Skin swabbing protocol to collect DNA samples from small-bodied fish species

Area of Science:

• * Animal models in scientific research
• * Molecular biology and genetics
• * Aquatic animal welfare

Background:

• * Fin clipping is the standard DNA sampling method for laboratory fish.
• * Fin clipping can negatively impact fish health, behavior, and data integrity.
• * There is a need for less invasive DNA collection techniques in fish research.

Purpose of the Study:

• * To adapt and validate a skin swabbing protocol for DNA collection from small laboratory fish.
• * To compare the impact of skin swabbing versus fin clipping on fish stress and behavior.
• * To assess the effect of DNA sampling method on data variability.

Main Methods:

• * Developed a protocol using rayon-tipped swabs to collect mucus from the flank of fish.
• * Applied the protocol to small-bodied fish species, including sticklebacks and zebrafish.
• * Measured stress axis activation, behavior, gene expression, and data variability.

Main Results:

• * Skin swabbing induced fewer changes in stress axis activation and behavior than fin clipping.
• * DNA samples from skin swabbing yielded less variable gene expression and behavior data.
• * The protocol does not require analgesics, anesthetics, or sharp instruments.

Conclusions:

• * Skin swabbing is a less invasive and effective alternative to fin clipping for fish DNA sampling.
• * This method improves animal welfare and reduces experimental data variability.
• * Reduced data variability may allow for smaller experimental group sizes, decreasing overall animal use.