Advances in Cryopreservation of Bull Sperm

Abstract

Cryopreservation of semen and artificial insemination have an important, positive impact on cattle production, and product quality. Through the use of cryopreserved semen and artificial insemination, sperm from the best breeding bulls can be used to inseminate thousands of cows around the world. Although cryopreservation of bull sperm has advanced beyond that of other species, there are still major gaps in the knowledge and technology bases. Post-thaw viability of sperm is still low and differs significantly among the breeding bulls. These weaknesses are important because they are preventing advances both in fundamental science of mammalian gametes and reproductive biotechnology. Various extenders have been developed and supplemented with chemicals to reduce cryodamage or oxidative stress with varying levels of success. More detailed insights on sperm morphology and function have been uncovered through application of advanced tools in modern molecular and cell biology. This article provides a concise review of progress in the cryopreservation of bull sperm, advances in extender development, and frontiers using diverse techniques of the study of sperm viability. This scientific resource is important in animal biotechnology because with the advances in discovery of sperm fertility markers, there is an urgent need to improve post-thaw viability and fertility of sperm through enhanced cryopreservation for precision agriculture to produce food animals to ensure food security on the global scale.

Effect of vitamin E addition to frozen Simmental bull semen extender on post-thawing quality

“…Vitamin E as an antioxidant has an essential role in giving protection to the membrane. Vitamin E could give a positive effect on the improvement of sperm motility, membrane integrity and membrane potential [2]. Vitamin E presence in semen extender has important role as a sperm antioxidant compound to prevent peroxidation reaction on the sperm membrane.…”

“…ROS formation on spermatozoa caused by chain reaction on membrane peroxidation with other oxides such as hydrogen peroxide and disruption of metabolism in spermatozoa cell. ROS was capable of inhibiting cell metabolism and the utilization of ATP from cell mitochondria [2,13]. progressive motility of sperm movement.…”

“…Sperm abnormality is a form of physical defect mostly on the spermatozoa cell body. A primary abnormality is a form of defection on the sperm cell head and acrosome cap, while secondary abnormality is a form of defection mostly on the tail part of the sperm cell [2,19]. This research focused mainly on secondary abnormality which was mostly occurred during frozen semen production.…”

“…Frozen semen production consisted of a series of the process including semen dilution in extender, freezing, cold storage and post-thawing evaluation. During cooling and freezing process, sperm cells are susceptible to get the harmful effect from unbalanced osmotic pressure, protein denaturation, cellular acidosis, energy loss, membrane breakdown, crystallization of cells body, destabilization of the cytoskeleton and formation of free radicals or reactive oxygen species (ROS) [2].…”

“…Lipid peroxidation on spermatozoa will result in the loss of motility, decrease in cell fructolysis and respiration activity and leakage of cell fluid through damaged membrane. Antioxidants such as vitamin E are known for their ability to give protection to the sperm membrane by inhibiting the formation of ROS and lipid peroxidation [2].…”