Evaluation of Pain and Prostate Volume of Dogs Treated with Intra-prostatic Injection of Botulinum Toxin Type A

Abstract

Recently, alternative medical treatment of benign prostatic hyperplasia (BPH) using intra-prostatic injection of botulinum toxin type A (BT-A) has been reported in men and mice. However, in terms of animal welfare, it remains questionable when applied to clinical use. This study aimed at evaluating the effects of intra-prostatic injection of BT-A (Botox, Allergan, USA) in dogs. Six healthy intact males with no clinical signs of BPH received 100 units of BT-A by ultrasound-guided transabdominal intra-prostatic injection (50 units of each prostatic lobe). Pain scoring, evaluation of white blood cell counts, cortisol concentrations, and observation of urination behaviour were recorded before (24 and 12 h) and at 2, 4, 6, 12, 24, 48 and 72 h after injection. Effects of BT-A on prostate volume reduction were assessed by ultrasound scan 24 h before and on days 30, 60 and 90 after injection. This study was reviewed and approved by the Animal Committee of the university. No significant differences in pain score, inflammation condition, cortisol level and urination behaviour were observed. In addition, no significant changes in prostate volume were recorded at any time points observed after BT-A injection (p > 0.05). These findings indicated that, during 72-h after treatment, BT-A caused no acute discomfort/pain and stress to the animals. Moreover, the injection of BT-A at dosage used in this study did not affect prostatic volume in the dogs.