Genotypic data from: Lab-based evaluation of the reproductive performance of trojan (MYY) brook trout (Salvelinus fontinalis)

Evaluating the efficacy of the use of trojan male brook trout with two Y chromosomes (MYY) requires a better understanding of reproductive performance. We measured the reproductive performance of hatchery age-0 and age-1 MYY brook trout compared to hatchery XY males using laboratory crosses. Offspring of XY males had higher survival than offspring of age-1 MYY one day post-fertilization but not offspring of age-0 MYY. We found no detectable differences in survival from eyed-egg to the juvenile-fry stage. However, size-at-age differed, where offspring of age-0 MYY were 3.6% smaller in length and 25.2% smaller in weight than those of XY males. For crosses fertilized by both MYY and XY males, we found that a significantly higher proportion of offspring within families were sired by MYY versus XY males. These results show, under controlled conditions, evidence for possible fitness advantage for MYY under sperm competition, but a possible fitness disadvantage associated with early growth of ..., MYY brook trout were obtained as eyed-eggs from Hayspur Hatchery (Idaho) and reared at Abernathy Fish Technology Center. Females were assessed for ripeness weekly to determine when to begin spawning. Females that were considered ripe (eggs readily released when light pressure was applied to the abdomen) were then placed into a separate holding area to prepare for spawning. Before spawning, all three male fish (XY male, age-0 MYY, and age-1 MYY) to be used for each cross were anesthetized using MS-222, then weighed (g) and measured for fork length (mm). The female was euthanized using MS-222, wiped dry, and a ventral incision was made and all eggs were manually expelled into a colander to remove excess fluid. The overall weight (g) of the eggs was determined, and eggs were divided into four evenly weighted groups and placed into four large Petri dishes. Each group was then fertilized using milt from one male type: XY male (cross-type 1), age-0 MYY (cross-type 2), age-1 MYY (cross-type 3)..., , # Genotypic data from: Lab-based evaluation of the reproductive performance of trojan (MYY) brook trout (*Salvelinus fontinalis*)

[https://doi.org/10.5061/dryad.x3ffbg7rs](https://doi.org/10.5061/dryad.x3ffbg7rs)

Genotypic data of the offspring as well as potential parents (both male and female) for mixture crosses (Cross-type 4) spawned. Includes individual ID, female parent ID, percent of genotype that was successfully extracted, and 240 loci with 1 column per locus.

## Description of the data and file structure

Variables:

* FieldID1- unique individual identifier
* Age- Young-of-year (YOY) or adult
* sex- sex of adult (missing for YOY)
* Female #- the ID number of the female parent (missing for adult individuals)
* GenotypeSuccess- percent of genotype that was successfully extracted
* Columns F-IK - individual loci with 1 column per locus

Missing data =0

## Sharing/Access information

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## Code/Software

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