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Animals
  • Article
  • Open Access

6 November 2025

Development of an Operational Protocol for Animal Hoarding: A Conceptual Proposal Based on Multidisciplinary Field Experience

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1
Local Health Authority Rome 1, 00193 Rome, Italy
2
Private Practice, 00137 Rome, Italy
3
Local Health Authority Rome 4, 00053 Civitavecchia, Italy
4
Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900 Lodi, Italy
This article belongs to the Section Public Policy, Politics and Law

Simple Summary

Animal hoarding is a complex and often under-recognized form of neglect, characterized by the accumulation of a large number of animals without ensuring adequate care, hygiene, or living conditions. This study underscores the need for a structured and multidisciplinary approach that integrates veterinary, psychological, and social perspectives. Drawing on field experience and literature review, we propose an operational framework for the assessment and management of animal hoarding cases, emphasizing the importance of early intervention and coordinated professional collaboration to protect both human and animal welfare.

Abstract

Animal hoarding is a complex and multifactorial phenomenon that poses serious risks to animal welfare, public health, and environmental balance. Despite increasing attention, current interventions often remain fragmented and lack integration across medical, psychological, and social domains. Based on a critical review of existing tools and field experience in the Italian context, this study proposes a structured operational protocol to support multidisciplinary teams in the assessment and management of animal hoarding cases. The protocol integrates three complementary tools: a preliminary observational form, a clinical-relational interview, and a veterinary health form. Designed to be modular, replicable, and shareable among professionals from diverse backgrounds, the protocol aims to promote a One Welfare approach, recognizing the systemic interconnection between animal suffering, human psychological distress, and environmental degradation. While further experimental validation is required, this conceptual model provides a concrete operational basis for structured interventions and consistent data collection in support of research and public health.

1. Introduction

Animal hoarding (AH) is a complex condition with profound implications for animal welfare, public and mental health, and environmental safety [1]. Although internationally recognized as a severe manifestation of Hoarding Disorder (HD), as defined in the DSM-5 [2], it represents a global issue documented across diverse cultural and socio-economic contexts. However, the phenomenon remains largely overlooked in Italy and lacks a systematic framework, despite a steady increase in reports from health services and public safety authorities.
The literature has documented the main psychopathological features of AH, as well as its environmental and health-related consequences [3,4,5]. However, shared tools are still lacking for collecting and connecting relevant information—ranging from the living conditions of animals and the environment, to the subjective experiences of the individuals involved, to the social impact and post-intervention outcomes [6]. Crucial data—such as the fate of removed animals, the evolution of living conditions, the long-term effectiveness of interventions, and recurrence rates—remain fragmented or entirely unavailable [7,8]. In many cases, denial of the problem and dysfunctional attachment to animals hinder effective care and intervention efforts [9].
The Italian operational context involves numerous stakeholders—veterinary services, mental health services, law enforcement, social services, and public health authorities—who often lack structured coordination [10]. In this scenario, there is an urgent need for tools that can overcome the current fragmentation and enable an integrated understanding of the phenomenon, guiding assessments, interventions, and follow-up in alignment with the regulatory framework.
This study proposes a conceptual methodological framework for managing animal hoarding (AH) cases, developed through the analysis of critical issues encountered during the application of an adapted observational tool, the Case Report Form [10], to 48 documented cases in the Lazio region between 2019 and 2024. The proposed model integrates objective assessments of environmental and veterinary conditions with psychological and relational exploration tools, which are currently lacking in existing approaches.
Although grounded in theoretical foundations and tested through simulation, the protocol represents a well-structured and rational preliminary model designed to address current methodological gaps in animal hoarding management. It serves as a starting point for the development of a validated tool that will require verification in terms of reliability, inter-rater consistency, and practical applicability in real-world settings.
The following sections outline the legal and psychopathological context that forms the theoretical and operational basis of this framework.

3. Psychopathological Framework of Animal Hoarding: Implications for Operational Management

Animal hoarding (AH), although recognized in the DSM-5 as a specific manifestation of Hoarding Disorder (HD), presents distinctive clinical and relational features. Individuals who hoard animals frequently accumulate objects as well [16]; however, the core pathological element remains the hoarding of animals, driven by unique emotional dynamics centered on perceived caregiving, rescue missions, or deep attachment bonds that are qualitatively different from those underlying object hoarding [10,13,14]. Direct field observations have highlighted the central role of psychopathology in effectively understanding and managing AH. The condition frequently coexists with other major psychiatric conditions, such as psychosis or neurocognitive disorders [12,24,25].
Operational experience gained in Italian contexts, supported by scientific literature [12,14,24,26,27,28], points to the recurrent presence of four main clinical profiles. While not always formally diagnosable during urgent interventions, these patterns are crucial for guiding field-based management strategies:
Obsessive–Compulsive Disorder (OCD)
In these cases, hoarding presents as an egodystonic compulsion—that is, perceived as inconsistent with the individual’s core values—driven by intrusive thoughts of rescue or protection. Awareness of the animals’ suffering and personal distress typically makes these individuals more open to collaboration [12,28]. Often associated with the “overwhelmed caregiver” profile, they recognize their own limitations in managing the situation, albeit with significant feelings of guilt.
Obsessive-Compulsive Personality Disorder (OCPD)
Marked by rigid thinking, perfectionism, and excessive rationalization, this condition leads to egosyntonic behaviors (perceived as consistent with the individual’s identity). These individuals, often identified as “rescuers,” interpret hoarding as an ethical mission and resist any external intervention perceived as a threat [29]. Effective engagement requires a gradual construction of trust and rapport.
Psychosis
In cases involving psychosis, hoarding behavior is driven by structured delusions (e.g., beliefs of spiritual connection with animals), with a marked impairment of reality testing [24]. Intervention in such contexts requires the involvement of mental health professionals to address delusional content, often associated with the profiles of the “exploiter” or the delusional “rescuer”.
Schizophrenia
This condition represents one of the most severe clinical associations with AH. Hoarding behavior is disorganized, impulsive, and devoid of conscious purpose, accompanied by widespread impairment in managing both the environment and the animals. The home environment is often found in extreme conditions, incompatible with human and animal life. Individuals typically exhibit the profile of a disorganized “exploiter” and require structured, and sometimes coercive, interventions along with long-term psychiatric care [27,30].
In addition to this clinical classification, the conceptual model proposed herein introduces a behavioral typology of hoarders, designed to guide operational strategies and support the development of a shared professional vocabulary. The profiles described in Table 1—derived from the integration of bibliographic sources [13,31,32] and field observations—offer a pragmatic framework for interpreting relational patterns with animals and tailoring intervention approaches accordingly. While the behavioral characteristics and levels of awareness are well documented in the literature, the operational suggestions outlined in Table 1 reflect a synthesis of clinical experience and multidisciplinary field practice.
Table 1. Behavioral profiles in animal hoarding: operational implications. Behavioral profiles of animal hoarders, adapted from Patronek et al. [13], Reinisch [6], and the Frost et al. [31]. All descriptions have been reformulated by the authors and integrated with an additional column (Operational Recommendations) based on field experience. The terminology of behavioral profiles follows standard usage in the scientific literature on animal hoarding.

4. Materials and Methods

4.1. Objectives and Methodological Rationale

This study aims to critically assess the applicability and limitations of the modified observational tool derived from the Case Report Form developed by HARC [5], as used for data collection in cases of animal hoarding within the Italian context. The ultimate objective is to determine whether this tool is suitable to support an integrated multidisciplinary response. If not, the findings would justify the development of a new conceptual protocol tailored to the complexity of the phenomenon.

4.2. Description of the Tool Used

The observational tool employed in this study originates from the Case Report Form initially developed by Patronek and later adapted by HARC [9], with additional adaptations to meet the operational requirements of the Italian context. It includes approximately 90 items organized into 20 thematic sections. Specifically, the form addresses areas such as the subject’s demographic information and household composition, the condition of the dwelling and the level of environmental degradation, the presence and health status of animals, the methods by which they were acquired, the accumulation of objects and waste leading to spatial impairment, the individual’s declared motivations, relational dynamics, and the outcomes of the intervention.
The response options are structured through yes/no questions, ordinal scales measuring severity (e.g., from “none” to “severe”), and standardized checklists. However, the tool lacks validated psychometric instruments and does not contain sections specifically designed for relational or psychopathological assessment.

4.3. Data Collection Methods

The adapted Case Report Form was applied to 48 documented cases managed between 2019 and 2024 by the Local Health Units ASL Roma 1 and ASL Roma 4, following reports of hygiene violations, suspected animal mistreatment, or environmental degradation. The sources reviewed included veterinary clinical records, official inspection reports, internal ASL documentation, and reports from law enforcement and social services.
These cases were selected because they fulfilled the diagnostic and behavioral criteria for animal hoarding, as defined in the DSM-5, and were confirmed through multidisciplinary assessment involving veterinary, social, and law enforcement professionals. Data collection was conducted by public veterinary officers and healthcare professionals during or after the intervention. Inclusion criteria were based on the definition of an animal hoarder provided by Patronek [9]: a person who has accumulated a large number of animals and is unable to provide them with the minimum standards of nutrition, hygiene, and veterinary care; who fails to act despite the animals’ progressive deterioration (including illness, malnutrition or death) and the degradation of the surrounding environment (severe overcrowding and unsanitary conditions); and who does not recognize the negative consequences of their behavior on their own health or on the well-being of other household members. The data were analyzed using a qualitative synthesis approach aimed at identifying recurrent clinical, relational, and environmental patterns.

4.4. Data Analysis

The data, originally collected using paper forms, were transcribed into an electronic spreadsheet (Excel) and analyzed in aggregate form, in full compliance with the European General Data Protection Regulation (GDPR, Regulation EU 2016/679), ensuring that no identifying information was included. A descriptive analysis of the data was carried out by calculating the completion rate for each thematic area. Sections containing partial or incomplete information were classified as critical. No inferential statistical analyses were conducted, as the study focused on assessing the suitability of the tool for the Italian context, with exploratory, prospective, and analytical objectives.

5. Results

The field application of the observational tool adapted from the Case Report Form revealed a range of heterogeneous outcomes in terms of operational effectiveness and informational completeness. Overall, the forms were partially—but still meaningfully—completed in approximately 70% of the cases, showing good performance in capturing structural data such as the number of animals present, the hygienic and sanitary conditions of the environment, and the general state of housing degradation.
However, core dimensions essential for a multidimensional care approach—such as the underlying motivation for accumulation, the emotional attachment to the animals, and the individual’s awareness of the situation—were often found to be incomplete, overly generic, or not feasible to assess.
In several cases, for instance, the question regarding “stated motivations” elicited stereotyped responses (e.g., “I’m saving them”, “I can’t abandon them”), lacking clinical depth and difficult to categorize meaningfully. Other sections—such as those addressing family dynamics or previous attempts at intervention—were often incomplete or insufficiently detailed, thus compromising their interpretability.
The veterinary component, although formally included, was generally limited to broad assessments (e.g., “undernourished animals”, “presence of disease”) without the use of validated clinical scales or standardized criteria for evaluating and reporting animal welfare. This approach made it impossible to consistently compare different cases and hindered the integration of data concerning animal health, environmental conditions, and the relational functioning of the individual.
Moreover, the generic nature of the available assessments does not support reliable use in legal contexts, nor does it provide an adequate basis for long-term monitoring or the planning of structured follow-up interventions.
In 21 out of 48 cases (43.7%), voluntary follow-up interviews were conducted; however, the information gathered was not systematically integrated into the tool, resulting in discontinuous observation over time.
The estimated completeness and main critical issues identified across the assessed domains are summarized in Table 2.
Table 2. Assessment of key dimensions based on the adapted Case Report Form: estimated completeness and critical issues. Summary of the estimated completeness and main critical issues observed in each area assessed by the adapted Case Report Form. Percentages are approximate and based on the qualitative analysis of completed forms (n = 48).

5.1. Operational Limitations Encountered

Health and social care professionals reported a series of recurring challenges. First, ambiguities or overlaps among items made it difficult to maintain consistency during completion. Second, there was a lack of shared criteria for interpreting and using the data across professionals from different backgrounds, such as veterinarians, psychologists, and social workers. Third, the form proved inadequate as a decision-making tool, as it lacked indicators to assess urgency, risk, priority, or the effectiveness of interventions.
While the tool served as a useful initial descriptive framework, it presented several structural and functional limitations that constrain its use as an integrated operational support in the practical management of cases.

5.2. Implications and Rationale for the New Protocol

These observations, which emerged consistently from the analysis of 48 real-life cases, led to the development of a new integrated conceptual model that better reflects the complexity of the phenomenon and addresses three main needs: first, a relational and psychological understanding of the individual engaging in animal hoarding, achieved through a clinical-relational interview; second, an integrated multidimensional assessment encompassing the living environment, physical health, social network, and animal welfare; and third, longitudinal monitoring, with the possibility of updating and comparing cases over time.
The proposed protocol is designed to be dynamic, interdisciplinary, and replicable. It aims to guide initial assessment, intervention planning, and long-term monitoring. A simulated case illustrating its practical application is included in the Supplementary Materials (Files S4–S6) as an example of operational implementation.

6. Discussion

The retrospective analysis of a modified observational form—derived from the Case Report Form developed by HARC [5]—applied to 48 real-life cases managed by two local health authorities (ASLs) in the Lazio region between 2019 and 2024, revealed that the tool only partially supports a multidisciplinary and integrated approach to animal hoarding (AH).
While the form proved effective in collecting basic structural data—such as the number of animals and the hygienic-sanitary conditions of the environment, which are essential for immediate intervention—it was less efficient in addressing key dimensions required for a holistic understanding and long-term management of the phenomenon. Specifically, the form lacks a systematic approach to important aspects such as the subjective motivations behind accumulation, the individual’s level of awareness, family and relational dynamics, the nature of the emotional bonds with animals, and the assessment of relapse risk. These dimensions were either absent or addressed in a generic and unstructured manner.
In our sample, psychological and relational areas were particularly underrepresented, with an average completion rate of less than 20%. Similarly, although veterinary data were present, they lacked standardization and clinical detail, making it difficult to evaluate each case individually or compare across cases. This also hindered full integration with environmental or relational analyses. These findings are consistent with operational challenges reported in other studies, which emphasize the need for more robust tools to address the complexity of AH [7,33,34,35].
Another critical issue was the absence of dedicated follow-up sections, which made it impossible to document case evolution or detect early signs of relapse. This discontinuity in data collection compromised the ability to build a cumulative and longitudinal framework, essential for guiding personalized interventions and assessing their long-term effectiveness [8,16].
In practice, the professionals involved encountered difficulties using the form as an operational support tool, citing ambiguities in the items, interpretative complexity, and a general lack of coordination among the different professional roles. This often resulted in fragmented and reactive responses, rather than proactive and coordinated case management.
In this context, the aim of the present study was not to analyze in detail the specific features of the 48 cases, but rather to critically assess the tool through the lens of practical experience in managing them. The consistency and recurrence of the issues encountered underscored the need for a new observational protocol capable of integrating environmental, health, psychological, relational, and follow-up dimensions in an organized and comparable manner. The evidence presented here highlights the critical need for operational tools to support the management of animal hoarding—not only to ensure animal welfare, but also to protect public health and support vulnerable individuals. While animal hoarding shares roots with broader failures in mental healthcare, it differs fundamentally from other untreated psychiatric conditions because its impact extends far beyond the affected individual, creating immediate risks for animals, neighbors, and community health. Unlike depression, anxiety, or object hoarding, animal hoarding cannot be addressed through clinical care alone—it requires coordinated intervention across veterinary, social, legal, and public health domains [10,17,35].
The protocol proposed in this study is designed to operationalize this cross-sectoral approach, providing a conceptual, structured, and replicable tool to guide data collection, risk assessment, and multidisciplinary intervention planning in complex AH cases. However, it will be essential to subject the protocol to future experimental validations, including reproducibility testing, inter-rater reliability, and predictive value with respect to relapse risk. Only through these steps can it achieve full clinical and decision-making validity.
While the present study focuses on cases from a geographically limited area (ASL Roma 1 and ASL Roma 4), the clinical and behavioral patterns observed are consistent with findings reported in the international literature across diverse geographical contexts, including Brazil [7], Portugal [32], England [36], and other countries [35]. Available evidence suggests that animal hoarding occurs with similar prevalence (2–6%) across the United States and Europe [35], and that the core psychopathological and relational dynamics remain relatively stable across different geographical and cultural contexts, with variation primarily occurring in the types of animals accumulated rather than in the fundamental characteristics of the disorder [16,35]. However, further systematic research is needed to explore potential differences in animal hoarding manifestation between Italian regions and between urban and rural settings.

7. The Multidisciplinary Operational Protocol for Animal Hoarding: Structure and Application

7.1. Conceptual Framework and Aims

Following the identification of key limitations in the use of current operational tools within the Italian context—and informed by extensive practical experience in managing animal hoarding (AH) cases—a new integrated protocol was developed. AH is a condition involving intertwined health, psychological, and social factors, extending far beyond hygienic concerns and often rooted in complex psychosocial suffering and relational disruption [17,36,37]. Therefore, any effective approach must balance medical, psychosocial, and legal priorities, while maintaining a strong focus on the care and dignity of both individuals and animals.
Although this protocol represents a preliminary, conceptual tool not yet validated in the field, it has been designed to provide a structured foundation for future experimental applications. It offers a shared and adaptable framework for intervention, applicable across different territorial contexts.

7.2. Tools of the Protocol

The proposed protocol is composed of three integrated tools designed to facilitate collaboration among the various professionals involved, promote a truly multidisciplinary approach, and ensure a continuous and structured care process based on clinical criteria. These tools are:
Preliminary Observational Form (POF)
A rapid screening instrument is to be completed during the initial visit by healthcare professionals, social workers, or law enforcement officers. It allows for the collection of preliminary information on the living environment, number and species of animals, hygienic conditions, and the individual’s openness to dialog. Its observational structure provides an objective basis for deciding whether to initiate a more in-depth assessment process. Estimated completion time: 10–15 min.
Clinical-Relational Interview for Animal Hoarding (ICRAH) (The acronym ICRAH derives from the original Italian name: “Intervista Clinico-Relazionale per l’Animal Hoarding”).
This tool explores the individual’s psychological and relational functioning, perception of the situation, emotional attachment to animals, past experiences, and readiness for change. It is organized into thematic sections with open-ended questions and scoring criteria ranging from 1 to 3 for each domain assessed (e.g., awareness, risk, cooperation). It can be administered in different phases by psychologists, or by social workers and veterinarians with specific relational training. Average administration time: 30–40 min.
Veterinary Health Record for Animals in Hoarding Contexts (VHR—AH)
A clinical tool completed exclusively by veterinarians, aimed at the standardized assessment of the physical, behavioral, health, and housing conditions of the animals present. It includes specific indicators (e.g., nutritional status, presence of lesions) based on the AWIN (Animal Welfare Indicators) approach and provides official documentation suitable for technical, health-related, and legal purposes. Estimated completion time is 5–10 min per representative animal.
All tools are designed to be used in a modular fashion, depending on the severity of the case, the availability of the professionals involved, and the composition of the interdisciplinary team. The forms are available in the Supplementary Materials (Files S1–S3).
These three tools, which differ in scope, duration, and professional requirements, are designed to be applied flexibly depending on the context. Their main features are summarized in Table 3.
Table 3. Protocol Toolset Overview. Summary of the three integrated tools included in the proposed operational protocol for animal hoarding cases, detailing their purpose, target professionals, and estimated completion times. Tools are intended to be applied in a modular and flexible manner depending on case severity and team composition.

7.3. Operational Phases of the Protocol

The protocol is structured into four sequential phases, guiding the multidisciplinary team through the entire intervention process:
Reporting
The process begins with the collection of preliminary information from formal sources (local health authorities, law enforcement, social services) or informal channels. It is essential to assess the reliability of the source, the presence of critical elements (e.g., odors, noise, visible animals), and the urgency of the intervention.
On-Site Inspection
Carried out by public service veterinarians, often accompanied by law enforcement officers to ensure safety and legal access to the premises. During the inspection, an initial clinical evaluation of the animals is conducted, alongside an environmental and hygienic assessment of the living space. If particularly critical conditions are identified—such as extreme degradation, risks to minors or vulnerable individuals, or signs suggestive of psychiatric disorders—the multidisciplinary team is immediately activated. At this stage, the Preliminary Observational Form (POF) is used to provide an initial and concise assessment of the severity of the situation.
Case Management
Based on the information collected and the preliminary assessment, the team develops a personalized intervention plan. This may include psychological support, education on responsible ownership, reproductive control, and health and environmental interventions. The approach is tailored to the psychological profile of the individual, available resources, and the condition of the animals and environment. The ICRAH—Clinical-Relational Interview for Animal Hoarding—is fully applied during this phase. It may be administered over multiple sessions by professionals with relational training and contributes to building a shared understanding that informs the intervention plan. At the same time, the Veterinary Health Record (VHR) is completed to document not only the health status of the animals—focusing on widespread pathological conditions, malnutrition, behavioral issues, and uncontrolled reproduction—but also the condition of the surrounding environment.
Monitoring
This phase is essential for preventing relapse, which according to the literature occurs at rates approaching 100% [8,35,38]. Monitoring includes scheduled follow-up visits, updates to the previously completed forms, and additional evaluations if necessary. The POF, ICRAH, and VHR are revisited at later stages to document the evolution of the case and the effectiveness of the implemented measures. To ensure long-term effectiveness, the establishment of a specialized service with the stable presence of various professionals (veterinarians, psychotherapists, psychiatrists, social workers) is strongly recommended.
A visual summary of the four phases, including main activities, professional roles, and related tools, is presented in Figure 1.
Figure 1. Operational flowchart of the multidisciplinary protocol. Visual representation of the four sequential phases of the proposed protocol for animal hoarding cases. The diagram outlines the key activities, professional roles, and operational tools associated with each phase: reporting, on-site inspection, case management, and monitoring.

7.4. Roles and Approaches of the Multidisciplinary Team

The effective management of animal hoarding (AH) cases relies on stable and coordinated collaboration among professionals from multiple disciplines. Each team member contributes a unique perspective and set of skills essential to managing the clinical, social, legal, and environmental complexities involved [38].
Veterinarians are often the first to interact with the hoarder. In addition to conducting clinical assessments of animal health and welfare, they frequently detect signs of neglect—intentional or not—and play a critical role in building trust with the individual. They also serve as institutional mediators, facilitating coordination among stakeholders [39,40].
Psychiatrists and psychotherapists are responsible for identifying potential comorbid mental health disorders and establishing appropriate therapeutic pathways [34,41].
Social Workers focus on restoring habitable living conditions, supporting everyday functioning, and activating local welfare and care networks.
Law Enforcement Officers ensure safe, lawful access to the premises and support intervention logistics.
Public Health Services assess environmental health risks and contribute to the management of hygiene and sanitation issues [16].
Once the team is formed, the intervention strategies must be adapted to the specific psychological and relational profiles of the individual. As described in Section 3, the approach varies depending on the subject’s level of awareness, emotional attachment to animals, and any underlying psychiatric conditions. For instance, “caregivers” tend to respond positively to structured support, while individuals with psychotic disorders may strongly resist any form of intervention.
Table 4 summarizes the operational strategies associated with four recurring psychopathological profiles observed in the field. These are not formal diagnoses but practical behavioral typologies intended to support real-world decision-making.
Table 4. Psychopathological profiles and corresponding operational strategies. These profiles do not constitute formal psychiatric diagnoses but are field-derived categories observed by professionals in multidisciplinary interventions.
These recommendations underscore the need for flexible, evidence-based, and compassionate approaches, tailored to the vulnerabilities and potential for recovery of each individual.

7.5. Application Perspectives and Future Validation

The proposed protocol is part of an ongoing exploratory project. Its effectiveness, sustainability, and replicability will need to be assessed through future pilot studies and subsequent systematic validation across different territorial contexts. Although the tool has not yet undergone inter-rater reliability testing or field validation, it has been designed to be usable by professionals with diverse backgrounds—including public veterinarians, clinical psychologists, and social workers—thanks to a shared coding system and complementary sections.
To support its practical application, a simulated case is included in the Supplementary Materials, illustrating the implementation of the protocol in a realistic scenario. The overarching aim is for this model to contribute to the development of regional observatories and inter-institutional networks for the coordinated prevention and management of animal hoarding cases, including in the context of international cooperation.

8. Implications for Implementation and Operational Training

The full effectiveness of the proposed protocol depends on its proper application by qualified and adequately trained professionals. For this reason, the activation of well-defined training programs is strongly recommended, aimed at providing the minimum competencies required for the conscious and interprofessional use of the proposed tools.
The recommended training pathway includes three main components. The first focuses on the clinical and regulatory framework of animal hoarding, offering a four-hour overview of diagnostic criteria, veterinary and social implications, and relevant legislation. The second involves a four-hour guided session dedicated to the completion of the protocol, providing practical instructions for using the Preliminary Observational Form, the Clinical-Relational Interview, and the Veterinary Health Record. The third component consists of case simulations and joint exercises, lasting approximately four hours, in which participants apply the protocol to real or simulated scenarios, engage in multidisciplinary discussion of the evaluations, and reflect on potential assessment biases.
A total duration of at least 12 h is recommended. These sessions may be organized either online or in person, and should involve professionals from various disciplines, including veterinarians, psychologists, social workers, and public health authorities, to promote a shared and coordinated approach.

9. Conclusions

Animal hoarding constitutes a complex and multifaceted phenomenon that demands operational responses grounded in a multidimensional understanding—integrating clinical, relational, environmental, and legal dimensions. Findings from the retrospective analysis confirm the urgent need for innovative tools to support effective, coordinated, and lasting case management.
The proposed protocol represents an initial step toward standardizing interventions through shared, replicable, and adaptable instruments. The three integrated tools—the Preliminary Observational Form (POF), the Clinical-Relational Interview for Animal Hoarding (ICRAH), and the Veterinary Health Record (VHR)—form a structured operational framework enabling systematic data collection, tailored intervention planning, and longitudinal monitoring of each case.
Field experience highlights that only a stable, interdisciplinary, and well-coordinated approach—bringing together public veterinarians, psychiatrists, psychotherapists, social workers, health authorities, and law enforcement—can ensure effective outcomes. Within this framework, the public veterinarian plays a pivotal role, not only in the clinical evaluation of animals but also as a mediator among institutional stakeholders.
Given the clinical complexity, the high risk of relapse, and the significant public health implications, the establishment of dedicated services and regional observatories is both urgent and strategic. These structures should guarantee continuity of care, professional specialization, and systematic data integration across sectors.
In this light, animal hoarding emerges as a crucial test case for the real-world application of the One Welfare approach [42], which recognizes the systemic interdependence of animal welfare, human mental health, and environmental conditions. Intervening in such cases is not merely a matter of health protection or legal enforcement, but an opportunity to activate relational ecosystems of care—where the well-being of individuals, animals, and communities are addressed as inseparable dimensions of shared vulnerability. The protocol presented here offers a concrete, scalable tool for translating this vision into operational practice, promoting not only the containment of critical situations but a cultural shift in the management of complex vulnerabilities, and providing a conceptual foundation for future validation and adaptation in different national and international contexts.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/ani15213222/s1: File S1. Preliminary Observational Form (POF); File S2. Structured Clinical-Relational Interview for Animal Hoarding (ICRAH); File S3. Veterinary Health Record for Animals in Hoarding Contexts (VHR-AH); File S4. Simulated case—POF (completed example); File S5. Simulated case—ICRAH (completed example); File S6. Simulated case—VHR (completed example).

Author Contributions

Conceptualization, A.L., F.B., A.C., G.R. (Gianna Regoli) and G.R. (Giancarlo Ruffo); Methodology, A.L., F.B. and G.R. (Giancarlo Ruffo); Validation, G.R. (Gianna Regoli) and G.R. (Giancarlo Ruffo); Investigation, A.L., F.B. and A.C.; Data Curation, A.L., F.B., G.R. (Gianna Regoli) and A.C.; Writing—Original Draft Preparation, F.B., A.L. and G.R. (Giancarlo Ruffo); Writing—Review and Editing, F.B., A.L., A.C. and G.R. (Giancarlo Ruffo); Supervision, F.B. and G.R. (Giancarlo Ruffo). All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Institutional Review Board Statement

Ethical review and approval were waived for this study because it did not involve the collection of new data from human participants or animals. The study is based on the analysis of anonymized archival documentation regarding previously managed cases and on simulated case materials created solely for illustrative and methodological purposes. No experimental procedures were performed and no personal identifying information was used.

Data Availability Statement

The data presented in this study are not publicly available due to the sensitive nature of the information, which involves both people and animals, but may be provided by the corresponding author upon reasonable request.

Conflicts of Interest

The authors declare no conflicts of interest.

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