Influence of age on superoxide anion production and oxidative damage in cryopreserved semen of Nelore bulls

• Grant number: 11/22741-7
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2012
• End date: February 28, 2014
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Marion Burkhardt de Koivisto
• Grantee: Marion Burkhardt de Koivisto
• Host Institution: Faculdade de Medicina Veterinária (FMVA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

It is known that high levels of reactive oxygen species (ROS) in semen reduce the fertilizing potential of sperm cells. This study will investigate whether the oxidative damage, caused in bovine spermatozoa, varies with age and if the methods are effective in assessing oxidative stress for this specie. For that 40 animals kept in an artificial insemination center will be distributed equally into four groups: group 1 from 20 to 24 months (2 years), group 2 from 59 to 72 months (4-5 years), group 3 from 84 to 112 months (7-9 years) and group 4 from134 to 172 months (11-14 years). The animals will be collected twice weekly by artificial vagina completing three ejaculates per bull (n=120). The ejaculates will be frozen in accordance with the established standards of the artificial insemination center. The frozen semen will be evaluated for physical parameters (motility, vigor, concentration and morphology), production of ROS (superoxide anion) evaluated by DHE fluorochrome and Sytox ® Green, lipid peroxidation through the probe BODIPY 581/591 C11 and production DNA damage promoted ROS using the 8 - oxoguanina test. (AU)