In vitro Maturation of Oocytes from Santa Ines Ewes Subjected to Consecutive Sessions of Follicular Aspiration by Laparoscopy

Abstract

The success of embryo production in vitro depends upon the use of an efficient oocyte retrieval technique, and the best results have been obtained by laparoscopic aspiration. The aim of this study was to evaluate the effect of consecutive sessions of follicular aspiration on the quantity, quality and in vitro maturation competence of oocytes obtained from ewes subjected to hormonal stimulation. Six Santa Ines ewes underwent nine sessions of follicular aspiration by laparoscopy with a 7-day interval between sessions, totalling 56 aspirations. After 24 h of culture, oocytes were stained and classified according to the stage of nuclear and cytoplasmic maturation. Oocyte retrieval rate was 61.4 ± 2%, resulting in a total of 249 oocytes. No significant variation was observed between sessions (p > 0.05). The average number of oocytes retrieved from each ewe was 6.4 ± 2 per session and 42 ± 4 in total. No significant difference was observed between the frequencies of the different stages of nuclear maturation: 32.72% mature, 40.74% immature and 26.54% degenerated/indeterminate oocytes; however, a significant difference was observed between the frequencies of the different stages of cytoplasmic maturation: 10.7% mature, 73.25% immature and 16.05% degenerated/indeterminate oocytes. No significant difference was observed in nuclear or cytoplasmic maturation between the weeks of procedure. We conclude that after nine consecutive sessions of follicular aspiration, the quantity and quality of retrieved oocytes remained unchanged as well as the levels of nuclear and cytoplasmic maturation obtained, demonstrating the viability of this technique for repetitive follicular aspirations on the same donor.

Ovum pick‐up and in vitro maturation in spotted paca (Cuniculus paca—Linnaeus, 1766)

“…D‐cloprostenol dose used in those females was also adopted based on work with small ruminants and small rodentia. However, in all those studies, the doses shown to be efficient, since it was not reported significant presence of corpus luteum in all of them, corroborating our responses (Padilha et al, ). In small rodentia, cloprostenol administered in higher dosis is efficient mainly if combined with progesterone, reaching up to 100% the response in oestrous synchronization and ovulation (Pallares & Gonzalez‐Bulnes, ).…”

“…Recovery and maturation rates did not differ during the periods of the experiment. Similar results were found in sheep (Padilha et al, ; Teixeira et al, ), but it was observed a decrease in oocyte quality in goats (Cordeiro et al, ) and cows (Broadbent, Dolman, Watt, Smith, & Franklin, ) with repeated follicular aspirations. These results may suggest that spotted paca do not develop antibodies to FSH and eCG from the repeated use of these hormones.…”

“…In vitro production (IVP) optimizes the number of offspring per female and enables the use of young animals, pregnant or lactating females, those with acquired infertility and endangered species (Teixeira et al, ). However, for IVP to be successful, knowledge of gamete morphology and how they behave during in vitro maturation (IVM) is essential, as full oocyte maturation is required for embryo development and is thus a limiting factor in embryo production (Padilha et al, ).…”

Distribution of cortical granules and meiotic maturation of canine oocytes in bi-phasic systems

“…Thus, the dynamic of cortical granules (CG) changes during oocyte development, and the CG staining pattern has been used in different species as an indicator of cytoplasmic maturation (Carneiro et al 2002;Takano et al 2002;Liu et al 2005;Padilha et al 2014). In the dog, there is only one report that investigates the relationship between cortical granule distribution and chromatin configuration during in vitro maturation through CG staining using Hoescht-fluorescein isothiocyanate-conjugated Lens culinaris agglutinin (FITC-LCA; Apparicio et al 2011).…”

Laparoscopic ovum pick-up in spotted paca ( Cuniculus pacas )

“…Laparoscopic ovum pick-up (LapOPU) used for in vitro production (IVP) is one of the leading reproductive biotechniques in assisted reproduction, highlighted for being less invasive, provide a quicker recovery and the possibility of being held several times in the same female as already described in some domestic species (Teixeira et al, 2011;Cordeiro et al, 2014;Padilha et al, 2014;Teixeira et al, 2015).…”