Prostatic diseases including benign prostatic hyperplasia, prostatitis, and prostatic cysts are common welfare problems in entire male dogs that can be largely prevented by castration.
Prostatic disease causes significant welfare suffering — the discomfort of difficult defecation from a large prostate compressing the rectum, painful urination from urethral pressure, and the systemic illness of acute prostatitis are all sources of genuine distress. The relationship between intact male status and prostatic disease is so strong that prostatic conditions are rare in castrated males. The welfare argument for castration in dogs not intended for breeding is therefore partly preventive — avoiding the near-universal development of BPH and its associated welfare complications. Acute bacterial prostatitis is a particularly severe welfare emergency requiring immediate antibiotic treatment and analgesia alongside castration once the acute infection is controlled.