# Interdisciplinary Tools to Safeguard and Amplify Aquatic Genetic Resource Use: A Foundation for Industrial-Scale Quality Control for Fertilization

## TL;DR

This paper introduces a quality control framework using a 'fertilization unit' to improve the efficiency of aquatic species breeding by standardizing sperm use during spawning.

## Contribution

The study introduces a novel quality control framework using a 'fertilization unit' to standardize sperm use in aquatic species breeding.

## Key findings

- Using the fertilization unit decreased 'wasted' sperm and reduced variability during spawning.
- Fertilization efficiency dropped significantly when sperm use deviated from the fertilization unit, especially in oysters and catfish.
- Reproductive strategy and production setting significantly influence the fertilization unit.

## Abstract

Standardized management of the physical genetic material (i.e., sperm or egg cells) of aquatic species is becoming increasingly important for industries such as aquaculture and biomedical research. These industries often develop animals with valuable traits through selective breeding, and protecting these gains requires careful management of genetic material. This study provides a quality control framework for using a consistent amount of sperm when spawning to increase the consistency and efficiency of breeding efforts for aquatic species. Blue catfish, zebrafish, and eastern oysters were used as example species. The quality control framework provided in this study included a formula to calculate the “fertilization unit,” or the amount of sperm required to reliably fertilize the eggs produced by a female. We concluded that using the fertilization unit decreased “wasted” sperm and reduced variability during spawning. Adopting this kind of quality control framework will support more efficient breeding, better business planning, and improved use of valuable genetic resources in aquaculture and aquatic industries.

Genetic resources are becoming increasingly important in aquatic species, especially in sectors such as aquaculture and biomedical research. These advancements, however, lack standardized methodology to consistently improve efficient use of gametes for fertilization and to eliminate male variation during spawning. This study provides a conceptual basis for generalizable quality control in artificial spawning of aquatic species by using interdisciplinary, industrial-scale tools to calculate a fertilization unit (e.g., the amount of sperm required to reliably fertilize the eggs produced by a female). Blue catfish (Ictalurus furcatus), zebrafish (Danio rerio), and eastern oysters (Crassostrea virginica) were used as diverse representative species. Comparisons among aquatic species were reviewed, fertilization units were defined, and a sensitivity analysis was performed to assess how deviations from the fertilization unit could affect artificial spawning efficiency. Overall, reproductive strategy (e.g., gamete biology) and production setting significantly influenced the fertilization unit. Employing a fertilization unit decreased “wasted” sperm and reduced male variability during spawning. Furthermore, fertilization efficiency dropped significantly when sperm use strayed from the fertilization unit, declining with both underuse and overuse, especially in oysters and catfish. Standardizing gamete use in aquatic species is essential for economic planning and achieving commercial-scale production, especially when investing in selectively bred or cryopreserved sperm.