Clinical, cytogenetic and hormonal findings in a stallion with hypospadias–a case report.

The abstract details a case study on a Friesian stallion, three-years old, with an unusual and rare congenital abnormality called hypospadias. Despite this condition, the study found that the stallion’s plasma levels of estrogen sulfate and testosterone, as well as the number of chromosomes, were normal when compared to a healthy stallion.

Clinical Findings and Physical Examination

• The study focused on a Friesian stallion which was observed to have hypospadias, a rare congenital abnormality in stallions. It’s an abnormality where the urethral opening is not at the usual place but is on the underside of the penis.
• The stallion’s physical examination revealed abnormalities in the structure of the reproductive organ. These included a ventrocaudal deviation of the penis shaft and an incomplete glans penis. The urethral opening was 4 cm in length, slit-like and covered in a mucous membrane. From the ventral aspect of the anus, a short fold ended with a non-pigmented hairless area of skin.

Human Choriongonadotropin (hCG) Stimulation Test

• A Human Choriongonadotropin (hCG) stimulation test was performed on the stallion. hCG is a hormone that stimulates the production of testosterone and estrogen sulfate.
• The test resulted in an increase in the plasma levels of estrogen sulfate and testosterone, indicating the presence of functional testicular tissue. Interestingly, these hormones levels were similar to those of a normal stallion, suggesting that hypospadias did not affect hormone production in this case.

Cytogenetic findings and Histological evaluation

• The researchers also analyzed the karyogram — the visual representation of a specimen’s chromosomes — and found that the number of chromosomes was normal at 2n=64.
• Post castration, a histological evaluation of the testicular tissue was conducted and it was found to be unremarkable, meaning there were no abnormalities in the tissue’s microscopic structure.

Summary and Conclusion

• In conclusion, even though hypospadias is a rare congenital abnormality in stallions, the affected stallion in this study showed no functional abnormalities, as shown by the hCG stimulation test and chromosome analysis.
• While the case provided valuable insights, the cause of hypospadias in this stallion could not be elicited, suggesting more research needs to be done to further understand this rare condition in stallions.