Efficient method for transfer of microinjected eggs to mouse ampulla for generating transgenic mice

Area of Science:

• Reproductive Biology
• Surgical Techniques
• Mouse Models

Background:

• Developing efficient methods for transferring microinjected mouse eggs (MEs) is crucial for reproductive research.
• Existing methods risk damaging the surrogate mother's bursa membrane and oviduct.

Purpose of the Study:

• To present a novel, highly efficient, and minimally invasive surgical technique for transferring MEs into surrogate mice.
• To improve the survival rate of MEs and increase the production of newborn pups/founders.

Main Methods:

• A custom-assembled drill head with self-closing forceps, attached to a dissecting microscope light source, is used.
• A small, precise hole is created in a blood vessel-free area of the bursa membrane and ampulla.
• The pipet containing MEs is rapidly inserted into the ampulla, minimizing exposure time.

Main Results:

• The technique achieves a 70% success rate in producing newborn pups/founders from transferred MEs.
• The procedure causes no blood loss and leaves the infundibulum intact.
• The small surgical hole shows potential for healing before delivery, ensuring surrogate health.

Conclusions:

• This system provides a stable platform for precise instrument manipulation, enabling rapid MEs transfer.
• Minimizing insertion time significantly increases MEs survival, leading to higher pup/founder yields.
• The described method offers a safe and effective approach for assisted reproduction in mice.