Egg Yolk Protective Effect in Boar Spermatozoa Cooled at 5ºC
Keywords:
Androhep Plus, boar sperm, CASA, cold shock, egg yolk, flow cytometryAbstract
Nowadays, many boar reproduction researches are directed to improve extenders and to increase cold shock protection of semen. Little research is focused on the influence of egg yolk combined with alternative cold shock protective media. Egg yolk could interfere with other compounds present in the extender composition. The influence of egg yolk addition was assessed in boar sperm cells, cooled at 5ºC, to elucidate its effect on motility and membrane integrity. Flow Cytometry and Computer Assisted Semen Analysis (CASA) were used to determine the rate of sperm with intact plasma and acrosomal membrane, respectively the sperm cells motility. Statistical analyses (T-Test) were performed using GraphPad Prism version 5.00. Androhep Plus supplemented with 20% egg yolk (AhPlus+20%EY) indicated a higher cold shock protection in progressive motility (93.9±2.64%) and membrane integrity (79.78±4.14%), rather than the extender without egg yolk (p<0.01, respectively p<0.05). The results of the this study showed that egg yolk addition to AhPlus do not interfere with its compounds, the data being in a close range with those obtained by using the standard Lactose Egg Yolk extender (p>0.05). The combination egg yolk-AhPlus seems to be an alternative to standard extenders, conferring stability in boar sperm cells against cold shock.
References
Bengt Eriksson, Cryopreservation of boar semen, PhD Thesis, Swedish University of Agricultural Sciences, 2000
Young, B, Dewey, C., and Friendship, B., The effect of on-farm semen storage temperature on stored semen quality. In proceedings of American Association of Swine Veterinarians, 2005. pp 357-360
Johnson, L. A., Weitze, K. F., Fiser, P. and Maxwell, W. M. C., Storage of boar semen. Anim.Reprod. Sci., 2000, 62, 143-172
Watson, P. F. and Plummer, J. M., The response of boar sperm membranes to cold shock and cooling. In:Johnson L.A., Larsson K. (Eds.), Deep freezing of boar semen, SLU, Uppsala, Sweden, 1985, pp. 113-127
Pursel, V. G., Johnson, L. A., Schulman, L. L., Interaction of extender composition and incubation period on cold shock susceptibility of boar spermatozoa, J.Anim. Sci., 1972, 35, 580-584
Pursel, V. G., Johnson, L. A. and Schulman, L. L., Effect of dilution, seminal plasma and incubation period on cold shock susceptibility of boar spermatozoa, J. Anim. Sci., 1973, 37, 528-531
Drobnis, E. Z., Crowe, L. M., Berger, T., Anchordoguy, T. J., Overstreet, J. W., Crowe, J. H., Cold shockdamage is due to lipid phase-transitions in cell-membranes — a demonstration using sperm as a model. J.Exp. Zool., 1993, 265, 432–437
Holt, W. V., Head, M. F., North, R. D., Freeze-induced membrane damage in ram spermatozoa is manifested after thawing — observations with experimental cryomicroscopy, Biol. Reprod., 1992, 46, 1086–1094
Holt, W. V., Basic aspects of frozen storage of semen, Animal Reproduction Science, 2000, 62, 3-22
Holt, W. V., Morris, G. J., Coulson, G., North, R. D., Direct observation of cold-shock effects in ram spermatozoa with the use of a programmable cryomicroscope, J. Exp. Zool., 1988, 246, 305–314
Saikhun, J., Thongtipsiridech, S., Kornkaewrat, K., Mahasawangkul, S., Angkawanish, T., Jansitthiwate, S., Boonprasert, K., Pinyopummin, A., Practical Elephant Semen Analysis Techniques, Managing the Health and Reproduction of Elephant Populations in Asia, 2007, 83-87
De Leeuw, F. E., Chen, H. C., Colenbrander, B., Verkleij, A., Cold-induced ultrastructural changes in bull and boar sperm plasma membranes, Cryobiology, 1990, 27, 171–183
Holt, W. V., North, R. D., Partially irreversible cold-induced lipid phase transitions in mammalian sperm plasma membrane domains: freeze-fracture study, J. Exp. Zool., 1984. 230, 473–483
