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Effects of castration on problem behaviors in male dogs with reference to age and duration of behavior
Abstract
To determine whether 9 problem behaviors in adult male dogs were affected by castration and to examine the influence of age and duration of problem behavior on behavioral effects of castration.
Cohort study.
57 male dogs > 2 years old at the time of castration that had > or = 1 of the targeted problem behaviors.
Data were collected by telephone contact with owners to identify dogs that had > or = 1 problem behavior before castration and to estimate the improvement (ie, decrease) in the objectionable behaviors after castration. Problem behaviors of interest included urine marking in the house, mounting, roaming, fear of inanimate stimuli, aggression toward human family members, aggression toward unfamiliar people, aggression toward other dogs in the household, aggression toward unfamiliar dogs, and aggression toward human territorial intruders.
Effects of castration on fear of inanimate stimuli or aggression toward unfamiliar people were not significant. For urine marking, mounting, and roaming, castration resulted in an improvement of > or = 50% in > or = 60% of dogs and an improvement of > or = 90% in 25 to 40% of dogs. For remaining behaviors, castration resulted in an improvement of > or = 50% in < 35% of dogs. Significant correlations were not found between the percentage of improvement and age of the dog or duration of the problem behavior at the time of castration.
Castration was most effective in altering objectionable urine making, mounting, and roaming. With various types of aggressive behavior, including aggression toward human family members, castration may be effective in decreasing aggression in some dogs, but fewer than a third can be expected to have marked improvement. Age of the dog or duration of the problem behavior does not have value in predicting whether castration will have a beneficial effect.
... A literature review shows that the behavior of intact and castrated dog populations has been compared in several research studies [3,[20][21][22]. However, to the best of our knowledge, the only study analyzing the impact of castration on problematic behaviors in dogs was conducted by Neilson et al. [23] in a small group of 57 dog owners. The aim of the present study was to identify the reasons for male dog castration and to determine the owners' perceptions about changes in dog behavior before and after castration in a larger group of respondents. ...
... Puppies and young adults recover more rapidly after castration [27], but every surgical procedure increases the risk of parvoviral infection and hip dysplasia [28]. According to Neilson et al. [23], the age at castration does not correlate with the percentage of improvement in problematic behavior. ...
... In the present study, most dogs were castrated to reduce the prevalence of undesirable behaviors (Figure 1), which is consistent with the findings of other authors [23,29,30]. Maarschalkerweerd et al. [29] observed that the most common behavioral reasons for castration were mounting directed towards people, other dogs and objects, followed by roaming, aggression, marking and fear. ...
In many Western countries, castration is the most popular surgical desexing procedure in dogs. The aim of the study was to identify the reasons for male dog castration and to determine the owners’ perceptions about changes in dog behavior before and after castration. An online survey was posted on social networking sites dedicated to dogs. A total of 386 respondents participated in the survey. The main reason (39%) for castration was undesirable behavior, including hyperactivity (8%), roaming (8%), mounting (7%), aggression (5%), marking (5%) and others (5%). This surgery did not change the prevalence of aggressive behaviors towards people, but it reduced aggressive behaviors towards dogs and other animals. Castration did not reduce the presentation of anxious behavior in fearful dogs. Castration increased the number of dogs that were fearful of unfamiliar dogs/humans, as well as dogs with sound phobias, while decreased the prevalence of hiding behavior. This procedure greatly decreased incidences of roaming, mounting and urine marking as well as the dog’s overall activity. Thus, it can be concluded that while castration can resolve many undesirable behaviors in male dogs, the arguments for and against neutering should always be considered on an individual basis.
... The role of gonadectomy on behavior is complex and evidence for benefits as well as detriments following gonadectomy has been reported. Reproductive-related behaviors (such as urine marking in house, mounting, and roaming) are all reduced or eliminated following gonadectomy [86,87,29].However, fear and aggression tend to be exacerbated [88]. ...
... Gonadectomized females are also more reactive to the presence of unfamiliar humans and dogs [89]. Although some dogs may become less aggressive following gonadectomy [90], dominance aggression [87]and ownerdirected aggression [20,91] occur with a significantly higher frequency in gonadectomized dogs compared to unaltered dogs. The hippocampus and hypothalamus both play important roles in controlling behaviors, especially those pertaining to fear and aggression. ...
Throughout most of the developed world, surgical sterilization via gonadectomy has become a common tool for combating the overpopulation of unwanted dogs as well as to eliminate the risk of reproductive diseases in pet dogs. However, if a surgical sterilization method is chosen that enables a dog to keep its gonads intact while still preventing reproduction, thismay avoid the problems discussed in this article. In the dog as in other normal adult mammals, the hypothalamus secretes gonadotropin-releasing hormone (GnRH), which stimulates the anterior pituitary gland to release of luteinizing hormone. Luteinizing hormone (LH) stimulates the secretion of gonadal steroid hormones (testosterone in males and estrogen/progesterone in females). These gonadal steroid hormones then negatively feedback to the hypothalamus and anterior pituitary to decrease the secretion of GnRH and LH, respectively. However, in the gonadectomized mammal, there is no negative feedback, which results in supraphysiologic circulating concentrations of LH. In gonadectomized dogs, LH concentrations are more than thirty times the concentrations found in normal adult dogs. Although the main role of LH is for reproductive functions (e.g. ovulation, corpus luteum formation), there are LH receptors present throughout the body, not just limited to the reproductive tract. The purpose of LH receptors in non-reproductive tissues is not known but may induce cell division and stimulate nitric oxide release. With constant activation following gonadectomy, these receptors are up regulated, further magnifying the effects of the extremely high LH concentrations in non-reproductive tissues. Canine gonadectomy increases the risk of several non-reproductive long-term disorders caused by extremely high LH including obesity, urinary incontinence, urinary calculi, diabetes mellitus, hypothyroidism, hip dysplasia, cranial cruciate ligament rupture, aggressive and fearful behavior, cognitive dysfunction syndrome, prostate adenocarcinoma, transitional cell adenocarcinoma, osteosarcoma, hemangiosarcoma, lymphosarcoma, and mastocytoma. In this review, the relationship between LH receptor activation in these non-reproductive target tissues will be discussed.
... 81 One small (n=57) low-quality study of domestic dogs in California in 1997, found a small percentage of owners (10%-25%) demonstrated a substantial (90%) reduction in aggressive behaviours toward following surgical sterilisation. 63 A further similar study in 23 household dogs in the USA found a 26% reduction in aggression indoors and a 52% reduction outdoors. 59 However, these studies were limited by small sample sizes, lack of a control group and subjective ownerreported measures of aggression which are likely subject to bias. ...
Background
The prevention of dog bites is an increasingly important public health topic, as the incidence of serious injury continues to rise.
Objectives
To evaluate the effectiveness of interventions to prevent dog bites and aggression.
Methods
Online databases were searched (PubMed, Cochrane Library, Embase, and Google Scholar), using the search terms: dog/s, canine, canis, kuri, bite/s, bitten, aggression, attack, death, fatal, mortality, injury/ies, prevention, intervention, for studies between 1960–2021. All study designs were considered. Outcomes of interest were the incidence of dog bites or dog aggression. Non-English studies, and those without full-text access were excluded.
Results
Forty three studies met the review criteria, including 15 observational and 27 interventional studies. Fifteen studies investigating dog-control legislation, including leash laws, stray dog control and infringements indicated this can reduce dog bite rates. Breed-specific legislation had less of an effect. Six studies investigating sterilisation, showed while this may reduce dog bites through a reduction in the dog population, the effect on dog aggression was unclear. An alcohol reduction programme showed a significant reduction in dog bite rates in one study. Seven studies assessing educational approaches found that intensive adult-directed education may be effective, with one study showing child-directed education was not effective. Eight studies on dog training (two police-dog related), and six evaluating dog medication or diet were generally low quality and inconclusive.
Conclusions
Multiple strategies including effective engagement with indigenous communities and organisations will be required to reduce dog-bites and other incidents involving dog aggression. This review provides some evidence that legislated dog control strategies reduce dog bite rates. Available evidence suggests greater restrictions should be made for all dogs, rather than based on breed alone. Due to a burden of child injury, protection of children should be a focus of legislation and further investigations. Prevention strategies in children require redirection away from a focus on child-directed education and future research should investigate the effectiveness of engineering barriers and reporting strategies.
... However, surgical castration is a major invasive procedure and irreversible. Furthermore, behavioural problems, attributed to the influence of androgens, are not always solved by surgical castration (Maarschalkerweerd et al., 1997;Neilson et al., 1997;Roulaux et al., 2020). Therefore, a reversible therapy is considered desirable for these indications. ...
Abstract
Chemical castration, that is the reduction of circulating testosterone concentrations
to castrate levels by administration of a GnRH-agonist
implant, is a popular alternative to surgical castration in male dogs. Detailed information concerning the pituitary-testicular axis following administration of a GnRH-agonist
implant is still scarce. Therefore, GnRH-stimulation tests were performed in male dogs, prior to and after surgical and chemical castration. This approach also allowed us to determine plasma concentrations of testosterone and oestradiol in intact male dogs for future reference and to directly compare the effects of surgical and chemical castration on the pituitary-testicular axis. In intact male dogs (n = 42) of different breeds GnRH administration induced increased plasma LH, FSH, oestradiol and testosterone concentrations. After...
... Despite the widespread view that surgical or medical sterilization at an early age eliminates problematic behavior in both male and female dogs [39,40], recent studies show that this view may not be valid for some behavioral problems, namely those not caused by testosterone. There is even some concern that prepubertal sterilization may increase the likelihood of behavioral disorders [41][42][43]. ...
The search for an alternative approach of estrus control (induction or suppression) in dogs is an important issue and the use of slow GnRH agonist-releasing implants has been the subject of frequent research in recent years. Studies to date demonstrate that the short- and long-term effects of deslorelin implants applicated at different time points of the prepubertal period are similar to those of adult dogs; however, there are important differences. The age of the prepubertal bitch and the dosage appear to be the main determinants of the response to deslorelin, as well as the individual metabolism of the bitch. Recent studies reported that the deslorelin-mediated long-term delay of puberty does not have negative carry-over effects on subsequent ovarian functionality, serum steroid hormone concentrations, uterine health, and fertility; however, more molecular studies are needed to determine the effects of application time of GnRH agonists on hormone concentrations and peripheral receptor expression. Furthermore, the long-term effects of delay of puberty with deslorelin on joint health, tumor development, the immune system, and social behavior deserve further investigations.
... Contrary to common thinking, there is evidence that neutered dogs do not reduce their aggressive tendencies under certain circumstances. This argument was analyzed by Neilson et al. [23], who evaluated 57 males that were castrated in an attempt to reduce their aggression before they reached two years of age. They found that only 30% of the animals reduced that behavior, while the other 70% continued to manifest it. ...
Throughout history it has been common to practice activities which significantly impact on animal welfare. Animal fighting, including dogfighting, is a prime example where animals often require veterinary care, either to treat wounds and fractures or to manage pain associated with tissue and where death may even result. Amongst the detrimental health effects arising are the sensory alterations that these injuries cause, which not only include acute or chronic pain but can also trigger a greater sensitivity to other harmful (hyperalgesia) or even innocuous stimuli (allodynia). These neurobiological aspects are often ignored and the erroneous assumption made that the breeds engaged in organized fighting have a high pain threshold or, at least, they present reduced or delayed responses to painful stimuli. However, it is now widely recognized that the damage these dogs suffer is not only physical but psychological, emotional, and sensory. Due to the impact fighting has on canine welfare, it is necessary to propose solution strategies, especially educational ones, i.e., educating people and training veterinarians, the latter potentially playing a key role in alerting people to all dog welfare issues. Therefore, the aim of this review is to describe the risk factors associated with dogfighting generally (dog temperament, age, sex, nutrition, testosterone levels, environment, isolation conditions, socialization, education, or training). A neurobiological approach to this topic is taken to discuss the impact on dog pain and emotion. Finally, a general discussion of the format of guidelines and laws that seek to sanction them is presented. The role that veterinarians can play in advancing dog welfare, rehabilitating dogs, and educating the public is also considered.
OBJECTIVE
To compare health and behavior outcomes for dogs that underwent vasectomy or ovary-sparing spay (hysterectomy) with sexually intact dogs or dogs that had undergone traditional castration or spay.
SAMPLE
6,018 dog owners responded to a web-based survey between November 3, 2021, and January 7, 2022.
PROCEDURES
Participants were asked demographic questions and to provide information about 1 or more dogs (living or deceased). Options for reproductive status were as follows: sexually intact, castrated, spayed (ovariohysterectomy or ovariectomy), vasectomy, or ovary-sparing spay (hysterectomy). Participants were asked questions about orthopedic and other health problems, cancer, and problematic behavior. Logistic regression models, survival analyses, and descriptive statistics were used to assess relationships between reproductive status and outcomes.
RESULTS
Owners provided valid surveys for 6,018 dogs, including 1,056 sexually intact, 1,672 castrated, and 58 vasectomized male dogs and 792 sexually intact, 2,281 spayed, and 159 female dogs that had undergone ovary-sparing spay. Longer exposure to gonadal hormones, regardless of reproductive status, was associated with reduced odds of general health problems and both problematic and nuisance behaviors.
CLINICAL RELEVANCE
TTo our knowledge, this study provides the first data on health and behavior outcomes of vasectomy and ovary-sparing spay in dogs and is the first to compare these outcomes to sexually intact and gonadectomized dogs. It adds to accumulating data on the mixed benefits and risks of removing the gonads to prevent reproduction and emphasizes the importance of developing an informed, case-by-case assessment of each patient, taking into consideration the potential risks and benefits of spaying or neutering and alternative reproductive surgeries.
Domestic dogs differ enormously in both their morphology and behavior. Numerous factors can influence the development and expression of canine behavior and, more generally, determine the success of the pet–owner relationship. This chapter considers the role of nature and nurture in shaping canine behavior. The influence of factors intrinsic to the animal is outlined, focusing on research that has explored the role of breed, sex, and cerebral lateralization in guiding canine behavior and cognitive functioning. The chapter goes on to consider the role of more extrinsic factors that can influence the development of dog behavior, discussing the contribution of early experience, source of acquisition, training techniques, and owner-related traits including personality and attachment style. The article points to the enormous amount of individual variation that exists between dogs and the myriad of factors that can work together to shape the behavior and functioning of the animal we see before us.
Behavior can change as a result of medical problems or physiological changes, and behavior changes are likely to be the first signs of stress, disease, and poor welfare in any animal. If shelter operations, behavior, and/or medical staff identify behaviors that may have an underlying medical cause, they can be addressed immediately, relieving suffering and increasing the adoptability of the animal. Conversely, if medical conditions that cause or exacerbate problematic behaviors are missed, time may be wasted on training or attempted behavior modification, thus prolonging suffering and time spent in the shelter. Only by safeguarding both physical and emotional health can we improve overall quality of life for animals in our care, facilitate their placement in homes, and help prevent their return to the shelter.