A comprehensive meta-analysis on the efficacy of growth factor enriched cryo-agents in enhancing post-thaw quality of mammalian semen.

Objective: This study sought to evaluate the effect of growth factors (GFs) in semen extenders on the quality of post-thaw mammalian sperm using a meta-analysis approach. The main objective was to determine whether the addition of GFs could improve semen quality after cryopreservation.

Methods: A meta-analysis of various in vitro experiments using mammalian semen was conducted. Data were collected from multiple studies assessing the effects of GFs on sperm motility, viability, acrosome integrity, DNA integrity, and other key semen quality metrics. The analysis included a range of mammalian species, incorporating specific GFs into semen extenders during cryopreservation. The evaluation of sperm quality was conducted using parameters including motility, viability, acrosome integrity, plasma membrane integrity (PMI), DNA integrity, hyper-osmotic swelling test (HOST), malondialdehid (MDA), and computer-assisted semen analysis (CASA). Statistical analyses, including standardized mean differences (SMD), were performed to compare the effects of GF additives with control treatments.

Results: The addition of GFs into semen extenders significantly improved semen quality across various parameters, including motility, viability, acrosome integrity, and DNA integrity. The SMDs for motility, viability, acrosome integrity, PMI, DNA integrity, HOST, MDA, and CASA parameters were significantly higher in the GF-treated groups than those of the controls, with observed values of 2.56±0.303, 3.53±0.423, 1.22±0.351, 1.82±0.362, 8.73±2.514, 2.02±0.426, and 6.30±2.87, respectively. Notably, the addition of GFs maintained semen quality in most mammalian species (p<0.05, SMD>0.5), with the exception of boar semen.

Conclusion: The present study demonstrated that the addition of GFs into semen extenders significantly enhances semen quality during cryopreservation across various mammalian species. This improvement is likely due to the antioxidants and repair factors found in the GFs. Each GF appeared to exert a distinct effect on sperm, subsequently enhancing sperm viability after thawing. The findings have important implications for improving reproductive technologies in mammalian species, particularly regarding cryopreservation and artificial insemination procedures.