A Comparative Analysis of Intratesticular Versus Intra-Epididymal Injections of Clove Essential Oil on Male Dog Sterilization.

BACKGROUND

Chemical castration offers a highly beneficial and safe alternative to surgical sterilization for stray male dogs.

OBJECTIVE

This study investigates the effectiveness of intratesticular (ITI) and intra-epididymal (IEI) injections of clove essential oil for chemical castration in male dogs as a non-surgical sterilization method.

MATERIALS AND

METHODS

Twenty-four mixed-breed male dogs were randomly assigned to four groups: two treatment groups receiving clove-oil injections (bilateral ITI or IEI) and two control groups receiving saline. Blood samples were collected on Days 0, 3, 12, 21, 30 and 40, whereas semen quality and ultrasound data were analysed at 8- and 4-day intervals, respectively, to assess testosterone levels, sperm quality and testicular and epididymal changes. Dogs were castrated on Day 40 for morphological and histological tissue evaluation.

RESULTS

Both treatment groups showed significant decreases in sperm concentration, motility and viability and increased sperm abnormalities compared to control groups (p < 0.05). ITI injection caused significantly greater testosterone decline (p < 0.005), whereas IEI treatment produced notably enlarged epididymal tail volumes (p < 0.0001). Histological evaluation demonstrated marked testicular necrosis, inflammation and fibrosis following ITI clove-oil administration, whereas IEI alterations remained mild. Ultrasound assessments confirmed altered blood flow and echogenicity consistent with reproductive tissue damage after ITI injection.

CONCLUSIONS

Clove-oil injections could provide an effective, less invasive alternative to surgical castration. ITI administration was simpler and produced permanent testicular damage, whereas IEI treatment induced mainly functional changes with minimal structural disruption by Day 40. Confirming reversibility of epididymal effects will require comprehensive long-term investigation.