Our mouse & rat line rescue services can provide an opportunity for you to recover a line of animals that is no longer productive. We have extensive experience working with genetically engineered rodents that are suffering from sub-par fertility due to age, body condition, or other adverse phenotype. Each line that is entered into our rescue program is managed by a dedicated project manager who works closely with an embryology specialist to determine the cause of the sub-fertility and work with you to develop a solution. This individual will be your primary point of contact and can assist you in every step of the process.
The first step to rescuing your line is to determine the cause of the reduced or absent breeding performance. At Charles River, we have a variety of tools at our disposal to accomplish this task including:
- Superovulation followed by oocyte collection and analysis to determine female fertility
- Computerized sperm analysis to determine male fertility
- Observational mating to determine copulation ability
- Ultrasound imaging to determine embryo viability at various stages
Once the cause and severity of the fertility problem has been assessed, we have several services specifically designed to overcome the issue, including:
- Foster Nursing
This rescue option is utilized for lines where females are unable or unwilling to care for and/or nurse their pups. We utilize outbred foster moms with a different coat color than your animals to boost the number of offspring that can be fostered and guarantee which pups are genetically engineered.
- Ovarian transplantation
This rescue option is often utilized for lines where the females are no longer capable of carrying a litter to term or are unable to breed due to age or poor body condition. This option is valuable for colonies that only have a few nonproductive females remaining.
- Laser-assisted in vitro fertilization (IVF)
This rescue option is utilized for lines that have males with poor sperm quality. By utilizing a XYCloneTM laser to create two to three holes in the zona pellucida of donor oocytes, fertilization is enhanced.
- Intracytoplasmic Sperm Injection (ICSI)
This rescue option is utilized to rescue lines that have males with extremely low sperm concentration or no motility. This is typically used as a last resort for highly valuable lines after all other attempts have failed.
To find our more about our rescue options, get pricing, or initiate a project, please contact us at gems@crl.com.