Caracterización de las glicosidasas en el espermatozoide y su papel en la fecundación, con especial énfasis en la especie porcina

En las especies bovina y porcina se ha comunicado la presencia de glicosidasas ligadas a los espermatozoides (Hayashi et al., 2004). Otros autores han propuesto diferentes glicosidasas espermáticas que interactúan con carbohidratos específicos en la ZP en otras especies animales incluyendo al hombre (Tulsiani et al., 1989, 1990; Avilés et al., 1996; Song et al., 2000; Venditti et al., 2007, 2010).En el presente trabajo se llevó a cabo un estudio de las principales glicosidasas espermáticas para establecer su ubicación en el espermatozoide, el origen de su síntesis, la expresión génica y mediante FIV porcina valorar el papel de aquellas glicosidasas con mayor actividad enzimática (AE) en el reconocimiento de gametos, fecundación y desarrollo embrionario temprano. In bovine and porcine species, the presence of sperm bound glycosidases has been reported (Hayashi et al., 2004). Others studies have proposed different sperm glycosidases that interact with specific ZP carbohydrates in other species, including men (Tulsiani et al., 1989, 1990; Avilés et al., 1996; Song et al., 2000; Venditti et al., 2007, 2010). In the present work, the major sperm glycosidases were studied to establish their localization in the spermatozoon, the origin of their synthesis, their gene expression and through porcine IVF; we sought to define the role of the glycosidases with greater activity during gamete interaction, fertilization and early embryo development

Use of sex-sorted and unsorted frozen/thawed sperm and in vitro fertilization events in bovine oocytes derived from ultrasound-guided aspiration

The objective was to investigate the effects of sex-sorting on early fertilization events in ovum pick up (OPU) derived oocytes fertilized in vitro with frozen-thawed sperm at different co-incubation lengths. Eighty-four OPU sessions were carried out in 18 cyclic, dry and non-stimulated Holstein Friesian and German black pied cows. Ovum pick up oocytes were matured in vitro for 24 hours and fertilized with frozen-thawed sex sorted or unsorted sperm from the same ejaculate. Fertilization was achieved by two experimental protocols: 1) short gamete co-incubation length: 4, 8 and 12 hours; and 2) long gamete co-incubation length: 18 and 24 hours. After in vitro fertilization, ova were fixed and stained to identify early fertilization events. Sperm penetration, monospermy, pronuclear formation and syngamy did not differ, whether sexed or unsexed sperm was used. Overall, the findings demonstrate similar fertilizing potential between sex-sorted and unsorted sperm