Feline ovulation time after LH surge have not been defined because its LH surge is occurred by several times of coital vaginal induction and cat has relatively longer time between LH surge and ovulation compared with other mammalian species. This study was performed to investigate the feline ovulation time after LH surge that was induced by hCG injection for superovulation with PMSG. For superovulation, all cats were received an initial injection of PMSG (200 IU, i.m.) followed 80 hrs later with an injection of hCG (200 IU, i.m.). And then, sampling of both ovaries was surgically performed at each 6 different times (10, 18, 22, 26, 29, and 32 hrs) after hCG injection. Cumulus-oocyte-complexes (COCs) were collected from 2 sides of oviducts and ovaries were fixed for ovarian histology. Total 38 COCs were collected only at hCG 32 hrs and no COCs were shown at earlier 5 times. However, in the ovarian histology, corpus haemorrhagicum or corpus luteum was not shown in all groups including ovary at hCG 32 hrs that COCs were collected. In conclusion, it was suggested that feline ovulation was occurred at 29~32 hrs after LH surge and taken relatively long time for CL formation after ovulation.

Glycerol is the cryoprotectant most frequently used to freeze semen in several of species. The objective of the present study was to compare the effect of three different glycerol concentrations (4, 6 or 8%, v/v) on frozen-thawed dog sperm survival rate. Ejaculates from 9 dogs collected by digital manipulation were pooled and assessed by macroscopic and microscopic criteria. Semen was divided into 3 aliquots, which were centrifuged and the sperm pellets rediluted with first Tris-glucose-citric acid extender. After 1 h cooling at , second extender containing 4, 6 or 8% glycerol was added, respectively. The semen was loaded into 0.25 ml straws and frozen and stored in liquid nitrogen and thawed. Sperm vigor, live:dead spermatozoa ratio using HOS test, and sperm morphology using stain were evaluated. After thawing, there were no significant differences among groups in vigor, viability and morphology. In conclusion, the three glycerol concentrations (4, 6 or 8%) can be used successfully in cryopreservation of canine semen. Therefore the use of 4% glycerol in the extender has less toxic effect and reduces of freezing injuries.

This study was conducted to establish an in vitro maturation (IVM) system by selection of efficient macromolecule in the porcine in vitro production (IVP) technology. To choose the efficient macromolecules in the development of porcine embryos, the effects of 3 kinds of macromolecules (porcine serum; PS, porcine follicular fluid; pFF, and polyvinyl alcohol; PVA) supplemented in IVM media on the maturation, cleavage, and development rates to blastocyst of parthenogenetic activation (PA) and in vitro fertilization (IVF) embryos were examined. The maturation rates of porcine oocytes in media supplemented with PS were significantly higher than those with pFF and PVA (92.4% vs. 85.4%, 77.1%; p<0.05). In the cleavage and development to blastocyst rates, supplement with PS or pFF in the IVM media was more effective than PA. However, there were no significant differences in cleavage and development to blastocyst between PS and pFF group. From the results of this study, it was demonstrated that PS was optimal macromolecule in the porcine IVM media.