Animal Reproduction (AR)
https://animal-reproduction.org/article/doi/10.1590/1984-3143-AR2025-0125
Animal Reproduction (AR)
REVIEW ARTICLE

Exploring behavioral outcomes of gonadectomy in pets: a need for personalized approaches

Fabiano Borba Guimarães; Renata Oliveira Barreto; Maricy Apparício

http://dx.doi.org/10.1590/1984-3143-AR2025-0125 Anim Reprod, vol.23, n3, e20250125, 2026
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Abstract

Gonadectomy, the surgical removal of reproductive organs—is commonly practiced in canine management and is often associated with responsible pet ownership. Although advised for preventing unwanted litter and specific health hazards, its effects on canine behavior remain contentious and little studied. This article analyzes the physiological and behavioral effects of gonadectomy in dogs, emphasizing other sexually dimorphic behaviors including mounting, wandering, and urine marking, alongside aggression, fear, anxiety, separation-related issues, and canine cognitive dysfunction. Gonadectomy impacts hormonal equilibrium by modifying the hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes, hence affecting stress responses, cognition, and behavior. Certain research indicates that neutering diminishes urine marking and roaming; nevertheless, the results are inconsistent. Conflicting research suggests that gonadectomy may intensify aggression, fearfulness, and anxiety, thus undermining the human-animal bond. The effects of gonadectomy on cognitive impairment remain ambiguous. Alternative methods, including vasectomy, ovary-sparing spay, and chemical castration, provide reproductive regulation while maintaining hormonal function, potentially alleviating negative behavioral consequences. Due to the complex aspects of behavioral development, encompassing heredity, environment, and personal experiences, a general policy on gonadectomy is unsuitable. This review highlights the necessity of personalized assessments when advising gonadectomy for behavioral management in canines. Veterinarians must meticulously evaluate the advantages and disadvantages, considering the unique circumstances of each animal and seeking guidance from veterinary behaviorists, as necessary. Routine desexing should not be universally advocated only for the purpose of mitigating behavioral issues. Additional research is crucial to comprehend the intricate link between gonadectomy and canine behavior.

Keywords

castration, spay, canine, animal welfare, physiology, hypothalamic-pituitary-adrenal axis

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Submitted date:
08/28/2025

Accepted date:
03/04/2026

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