Lack of Relationship between Testicular Echotexture and Seminal Characteristics in Adult Texel Rams

Abstract

The objective of this study was to determine the minimum representative area to evaluate testicular echotexture parenchyma and to identify the correlations between the intensity of pixels of the testicular parenchyma and the fibrosis score with the physical and morphological characteristics of the ejaculate of Texel rams. The study used 88 Texel rams, aged between 10 and 12 months, and reared in a semi-extensive system. The animals underwent breeding soundness evaluation (BSE) and ultrasound of the testicles. The images were transferred to a computer where they were defined in areas of 400, 1600, 3600, and 6400 mm 2 , after which the average intensity of the pixels of each image of the testicular regions was evaluated. A testicular fibrosis score was assigned in order to quantify the frequency of fibrotic lesions. In relation to the intensity of pixels of the predetermined regions, only the area of 400 mm 2 presented a difference (P < 0.05), with the area of 1600 mm 2 being the smallest area that best represented the testicular parenchyma. There were no correlations between the intensity of pixels of the testicular parenchyma and the fibrosis score with the physical and morphological characteristics of the ejaculate of the rams.

Biometric Indicators, Testicular Parameters and Semen Characteristics in Peripubertal and Postpubertal Pleven Blackhead Rams

“…A testicular echogenicity varying highly with age, associated with an initial increase followed by a decline, corresponding to the mitotic and postmitotic phases of spermatogenesis in prepubescent ram lambs was reported by Giffin et al (2014). Urt et al (2018) related the differences in testicular parenchymal echogenicity to the stage of sexual maturity of the rams studied (end of puberty and beginning of sexual maturity) and the anatomical changes of the seminiferous tubules. Camela et al (2019) accepted that the difference in testicular echotexture was due to changes of the testes' histomorphology occurring at puberty and explaining the decline in both echotextural variables with seminiferous tubule area differentiation, manifesting in the presence of more mature germ cells in the majority of seminiferous tubules.…”

“…Regarding the intensity of the pixels of the predetermined regions and the testes position, Urt et al (2018) observed a difference between left and right testes when testicular parenchyma with area of 400 mm 2 was examined. Because of that, they recommended average intensity of the pixels of the left and right testes of the 1600 mm 2 area (40 x 40 mm) for correct echotexture analysis.…”

“…February 2020 | Volume 8 | Issue 2 | Page 219 measured and their means were accepted as final values for each testis (Urt et al, 2018). A total testicular parenchymal echogenicity (TTPE) and total pixel heterogeneity (TPH) were given as mean values and standard deviations after their measurement in both testes of the same animal.…”

“…An ultrasonographic image is composed of pixels, and numerical pixel values and standard deviation of numerical pixel values are directly connected with tissues characteristics (Pirson and Adams, 1995;Chandolia et al, 1997). The determination of NPVs and standard deviation of NPVs by computer-assisted image analysis allows measurement of the tissues echotexture in a very objective way, imperceptible to the human eye (Singh et al, 2003;Giffin et al, 2009;Urt et al, 2018). Comparing mean echogenicity and pixel heterogeneity values in the different groups, no differences between the mean values for left and right testes were observed.…”

Testicular Ultrasound Analysis as a Predictive Tool of Ram Sperm Quality

“…These range from 0 (absolute black) to 255 (absolute white) and provide an indication of tissue echogenicity [ 14 ]. Thereby, ultrasound analysis has been used to predict the reproductive soundness of rams [ 15 , 16 , 17 ] or the detection of pubertal changes in lambs [ 18 , 19 ]. However, in these previous studies, the ultrasound images were evaluated by non-specific image-analysis software (such as Image ProPlus ® or Image J), which could decrease the sensitivity and reproducibility of the results.…”