Use of grayscale histogram to assess testicular changes in ram caused by heat stress

Abstract

Because it detects discrete changes in tissue density, ultrasound allows an early diagnosis of physiologic changes, especially when dealing with subclinical changes. aimed to evaluate the use of quantitative analysis of the gray scale of ultrasound images of ovine testicles as a method for early diagnosis of testicular changes caused by heat stress. Testicles from ten ovine were insulated and then evaluated regarding echogenicity, echotexture, anatomical measurements, and seminal characteristics. Echogenicity was the first variable to show changes during the insulation period, as well as the first one to show evidence of regeneration of those changes. There was a correlation (p < 0.05) between echogenicity and sperm vigor, motility, and mass sperm motility, as well as a correlation (p < 0.05) between echotexture and motility. Echogenicity, motility, vigor, and mass sperm motility decreased (p < 0.05) within four days of testicular insulation, and there was no change (p > 0.05) in echotexture. Testicular measurements were only altered (p < 0.05) after insulation; however, the structural integrity of the seminiferous tubules was not altered. Echogenicity is an efficient ultrasound parameter for the early diagnosis of a testicular degenerative process as well as for the early diagnosis of its regeneration.