Please review these studies before you apply: 

Titer Testing VS Traditional Vaccine Schedule: Titer Tests for Dogs | PetMD 

UC Davis Golden Retriever Spay/Neuter Study: Golden retriever study suggests neutering affects dog health | UC Davis 

Dr. Karen Becker Spay/Neuter Video:  Dr Becker Discusses the Importance of Canine Hormone Support

Benefits and negative side effects of spay/neuter: Assisting Decision-Making on Age of Neutering for 35 Breeds of Dogs