Is BrdU (Bromodeoxyuridine) staining performed in vivo?

Yes, BrdU (Bromodeoxyuridine) staining is performed in vivo. There are two methods used for in vivo BrdU labeling of tissues and cells – Intraperitoneal injection (IP) and oral administration. 

• In the IP method, mice are injected with a sterile solution of 10mg/ml of BrdU in PBS. BrdU can be detected in the thymus, bone marrow, and small intestine as quickly as 30 minutes after the injection. 
• In the oral administration method, BrdU is diluted to 0.8 mg/ml in drinking water. The non-invasive nature of oral administration of BrdU makes this more useful for extended BrdU administration. The downside is that it adds some amount of variability into the assay as the animal’s water consumption cannot be controlled.