CURRENT TRENDS ON STALLION SEMEN EVALUATION: WHAT OTHER METHODS CAN BE USED TO IMPROVE OUR CAPACITY FOR SEMEN QUALITY ASSESSMENT?

Camilo Hernández-Avilés; Jorge Zambrano-Varón; Claudia Jiménez-Escobar

CURRENT TRENDS ON STALLION SEMEN EVALUATION: WHAT OTHER METHODS CAN BE USED TO IMPROVE OUR CAPACITY FOR SEMEN QUALITY ASSESSMENT?

Camilo Hernández-Avilés, Jorge Zambrano-Varón, Claudia Jiménez-Escobar

Resumen

ABSTRACT

Semen evaluation is an important component for the assessment of the stallion breeding potential, as well as for the diagnosis of subfertility/infertility cases. Furthermore, accurate estimation of the damage suffered by the sperm cell after cooling or freezing procedures is necessary for the development of newer procedures to maintain sperm integrity and function. Nevertheless, commonly used methods for sperm quality evaluation (sperm motility or sperm morphology) are not completely associated with the fertilizing potential of the spermatozoa under in vitro conditions, and in the best-case scenario are poor- to- moderately associated with in vivo fertility. In recent years, the introduction of advanced methods based on the use of fluorochromes for sperm evaluation has improved the clinician’s and researcher’s capacity to account for the differences on the fertility potential between sires, as well as critically evaluate the effect of several methods to preserve stallion sperm. The aim of this paper was to review some of the current fluorescence-based methods used for the evaluation of equine semen as an alternative for the selection of breeding stallions, the diagnosis of subfertility/infertility, and the estimation of optimal protocols for sperm preservation under laboratory conditions.

RESUMEN

La evaluación del semen es un componente importante en la evaluación del potencial reproductivo de sementales, así como para el diagnóstico de casos de subfertilidad / infertilidad. Además, es necesario realizar una estimación precisa del daño sufrido por la célula espermática después de los procedimientos de refrigeración o criopreservación para el desarrollo de nuevos procedimientos a fin de mantener la integridad y la función del espermatozoide. Sin embargo, los métodos comúnmente utilizados para la evaluación de la calidad espermática (motilidad o morfología espermática) no están completamente asociados con el potencial de fertilización del espermatozoide en condiciones in vitro, y en el mejor de los casos están poco a moderadamente asociados con la fertilidad in vivo . En los últimos años, la introducción de métodos avanzados basados en el uso de fluorocromos para la evaluación espermática ha mejorado la capacidad del clínico y del investigador para explicar las diferencias en el potencial de fertilidad entre los sementales, así como evaluar críticamente el efecto de varios métodos para preservar el espermatozoide equino. El objetivo de este trabajo fue revisar algunos de los métodos actuales basados en fluorescencia que están siendo utilizados para la evaluación del semen equino como una alternativa para la selección de sementales reproductores, el diagnóstico de subfertilidad / infertilidad y la estimación de protocolos óptimos para la preservación del espermatozoide bajo condiciones de laboratorio.

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