title: Evaluation of intratesticular injection of glycerol for nonsurgical sterilization of dogs.
abstract: OBJECTIVE
  To determine efficacy of intratesticular injection of glycerol as a means to sterilize dogs.
  
  
  METHODS
  Six 2- to 4-year-old sexually intact male dogs.
  
  
  METHODS
  Testicular volume, serum testosterone concentration, and number of sperm in ejaculate were determined before and at weekly intervals for 12 weeks following intratesticular injection of a 70% glycerol solution (1 ml/testis). Testicular tissue specimens for histologic evaluation were obtained 4, 8, and 12 weeks following injection.
  
  
  RESULTS
  Number of sperm in ejaculate following glycerol injection was not significantly different from number before injection. Compared with preinjection values, serum testosterone concentrations were significantly less 5, 9, and 10 weeks following injection, although libido and ejaculate characteristics were unchanged. Testicular swelling was evident 24 to 48 hours following injection, and testicular volume decreased starting on week 5 following treatment. Seminiferous tubules and evidence of normal spermatogenesis were detected in testicular biopsy specimens obtained from all dogs 12 weeks following injection.
  
  
  CONCLUSIONS
  Intratesticular injection of a 70% glycerol solution did not result in azoospermia and sterility in dogs.
authors.affiliation: Theriogenology Area, College of Veterinary Medicine, The Ohio State University, Columbus 43210, USA.
authors.forename: H M
authors.initials: HM
authors.lastname: Immegart
authors.forename: W R
authors.initials: WR
authors.lastname: Threlfall
mesh_terms: D000818:Animals; D001706:Biopsy / Q000662:veterinary; D004285:Dogs / Q000502:physiology*; D005990:Glycerol / Q000008:administration & dosage / Q000494:pharmacology*; D007267:Injections / Q000662:veterinary; D008297:Male; D009919:Orchiectomy / Q000379:methods / Q000662:veterinary*; D011863:Radioimmunoassay / Q000662:veterinary; D012661:Semen / Q000502:physiology; D013076:Sperm Count / Q000662:veterinary; D013245:Sterilization, Reproductive / Q000379:methods / Q000662:veterinary*; D013737:Testis / Q000000981:diagnostic imaging / Q000187:drug effects / Q000502:physiology*; D013739:Testosterone / Q000097:blood; D014463:Ultrasonography
chemical_list: D013739:Testosterone; D005990:Glycerol