SAEVA Congress 2018 Proceedings | 12-15 February 2018 | ATKV Goudini Spa
found in their CoQ10 can vary considerably. As CoQ10 is absorbed from the g-i tract
as ubiquinol, it makes great sense to administer the supplement in that form as its
bioavailability is greatly enhanced.
Stallion Fertility Oxidative stress has a clearly recognized role in male infertility, and
several studies have been focused on the role of antioxidant therapy on semen
quality and reproductive outcome in a variety of species, but not the horse.
Spermatozoa physiologically produce ROS that are involved in protein tyrosine
phosphorylation during sperm capacitation; ie, this process is essential to normal
sperm function. ROS come not only from spermatozoal mitochondria, but also from
neutrophils and macrophages.
High ROS levels can exceed the sperm antioxidant defenses and have a strong
negative effect on semen quality. This oxidative stress is now recognized as a major
contributing factor to male infertility. Oxidative sperm damage includes DNA
fragmentation, altered mobility and reduced capacity of the spermatic membrane to
fuse with oocytes. The susceptibility of spermatozoa to oxidative stress damage is
due to (i) large amounts of polyunsaturated fatty acids in the phospholipid membrane;
(ii) limited anti-oxidizing capacities of the cell; and (iii) the great ability of spermatozoa
to generate ROS, although indispensable, at physiological levels, for adequate sperm
functionality.
Antioxidants have been successfully used to treat male infertility and to improve
sperm motility and membrane integrity stability in men, bulls, rams, goats, boars and
dogs. Although the importance of CoQ10 in health and disease and its critical role in
cellular bioenergetics have been well established in various species, there is a total
lack of information on the effects of dietary supplementation of CoQ10 on
stallion semen quality. However, given the safety of the substance and the positive
effects of supplementation on male fertility in other species, there is good reason to
believe that there will be similar beneficial effect on the fertility of stallions, especially
those with heavy work loads.
Another significant source of sperm oxidative stress arises from sperm handling and
cryopreservation procedures during assisted reproduction. The supplementation of
bovine sperm media with CoQ10, zinc and D-aspartate improved the developmental
competence of embryos produced in vitro and their ability to implant and give rise to
healthy calves.
The most commonly used technique in the global equine industry for assisted
reproduction is artificial insemination with fresh, cooled, or frozen semen. High-quality
semen is dependent on several major factors, including proper management, good
health care, and sufficient nutrients to meet the needs of reproductive male horses.
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