Live pups from evaporatively dried mouse sperm stored at ambient temperature for up to 2 years.

The purpose of this study is to develop a mouse sperm preservation method based on evaporative drying. Mouse sperm were evaporatively dried and stored at 4°C and ambient temperature for 3 months to 2 years. Upon rehydration, a single sperm was injected into a mature oocyte to develop into a blastocyst after culture or a live birth after embryo transfer to a recipient female.

Technical note: Mice produced by intracytoplasmic sperm injection using a modified conventional method.

A piezo-driven pipette that includes a small amount of mercury to enhance efficiency is widely used for mouse intracytoplasmic sperm injection (ICSI). Unfortunately, the use of toxic mercury is not permitted in hospital facilities and alternatives to mercury that enhance performance of the device do not work as well in the mouse. We have eliminated mercury toxicity and obtained acceptable ICSI efficiency using a modified conventional method.

Preservation of mouse sperm by convective drying and storing in 3-O-methyl-D-glucose.

With the fast advancement in the genetics and bio-medical fields, the vast number of valuable transgenic and rare genetic mouse models need to be preserved. Preservation of mouse sperm by convective drying and subsequent storing at above freezing temperatures could dramatically reduce the cost and facilitate shipping. Mouse sperm were convectively dried under nitrogen gas in the Na-EGTA solution containing 100 mmol/L 3-O-methyl-D-glucose and stored in LiCl sorption jars (Relative Humidity, RH, 12%) at 4°C and 22°C for up to one year.

One-step versus two-step culture of mouse preimplantation embryos: is there a difference?

Background: A comparison has been made of the development of mouse zygotes in either one-step or two-step culture systems.

Methods: Embryo culture, blastocyst cell counts and embryo transfer were done.

Results: No significant differences were observed in the proportions of blastocysts, rates of hatching, numbers of cells in the inner cell mass (ICM) and trophectoderm (TE) that developed in protocols: one-step culture in potassium-enriched simplex optimized medium supplemented with glucose and amino acids (KSOMg(AA)), two-step culture in KSOMg(AA)/KSOMg(AA), and two-step culture in G1.

Mouse sperm desiccated and stored in trehalose medium without freezing.

Mouse sperm with and without trehalose were desiccated under nitrogen gas and stored at 4 degrees C and 22 degrees C. After rehydration, sperm were injected into oocytes using intracytoplasmic sperm injection and embryonic development was followed. Sperm were dried for 5.