# Manipulated Spawning Along With an Extension of the Atlantic Salmon Broodfish Feeding Period Affect the Vitamin C, E, D, and K Status of Broodfish, Eggs, and First-Feeding Fry

## TL;DR

This study examines how feeding periods and spawning times affect vitamin levels in Atlantic salmon broodfish, eggs, and fry.

## Contribution

The study reveals how vitamin C, E, D, and K levels are influenced by feeding duration and ovulation timing in salmon reproduction.

## Key findings

- Vitamin deposition increased with growth, with muscle storing the highest amounts.
- Ovulation time had a greater impact on vitamin status than feeding regime.
- Vitamin levels in both feeding regimes met requirements for broodfish and fry, but early and late eggs were of lower quality.

## Abstract

The optimum period for feeding a broodfish diet combined with manipulated ovulation time, has recently been investigated for egg production capacity, as well as egg and juvenile quality in Atlantic salmon. Here, we report the status of vitamins C, E, D, and K in fish from the same experiment to ensure requirements were met. Two-sea-winter female broodfish were followed through a 17-month growth period, a starvation period on-land until ovulation, and offspring until first-feeding. Throughout all periods, the impact of 9 vs. 17 months of broodfish feed, and early (November), normal (December), and late (February) ovulation on vitamin status was monitored. Vitamin deposition increased with growth, with muscle depositing the highest amounts due to its size. Once the gonads matured, vitamins E, K, and D were similar to muscle, while C was higher. Livers had the highest C, E, and K concentrations, while D was comparable across tissues. During starvation, body stores of C, K, and D declined, while E remained high. All studied vitamins except for C followed the general nutrient deposition profile in unfertilized eggs, increasing from early to late ovulation. K1 was depleted as menaquinone-4 rose, suggesting possible conversion in broodfish and offspring. Ovulation time affected vitamin status more than feeding regime. Vitamin C, E, and most likely K and D levels in both feeding regimes covered the requirements for broodfish and first-feeding fry, regardless of ovulation treatment. However, both early and late eggs and juveniles were of inferior quality, suggesting factors beyond the vitamins examined influenced reproductive outcomes.