الفهرس 
Rabbits as a modelOnly 14 pages are availabe for public view
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Abstract
In rabbit farms, artificial insemination is usually undertaken using preserved
semen. However, increased reactive oxygen species levels during preservation
produce sperm dysfunction. Mammalian spermatozoa are highly susceptible to
reactive oxygen species (ROS) stress. This study assessed the influence of
supplementing the rabbit semen extender with various concentrations of
glutathione (GSH) and taurine at 24, 48, and 72 h postchilling at 5°C. Semen
samples were collected from 20 New Zealand bucks, and ejaculates with
standard color, motility (>85%), about 0.5 mL volume, and ∼400 ×106
/mL
concentration were used and diluted with extenders supplemented with 0.5, 1,
and 2 mM of GSH and 1, 5, and 10 mM of taurine and chilled at 5°C.
Nonsupplemented samples were used as a control. Sperm’s progressive motility,
acrosome reaction, and extracellular oxidative stress biomarkers such as MDA
contents and SOD, CAT, and GPx concentrations, total cholesterol, triglyceride,
total protein, GPT, fructose and intracellular transcriptomic levels of SOD and
CAT genes were assessed. Results showed that, in general, glutathione and
taurine supplementation significantly improved sperm motility and viability percent
compared to control after 24, 84 and 72h post chilled storage. The
supplementations improved the sperms kinetics by reducing cooling-associated
stress, which was ascertained by lowering MDA concentration, preserving
membrane stability through obvious decreasing of GPT, chol, triglyceride, total
protein at seminal level which implies sperm membrane stability and increasing
SOD, CAT, and GPx activities . Increasing the levels of antioxidant enzymes in
the extender was due to the increasing mRNA copies of the SOD and CAT genes.
Furthermore,maintaining the fructose levels in the extender. In conclusion, GSH
and taurine supplementation to the extender had protective influences on the in
vitro rabbit semen quality during chilled storage for up to72 h at 5°C.