Influence of addition of cobalamin to the extender on the post-thaw motility, viability, and DNA integrity of bovine ejaculate

Abstract

The present study was undertaken to investigate the effect of various concentrations of cobalamin (vitamin B12) in Bioexcell® extender on the spermatozoa quality of Simmental bulls. The semen was collected from 12 bulls by means of an artificial vagina. Vitamin B<sub>12</sub> at concentrations of 1.50, 2.50, 3.50, and 5.00 mg/mL was added to bovine Bioexcell® extender. The semen aliquots were cooled and preserved at 4°C. Their quality was evaluated during pre-freezing, and then the cooled semen samples were packaged into 0.25 ml straws. The straws were frozen in the vapor of liquid nitrogen, and stored at -196ºC in a container. The straws were thawed one day later, and the characteristics of spermatozoa were examined. The results showed that the effect of vitamin B<sub>12</sub> on the viability, DNA fragmentation and motility of spermatozoa was significant under both pre- and post-freezing conditions (p <0.05), and revealed that supplementation of the extender with B<sub>12</sub> improved the post-thaw spermatozoa quality in bulls.

Fertility Rate and Assessment of the Cytoprotective Capacity of Various Types of Holothuroidea Extracts on Spermatozoa

“…Sperm with high progressive motility are characterized by a greater ability to fertilize the oocyte than sperm with low progressive movement, which may be due to the fact of successfully penetrate the cumulus cells around the oocyte [13,14]. Bull sperm are susceptible to oxidative damage due to the structure of the membrane, which is rich in easily peroxidized polyunsaturated fatty acids, which negatively affects the integrity of the membrane [10,15]. The intact structures of the sperm membrane and acrosomes are necessary for the process of sperm capacitation, the acrosomal reaction and for the fertilization of the oocyte [16].…”

“…The intact structures of the sperm membrane and acrosomes are necessary for the process of sperm capacitation, the acrosomal reaction and for the fertilization of the oocyte [16]. During semen cryopreservation, changes in the acrosome membrane are observed, including membrane loss compared to non-frozen semen [15,17]. Cryoprotection of sperm acrosomes consists mainly in disintegration of acrosomes through damage to the acrosomal membrane.…”

“…This process is considered unfavorable because it results in a reduced quality of cryopreserved semen [10]. In order to increase protection against cryopreservation pf sperm cells, new techniques and methods pf cryopreservation are sought, consisting in adding antioxidants, proteins or extracts to the medium [15]. It has been shown that Holothuroidea extract has antioxidant properties, and the addition of these extract to semen before cryopreservation has a protective effect on sperm, preserving their viability and improving the fertilization capacity of cryopreserved semen [9,21].…”