Neutering is not associated with early-onset urethral obstruction in cats.

Objectives: The purpose of this study was to evaluate the correlation between clinical aspects and urethral lesions with reproductive status and age at neutering in obstructed male cats.
Methods: All cats with compatible signs of urethral obstruction (UO) treated at the Veterinary Hospital of the Federal Rural University of Pernambuco from 2019 to 2021 were divided into three groups according to their reproductive status: intact; prepubertal neutered; and post-pubertal neutered. Cats with compatible signs of UO were selected for further analysis. Age, clinical signs, age at neutering and age of the first obstructive event were documented. Cats with recurrent obstructive urinary signs or urethral trauma that made catheterization impossible were referred for perineal urethrostomy. The morphology of the excised penises was assessed by histopathological analysis.
Results: Of 84 cats with signs of UO included in this study, 28.6% were classified as intact, 28.6% as prepubertal neutered and 42.8% as post-pubertal neutered. Intact cats had a significantly earlier onset of UO compared with prepubertal and post-pubertal neutered cats, as seen by the age at obstruction (3.6 vs 5.7 and 5.5 years, respectively). Similar clinical signs and histopathological lesions were observed in all groups. The main clinical signs observed were stranguria, hematuria and pollakiuria. All cats had some degree of injury in the penile urethra. The most common lesions were hemorrhage, fibrosis and congestion.
Conclusions and Relevance: It appears that intact cats had an earlier onset of UO than neutered cats, regardless of age at neutering. Urethral histopathological lesions and clinical signs were similar in both groups. Pediatric neutering represents a useful tool in the control of abandoned and stray animals and the consequent dissemination of zoonoses, thus having a positive impact on public health.