OMB number: 4040-0019 expiration date: 02/28/2025 project abstract summary this project abstract summary form must be submitted or the application will be considered incomplete

This Cooperative Agreement award of $835,829 from the National Oceanic and Atmospheric Administration (NOAA) under the Sea Grant Support program (CFDA 11.417) is aimed at identifying beneficial bacteria that facilitate healthy lobster egg development and testing them against pathogens that cause mortality or morbidity in lobster embryos. The key objectives are to characterize the microbiome of lobster eggs, examine how microbiome shifts relate to egg mortality, and determine which microbes act as probiotics to promote healthy embryo development. The project will be conducted by the Virginia Institute of Marine Science from October 1, 2024 to September 30, 2026. The findings could lead to the development of probiotic applications to support healthy lobster egg production.

Ensure the project abstract field succinctly describes the project in plain language that the public can understand and use without the full proposal. Use 4,000 characters or less. Do not include personally identifiable, sensitive or proprietary information. Refer to agency instructions for any additional project abstract field requirements. If the application is funded, your project abstract information (as submitted) will be made available to public websites and/or databases including usaspending.GOV. Funding opportunity number NOAA-OAR-SG-2024-25871 cfda(S) 11.417 applicant name virginia institute of marine science descriptive title of applicant's project shifting interactions in the microbiomes of lobster eggs and their implications for lobster health project abstract EGG mortality is an overlooked issue for many crustacean species, including lobsters. Its causes and outcomes are often unknown, but during periods of high EGG mortality, IT can have population-level consequences. Our project is aimed at identifying beneficial bacteria that facilitate healthy EGG development and test them against pathogens that cause mortality or morbidity to lobster embryos. Our broader goal is to understand the role of microbiomes on lobsters from the perspective of lobster health and disease resistance. Our first objectives are to characterize what microbes are present on lobster eggs and where they come from. We, therefore, ask 1) what is the origin of the microbiome on lobster embryos, and 2) what are the maternal, paternal, and environmental contributions to the microbiome on the newly laid embryos? Because dead and dying eggs accrue in lobster clutches during development, our next objective is to examine EGG mortality in relation to shifting microbiomes; hence, we ask 3) how do the microbiomes on dead, dying, and developmentally delayed eggs differ in comparison to those on healthy eggs? That is, what microbial pathogens are associated with EGG mortality? Because we know that beneficial bacteria occur on lobster embryos, our last objective is 4) to determine which members of the microbiome are beneficial probionts. We plan to identify them by their production of antimicrobial secondary metabolites and then test them against known EGG pathogens (lagenidium callinectes, leucothrix mucor, and those isolated from dead and dying embryos in this study). We will do this directly using in vitro challenge experiments with live embryos and zone of inhibition studies with culture isolates. We will examine how these probionts benefit or facilitate the development of healthy embryos. We have isolated a small consortium of bacteria as candidate probionts. One of these, an aliivibrio species, appears to be a promising candidate for further study. Beneficial bacteria have been used in a number of applications in human and animal health; therefore, we will explore the feasibility of developing our findings for potential field applications to promote healthy EGG development in lobsters.