The role of environmental optimization for storing bulls' sperm cells

Graphene oxide and silymarin combination: A novel approach to improving post-cryopreservation quality of ram sperm

Graphene oxide (GO) has been extensively studied for its diverse biomedical applications, including drug delivery, imaging, and tissue engineering. Silymarin, as a flavonoid complex derived from the milk thistle plant, has recently shown potential health benefits, particularly concerning reproductive health. This study aims to evaluate the effects of GO and silymarin supplementation, both individually and in combination, on the characteristics of frozen-thawed ram sperm. Semen samples were collected using standard artificial insemination (AI) techniques with an artificial vagina. The collected semen was evaluated and cryopreserved in a tris-based extender containing varying concentrations of silymarin and GO (0, 10, or 20 μg/mL) or their combination. Post-thaw assessments evaluated sperm motility, viability, morphological abnormalities, DNA integrity, membrane integrity, malondialdehyde (MDA) levels, superoxide dismutase (SOD) activity, and total antioxidant capacity (TAC). Our findings revealed that the combination of 20 μg/mL silymarin and 20 μg/mL GO significantly enhanced total motility, viability, membrane integrity, and DNA integrity of sperm. Additionally, this treatment effectively reduced morphological abnormalities and MDA levels post-thawing. Notably, SOD and TAC activities were improved following the freeze-thaw compared to other treatment groups. In conclusion, the combination of silymarin and GO significantly improves the quality of frozen-thawed ram sperm by enhancing sperm parameters while reducing oxidative stress markers. The results suggest their potential as effective additives in cryopreservation protocols, providing a promising avenue for improving reproductive outcomes in rams and potentially other livestock species.

Bull Semen Obtained on Beef Farms by Electroejaculation: Sperm Quality in the First Two Hours of Storing with Different Extenders and Holding Temperatures

Sperm quality decreases over time, so bull semen may need to be preserved after field collection. However, the effect of handling such semen samples from commercial farms and placing them in very short-term storage has not been elucidated. Therefore, ejaculate from 25 bulls from 1 dairy and 14 beef cattle farms were collected under farm conditions and evaluated for semen quality during the first two hours after collection. Two commercial extenders (AndroMed^® and BIOXcell^®) and two different storage temperatures (5 °C and room temperature) were used to evaluate the influence on semen quality and sperm kinetics in ejaculates grouped into three evaluation times, based on time since collection (Time 1: <75 min, n = 7; Time 2: 75-105 min, n = 11; and Time 3: 105-120 min, n = 7). Classical semen parameters, sperm motion kinetics by CASA and colony-forming units were assessed. The differences between both extenders in curvilinear and straight-line velocities (VCL and VSL) for the different time groups (Time 2 and Time 3) were statistically significant for p < 0.05. AndroMed^® showed lower VSL, straightness and linearity in sperm compared to BIOXcell^® (p < 0.05). In conclusion, AndroMed^® induced more curvilinear movement, while BIOXcell^® stimulated straighter motility.