Laparotomic Approach for Collecting Serial Hepatic Biopsies in Rats (Rattus norvegicus) and Mice (Mus musculus).

Area of Science:

• Veterinary Medicine
• Surgical Techniques
• Rodent Models

Background:

• Laboratory animal veterinarians are frequently consulted to refine research protocols.
• Assessing cellular-level processes often requires repeated tissue sampling.
• Developing minimally invasive techniques is crucial for animal welfare and data integrity.

Purpose of the Study:

• To develop and evaluate a novel surgical approach for serial liver biopsies in rats (Rattus norvegicus).
• To assess the impact of multiple survival surgical procedures on rodent weight and survival rates.
• To determine if rodent survival following serial liver biopsies is independent of weight fluctuations.

Main Methods:

• A novel surgical technique involving laparotomy and disposable biopsy punches was developed for serial liver sampling.
• The procedure was performed on rats (Rattus norvegicus) at three different time points.
• A pilot study was conducted in mice (Mus musculus) using the same methodology.

Main Results:

• The novel method allowed for serial liver biopsies in rodents.
• Rodent survival rates were statistically significant when comparing different strains (Belgrade rats vs. Sprague Dawley rats and Swiss Webster mice).
• Survival outcomes were independent of the weight loss or gain experienced by the animals during the study.

Conclusions:

• Multiple laparotomies and liver biopsies can be performed on rodents with a survival rate independent of weight changes.
• The developed technique provides a viable method for serial liver tissue collection in research settings.
• This approach supports robust scientific inquiry while considering animal welfare in rodent models.