Effects of the preservation medium and storage duration of domestic cat ovaries on the maturational and developmental competence of oocytes in vitro.

We examined the effectiveness of saline, Euro-Collins solution (EC), and ET-Kyoto solution (ET-K) as preservation media for the cold storage of feline ovaries. Ovaries were maintained in these media at 4°C for 24, 48, or 72 h until oocyte retrieval. The ET-K group exhibited a higher oocyte maturation rate than the saline group after 72 h of storage.

Development of feline embryos produced using freeze-dried sperm.

Freeze drying has been developed as a new sperm preservation method that eliminates the necessity of using liquid nitrogen. An advantage of freeze-dried sperm is that it can be stored at 4 °C and transported at room temperature. To develop assisted reproductive techniques (ARTs) for domestic cats, we evaluated the effect of the freeze-dry procedure on cat sperm DNA by analyzing DNA integrity (experiment 1) and by generating cat embryos using freeze-dried sperm that had been preserved for several months (experiment 2).

Feline embryo development in commercially available human media supplemented with fetal bovine serum.

Feline embryo development was examined for 7 days after fertilization using commercially available human media supplemented with 0.3% bovine serum albumin (BSA) or 5% fetal bovine serum (FBS). Cumulus-oocyte complexes were categorized as Grades 1, 2, and 3 according to morphology.

Development of feline embryos produced by Piezo-actuated intracytoplasmic sperm injection of elongated spermatids.

Piezo-actuated intracytoplasmic sperm injection (Piezo-ICSI) is used as an efficient in vitro fertilization method with various animals. With this method, elongated spermatids are collected from testicular tissues and are easier to obtain from animals that unexpectedly die than ejaculate sperm. Additionally, elongated spermatid injection often results in the development of embryos and offspring.

Generation of Footprint-Free Canine Induced Pluripotent Stem Cells Using Auto-Erasable Sendai Virus Vector.

Canine induced pluripotent stem cells (ciPSCs) can be used in regenerative medicine. However, there are no reports on the generation of genome integration-free and completely exogenous gene-silenced (footprint free) ciPSCs that are tolerant to enzymatic single-cell passage. In this study, we reprogrammed canine embryonic fibroblasts using the auto-erasable replication-defective and persistent Sendai virus vector, SeVdp(KOSM)302L, and generated two ciPSC lines.