Application of ultrasound technique to evaluate the testicular function and its correlation to the sperm quality after different collection frequency in rams

Rafael Montes-Garrido; Marta F Riesco; Luis Anel-Lopez; Marta Neila-Montero; Cristina Palacin-Martinez; Juan Carlos Boixo; Paulino de Paz; Cristina Ortega-Ferrusola; Mohamed A A Hassan; Luis Anel; Mercedes Alvarez

doi:10.3389/fvets.2022.1035036

Application of ultrasound technique to evaluate the testicular function and its correlation to the sperm quality after different collection frequency in rams

Front Vet Sci. 2022 Nov 25:9:1035036. doi: 10.3389/fvets.2022.1035036. eCollection 2022.

Authors

Rafael Montes-Garrido^{1

2}, Marta F Riesco^{1

3}, Luis Anel-Lopez^{1

4}, Marta Neila-Montero^{1

2}, Cristina Palacin-Martinez^{1

2}, Juan Carlos Boixo^{1

2}, Paulino de Paz^{1

3}, Cristina Ortega-Ferrusola⁵, Mohamed A A Hassan⁶, Luis Anel^{1

2}, Mercedes Alvarez^{1

2}

Affiliations

¹ Investigación en Técnicas de Reproducción Asistida - Universidad de León, Instituto de Desarrollo Ganadero y Sanidad Animal, University of León, León, Spain.
² Animal Reproduction and Obstetrics, Department of Veterinary Medicine, Surgery and Anatomy, University of León, León, Spain.
³ Celular Biology, Department of Molecular Biology, University of León, León, Spain.
⁴ Anatomy, Department of Veterinary Medicine, Surgery and Anatomy, University of León, León, Spain.
⁵ Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain.
⁶ Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Sohag University, Sohag, Egypt.

Abstract

The frequency of semen collection is a crucial factor to consider in the rams performance inside breeding centers workout. To evaluate this factor, ram Breeding Soundness Evaluation could include sperm quality evaluation and new predictive and non-invasive tools such as ultrasound technique. In this work, an advanced ultrasonography technology, analyzing the testicular volume, echotexture, and vascular function, was used in three different frequencies of semen collection (abstinence frequency, AF; standard frequency, SF; and intensive frequency, IF). Semen samples were cooled (15°C, 6 h) and evaluated in terms of production, motility, viability, apoptosis, and content of reactive oxygen species. Correlation coefficients were calculated between ultrasonography measurements of echotexture and blood flow and sperm quality parameters. Our results showed an increase in the testicular echotexture when the frequency of semen collection was intensified. Doppler parameters (PSV, RI, PI, TABF) increased (P ≤ 0.05) when the frequency of semen collection was intensified. The sperm motility and functionality decreased in the samples of IF (P ≤ 0.05), evidencing the frequency of semen collection's influence. Moreover, moderate positive correlations were established among echotexture and different Doppler parameters with motility parameters in SF. Furthermore, the influence of abstinence days on AI success was analyzed in a field assay. The highest fertility rates were obtained when males had two to five abstinence days. To conclude, frequency of semen collection could be influenced in terms of semen quantity and sperm quality, showing changes in parenchyma echotexture and testicular vascularization. The standard semen collection frequency was the most adequate option. In addition, ultrasonography may be a predictive tool for estimating variations in the sperm quality of donor rams subjected to different frequencies of semen collection in reproduction centers.

Keywords: Doppler; fertility; ovine; semen collection frequency; sperm quality; ultrasonography.