Submitted Successfully!
To reward your contribution, here is a gift for you: A free trial for our video production service.
Thank you for your contribution! You can also upload a video entry or images related to this topic.
Version Summary Created by Modification Content Size Created at Operation
1 -- 5360 2022-10-25 16:07:53 |
2 format Meta information modification 5360 2022-10-26 05:49:28 |

Video Upload Options

Do you have a full video?


Are you sure to Delete?
If you have any further questions, please contact Encyclopedia Editorial Office.
Prato-Previde, E.;  Ricci, E.B.;  Colombo, E.S. The Complexity of the Human–Animal Bond. Encyclopedia. Available online: (accessed on 15 June 2024).
Prato-Previde E,  Ricci EB,  Colombo ES. The Complexity of the Human–Animal Bond. Encyclopedia. Available at: Accessed June 15, 2024.
Prato-Previde, Emanuela, Elisa Basso Ricci, Elisa Silvia Colombo. "The Complexity of the Human–Animal Bond" Encyclopedia, (accessed June 15, 2024).
Prato-Previde, E.,  Ricci, E.B., & Colombo, E.S. (2022, October 25). The Complexity of the Human–Animal Bond. In Encyclopedia.
Prato-Previde, Emanuela, et al. "The Complexity of the Human–Animal Bond." Encyclopedia. Web. 25 October, 2022.
The Complexity of the Human–Animal Bond

The human–animal relationship is ancient, complex and multifaceted. It may have either positive effects on humans and animals or poor or even negative and detrimental effects on animals or both humans and animals. A large body of literature has investigated the beneficial effects of this relationship in which both human and animals appear to gain physical and psychological benefits from living together in a reciprocated interaction. However, analyzing the literature with a different perspective it clearly emerges that not rarely are human–animal relationships characterized by different forms and levels of discomfort and suffering for animals and, in some cases, also for people. The negative physical and psychological consequences on animals’ well-being may be very nuanced and concealed, but there are situations in which the negative consequences are clear and striking, as in the case of animal violence, abuse or neglect. Empathy, attachment and anthropomorphism are human psychological mechanisms that are considered relevant for positive and healthy relationships with animals, but when dysfunctional or pathological determine physical or psychological suffering, or both, in animals as occurs in animal hoarding.

human–animal relationship human–animal bond empathy attachment anthropomorphism animal-hoarding

1. The Multifaceted Nature of the Human–Animal Relationship

Comparative studies have revealed a wealth of commonalities between humans and nonhuman animals that allows them to engage in interspecific social relationships [1][2][3][4][5][6][7].
As pointed out in [1], one reason why humans are both willing and capable to relate to animals is the presence of basic biological structures and mechanisms that are relevant in social contexts; these mechanisms are shared between humans and other animals and are highly conserved among vertebrates. Basic mechanisms that enable human intraspecific close relationships and bonds appear to also be involved in the relationships and bonds with animals, and various nonhuman species may form intense and durable bonds with people (e.g., [8][9]).
Studies on companion and farm animals show that the way in which animals are considered, treated and cared for is strongly affected by peoples’ characteristics such as personality, attitudes, empathy and attachment levels and beliefs in animals’ mental capacities (e.g., [10][11]). In addition, sociodemographic variables, such as gender, age, family structure, education level and previous experiences with animals, play a role [12][13][14][15][16][17].
Gender differences are well documented in the literature, with women consistently showing higher levels of empathy and concern regarding animal suffering, holding more positive attitudes towards animals and being more engaged in animal protection and less prone to animal exploitation, animal abuse and cruelty [14][16][18][19][20][21]. Apostol et al. [14], for example, reported that gender was a good predictor of attitudes towards animals, together with empathy towards animals, anthropomorphic beliefs and owning a companion animal.
Personality has been associated with positive attitudes to animals, and there is a relationship between psychopathic personality traits and animal abuse and violence [10][22][23]. Empathy and attachment are both related to the quality of human–animal relationships and problems in empathy, attachment and emotion regulation are associated with animal abuse and cruelty [24][25][26][27].
Attitudes, broadly defined as psychological tendencies to evaluate a particular entity (e.g., humans or animals) with some degree of favor or disfavor [28], are important in shaping the human–animal relationship and bond and are reported to play a key role in determining animals’ health and welfare. According to [13], two main aspects underlie human attitudes toward animals: “affect”, which can be defined as people’s affective and emotional responses to animals, and “utility”, i.e., people’s perceptions of animals’ instrumental value. Serpell [13] suggests that the relative strength of these factors would depend on individual characteristics, experience, cultural factors and also on the specific attributes of animals.
The role of experience and culture in human–animal relationships is well documented in the literature: on the one hand the range of animals kept as pets around the world is exceptionally wide [29]; on the other hand, human–companion animal relationship styles vary considerably across cultures [30][31]. In Western countries, for example, dogs and cats are mainly kept for companionship, and the idea of eating them is considered intolerable and morally unacceptable; however, in other countries (e.g., China and Vietnam), these species are both kept as pets and consumed [32][33][34]. Moreover, in many Western countries, cats and dogs are the most popular and beloved companion animals, but, at the same time, a huge number of them (and other pets) are abandoned, neglected, abused and needlessly euthanized every year [35][36][37]. Finally, most people care about pet welfare, but for various reasons, there is still less concern regarding farm animals’ (e.g., pigs, cows and chickens) welfare [38][39].
Regarding animal characteristics, people generally do not see all animals as equal, as their physical and behavioral traits play a role in how they are perceived, considered and treated [13][40][41]. Humans tend to prefer animals that are phylogenetically close to them and perceived as physically, behaviorally or cognitively similar; these aspects trigger more positive affect and attachment and caregiving behaviors, as well as greater empathy and a higher concern in terms of welfare and conservation [42][43][44][45][46][47]. At the same time, in all human societies, animals are ranked on a ‘‘ladder of worth” as is almost everything else, including other humans [48][49].
Knight et al. [41] suggested that the variability in people’s attitudes to the use and exploitation of animals depends on a combination of different factors including beliefs about the mental capacities of animals, perceived superiority of humans, availability of alternatives to the use of animals for various purposes (e.g., medical research and food) and whether the problem of animal exploitation has any direct personal relevance. Belief in the animal mind appears to be a good predictor of attitudes towards animals and their use and abuse for the benefit of humans (e.g., entertainment, experimentation and financial gain [50][51]). The propensity to use animals is greater when people believe there is no alternative, when their knowledge of how animals are used is poor, when the affinity with animals is low and when the perceived benefits of using animals outweigh the costs [41].
Finally, there is evidence that people, when facing situations of conflict regarding animal well-being and suffering, tend to “build arguments” that justify and corroborate their existing attitudes or behavior to avoid dissonance [52]. This has been clearly demonstrated in the “meat paradox”, which shows that those that consume meat may overcome the cognitive dissonance resulting from a positive attitude towards both animals and meat by living either in a state of “tacit denial” regarding animals being killed to produce meat or by denying that animals can suffer [53][54]. In other words, mental abilities and the capacity for suffering tend to be attributed by people to animals when it is in their interest and motivation and not when it does not suit them [55].

2. Human–Animal Relationships: Two Sides of the Story?

Given the array of factors involved in most human–animal relationships, it is not surprising that people relate to animals in very different ways that range from highly positive, affectionate and caring to highly negative, dysfunctional or abusive [30][32][48][49][56][57]. As Ascione and Shapiro [58] pointed out, for every study showing that the human–animal relationship can be beneficial and built on love and caring, another deals with animal exploitation or abuse including the abandonment and neglect of companion animals or cases of dog fighting or animal hoarding. Moreover, attachment, empathy and concern for animals do not necessarily guarantee their welfare, and people may disagree on the proper way to treat animals or on what constitutes a fair human–animal relationship [12].
For example, Mota-Rojas et al. [59] outlined how adverse consequences on pets’ welfare might depend on widespread and apparently affectionate and caring behaviors, such as dressing pets, application of cosmetics, letting them sleep in beds or overfeeding them, emphasizing that people’s behavior towards companion animals should be based on the understanding and respect of their natural needs rather than on supposed similarities and an affective involvement.
Therefore, people’s relationships with animals in general (farm, zoo and wild animals) and with companion animals cannot be easily categorized into positive (i.e., caring and affectionate) and negative (i.e., neglecting or abusive).
A large body of scientific literature has considered the physical and psychological benefits that both humans and animals may obtain by living together in a reciprocated interaction (e.g., humans: 21, [60][61][62][63][64]; see [65][66] for critical analyses; animals: [67][68][69]). However, there is also extensive literature showing that human–animal relationships are characterized by different forms and levels of discomfort and suffering for animals (e.g., [58][59][70][71][72][73]).
As occurs in interpersonal relationships, human beings not only and not always care about the well-being of animals but also pursue their own personal needs, desires and goals; human’s psychological characteristics, self-interest and specific contingent needs and goals may, deliberately or not, prevail in jeopardizing the relationship and the animal’s well-being, leading to dysfunctional or even pathological interactions. Keeping wild species under unnatural conditions for leisure or personal gratification, exploiting farm animals through intensive farming causing them high levels of distress and pain, and abandoning domestic animals mostly for trivial reasons are only a few examples of poor and dysfunctional relationships that are topics of research and debate in the human–animal relationship literature [36][74][75][76].
The type of companionship sought by people may vary to a great degree, and companion animals may be acquired and kept mainly to fulfill different human needs and desires [12][77][78][79][80][81]. Some species, either unusual, rare or expensive, are kept as status symbols [78][82][83]; some breeds may serve as status objects and are appreciated just for their pedigree or appearance [84]. Companion animals, mainly dogs and cats, can serve as child substitutes or as toys [82][85][86].
Tuan [85] suggested that when pets are used as toys, they are treated capriciously to gain a sense of power and control that is also expressed through training them to obey to commands. Companion animals, especially dogs, can also serve as extensions of their owners’ self: they may extend their owners’ self not only symbolically by helping them to be something desired but also literally by providing them opportunities to do things that they could not otherwise do such as to engage in childlike games and playful activities or to extend their sphere of interpersonal relationships [79][87]. Keeping pets as an extension of the self implies that they are seen as expressions of the individual’s identity and as part of the person, and thus remaining without them is not conceivable; seeing animals as part of the self involves having an emotional attachment towards them and not just a functional one [88][89].
Finally, there are several examples of negative effects of the human–animal relationship, which include cruel acts and violence towards animals, with various characteristics and different degrees of severity (e.g., [56][72][90][91][92]).
Considering the human–animal relationship with all its nuances helps not only to gain a better understanding of the multidimensional and even contradictory nature of the interactions with other species but also to further explore the mechanisms involved in the “hows” and the “whys” of human behavior’’ [12][30][56][93].

3. Animal Hoarding: A Pathological Human–Animal Bond

Animal hoarding is a highly dysfunctional and pathological form of human–animal relationship, which has been defined by Patronek [70] as “the third dimension of animal abuse”, since it entails substantial and protracted animal maltreatment and suffering. Due to the fact of its characteristics, it cannot be easily incorporated into the two well-recognized categories of animal cruelty: deliberate animal abuse and neglect [70]. Indeed, in animal hoarding, animals are exposed to considerable physical and psychological suffering, but often there is a strong human–animal bond, with considerable impairment also of the hoarder’s welfare, who may lack insight regarding the real situation.
Since early reports [94][95], it has clearly emerged that the association between severe animal suffering and a strong attachment to animals was in contradiction with the existing evidence on the human–animal bond [70][96][97]. The evidence that has emerged so far invites scholars to an in-depth reflection on the boundaries between the “normal” and pathological aspects of the human–animal relationship and the mechanisms involved [12][90]. For a long time, hoarding animals was considered a “lifestyle” typical of bizarre and strange animal lovers, mainly women, but now it is considered a form of animal abuse, and in recent years, it has been recognized as a mental disorder acknowledged in the DSM-5 as a form of hoarding disorder (i.e., animal hoarding disorder (AHD) [98], although with its own characteristics and peculiarities.
Hoarding disorder (HD), or compulsive hoarding, is characterized at the behavioral level by problematic behaviors of accumulation, a persistent and considerable difficulty in discarding ordinary items, squalor, personal neglect and poor insight into such disruptive behavior. Hoarding behavior prevents the ordinary use of living spaces in the home, causing significant distress and impairing everyday functioning [98][99][100]. HD has been associated to various factors such as interpersonal conflicts, health issues [101], anxiety-based disorders, depression, family and social disabilities, progressive functional deficit [102], social isolation and difficulties in bonding with other people [103]. In addition, an association with cognitive deficits in attention, memory and executive functions (e.g., planning, decision-making and inhibitory control) has been reported [104][105][106]. Finally, compulsive hoarding is characterized by a problematic emotional attachment to possessions [99][107][108]. According to a psychological cognitive model, this emotional attachment has three specific aspects: possessions provide comfort and security, possessions have human-like qualities and possessions represent an extension of self-concept [107][109].
Animal hoarding (AHD), in its great complexity, appears to have common characteristics with object hoarding including possible underlying cognitive impairments [106], anxiety, depression, social isolation and relational difficulties [110][111]. However, there is a growing consensus that animal hoarding differs in several respects from object hoarding, the most striking being probably that animal hoarders accumulate living, sentient beings that, differently from objects, need interaction and attention and require continuous nurturing and care. Animal hoarding appears to entail distortions and dysfunctions in attachment, empathy and anthropomorphism and shows how characteristics and motivations that, in general, foster and maintain long-lasting positive relationships with animals may jeopardize the human–animal relationship, causing suffering for both animals and humans [90][112][113].
Animal hoarding occurs when an individual persistently accumulates an unusually large number of animals and fails to provide them with the minimum standards of nutrition, hygiene and veterinary care, exposing them to psychological and physical suffering due to the fact of a seriously distorted relationship with them [90][114].
Hoarders often fail to recognize and act on the deteriorated conditions of the animals (e.g., disease, starvation and death), the severe overcrowding, the lack of hygiene of the home environment, and they are often unaware of the negative effects that the hoarding of animals has their own well-being and on that of others living close to them [94][115][116][117]. Squalid living conditions are common including extreme soiling, parasites, litter, precarious waste, accumulation of feces and urine, nonfunctioning bathrooms and other living spaces, and even dead animals left where they died or are stored [70][118]. Thus, animal hoarding is a multifaceted problem that includes animal maltreatment and abuse, problems related to the health and mental health of hoarders, safety and social and occupational functioning [94][95].
It is worth noting that what defines the disorder is not just the number of animals but the inability of the owner to provide the minimum necessary care for them, to recognize their suffering and to provide them with appropriate sanitary conditions [94][113][119][120][121]. Animal hoarders’ difficulty in relinquishing animals to people who can more adequately care for them is another key point: despite highly negative conditions they form excessive attachments to their animals, consider them like children [122] and feel the urge to save and care for them, even if this results in significant impairment. They also exhibit intense distress when the animals are removed from their care [107][113][118].
Despite its complexity and the highly negative impact on both animals and people, animal hoarding has long been underestimated both within and outside the academic community; however, recently, interest has grown in different research areas such as mental health, psychiatric disorders, human–animal relationships and veterinary practice [90][115][123][124][125].
Animal hoarding is not limited to a specific culture or country, and in addition to the US, it has been reported in various countries, including the UK [126], Canada [121][127], Australia [117][128], Serbia [129], Spain [116], Italy [124], and Brazil [119][130], and can represent a significant problem [106][115][131]. For example, [131] evaluated the situation of animal hoarding in Germany, reporting 120 animal hoarding cases between 2012 and 2015 for a total of 9174 hoarded animals, mainly cats, dogs and small mammals. The highest number of accumulated animals was documented in [124] in Italy, with a total of 450 hoarded animals.
Some research of the literature provide a portrait of the main characteristics of animal hoarders and the factors that may be involved in the emergence of the disorder [90][125][132]. Overall, the studies outline that animal hoarding is a chronic disorder that progressively deteriorates [116][117]. As regards an animal hoarder’s characteristics, the literature shows that the disorder is more frequent among women, who constitute, on average, between 70% and 83% of animal hoarders [90][125][132]. This rate has been confirmed in most of the reported hoarding cases (e.g., [106][116][128][133]). Although the reasons for this gender effect have not yet been ascertained, it could be related to the greater predisposition of women to empathize with animals and to be attracted by the infantile characteristics typical of most pets, especially dogs and cats, which are in fact the species most involved in hoarding situations. Gender differences in attitudes, empathy and attachment and concern towards animals have also been well documented in the literature on the “bright side” of the human–animal bond [14][16].
Individuals showing animal hoarding are reported to be socially isolated, in their fifties or sixties, on average, when identified [106][116][117][119][128] and in approximately 70% of the cases are single, divorced or widowed [106][119]. Studies also show that hoarders are often unemployed or retired but may also be breeders who initially bred animals for economic reasons [117][119][128][133][134]. However, the phenomenon emerges in all demographic socioeconomic conditions [90][125][132]; even individuals who are well integrated into society may be affected (e.g., health care workers, public employees, lawyers and veterinarians), and not uncommonly hoarders live with people who depend on them, including children, people with disabilities or elderly people, who may find themselves sharing the same living conditions as the animals being accumulated.
Three main types of animal hoarders have been described in the literature, who show different characteristics and different levels of severity [94][135]. These characteristics regard the presence of medical/psychological problems, involvement in society, awareness of the problem, attitude towards authority and risks for animals but also attachment to animals, empathy towards them and the tendency to anthropomorphize them [90][113].
The “overwhelmed caregivers” [94][135] are usually lonely people with a strong attachment to and empathy for animals, who initially provide proper care to them but eventually become overwhelmed due to the fact of difficulties such as illness, economic problems or a bereavement. Their self-esteem is linked to the role of caregiver, and they often adopt animals in a passive way (people give them animals knowing they love them). These hoarders may have mood disorders but show a certain level of awareness of their problems, respect authority and are cooperative.
For “rescue hoarders” [94][135], saving animals is a mission and they are convinced they are the only ones who can provide adequate care to them. These hoarders have a need to acquire animals actively, adopting them from shelters or through flyers or social networks. After rescuing animals, these hoarders prevent their adoption, are afraid they could die and are opposed to euthanasia even when seeing them suffering and healing them is impossible. Thus, the number of animals gradually overwhelms their capacity to provide the minimal care. They are not necessarily isolated but may have a network of helpers that provide them animals to care for. Indeed, these hoarders may be found among people working in rescue shelters or in veterinary clinics, who believe they can save all animals by taking them home [134]. These types of hoarders avoids authorities and/or impedes their access, making the solution to the problem difficult.
The last type reported in the literature is the “exploiter hoarders” [94][135], who acquires animals to serve their own needs (e.g., absolute control and demonstration of expertise). They lack empathy for people/animals, are indifferent to the harm caused to animals or people and are frequently manipulative and devise strategies to avoid controls. They tend to deny the problem and reject concerns from any authorities over the animals’ care. However, it has been outlined that exploitative hoarding is often associated with sociopathic traits or personality disorders, either narcissistic or antisocial, that resemble much more those of people who engage in criminal behavior and animal abuse and cruelty.
Overall, the literature indicates that a hoarder’s story begins with relatively few animals, and that gradually, the situation deteriorates through the continual acquisition of animals (actively or passively) despite a lack of money and time for them, avoidance of sterilization, insufficient veterinary care and the struggle to keep the house sufficiently clean. The incipient hoarder and the breeder–hoarder are considered intermediate stages that may evolve over time into full-blown hoarding [135][136]. Different from an incipient hoarder, a breeder initially keeps animals for shows or to sell but over time finds it increasingly difficult to care for them properly. They do not always keep the animals in their own home; thus, their living conditions may not always be as neglected as those of the animals. However, this is not the rule, since many hoarders set-up home breeding. They usually have only a moderate awareness of the state of the animals and their ability to care for them; thus, they continue to raise them.

Empathy, Attachment and Anthropomorphism in Animal Hoarding

In general, animal hoarders show a highly dysfunctional relationship with animals, characterized by distorted overattachment to them, empathy disfunction and a high level of anthropomorphism [90][113][132]. Their behavior, especially that of incipient hoarders, overwhelmed caregivers and rescue hoarders, is most often rooted in a real desire to take care of animals or save them and is characterized by a strong emotional attachment to animals and an extreme distress, often genuine despair, at the idea of being separated from them. Patronek and Nathanson [137] reported that when attempting to account for their behavior, these hoarders often mention their love for animals. However, the situation degenerates from helping into a form of abuse such that, even though the intent is not to harm animals, severe and prolonged suffering is caused to them [118].
In most hoarding situations, the emotional attachment to animals, which is a basic aspect of the human–animal relationship, is distorted, formed with many individuals and immediately triggered to the point that any animal encountered can be easily seen as one’s own and the individual feels obliged to take care of it [138].
It could be hypothesized that empathy (in particular affective empathy) could be the initial mechanism that makes these people sensitive to the needs and suffering of animals, motivating them to take care of them; however, when facing the evidence of their inability to care for animals properly, a denial process would take place to protect their sense of identity and self-esteem, both strongly rooted in the link with animals, in the belief of a special connection with them and in the presumed ability to take care of them. Furthermore, empathy could decrease as a result of exposure to suffering due to the fact of habituation and/or to avoid an excessive level of personal distress or even to dealing with many individuals and a reduction in personal contact [139][140]. Conversely, “exploiter hoarders” generally lack empathy for animals and people, being more similar to people with an antisocial personality and who exhibit such behavior and are prone to animal abuse, in whom empathy towards animals and people is compromised in some way [141][142].
Hoarders also tend to anthropomorphize animals to a greater extent compared to ordinary animal owners. Steketee et al. [113] observed that 81% of animal hoarders (compared to 27% of owners) tended to ascribe to them the same characteristics and intelligence of humans and to view them as their “children”. In fact, they often report a strong attachment to their animals and consider them to be like children [122]. This often results in a distorted sense of responsibility and a strong need for control over the animals, whereby the hoarders feel that they must acquire animals and should not separate from them to ensure that nothing bad happens to them.
In “rescuer hoarders”, these aspects would be strongly linked to the problem of death: they appear to consider the deterioration of their living conditions as a necessary sacrifice to help creatures in need, who might otherwise die [138], and some of them explicitly state that they would like to create shelters that do not include euthanasia [143]. Thus, there is a real urge to rescue animals, which is experienced as a duty, leads to a strong sense of guilt if disregarded and is linked to the constant concern that something terrible could occur to the animals if they were not helped (e.g., being hit by a car or ending up in a vivisection laboratory) [138]. Since animals, as all living beings do, die and separation from them is inevitable, anxiety relative to control and responsibility is further enhanced in hoarders [137]. These individuals may have intense emotional reactions of anger or distress triggered by thoughts of loss or separation [105] and often are unable to separate themselves from the bodies of dead animals, keeping them inside the house [94][95][118]. Based on these extreme reactions of separation-related distress and anger, Reference [144] hypothesized that the propensity of animal hoarders to ignore the problems arising from acquiring an increasing number of animals and to convince themselves that the animals are well might be a way to avoid the unpleasant feelings that would result from giving animals up for adoption or from acknowledging the severely poor conditions of their animals.
Emotional attachment, concern for animals and empathy are less explanatory in the case of “exploiter hoarders”, whose motivations for hoarding could be linked to a need to dominate and control or to financial interest (especially in the case of anti-social personalities) or to the desire to establish relationships that confirm their value, in which other individuals (in this case animals) have the role of self-objects, serving to ensure attentions and adoration (in narcissists; [135]). Similar motivations, however, can be observed in a far more nuanced form also in so called “normal” non abusive human–animal relationships [12][79][85][145].
For animal hoarders, animals also have an instrumental role, which is functional to the preservation of their sense of identity and self-esteem, associated with the role of caregiver and is constantly reinforced by the perception of having positive relationships with living beings that are sentient and totally dependent [137][138]. Self-esteem would derive partly from the sense of self-efficacy—through the control over the animals (especially in the exploiter) and in part by seeing recognized their ability as caregivers through the affection received by the animals, [137][146]. However, the primary source of self-esteem is the interaction within the human–animal relationship: animals are highly focused on the person and do not judge or criticize, and they cannot object to misinterpretations of their feelings and needs [137].
The central role of animals in fostering and maintaining an individual’s self-esteem and sense of identity has also been documented in studies on normal human–animal relationships and are one of the psychologically positive effects of the human–animal bond [61][147][148].
Like non-hoarders, incipient hoarders, overwhelmed caregivers and rescue hoarders derive a sense of security and comfort due to the fact of animals’ capacity to provide emotional support and unconditional love in a relationship that is perceived as less dangerous than those with other people [118][134]. Animal hoarders are reported to have difficulties in establishing affective bonds with others, tend to maintain social isolation [111][113] and prefer contact with animals [118][134]. They could consider their relationships with animals as safer and more rewarding than interactions with humans [118][137]. Cats and dogs are the most accumulated species [121][132] but also the two most common species of companion animals; they have a long history of domestication and close association with humans, live close to them and are widely considered as important social partners by their owners in many countries. However, hoarded animals may include a variety of animals, such as miniature ponies, deer, ferrets, pigs, various species of birds, and even spitting llamas, and multiple species may be present in any isolated hoarding case [121].
Steketee et al. [113] interviewed individuals who fit the criteria for animal hoarding and individuals owning many animals but not meeting the hoarding criteria, reporting that both hoarders and non-hoarders had stressful life events in childhood and adulthood, strong feelings about animals such as the desire to rescue, take care of and be close to them. Animal hoarders, however, had more dysfunctional interpersonal relationships and mental health concerns and anthropomorphized animals more often; however, the most significant difference between the two samples was the presence of a chaotic domestic environment during childhood and childhood problems with caregivers (e.g., unstable, neglectful, abusive, absent, and/or inconsistent parents). In another study [93], it was analyzed whether people owning 20 or more cats shared the commonly reported psychological and demographic profile of animal hoarders compared to owners of 1–2 cats drawn from the same population. They found that people who owned many cats were more similar to clinical animal hoarders in age and pet attachment levels than the typical cat owners, but they differed in functioning, veterinary care and home organization.
The quality of caregiving and attachment during infancy seem to play an important role in the emergence of animal hoarding, and animal hoarders often report that during childhood they relied on companion animals, suggesting that in difficult developmental situations companion animals may function as alternative attachment figures providing intimacy and security without fear of rejection [149]. Nathanson and Patronek [150] hypothesized that when parenting was neglectful, inconsistent or abusive, animals became crucial in animal hoarders’ childhood to maintain and promote empathy, comfort, calm, acceptance and self-esteem, as previously suggested by Brown [88][89][151] in the theory of animals as self-object. Secure attachment in early childhood is considered essential for normal emotional development, emotion regulation, empathy and good interpersonal relationships [149][152] and attachment to pets plays an important role in normal social, emotional and cognitive development, promoting mental health, well-being and quality of life [1][5].
Due to the occurrence of developmental and life events, animal hoarders may develop in adulthood a compensatory over-reliance and an overattachment to animals, with animals becoming a dysfunctional solution to cope with their need for relationships and intimacy without fear of rejection and abandonment [137]. An abusive, traumatic or dysfunctional childhood is correlated with a disorganized attachment style, which can result in compulsive caregiving. This caregiving style, differently from the sensitive caregiving style (i.e., the ability to be responsive and attuned with another’s individual support-seeking behavior), is characterized by the tendency to provide care obsessively and intrusively, irrespective of whether the care is wanted or needed [153][154][155]. In adulthood the compulsive caregiving of animals can become the primary way to maintain or building a sense of self. This kind of controlling behavior often characterizes the caregiving style of animal hoarders, together with other forms of control typical of animal hoarders including refusal to adopt, rejection of help and expert opinions regarding proper animal care and sometimes the saving of dead bodies [137].
Probably, one of the most perplexing aspects of animal hoarding is that animal hoarders declare to love animals and want to care for them but, in fact, their animals are terribly neglected and suffering. This lack of insight is typical of animal hoarders, and it has been suggested that being unaware of the degradation in their personal lives and those of their animals could be suggestive of dissociation [137].
Dissociation represents a self-protective strategy to avoid negative feelings associated with distress or trauma [156] and can make it difficult to understand and respond to others’ feelings as well as easier to view them as less than human [149]. In the case of animal hoarders, dissociation would represent a strategy to preserve the integrity of the self, the self-image and the mission of caregivers, notwithstanding the extremely precarious conditions of their animals.
It has been argued that dissociation may be best understood as a continuum from more common, normal manifestations to less common and more pathological symptoms [157]. Indeed, in [158] it was reported that in a sample of college students, dissociation was positively associated with attachment to companion animals, and this result was then replicated in another student sample [159].


  1. Julius, H.; Beetz, A.; Kotrschal, K.; Turner, D.; Uvnäs-Moberg, K. Attachment to Pets: An Integrative View of Human-Animal Relationships with Implications for Therapeutic Practice; Hogrefe Publishing: Göttingen, Germany, 2012.
  2. Dunbar, R.I.; Shultz, S. Bondedness and sociality. Behaviour 2010, 147, 775–803.
  3. Massen, J.J.M.; Sterck, E.H.M.; de Vos, H. Close social associations in animals and humans: Functions and mechanisms of friendship. Behaviour 2010, 147, 1379–1412.
  4. Odendaal, J.S.; Meintjes, R.A. Neurophysiological correlates of affiliative behaviour between humans and dogs. J. Vet. Behav. 2003, 165, 296–301.
  5. Beetz, A.; Uvnäs-Moberg, K.; Julius, H.; Kotrschal, K. Psychosocial and psychophysiological effects of human-animal interactions: The possible role of oxytocin. Front. Psychol. 2012, 3, 234.
  6. Nagasawa, M.; Mitsui, S.; En, S.; Ohtani, N.; Ohta, M.; Sakuma, Y.; Kikusui, T. Oxytocin-gaze positive loop and the coevolution of human-dog bonds. Science 2015, 348, 333–336.
  7. Carter, C.S.; Porges, S.W. Neural mechanisms underlying human-animal interaction: An evolutionary perspective. In The Social Neuroscience of Human-Animal Interaction; Freund, L.S., McCune, S., Esposito, L., Gee, N.R., McCardle, P., Eds.; American Psychological Association: Washington, DC, USA, 2016; pp. 89–105.
  8. Prato-Previde, E.; Valsecchi, P. The immaterial cord: The dog human attachment bond. In The Social Dog: Cognition and Behavior; Kaminski, J., Marshall-Pescini, S., Eds.; Elsevier: Berkeley, CA, USA, 2014; pp. 165–185.
  9. Rockett, B.; Carr, S. Animals and attachment theory. Soc. Anim. 2014, 22, 415–433.
  10. Furnham, A.; McManus, C.; Scott, D. Personality, empathy and attitudes to animal welfare. Anthrozoös 2003, 16, 135–146.
  11. Ellingsen, K.; Zanella, A.J.; Bjerkås, E.; Indrebø, A. The relationship between empathy, perception of pain and attitudes toward pets among Norwegian dog owners. Anthrozoos 2010, 23, 231–243.
  12. Blouin, D.D. Understanding relations between people and their pets. Sociol. Compass 2012, 6, 856–869.
  13. Serpell, J.A. Factors influencing human attitudes to animals and their welfare. Anim. Welf. 2004, 13 (Suppl. S1), 145–151.
  14. Apostol, L.; Rebega, O.; Miclea, M. Psychological and Socio-demographic Predictors of Attitudes toward Animals. Procedia Soc. 2013, 78, 521–525.
  15. Daly, B.; Morton, L.L. Empathic differences in adults as a function of childhood and adult pet ownership and pet type. Anthrozoös 2009, 22, 371–382.
  16. Herzog, H.A. Gender differences in human-animal interactions: A review. Anthrozoos 2007, 20, 7–21.
  17. Leon, A.F.; Sanchez, J.A.; Romero, M.H. Association between attitude and empathy with the quality of human-livestock interactions. Animals 2020, 10, 1304.
  18. Signal, T.D.; Taylor, N. Attitudes to Animals: Demographics within a Community Sample. Soc. Anim. 2006, 12, 147–157.
  19. Signal, T.D.; Taylor, N. Attitude to animals and empathy: Comparing animal protection and general community samples. Anthrozoös 2007, 20, 125–130.
  20. Colombo, E.; Pelosi, A.; Prato-Previde, E. Empathy towards animals and belief in animal-human-continuity in Italian veterinary students. Anim. Welf. 2016, 25, 275–286.
  21. Colombo, E.S.; Crippa, F.; Calderari, T.; Prato-Previde, E. Empathy toward animals and people: The role of gender and length of service in a sample of Italian veterinarians. J. Vet. Behav. 2017, 17, 32–37.
  22. Mathews, S.; Herzog, H. Personality and attitudes towards the treatment of animals. Soc. Anim. 1997, 5, 57–63.
  23. Erlanger, A.C.E.; Tsytsarev, S.V. The relationship between empathy and personality in undergraduate students’ attitudes toward nonhuman animals. Soc. Anim. 2012, 20, 21–38.
  24. Gullone, E. The Development of Antisocial Behaviour. In Animal Cruelty, Antisocial Behaviour, and Aggression; Palgrave Macmillan: London, UK, 2012; pp. 25–38.
  25. Gullone, E. Risk factors for the development of animal cruelty. J. Anim. Ethics 2014, 4, 61–79.
  26. Thompson, K.L.; Gullone, E. Prosocial and antisocial behaviors in adolescents: An investigation into associations with attachment and empathy. Anthrozoös 2008, 21, 123–137.
  27. Hartman, C.; Hageman, T.; Williams, J.H.; Mary, J.S.; Ascione, F.R. Exploring empathy and callous–unemotional traits as predictors of animal abuse perpetrated by children exposed to intimate partner violence. J. Interpers. Violence 2019, 34, 2419–2437.
  28. Eagly, A.H.; Chaiken, S. Psychology of Attitudes; Harcourt, Brace Jovanovich: New York, NU, USA, 1993.
  29. Serpell, J.A. Pet-keeping in non-western societies: Some popular misconceptions. Anthrozoös 1987, 1, 166–174.
  30. Herzog, H. Some We Love, Some We Hate, Some We Eat: Why It’s So Hard to Think Straight about Animals; HarperCollins: New York, NY, USA, 2010.
  31. Herzog, H. Biology, culture, and the origins of pet-keeping. Anim. Cogn. 2014, 1, 296–308.
  32. Podberscek, A.L. Good to pet and eat: The keeping and consuming of dogs and cats in South Korea. J. Curr. Soc. Issues 2009, 65, 615–632.
  33. Podberscek, A.L. An Appetite for Dogs: Consuming and Loving Them in Vietnam. In Companion Animals in Everyday Life; Palgrave Macmillan: New York, NY, USA, 2016; pp. 111–127.
  34. Bartlett, K.; Clifton, M. How many dogs and cats are eaten in Asia. Anim. People 2003, 12, 18–19.
  35. Bartlett, P.C.; Bartlett, A.; Walshaw, S.; Halstead, S. Rates of euthanasia and adoption for dogs and cats in Michigan animal shelters. J. Appl. Anim. Welf. Sci. 2005, 8, 97–104.
  36. Fatjó, J.; Bowen, J.; García, E.; Calvo, P.; Rueda, S.; Amblás, S.; Lalanza, J.F. Epidemiology of dog and cat abandonment in Spain (2008–2013). Animals 2015, 5, 426–441.
  37. Sharkin, B.S.; Ruff, L.A. Broken bonds: Understanding the experience of pet relinquishment. In The Psychology of the Human-Animal Bond; Blazina, C., Shen-Miller, D., Eds.; Springer: New York, NY, USA, 2011; pp. 275–287.
  38. Tawse, J. Consumer attitudes towards farm animals and their welfare: A pig production case study. Biosci. Horiz. 2010, 3, 156–165.
  39. Tomasevic, I.; Bahelka, I.; Čítek, J.; Čandek-Potokar, M.; Djekić, I.; Getya, A.; Font-i-Furnols, M. Attitudes and beliefs of eastern european consumers towards animal welfare. Animals 2020, 10, 1220.
  40. Borgi, M.; Cirulli, F. Pet Face: Mechanisms Underlying Human-Animal Relationships. Front. Psychol. 2016, 7, 298.
  41. Knight, S.; Vrij, A.; Bard, K.; Brandon, D. Science versus animal welfare? Understanding attitudes toward animal use. J. Curr. Soc. Issues 2009, 65, 463–464.
  42. Plous, S. Psychological mechanisms in the human use of animals. J. Curr. Soc. Issues 1993, 49, 11–52.
  43. Stokes, D.L. Things we like: Human preferences among similar organisms and implications for conservation. Hum. Ecol. 2006, 35, 361–369.
  44. Knight, A.J. “Bats, snakes and spiders, oh my!” How aesthetic and negativistic attitudes, and other concepts predict support for species protection. J. Environ. Psychol. 2008, 28, 94–103.
  45. Batt, S. Human attitudes towards animals in relation to species similarity to humans: A multivariate approach. Biosci. Horiz. 2009, 2, 180–190.
  46. Archer, J.; Monton, S. Preferences for infant facial features in pet dogs and cats. Ethology 2011, 117, 217–226.
  47. Miralles, A.; Raymond, M.; Lecointre, G. Empathy and compassion toward other species decrease with evolutionary divergence time. Sci. Rep. 2019, 9, 19555.
  48. Arluke, A.; Sanders, C.; Sanders, C.R. Regarding Animals; Temple University Press: Philadelphia, PA, USA, 1996.
  49. Arluke, A.; Sanders, C. Between the Species: Readings in Human-Animal Relations; Allyn & Bacon: Boston, MA, USA, 2009.
  50. Hills, A.M. Empathy and belief in the mental experience of animals. Anthrozoös 1995, 8, 132–142.
  51. Knight, S.E.; Vrij, A.; Cherryman, J.; Nunkoosing, K. Attitudes towards animal use and belief in animal mind. Anthrozoös 2004, 17, 43–62.
  52. Knight, S.; Nunkoosing, K.; Vrij, A.; Cherryman, J. Using Grounded Theory to examine people’s attitudes toward how animals are used. Soc. Anim. 2003, 11, 307–327.
  53. Loughnan, S.; Haslam, N.; Murnane, T.; Vaes, J.; Reynolds, C.; Suitner, C. Objectification leads to depersonalization: The denial of mind and moral concern to objectified others. Eur. J. Soc. Psychol. 2010, 40, 709–717.
  54. Bastian, B.; Loughnan, S.; Haslam, N.; Radke, H.R. Don’t mind meat? The denial of mind to animals used for human consumption. Personal. Soc. Psychol. Bull. 2012, 38, 247–256.
  55. Epley, N.; Waytz, A.; Akalis, S.; Cacioppo, J.T. When we need a human: Motivational determinants of anthropomorphism. Soc. Cogn. 2008, 26, 143–155.
  56. Arluke, A. Just a Dog: Understanding Animal Cruelty and Ourselves; Temple University Press: Philadelphia, PA, USA, 2006.
  57. Arluke, A. Our animals ourselves. Contexts 2010, 9, 34–39.
  58. Ascione, F.R.; Shapiro, K. People and animals, kindness and cruelty: Research directions and policy implications. J. Curr. Soc. Issues 2009, 65, 569–587.
  59. Mota-Rojas, D.; Mariti, C.; Zdeinert, A.; Riggio, G.; Mora-Medina, P.; del Mar Reyes, A.; Hernández-Ávalos, I. Anthropomorphism and Its Adverse Effects on the Distress and Welfare of Companion Animals. Animals 2021, 11, 3263.
  60. Serpell, J.A.; Paul, E.S. Pets and the development of positive attitudes to animals. In Animals and Human Society: Changing Perspectives; Manning, A., Serpell, J.A., Eds.; Routledge: London, UK; New York, NY, USA, 1994; pp. 127–144.
  61. McConnell, A.R.; Brown, C.M.; Shoda, T.M.; Stayton, L.E.; Martin, C.E. Friends with benefits: On the positive consequences of pet ownership. J. Personal. Soc. Psychol. 2011, 101, 1239.
  62. McCardle, P.E.; McCune, S.E.; Griffin, J.A.; Maholmes, V.E. How Animals Affect Us: Examining the Influences of Human–Animal Interaction on Child Development and Human Health; American Psychological Association: Washington, DC, USA, 2011.
  63. Wells, D.L. Domestic dogs and human health: An overview. Br. J. Health Psychol. 2007, 12, 145–156.
  64. Wells, D.L. The state of research on human–animal relations: Implications for human health. Anthrozoös 2019, 32, 169–181.
  65. Herzog, H. The impact of pets on human health and psychological well-being: Fact, fiction, or hypothesis? Curr. Dir. Psychol. Sci. 2011, 20, 236–239.
  66. Islam, A.; Towell, T. Cat and dog companionship and well-being: A systematic review. Int. J. Appl. Psychol. 2013, 3, 149–155.
  67. Archer, J. Why do people love their pets? Evol. Hum. Behav. 1997, 18, 237–259.
  68. Mellor, D.J. Enhancing animal welfare by creating opportunities for positive affective engagement. N. Z. Vet. J. 2015, 63, 3–8.
  69. Horowitz, A.; Hecht, J. Examining dog–human play: The characteristics, affect, and vocalizations of a unique interspecific interaction. Anim. Cogn. 2016, 19, 779–788.
  70. Patronek, G. Animal hoarding: A third dimension of animal abuse. International Handbook of Theory and Research on Animal Abuse and Cruelty; Ascione, F.R., Ed.; Purdue University Press: West Lafayette, IN, USA, 2008; pp. 221–246.
  71. Sanders, C.R. Actions speak louder than words: Close relationships between humans and nonhuman animals. Symb. Interact. 2003, 26, 405–426.
  72. Ascione, F.R.; Arkow, P. Child Abuse, Domestic Violence, and Animal Abuse: Linking the Circles of Compassion for Prevention and Intervention; Purdue University Press: West Lafayette, IN, USA, 1999.
  73. Newberry, M. Pets in danger: Exploring the link between domestic violence and animal abuse. Aggress. Violent Behav. 2017, 34, 273–281.
  74. Vollum, S.; Longmire, D.; Buffington-Vollum, J. Moral disengagement and attitudes about violence toward animals. Soc. Anim. 2004, 12, 209–235.
  75. Navarro, J.; Schneider, J.L. Animal cruelty for profit. In Animal Cruelty: A Multidisciplinary Approach to Understanding; Brewster, M.P., Reyes, C.L., Eds.; Carolina Academic Press: Durham, NC, USA, 2013; pp. 127–155.
  76. Grant, R.A.; Montrose, V.T.; Wills, A.P. ExNOTic: Should we be keeping exotic pets? Animals 2017, 7, 47.
  77. Endenburg, N.; Bouw, J. Motives for acquiring companion animals. J. Econ. Psychol. 1994, 15, 191–206.
  78. Hirschman, E.C. Consumers and their animal companions. J. Consum. Res. 1994, 20, 616–632.
  79. Belk, R.W. Metaphoric relationships with pets. Soc. Anim. 1996, 4, 121–145.
  80. Hill, R.P.; Gaines, J.; Wilson, R.M. Consumer behavior, extended-self, and sacred consumption: An alternative perspective from our animal companions. J. Bus. Res. 2008, 61, 553–562.
  81. Benz-Schwarzburg, J.; Monsó, S.; Huber, L. How dogs perceive humans and how humans should treat their pet dogs: Linking cognition with ethics. Front. Psychol. 2020, 11, 584037.
  82. Beverland, M.B.; Farrelly, F.; Lim, E.A.C. Exploring the dark side of pet ownership: Status-and control-based pet consumption. J. Bus. Res. 2008, 61, 490–496.
  83. Seaboch, M.S.; Cahoon, S.N. Pet primates for sale in the United States. PLoS ONE 2021, 16, e0256552.
  84. Packer, R.M.; O’Neill, D.G.; Fletcher, F.; Farnworth, M.J. Great expectations, inconvenient truths, and the paradoxes of the dog-owner relationship for owners of brachycephalic dogs. PLoS ONE 2019, 14, e0219918.
  85. Tuan, Y.F. Dominance & Affection: The Making of Pets; Yale University Press: New Haven, CT, USA, 1984; No. 04; BF632. 5, T8.
  86. Sanders, C.R. The animal ‘Other’: Self definition, social identity and companion animals. Adv. Consum. Res. 1990, 17, 662–668.
  87. Belk, R.W. Possessions and the extended self. J. Consum. Res. 1988, 15, 139–168.
  88. Brown, S.E. The human-animal bond and self psychology: Toward a new understanding. Soc. Anim. 2004, 12, 67–86.
  89. Brown, S.E. Companion animals as self-objects. Anthrozoos 2007, 20, 329–343.
  90. Colombo, E.S.; Prato-Previde, E. Animal Hoarding—Accumulo di Animali: Stile di vita, maltrattamento o psicopatologia? Una rassegna critica della letteratura. Ric. Psicol. 2013, 4, 317–360.
  91. Arluke, A.; Patronek, G.; Lockwood, R.; Cardona, A. Animal hoarding. In The Palgrave International Handbook of Animal Abuse Studies; Palgrave Macmillan: London, UK, 2017; pp. 107–129.
  92. Alleyne, E.; Parfitt, C. Adult-perpetrated animal abuse: A systematic literature review. TVA 2019, 20, 344–357.
  93. Ramos, D.; Da Cruz, N.; Ellis, S.; Hernandez, J.A.E.; Reche-Junior, A. Early stage animal hoarders: Are these owners of large numbers of adequately cared for cats? HAIB 2013, 1, 55–69.
  94. Patronek, G.J. Hoarding of animals: An under-recognized public health problem in a difficult-to-study population. Public Health Rep. 1999, 114, 81–87.
  95. Hoarding of Animals Research Consortium (HARC). Health implications of animal hoarding. Health Soc. Work 2002, 27, 125–136.
  96. Vermeulen, H.; Odendaal, J.S. Proposed typology of companion animal abuse. Anthrozoös 1993, 6, 248–257.
  97. Beck, A.M.; Katcher, A.H. Between Pets and People: The Importance of Animal Companionship; Purdue University Press: West Lafayette, IN, USA, 1996.
  98. American Psychiatric Association . DSM 5: Diagnostic and Statistical Manual of Mental Disorders, 5th ed; American Psychiatric Association: Washington, DC, USA, 2013.
  99. Frost, R.O.; Steketee, G. Hoarding: Clinical aspects and treatment strategies. In Obsessive-Compulsive Disorders: Practical Management, 3rd ed.; Jenike, M.A., Baer, L., Minichiello, W.E., Eds.; Mosby: St. Louis, MO, USA, 1998; pp. 533–554.
  100. Irvine, J.D.; Nwachukwu, K. Recognizing Diogenes syndrome: A case report. BMC Res. Notes 2014, 7, 276.
  101. Tolin, D.; Frost, R.; Steketee, G.; Gray, K.D.; Fitch, K.E. The economic and social burden of compulsive hoarding. Psychiatry Res. 2008, 160, 200–211.
  102. Grisham, J.R.; Steketee, G.; Frost, R.O. Interpersonal problems and emotional intelligence in compulsive hoarding. Depress. Anxiety 2008, 25, E63–E71.
  103. Grisham, J.R.; Martyn, C.; Kerin, F.; Baldwin, P.A.; Norberg, M.M. Interpersonal functioning in hoarding disorder: An examination of attachment styles and emotion regulation in response to interpersonal stress. J. Obs.-Compuls. Relat. Disord. 2018, 16, 43–49.
  104. Blom, R.M.; Samuels, J.F.; Grados, M.A.; Chen, Y.; Bienvenu, O.J.; Riddle, M.A.; Nestadt, G. Cognitive functioning in compulsive hoarding. J. Anxiety Disord. 2011, 25, 1139–1144.
  105. Frost, R.O.; Tolin, D.F.; Steketee, G.; Oh, M. Indecisiveness and hoarding. Int. J. Cogn. Ther. 2011, 4, 253–262.
  106. Paloski, L.H.; Ferreira, E.A.; Costa, D.B.; de Oliveira, C.R.; Moret-Tatay, C.; Irigaray, T.Q. Cognitive performance of individuals with animal hoarding. Health Qual. Life Outcomes 2020, 18, 40.
  107. Frost, R.O.; Hartl, T.L. A cognitive-behavioral model of compulsive hoarding. Behav. Res. Ther. 1996, 34, 341–350.
  108. Kellett, S.; Holden, K. Emotional attachment to objects in hoarding: A Critical Review of the Evidence. In The Oxford Handbook of Hoarding and Acquiring; Frost, R.O., Steketee, G., Eds.; Oxford Library of Psychology: Oxford, UK, 2014; pp. 120–138.
  109. Kings, C.A.; Moulding, R.; Knight, T. You are what you own: Reviewing the link between possessions, emotional attachment, and the self-concept in hoarding disorder. J. Obs.-Compuls. Relat. Disord. 2017, 14, 51–58.
  110. Ferreira, E.A.; Paloski, L.H.; Costa, D.B.; Moret-Tatay, C.; Irigaray, T.Q. Psychopathological comorbid symptoms in animal hoarding disorder. Psychiatr. Q. 2020, 91, 853–862.
  111. Costa, D.B.; Schütz, D.M.; de Oliveira, D.S.; Del Huerto, M.L.; Fiametti, V.S.; Dal Forno, C.; Irigaray, T.Q. Personality and psychopathological aspects in animal hoarding measured through HTP. Contextos Clínicos 2020, 13, 3–18.
  112. Colombo, E.S.; D’Amico, P.; Prato-Previde, E. Una pericolosa Arca di Noè. In L’accumulo di Animali tra Cronaca e Ricerca; Cosmopolis: Torino, Italy, 2015.
  113. Steketee, G.; Gibson, A.; Frost, R.O.; Alabiso, J.; Arluke, A.; Patronek, G. Characteristics and antecedents of people who hoard animals: An exploratory comparative interview study. Rev. Gen. Psychol. 2011, 15, 114–124.
  114. Ung, J.E.; Dozier, M.E.; Bratiotis, C.; Ayers, C.R. An exploratory investigation of animal hoard-ing symptoms in a sample of adults diagnosed with hoarding disorder. J. Clin. Psychol. 2017, 73, 1114–1125.
  115. Strong, S.; Federico, J.; Banks, R.; Williams, C. A collaborative model for managing animal hoarding cases. Appl. Anim. Welf. Sci. 2019, 22, 267–278.
  116. Calvo, P.; Duarte, C.; Bowen, J.; Bulbena, A.; Fatjó, J. Characteristics of 24 cases of animal hoarding in Spain. Anim. Welf. 2014, 23, 199–208.
  117. Ockenden, E.M.; De Groef, B.; Marston, L. Animal hoarding in Victoria, Australia: An exploratory study. Anthrozoös 2014, 27, 33–47.
  118. Nathanson, J.N. Animal hoarding: Slipping into the darkness of comorbid animal and self-neglect. J. Elder Abuse Negl. 2009, 21, 307–324.
  119. Ferreira, E.A.; Paloski, L.H.; Costa, D.B.; Fiametti, V.S.; De Oliveira, C.R.; de Lima Argimon, I.I.; Irigaray, T.Q. Animal hoarding disorder: A new psycho- pathology? Psychiatry Res. 2017, 258, 221–225.
  120. Williams, B. Animal hoarding: Devastating, complex, and everyone’s concern. Ment. Health Pract. 2014, 17, 35–39.
  121. Avery, L. From helping to hoarding to hurting: When the acts of “good Samaritans” become felony animal cruelty. Valpso. Univ. Law Rev. 2005, 39, 815–858.
  122. Campos-Lima, A.L.; Torres, A.R.; Yucel, M.; Harrison, B.J.; Moll, J.; Ferreira, G.M.; Fontenelle, L.F. Hoarding pet animals in obsessive-compulsive disorder. Acta Neuropsychiatr. 2014, 27, 8–13.
  123. Guerra, S.; Sousa, L.; Ribeiro, O. Report practices in the field of animal hoarding: A scoping study of the literature. J. Ment. Health 2021, 30, 646–659.
  124. D’Angelo, D.; Ciani, F.; Zaccherini, A.; Tafuri, S.; Aval-lone, L.; d’Ingeo, S.; Quaranta, A. Human- animal relationship dysfunction: A case study of animal hoarding in Italy. Animals 2020, 10, 1501.
  125. Emmett, L.; Kasacek, N.; Stetina, B.U. Demographic Characteristics of Individuals Who Abuse Animals: A Systematic Review. Phys. Astron. Int. J. 2021, 4, 3.
  126. Lockette, J. Cat Hoarding Is Spiraling Out of Control in the UK—Animal Experts Reveal. 2016. Available online: (accessed on 1 September 2022).
  127. Reinisch, A.I. Characteristics of six recent animal hoarding cases in Manitoba. Can. Vet. J. 2009, 50, 1069–1073.
  128. Joffe, M.; O’Shannessy, D.; Dhand, N.K.; Westman, M.; Fawcett, A. Characteristics of persons convicted for offences relating to animal hoarding in New South Wales. Aust. Vet. J. 2014, 92, 369–375.
  129. Marijana, V.; Dimitrijevic, I. Body condition and physical care scales in three cases of dog hoarding from Belgrade. Acta Vet. 2007, 57, 553–561.
  130. Cunha, G.R.D.; Martins, C.M.; Ceccon-Valente, M.D.F.; Silva, L.L.D.; Martins, F.D.; Floeter, D.; Biondo, A.W. Frequency and spatial distribution of animal and object hoarder behavior in Curitiba, Paraná State, Brazil. Cad. Saúde Pública 2017, 33, e00001316.
  131. Arnold, S.; Mackensen, H.; Ofensberger, E.; Rusche, B. Assessment of Recent Cases of Animal Hoarding in Germany: The Challenge for Animal Shelters and Public Authorities. People Anim. Int. J. Res. Pract. 2018, 1, 7.
  132. Nadal, Z.; Ferrari, M.; Lora, J.; Revollo, A.; Nicolas, F.; Astegiano, S.; Díaz Videla, M. Noah’s syndrome: Systematic review of animal hoarding disorder. HAI Bull. 2020, 10, 1–21.
  133. Saldarriaga-Cantillo, A.; Rivas Nieto, J.C. Noah syndrome: A variant of Diogenes syndrome accompanied by animal hoarding practices. J. Elder Abuse Negl. 2015, 27, 270–275.
  134. Reinisch, A.I. Understanding the human aspects of animal hoarding. Can. Vet. J. 2008, 49, 1211–1215.
  135. Patronek, G.J.; Loar, L.; Nathanson, J.N. Animal Hoarding: Strategies for Interdisciplinary Interventions to Help People, Animals, and Communities at Risk; Hoarding of Animals Research Consortium: Boston, MA, USA, 2006.
  136. Elliott, R.; Snowdon, J.; Halliday, G.; Hunt, G.E.; Coleman, S. Characteristics of animal hoarding cases referred to the RSPCA in New South Wales, Australia. Aust. Vet. J. 2019, 97, 149–156.
  137. Patronek, G.J.; Nathanson, J.N. A theoretical perspective to inform assessment and treatment strategies for animal hoarders. Clin. Psychol. Rev. 2009, 29, 274–281.
  138. Arluke, A.; Killeen, C. Inside Animal Hoarding: The Case of Barbara Erickson and Her 552 Dogs; Purdue University Press: West Lafayette, IN, USA, 2009.
  139. Hojat, M.; Vergare, M.J.; Maxwell, K.; Brainard, G.; Herrine, S.K.; Isenberg, G.A.; Gonnella, J.S. The devil is in the third year: A longitudinal study of erosion of empathy in medical school. Acad. Med. 2009, 84, 1182–1191.
  140. Neumann, M.; Edelhäuser, F.; Tauschel, D.; Fischer, M.R.; Wirtz, M.; Woopen, C.; Scheffer, C. Empathy decline and its reasons: A systematic review of studies with medical students and residents. Acad. Med. 2011, 86, 996–1009.
  141. Jolliffe, D.; Farrington, D.P. Empathy and offending: A systematic review and meta-analysis. Aggress. Violent Behav. 2004, 9, 441–476.
  142. Jolliffe, D.; Farrington, D.P. Examining the relationship between low empathy and bullying. Aggress. Behav. 2006, 32, 540–550.
  143. Berry, C.; Patronek, G.; Lockwood, R. Long-term outcomes in animal hoarding cases. Anim. Law 2005, 11, 167–194.
  144. Frost, R. People who hoard animals. Psychiatr. Times 2000, 17, 367–382.
  145. Sanders, C.R. Excusing Tactics: Social Responses to the Public Misbehavior of Companion Animals. Anthrozoos 1990, 4, 90–92.
  146. Vaca-Guzman, M.; Arluke, A. Normalizing passive cruelty: The excuses and justifications of animal hoarders. Anthrozoös 2005, 18, 338–357.
  147. Hyde, K.R.; Kurdek, L.; Larson, P.C. Relationships between pet ownership and self-esteem, social sensitivity, and interpersonal trust. Psychol. Rep. 1983, 52, 110.
  148. Purewal, R.; Christley, R.; Kordas, K.; Joinson, C.; Meints, K.; Gee, N.; Westgarth, C. Companion animals and child/adolescent development: A systematic review of the evidence. Int. J. Environ. Res. Public Health 2017, 14, 234.
  149. Lyons-Ruth, K.; Dutra, L.; Schuder, M.; Bianchi, I. From infant attachment disorganization to adult dissociation: Relational adaptations or traumatic experiences? Psychiatr. Clin. N. Am. 2006, 29, 63–86.
  150. Nathanson, J.N.; Patronek, G.J. Animal hoarding: How the semblance of a benevolent mission becomes actualized as egoism and cruelty. In Pathological Alltruism; Oakley, B., Knafo, A., Madhavan, G., Wilson, D., Eds.; Oxford University Press: New York, NY, USA, 2011; pp. 107–115.
  151. Brown, S. Theoretical concepts from self psychology applied to animal hoarding. Soc. Anim. 2011, 19, 175–193.
  152. Cassidy, J.; Mohr, J.J. Unsolvable fear, trauma, and psychopathology: Theory, research, and clinical considerations related to disorganized attachment across the life span. Clin. Psychol. Sci. Pract. 2001, 8, 275.
  153. Bowlby, J. Attachment and Loss: 1. Attachment; Basic Books: New York, NY, USA, 1969.
  154. Bowlby, J. The Making and Breaking of Affectional Bonds; Tavistock: London, UK, 1979.
  155. Tolmacz, R. Forms of concern: A psychoanalytic perspective. In Prosocial Motives, Emotions, and Behavior: The Better Angels of Our Nature; Mikulincer, M., Shaver, P.R., Eds.; American Psychological Association: Washington, DC, USA, 2010; pp. 93–107.
  156. Hesse, E.; Main, M. Disorganized infant, child, and adult attachment: Collapse in behavioral and attentional strategies. J. Am. Psychoanal. Assoc. 2000, 48, 1097–1127.
  157. Dalenberg, C.J.; Paulson, K. The case for the study of “normal” dissociation processes. In Dissociation and the Dissociative Disorders: DSM-V and Beyond; Dell, P.F., O’Neil, J.A., Eds.; Routledge: New York, NY, USA, 2009; pp. 145–154.
  158. Brown, S.E.; Katcher, A.H. The contribution of attachment to pets and attachment to nature to dissociation and absorption. Dissociation 1997, 10, 125–129.
  159. Brown, S.E.; Katcher, A. Pet attachment and dissociation. Soc. Anim. 2001, 9, 25–41.
Contributors MDPI registered users' name will be linked to their SciProfiles pages. To register with us, please refer to : , ,
View Times: 818
Revisions: 2 times (View History)
Update Date: 26 Oct 2022
Video Production Service