Effects of Ovum Pick-up Frequency and FSH Stimulation: A Retrospective Study on Seven Years of Beef Cattle In Vitro Embryo Production     

R De Roover  JMN Feugang  PEJ Bols  G Genicot  Ch Hanzen 《Reproduction in domestic animals》2008,43(2):239-245

The aim of this retrospective study was to compare the number of follicles, cumulus oocyte complexes (COCs) and cultured In Vitro Produced (IVP) embryos obtained from 1396 non‐stimulated Ovum Pick‐up (OPU) sessions on 81 donor animals in a twice weekly OPU scheme. Results were obtained from 640 sessions following FSH‐LH superstimulation, on 112 donors subjected to OPU once every 2 weeks. The stimulation protocol started with the insertion of an ear implant containing 3 mg norgestomet (Crestar, Intervet, Belgium) 8 days before puncture (day ?8). The dominant follicle was ablated by ultrasound‐guided follicle puncture on day ?6. On day ?3 and day ?2, cows were injected with FSH (Ovagen, ICP) twice daily (8 am to 8 pm ), i.e. a total dose of 160 μg FSH and 40 μg LG per donor per stimulation cycle. Animals were punctured 48 h after the last FSH injection (day 0). Progesterone implants were removed the next day. Stimulated donor cows were treated with this protocol at 14‐day intervals. Follicles were visualized with a Dynamic Imaging ultrasound scanner, equipped with a 6.5 MHz sectorial probe. Follicles were punctured with 55 cm long, 18 gauge needles at an aspiration pressure corresponding to a flow rate of 15 ml/min. Cumulus oocyte complexes were recovered and processed in a routine IVF set‐up. Results demonstrate that, expressed per session, FSH stimulation prior to OPU increases production efficiency with significantly more follicles punctured and oocytes retrieved. However, when overall results during comparable 2‐week periods are considered (four non‐stimulated sessions vs one stimulated), more follicles are punctured and more oocytes are retrieved using the non‐stimulated protocol. No significant differences in the number of cultured embryos could be detected, indicating that FSH/LH stimulation prior to OPU might have a positive effect on in vitro oocyte developmental competence as more embryos are cultured with less, presumably better‐quality, oocytes.  相似文献   

Nanotechnology-based approach for safer enrichment of semen with best spermatozoa     

Casey L.Durfey  Sabrina E.Swistek  Shengfa F.Liao  Mark A.Crenshaw  Henry J.Clemente  Rooban V.K.G.Thirumalai  Christy S.Steadman  Peter L.Ryan  Scott T.Willard  Jean M.Feugang 《畜牧与生物技术杂志(英文版)》2019,(2)

Background: Advances in nanotechnology have permitted molecular-based targeting of cells through safe and biocompatible magnetic nanoparticles(MNP). Their use to detect and remove damaged spermatozoa from semen doses could be of great interest. Here, MNP were synthesized and tested for their ability to target apoptotic(annexin V) and acrosome-reacted(lectin) boar spermatozoa, for high-throughout retrieval in a magnetic field(nanoselection). The potential impacts of nanoselection on sperm functions and performance of offspring sired by sperm subjected to nanoselection were determined. Fresh harvested and extended boar semen was mixed with various amounts(0, 87.5, and 175 μg) of MNP-conjugates(Annexin V-MNP or Lectin-MNP) and incubated(10 to15 min) for 37 °C in Exp. 1. In Exp. 2, extended semen was mixed with optimal concentrations of MNP-conjugates and incubated(0, 30, 90, or 120 min). In Exp. 3, the synergistic effects of both MNP-conjugates(87.5 μg– 30 min)on spermatozoa was evaluated, followed by sperm fertility assessments through pregnancy of inseminated gilts and performance of neonatal offspring. Sperm motion, viability, and morphology characteristics were evaluated in all experiments.Results: Transmission electron microscopy, atomic force microscopy, and hyperspectral imaging techniques were used to confirm attachment of MNP-conjugates to damaged spermatozoa. The motility of nanoselected spermatozoa was improved(P 0.05). The viability of boar sperm, as assessed by the abundance of reactive oxygen species and the integrity of the acrosome, plasma membrane, and mitochondrial membrane was not different between nanoselected and control spermatozoa. The fertility of gilts inseminated with control or nanoselected spermatozoa, as well as growth and health of their offspring were not different between(P 0.05).Conclusions: The findings revealed the benefit of magnetic nanoselection for high-throughput targeting of damaged sperm, for removal and rapid and effortless enrichment of semen doses with highly motile, viable,and fertile spermatozoa. Therefore, magnetic nanoselection for removal of abnormal spermatozoa from semen is a promising tool for improving fertility of males, particularly during periods, such as heat stress during the summer months.  相似文献