Hermaphroditism in a Sprague-Dawley rat

Area of Science:

• Veterinary Pathology
• Developmental Biology
• Rodent Models

Background:

• Repeat-dose toxicity studies are crucial for drug safety evaluation.
• Sprague-Dawley rats are commonly used in preclinical research due to their well-characterized physiology.
• Spontaneous conditions in animal models require careful documentation and differentiation from drug-induced effects.

Observation:

• A 9-week-old Sprague-Dawley rat, presumed female, exhibited unilateral true hermaphroditism.
• This finding was identified during routine necropsy as part of a repeat-dose toxicity study.
• No adverse effects related to the study drug were observed in the animal.

Findings:

• Unilateral true hermaphroditism is a rare congenital anomaly in rats.
• The incidence of true hermaphroditism in rats is very low, with few reported cases in scientific literature.
• The observed case was spontaneous and not associated with the experimental treatment.

Implications:

• This case highlights the importance of thorough pathological examination in toxicity studies to identify incidental findings.
• Understanding the incidence and nature of spontaneous conditions is vital for accurate interpretation of toxicity data.
• Documentation of rare conditions contributes to the broader knowledge base of rodent reproductive biology and pathology.