Seasonal changes in ROS concentrations and sperm quality in unfrozen and frozen-thawed stallion semen.
Abstract: Oxidative stress is regarded as an important cause of sperm damage during cryopreservation. However, seasonal changes in oxidative status in unfrozen and frozen-thawed stallion sperm have not been well established. We tested the hypothesis that sperm ROS concentrations and lipid peroxidation change between breeding and non-breeding seasons and influence quality of unfrozen and frozen-thawed sperm. Eighteen ejaculates from six Warmblood stallions (8-21 y) known to be fertile, were collected in winter and summer and processed for freezing. After 90 min at +4 °C, some straws from each ejaculate were not frozen (unfrozen), whereas the remainder were frozen by N2 vapors, plunged in N2 and thawed (frozen-thawed). Rapid cells (RAP; determined by CASA), plasma membraneacrosome integrity (PMAI), high mitochondrial membrane potential (Mpos), low intracellular Ca2+ concentration (Fneg), membrane lipid peroxidation (BODIPY), intracellular ROS concentrations (DCFH, MitoSOX) and chromatin fragmentation (DFI%) were evaluated by flow cytometry in both groups and at intervals during incubation at +37 °C for 24 h. Overall, ROS concentrations and lipid peroxidation were higher and faster (P < 0.0001) in winter versus summer, DFI% was lower in winter versus summer (P < 0.0001), but similar between the two groups within season. There were moderate positive correlations in both seasons between DFI% and MitoSOX, DCFH, BODIPY in both groups, whereas a negative correlation, stronger in winter, was evident between sperm quality (RAP, PMAI, Mpos, Fneg) and BODIPY, DCFH, MitoSOX. There were no differences between seasons for RAP, PMAI, Mpos and Fneg. In conclusion, ROS-related parameters were higher in winter than in summer, without a negative effect on sperm quality. We concluded that increased ROS concentrations were less deleterious to sperm than freezing-thawing. Furthermore, incubation at +37 °C and sequential analysis were useful to assess sperm resistance.
Copyright © 2019 Elsevier Inc. All rights reserved.
Publication Date: 2019-12-24 PubMed ID: 31927419DOI: 10.1016/j.theriogenology.2019.12.016Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
This study explores the impact of seasonal changes on oxidative stress and quality of stallion sperm, both in its natural state and after being frozen and thawed. The results suggest that seasonal variations do result in shifts in reactive oxygen species (ROS) concentrations and lipid oxidation, but without a detrimental effect on sperm quality.
Objective of the Study
- The research seeks to investigate the hypothesis that changes in sperm reactive oxygen species (ROS) concentrations and lipid peroxidation occur between the breeding and non-breeding seasons for Warmblood stallions and that these changes affect the quality of unfrozen and frozen-thawed sperm.
Methodology
- Eighteen ejaculates from six Warmblood stallions, proven to be fertile, were collected during both winter and summer. These were prepared for freezing. Some of the samples were left in an unfrozen state at a temperature of +4°C for 90 minutes. The rest of the specimens were frozen by N2 vapors, plunged in N2, and then thawed (referred to as the frozen-thawed group).
- The researchers then evaluated several indicators of sperm quality. These include assessments of rapid cells or RAP (determined by CASA), plasma membrane-acrosome integrity (PMAI), high mitochondrial membrane potential (Mpos), low intracellular Ca2+ concentration (Fneg), membrane lipid peroxidation (BODIPY), intracellular ROS concentrations (MitoSOX and DCFH), and chromatin fragmentation (DFI%) using the method of flow cytometry.
- These assessments were made at intervals during an incubation period of 24 hours at +37°C.
Key Findings
- Overall, the study found that ROS concentrations and the rate of lipid peroxidation were higher in winter as compared to summer, and chromatin fragmentation was lower in winter against summer. However, these changes were similar for both the unfrozen and frozen-thawed groups within each season.
- The study observed moderate positive correlations between DFI% and MitoSOX, DCFH, BODIPY in both groups and both seasons, but there was a stronger negative correlation in winter between sperm quality indicators (RAP, PMAI, Mpos, Fneg) and BODIPY, DCFH, MitoSOX.
- No significant changes between the two seasons were found for RAP, PMAI, Mpos, and Fneg.
Conclusion
- The study concludes that while ROS-related parameters were found to be higher in winter than in summer, they did not have a negative effect on sperm quality. The findings suggest that higher ROS concentrations are less damaging to sperm than freezing-thawing.
- The study also signaled the value of using incubation at +37°C and sequential analysis for assessing sperm resistance.
Cite This Article
APA
Mislei B, Bucci D, Malama E, Bollwein H, Mari G.
(2019).
Seasonal changes in ROS concentrations and sperm quality in unfrozen and frozen-thawed stallion semen.
Theriogenology, 144, 89-97.
https://doi.org/10.1016/j.theriogenology.2019.12.016 Publication
Researcher Affiliations
- AUB-INFA National Institute of Artificial Insemination, University of Bologna, Italy. Electronic address: beatrice.mislei@unibo.it.
- Department of Veterinary Medical Sciences, University of Bologna, Italy.
- Clinic of Reproductive Medicine, Vetsuisse-Faculty University of Zurich, Switzerland.
- Clinic of Reproductive Medicine, Vetsuisse-Faculty University of Zurich, Switzerland.
- AUB-INFA National Institute of Artificial Insemination, University of Bologna, Italy; Department of Veterinary Medical Sciences, University of Bologna, Italy.
MeSH Terms
- Animals
- Cryopreservation / veterinary
- Freezing
- Horses / physiology
- Male
- Photoperiod
- Reactive Oxygen Species
- Seasons
- Semen Analysis / veterinary
- Sperm Motility
Conflict of Interest Statement
Declaration of competing interest None.
Citations
This article has been cited 5 times.- Pintus E, Ros-Santaella JL. Impact of Oxidative Stress on Male Reproduction in Domestic and Wild Animals.. Antioxidants (Basel) 2021 Jul 20;10(7).
- Bazzano M, Laus F, Spaterna A, Marchegiani A. Use of nutraceuticals in the stallion: Effects on semen quality and preservation.. Reprod Domest Anim 2021 Jul;56(7):951-957.
- Zhang B, Wang Y, Wu C, Qiu S, Chen X, Cai B, Xie H. Freeze-thawing impairs the motility, plasma membrane integrity and mitochondria function of boar spermatozoa through generating excessive ROS.. BMC Vet Res 2021 Mar 22;17(1):127.
- Gaitskell-Phillips G, Martín-Cano FE, Ortiz-Rodríguez JM, Silva-Rodríguez A, Gil MC, Ortega-Ferrusola C, Peña FJ. In Stallion Spermatozoa, Superoxide Dismutase (Cu-Zn) (SOD1) and the Aldo-Keto-Reductase Family 1 Member b (AKR1B1) Are the Proteins Most Significantly Reduced by Cryopreservation.. J Proteome Res 2021 May 7;20(5):2435-2446.
- El Kadili S, Kirschvink N, Raes M, Bister JL, Archa B, Douaik A, Chentouf M. Influence of Season and Liquid Storage at 16 °C on Beni Arouss Bucks' Semen Quality.. Animals (Basel) 2020 Oct 29;10(11).
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
