better fulfill their nutritional requirements. In addition, I hypothesize that fish growth will also increase when fed a diet that includes insect meal, due to the beneficial compounds it provides, which may diversify the gut microbiome. To test these hypotheses, I conducted a four-month growth trial using four experimental diets and one commercial made trout feed as a control. I expect to see differences in average fish growth and gut microbiota composition between diets. I predict the fish fed the low fat – high protein diets will have the most growth by the end of the trial. I also predict that the fish fed diets containing BSF meal will have a higher diversity of gut microbiota. The growth trial ended on October 26^th, 2021, next I will analyse the gut microbiota and conduct nutritional analyses. I will also be conducting a meta-analysis to rank the factors that affect the gut bacteria in salmonids.

The results from my MSc research project will provide novel information on the nutritional requirements and gut microbiota of lake whitefish which is essential for developing an optimized diet for the species. Having an optimized feed is fundamental for successfully incorporating lake whitefish into the Ontario aquaculture industry.