Journal
THERIOGENOLOGY
Volume 86, Issue 4, Pages 957-962Publisher
ELSEVIER SCIENCE INC
DOI: 10.1016/j.theriogenology.2016.03.019
Keywords
Stallion; Spermatozoon; Cryopreservation; alpha-Tocopherol; Freezing rate; Heterologous in vitro fertilization
Categories
Funding
- Fundo Regional para a Ciencia-Direccao Regional Educacao, Ciencia e Cultura-Azores [BD M312/F/002/2010]
Ask authors/readers for more resources
The effects of supplementation of alpha-tocopherol and different freezing rates (FRs) on the ability of stallion sperm to fertilize bovine oocytes with intact zona pellucida were investigated, in an attempt to develop a model to assess cryopreserved sperm function. Semen was obtained from four purebred Lusitano stallions (n = 4). Each ejaculate was subjected to cryopreservation with a commercial extender (Ghent, Minitub Iberia, Spain), without any supplementation (control) or supplemented with 2-mM alpha-tocopherol. The semen was exposed to two different FRs between 5 degrees C and -15 degrees C: slow (5 degrees C/min) and moderate (10 degrees C/min). After thawing, the viability (SYBR (R)-14 and propidium iodide [PI]), mitochondrial membrane potential (JC-1, 5,5',6,6'-tetrachloro-1,1',3,3'tetraethylbenzimidazolyl carbocyanine iodine) and membrane lipid peroxidation (C-11-BODIPY581/591) of each sample were determined by flow cytometry. Moreover, the heterologous IVF rate was measured to evaluate the fertilization capacity of postthaw semen in the four different treatments. For both extenders, the viability was higher for spermatozoa cooled slowly (39.40 +/- 2.17 vs.17.59 +/- 2.25-control; 31.96 +/- 2.19 vs. 11.46 +/- 134 Tocopherol; P < 0.05). The a-tocopherol extender improved (P < 0.05) postthaw lipid peroxidation (10.28 +/- 0.70 vs. 15.40 +/- 0.95-slow FR; 10.14 +/- 0.40 vs. 13.48 +/- 0.34-moderate FR); however, it did not improve viability and mitochondrial membrane potential. Regarding the IVF rate, in the moderate FR, alpha-tocopherol supplementation reported a higher percentage of IVF (20.50 +/- 2.11; P < 0.05), comparing with the control (14.00 +/- 1.84). Regarding the slow FR, no significance differences were observed for percentage of IVF between the two extenders and the FRs. However, it seems that the alpha-tocopherol supplementation improved the IVF rate. In conclusion, this research reported that bovine oocytes intact zona pellucida can be used to evaluate the quality of postthaw stallion semen and alpha-tocopherol supplementation in the stallion freezing extender might exert a protective effect against oxidative damage during heterologous IVF. (C) 2016 Elsevier Inc. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available