Applying embryo cryopreservation technologies to the production of domestic and black-footed cats.

Our objectives were (i) compare in vitro development of early cleavage stage domestic cat embryos after cryopreservation by minimal volume vitrification vs a standard slow, controlled-rate method, (ii) determine viability of vitrified domestic cat embryos by oviductal transfer into synchronous recipients and (iii) evaluate in vivo survival of black-footed cat (BFC, Felis nigripes) embryos after intra- and inter-species transfer. In vitro-derived (IVM/IVF) cat embryos were used to evaluate in vitro development after controlled-rate cryopreservation vs vitrification vs controls. Blastocyst development was similar in both groups of cryopreserved embryos (22-26%), but it was lower (p < 0.

In vivo survival of domestic cat oocytes after vitrification, intracytoplasmic sperm injection and embryo transfer.

We evaluated: (1) cleavage rate after IVF or intracytoplasmic sperm injection (ICSI) of in vivo- and in vitro-matured oocytes after vitrification (experiment 1); and (2) fetal development after transfer of resultant ICSI-derived embryos into recipients (experiment 2). In vivo-matured cumulus-oocyte complexes (COCs) were recovered from gonadotropin-treated donors at 24 h after LH treatment. In vitro-matured oocytes were obtained by mincing ovaries (from local veterinary clinics) and placing COCs into maturation medium for 24 h.

Birth of domestic cat kittens of predetermined sex after transfer of embryos produced by in vitro fertilization of oocytes with flow-sorted sperm.

Our goals were to: (1) determine if domestic cat sperm could be sorted to high purity by flow cytometry after overnight shipment of cooled samples; (2) evaluate the efficiency with which sorted sperm could be used to generate cat embryos in vitro; and (3) determine if live kittens of predetermined sex could be produced after transfer of embryos derived by IVF using sorted sperm. Semen samples (n=5) from one male were extended in electrolyte-free solution and shipped overnight at 4 degrees C to the sorting facility. Samples were adjusted to 75x10(6)sperm/mL and stained with Hoechst 33342.

In vitro production and transfer of cat embryos in the 21st century.

Appreciable progress has been made in the development of assisted reproductive technology (ART) for creating in vitro embryos in cats. Moreover, the extent of advancement in the last decade has been similar, albeit of more modest magnitude, to that seen in some other domestic and laboratory species, particularly when the disparities in financial, and, hence, scientific, resources are considered. The recent progress in domestic felid ART has made it possible to envisage their potential role in supporting the conservation of endangered felid species, which, in reality, is a multifarious process requiring wide-ranging, yet coordinated approaches.

In vitro embryo production and embryo transfer in domestic and non-domestic cats.

Over a 5-year interval, multiple laparoscopic oocyte retrievals were done in fishing cats (Prionailurus viverrinus), caracals (Caracal caracal) and domestic cats after ovarian stimulation with gonadotropins. From 21 retrievals in five fishing cats, 579 preovulatory oocytes (mean = 27.6) were recovered and 348 embryos were produced in vitro (mean = 16.