What should be done during a rat’s estrus? - briefly
Monitor estrus by confirming the fertile phase with vaginal cytology and schedule timed mating or experimental interventions within the 12‑hour window, while maintaining stable housing conditions and minimizing stress.
What should be done during a rat’s estrus? - in detail
During the estrous phase of a female rat, precise actions are required to ensure reliable experimental outcomes and animal welfare.
Recognition of the cycle begins with daily vaginal cytology. Collect a small vaginal lavage using saline, place the sample on a slide, and examine under a light microscope. Presence of cornified epithelial cells indicates the proestrus–estrus transition, the optimal window for intervention. Document the date, time, and cell type for each animal.
Once estrus is confirmed, implement the following procedures:
- Transfer the female to a clean, ventilated cage with minimal bedding to reduce contamination risk.
- Pair the female with a proven male for a single overnight encounter; limit exposure to 12 hours to prevent overstimulation.
- Monitor mating behavior through visual observation or infrared cameras; record the occurrence of a copulatory plug as evidence of successful copulation.
- After the mating period, return the female to a single‑housing environment to monitor gestation. Provide enrichment items that do not interfere with nesting behavior.
- Conduct a health check within 24 hours post‑mating: assess body condition, respiratory sounds, and any signs of injury. Record findings in the animal management system.
- Collect blood samples at the end of estrus for hormone analysis (e.g., estradiol, luteinizing hormone) if endocrine profiling is required. Use tail vein sampling with a 27‑gauge needle, following aseptic technique.
Data management is critical. Enter all observations—cytology results, mating timestamps, health assessments, and hormone levels—into a centralized database. Ensure entries are time‑stamped and linked to the animal’s identification tag.
When the study necessitates hormonal manipulation, administer agents (e.g., gonadotropin‑releasing hormone agonists) according to validated dosing schedules. Prepare solutions in sterile saline, inject subcutaneously, and record the exact volume and concentration delivered.
Finally, maintain environmental parameters within recommended ranges: temperature 22 ± 2 °C, humidity 45–55 %, and a 12 h light/dark cycle. Verify that cage filters are replaced weekly and that water and food supplies are uncontaminated.
Adhering to these steps guarantees accurate timing of reproductive events, minimizes variability, and upholds ethical standards throughout the estrous period.