A method for gender determination in newborn dark pigmented mice.

Area of Science:

• Animal Science
• Developmental Biology
• Genetics

Background:

• Accurate determination of neonatal mouse pup gender is essential for research.
• Traditional methods like anogenital distance measurement can be unreliable and difficult.
• A need exists for a more efficient and accurate sexing technique in early-stage mouse pups.

Purpose of the Study:

• To introduce and validate a novel, simple method for determining the sex of neonatal pigmented mice.
• To compare the efficacy of the new method against the conventional anogenital distance measurement.

Main Methods:

• Observation of a distinct pigment spot on the scrotum of male mouse pups from the first day of life.
• Comparison of the 'spot on' method's accuracy and efficiency with anogenital distance measurements.
• Focus on pigmented mouse strains where the scrotal pigment is visible.

Main Results:

• Male pigmented mouse pups exhibit a visible scrotal pigment spot from birth.
• Female pups lack this visible pigmentation in the anogenital region.
• The 'spot on' method proved more accurate and efficient than anogenital distance measurement for pigmented neonates.

Conclusions:

• The 'spot on' method provides a quick, easy, and reliable way to determine the gender of pigmented neonatal mice.
• This technique serves as a valuable adjunct to existing methods for sexing mouse pups.
• The visual identification of scrotal pigmentation enhances experimental efficiency in mouse studies.