Oocyte Quality, In Vitro Fertilization and Embryo Development of Alpaca Oocytes Collected by Ultrasound-Guided Follicular Aspiration or from Slaughterhouse Ovaries

SIMPLE SUMMARY: We compared the morphological quality and the in vitro developmental competence of cumulus–oocyte complexes (COCs) from live vs. slaughtered alpacas. COCs were recovered using: (i) manual aspiration in slaughterhouse ovaries (n = 15 females), or (ii) ovum pick-up (OPU) in live superstimulated alpacas (n = 13). COCs recovered were morphologically evaluated. Grade I–III COCs were in vitro matured and fertilized afterwards using fresh alpaca spermatozoa. Zygotes were in vitro cultured for seven days. The proportion of COCs recovered was similar between groups, but the mean number of COCs collected from individual ovaries was greater (p < 0.05) in slaughterhouse ovaries. A higher (p < 0.05) percentage of grades III and IV and a lower (p < 0.05) percentage of grade I COCs was obtained using OPU. Although, no significant difference in the percentage of cleavage and morula formation was observed between groups, the number of blastocysts, regarding cleavage and COCs collected, was higher (p < 0.007 and p < 0.0002, respectively) in the OPU group. However, the total number of blastocysts per female did not differ between groups. The recovery rate and morphological quality of COCs was significantly higher when follicles were manually aspirated from slaughterhouse alpaca ovaries; however, a greater developmental potential was observed in oocytes obtained from live alpaca. ABSTRACT: The morphological quality and the in vitro developmental competence of cumulus-oocyte complexes (COCs) collected from in vivo or slaughtered alpacas was compared. COCs were recovered from ovarian follicles using: (i) manual aspiration in ovaries of alpacas (n = 15) sacrificed at a local slaughterhouse, or (ii) transrectal ultrasound-guided follicular aspiration (or ovum-pick-up, OPU) in live alpacas (n = 13) 4 days after the administration of an ovarian superstimulation protocol (200 UI eCG). COCs recovered from both groups were morphologically evaluated and graded. Grade I to III COCs were in vitro matured for 26 h and in vitro fertilized afterwards for 20 h using fresh alpaca epididymal spermatozoa. Presumptive zygotes from both groups were in vitro cultured for 7 days. The proportion of COCs recovered over the total number of follicles punctured was similar between groups, but the mean number of COCs collected from individual ovaries was greater (p < 0.05) in slaughterhouse ovaries. A significantly higher (p < 0.05) percentage of low-quality COCs (grades III and IV) and a lower (p < 0.05) percentage of grade I COCs was obtained using OPU. The number of blastocysts, regarding cleavage and COCs collected, was higher (p < 0.007 and p < 0.0002 respectively) for COCs collected by OPU; however, the total number of blastocysts per female did not differ between groups. We can conclude that the recovery rate and morphological quality of COCs was significantly higher when follicles were manually aspirated from slaughterhouse alpaca ovaries; however, a statistically higher developmental potential was observed in oocytes collected by OPU from live alpaca donors.