Responsiveness of rabbits to superovulation treatment by a single injection of follicle-stimulating hormone with aluminum hydroxide gel

Aluminum hydroxide gel (Al‐gel), which is used as an adjuvant, can absorb macromolecules. We investigated the applicability of Al‐gel to the sustained release of follicle‐stimulating hormone (FSH) as a simplified method of superovulation (SOV) in rabbits. The responsiveness of rabbits to SOV by a single injection of FSH dissolved in Al‐gel suspension (3.2 mg Al/ml) and in 10% (w/v) polyvinylpyrrolidone (PVP), and by multiple injections of FSH in saline was examined. The numbers of total and fertilized eggs recovered from rabbits treated with FSH in Al‐gel (40.5 and 26.3, respectively) were similar to multiple injections (47.4 and 28.6, respectively) and were significantly greater (P