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The Effects of Extender Energetic Substrate Type on Goat Sperm Stored at 17 °C
by
, ,
Sabrina Gacem
1
,
Eva Mocé
2,*,
Carmen Gozalbo
1,
Marta Albuixech-Benetó
1,
Inés C. Esteve
2,
Amparo Martínez-Talaván
2 and
Miguel A. Silvestre
1,* 1
Departamento de Biología Celular, Biología Funcional y Antropología Física, Universitat de València, 46100 Valencia, Spain
2
Centro de Investigación y Tecnología Animal, Instituto Valenciano de Investigaciones Agrarias, 12400 Castellón, Spain
*
Authors to whom correspondence should be addressed.
Biology 2025, 14(7), 782; https://doi.org/10.3390/biology14070782 (registering DOI)
Submission received: 26 May 2025
/
Revised: 18 June 2025
/
Accepted: 19 June 2025
/
Published: 27 June 2025
(This article belongs to the Section Developmental and Reproductive Biology)
Simple Summary
Understanding how energy sources influence sperm performance could lead to optimized semen preservation techniques and ultimately benefit reproductive technologies and livestock breeding programs. Currently, extenders formulated for goat buck sperm primarily contain glucose as the main energy source. However, despite recent efforts to optimize extenders, no significant successful improvement in artificial insemination with cooled semen stored for over 24 h has been reported. The current study aimed to investigate the effect of pyruvate, lactate, glucose, and fructose on sperm during refrigeration at 17 °C. Pyruvate proved to maintain better sperm quality parameters than the other substrates after 48 h of storage at 17 °C in PBS.
Abstract
Artificial insemination in goats commonly relies on refrigerated semen doses, yet the optimal energetic substrate to support sperm metabolism remains unclear. This study aimed to evaluate the effects of different energetic substrates on goat buck sperm metabolism and motility when refrigerated at 17 °C. Semen from six Murciano-Granadina male goats were collected and diluted in PBS supplemented with 35 mM of either glucose, fructose, pyruvate, or lactate in the first experiment. In the second experiment, the effects of varying concentrations of pyruvate and/or glucose, NaCl supplementation, and the osmolarity on sperm quality parameters were assessed. Semen was stored at 17 °C for 48 h and evaluated for motility using the CASA system, as well as for viability, mitochondrial membrane potential, and mitochondrial ROS by flow cytometry. The results show that pyruvate and lactate extenders outperformed the others, preserving higher total motility, progressivity, and viability of spermatozoa over 48 h, even at a concentration lower than 35 mM, as in the case of pyruvate. In contrast, glucose had a detrimental effect on sperm quality, reducing viability and healthy population rates while increasing motility, especially at higher concentrations. NaCl supplementation and osmolarity had no significant effect on any of the sperm quality parameters. In conclusion, pyruvate maintains a higher quality and motility of sperm stored at 17 °C in PBS in comparison with a glucose-supplemented extender.
