Feline testicular ultrasonogram differentiates pre vs. postpubertal and normal vs. disrupted spermatogenesis

Area of Science:

• Veterinary Medicine
• Reproductive Biology
• Medical Imaging

Background:

• Assessing feline reproductive maturity and health typically involves invasive methods.
• Objective, quantitative evaluation of testicular parenchyma is crucial for understanding spermatogenesis.
• Digital image analysis offers a potential non-invasive tool for testicular assessment.

Purpose of the Study:

• To ultrasonographically describe and compare testicular parenchyma echogenicity and heterogeneity in prepubertal, peripubertal, and mature cats.
• To evaluate these parameters in normal and abnormal mature felids.
• To correlate ultrasonographic findings with histomorphological testicular attributes.

Main Methods:

• Digital image analysis of B-mode ultrasonograms from longitudinal testicular sections.
• Selection of three regions of interest (1 mm²) within the parenchyma for analysis.
• Measurement of testicular volume, gonadosomatic index, echogenicity, and heterogeneity.
• Histomorphometric assessment of testes, including seminiferous tubular diameter and cell type percentages.

Main Results:

• Testicular volume, echogenicity, and heterogeneity increased significantly with age from prepubertal to mature cats.
• In abnormal mature testes, administration of a GnRH antagonist led to decreased testicular volume and echogenicity.
• Strong correlations were found between testicular volume, seminiferous tubular diameter, spermatid percentage, luminal/intertubular ratio, and echotextural attributes.

Conclusions:

• Computer-assisted analysis of B-mode ultrasonograms is a valuable tool for assessing pubertal development in cats.
• This imaging technique can detect mild alterations in spermatogenesis in felids.
• Ultrasonographic echotextural attributes correlate well with key histomorphological indicators of testicular function.