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Can sterilization help to prevent roaming in owned dogs and cats?

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Abstract

In many locations, the highest proportion of roaming dogs and cats, might have owners. The prevention of roaming in owned dogs and cats is a key intervention to reduce the number of unsupervised animals in public spaces. Sterilization is an important population management intervention but it is unclear if, apart from its effects on birth rates and animal behavior, it also affects the roaming status of owned dogs and cats. We formulated a directed acyclic graph to represent a causal hypothesis regarding the effect of sex, age and sterilization on roaming behavior in owned dogs and cats. The causal hypothesis was tested using survey data and Bayesian multilevel logistic regressions. The odds of roaming were lower in sterilized dogs and cats but the credible interval (CI) supported the effect of sterilization only for dogs. The odds of roaming were higher in both male dogs and cats and the CI supported the effect of sex. The CI did not support the effect of age on roaming, irrespective of species. If the observed association between sterilization and roaming was causal, then sterilization may contribute to a reduction in roaming. Studies on other populations and the exploration of other potential determinants of roaming are required to better understand the causal relationship between sterilization and roaming.

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... Roaming behavior in dogs may increase exposure to tick vectors of B. rossi, increasing risk of infection and plausibly severity of disease due to higher infectious dose. Studies have shown that gonadectomy is associated with reduced owner-reported roaming behavior in males (Maarschalkerweerd et al., 1997;Neilson et al., 1997;Baquero et al., 2020) and in females (Baquero et al., 2020); however, gonadectomy did not reduce home range size or observed roaming behavior in a study of male dogs (Garde et al., 2016) that followed large numbers of dogs continuously using global positioning system (GPS) technology. Gonadectomy in dogs has also been associated with reduced tick infestation (Raghavan et al., 2007;Smith et al., 2011) and endoparasitic infections Fig. 4. Results of the tipping point sensitivity analysis for an unmeasured confounder U for the total effect of gonadectomy on the outcome from (A) the case-control and (B) the retrospective cohort study, assuming a prevalence of 0.8 for U in the gonadectomized group. ...
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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.
Article
Free-roaming dogs (FRDs) pose a significant health threat to humans, other animals and the environment. Yet, the effects of their movements and habitat use within cities and adjacent rural areas are poorly known, especially in relation to predation and the transmission of diseases that can impact human health (i.e., cystic echinococcosis and rabies). We explored the temporal and spatial distribution of owned FRDs for a remote Patagonian city surrounded by a grasslands rural ecosystem by superimposing GPS coordinates of tracked dogs on satellite images (Google map). Using logistic regressions, we evaluated the potential effect of age, body condition score (BCS) and distance from their initial recorded GPS fix (at or near the owner's home) to the rural boundary (RD) as predictors of home range (HR) and maximum distance (MD) travelled from home. Our study revealed that owned FRDs in Puerto Natales, Chile have a high site fidelity to the urban environment and especially their owneŕs home, seldom venturing into rural areas. We observed that even FRDs living in close proximity to the city boundary spent most of their time within the urban environment. On average, FRDs had a HR of 0.65 km² (65 ha) and travelled a MD of 1.05 km. There were two individuals that travelled significantly further, and hence occupied a larger HR than the rest. Additionally, our results indicated that BCS was a predictor of HR, while age and RD were predictors of MD. These findings add to the range of predictors known to affect roaming dog HR size and used across different studies, suggesting that site-specific factors are likely affecting dog behavioral ecology. The study findings provide useful and original data on the movement ecology and site fidelity of owned FRDs in a remote city in Patagonia. We recommend that to make meaningful and cost-effective management decisions regarding owned FRDs in urban areas, future studies should also include the collection of sociocultural information on the interactions between of dogs and people.
Article
Estimates of owned dog population size are necessary to calculate measures of disease frequency and to plan and evaluate population management programs. We calculated the error and bias of estimates of the total number of owned dogs using a two-stage cluster sampling design. The estimates were conditioned on sample composition as well as on size and heterogeneity of the spatial distribution of owned dog populations. For this, we simulated nine cities that differed systematically in size (number of census tracts) and heterogeneity (variance of the number of dogs per census tract). Then, we defined 16 scenarios to calculate the sample composition using an algorithm that incorporated data from a pilot sample, estimates of cost, and prior specifications of the expected error and confidence level. In three additional scenarios of predefined sample composition, the numbers of primary and secondary sampling units were: 30 × 30, 50 × 20 and 65 × 15. Finally, for each city and sample composition, we selected primary sampling units (census tracts) with probability proportional to its size and with replacement, and secondary sampling units (households) by simple random sampling. For each city and composition we selected 500 samples, totaling 85500 samples. The distribution of errors conditioned on the sample composition and city showed that estimates were accurate (average mean bias = 0.006%, maximum mean bias = 0.3%). All sample compositions resulted in errors between 4% and 7% in cities with low heterogeneity. In cities with high heterogeneity, the errors for the various compositions ranged as follows: 8–11% (calculated), 11–13% (65 × 15), 12–14% (50 × 20) and 15–17% (30 × 30). The sample size of predefined compositions was between 33% and 87% lower than the sample size of calculated compositions. Therefore, the predefined compositions have an operational advantage (reduced sampling effort) and simplify the sampling design (calculation of sample composition is not needed). Furthermore, the expected error of estimates under different scenarios is known for each predefined composition. In the absence of information about the heterogeneity of the cities, the 65 × 15 is the more conservative composition.
Article
Objective: To estimate the home range (HR) and investigate the potential predictors for roaming of 58 dogs in four Aboriginal communities in the Northern Territory. Design: Prospective study. Procedure: Global positioning system (GPS) collars were attached to the dogs for 1-4 days, recording location fixes every 1-3 min. Utilisation distributions (UDs) and extended (95% isopleth) and core (50% isopleth) HRs of dogs were determined. Potential predictors of roaming were assessed. Results: Estimated core (median, 0.27 ha) and extended (median, 3.1 ha) HRs differed significantly (P = 0.0225 and 0.0345, respectively) between the four communities; dogs in the coastal community travelled significantly (P < 0.0001) more per day than dogs in the three inland communities studied. Significant associations were found between extended HR size and sex (P = 0.0050) and sex + neuter (P = 0.0218), and between core HR size and sex (P = 0.0010), neuter status (P = 0.0255) and sex + neuter (P = 0.0025). Entire males roamed more than neutered females. The core HR of dogs with poor/fair body condition scores (BCSs) was larger than dogs with ideal/obese BCSs (P = 0.0394). Neutered male dogs also travelled more per day than entire female dogs (P = 0.0475). Conclusions: Roaming information can be used to inform the management of dogs in remote communities and to design disease control programs. Widespread data collection across the Northern Territory should be undertaken to further investigate the associations found in this study, considering that data were collected during relatively short periods of time in one season.
Article
In many regions of the world domestic dogs are free roaming and live in close relationship with humans. These free-roaming domestic dogs (FRDD) can cause public health problems such as dog bites and transmission of infectious diseases. To effectively control diseases transmitted by FRDD, knowledge on the dogs’ behaviour is required. To identify predictors of home range (HR) size, we collected global positioning system data from 135 FRDD living in eight Aboriginal and Torres Strait Islander communities in Northern Australia. The core HR size ranged from 0·17 to 2·33 ha and the extended HR size from 0·86 to 40·46 ha. Using a linear mixed effect model with a Restricted Maximum Likelihood approach, the dog's sex and reproductive status were identified as predictors of roaming. Non-castrated males had the largest HRs, followed by neutered females. Also, FRDDs were found to roam further during the pre- than the post-wet season. These findings have implications for infectious disease spread. Identification of risk groups for disease spread within a population allows for more targeted disease response and surveillance. Further investigation of predictors of roaming in other FRDD populations worldwide would increase the external validity of such studies.
Article
Roaming pet cats Felis catus are a significant conservation issue because they may hunt, harass and compete with wildlife; spread disease, interbreed with cats in feral populations, and hybridise with wild native felids. Studies of the roaming behaviour of pet cats are often hampered by modest sample sizes and variability between cats, limiting statistical significance of the findings and their usefulness in recommending measures to discourage roaming. We resolved these difficulties through meta-analyses of 25 studies from 10 countries involving 469 pet cats to assess the influence of sex, whether a cat was desexed and housing density on roaming. A complementary linear mixed models approach used data on 311 individual animals from 22 studies and was also able to assess the influence of age and husbandry practices on roaming. This restricted sample gave greater statistical power than the meta-analyses. Meta-analyses found that: male pet cats had larger home ranges than females, desexing did not influence home range, and cats had larger home ranges when housing densities were low. The linear mixed models supported those results. They also indicated that animals ≥ 8 years old had smaller home ranges than younger cats. Cats fed regularly, provided with veterinary care and socialised with humans had similar home ranges to cats living in association with households but not provided for in some of these ways. Short of confinement, there is no simple measure owners can adopt to reduce roaming by their cats and prevent the associated environmental problems.
Article
We simulated dog population dynamics for a thirty-years period using a logistic growth model. Through sensitivity analyses, we determined the influence of the parameters used in the model. Carrying capacity was the most influential parameter in all simulations. In the owned-dog population, the influence of immigration, abandonment and births was 19%, 16% and 6% of the influence of the carrying capacity, respectively. In the sterilized owned-dog population, the influence of abandonment, female and male sterilization was 37%, 30% and 27% of the influence of the carrying capacity. In the stray population, the influence of abandonment, carrying capacity of the owned-dog population and adoption was 10%, 9% and 6% of the influence of the carrying capacity. In the sterilized stray population, the influence of births, female sterilization and male sterilization was 45%, 15% and 13% of the influence of the carrying capacity. Other parameters had lower influence values. Modification of the carrying capacity requires different interventions for the owned- and stray-dog populations. Dog trade control is a way to reduce immigration. The evaluation of sterilization effects must focus on the variations in the infertile population fraction. Adoption may improve the effects of the reduction in carrying capacity on the stray-dog population.
Article
Population management of free-roaming domestic dogs (Canis lupus familiaris) is of interest due to the threat these animals pose to people, other animals and the environment. Current sterilization procedures for male dogs include surgical and chemical methods. However, little is known about how these procedures affect their behavior. The primary objective of this study was to investigate changes in selected behaviors following chemical and surgical sterilization in a male free-roaming dog (FRD) population in southern Chile. We also examined the association between serum testosterone levels and behaviors thought to be influenced by circulating androgens. A total of 174 dogs were randomly assigned to either a surgical or chemical sterilization group, or a control group. At the onset of the intervention period, 119 dogs remained and 102 dogs successfully completed the study. Each dog was monitored pre- and post-intervention using video recordings, GPS collars, and blood samples for the measurement of testosterone. Analysis of behavior revealed that surgically castrated dogs showed no reduction of sexual activity or aggression when compared to their pre-intervention behavior. Chemically sterilized dogs showed a statistically significant increase in dog-directed aggression, but no change in sexual activity. There was no change in home range size in any groups between the pre- and post-intervention measurement. We found no consistent association between levels of serum testosterone concentration and behavioral changes in any of the groups. This study presents the first detailed behavioral observations following surgical and chemical sterilization in male FRDs. The information generated is highly relevant to communities struggling with the control of FRDs. Complementary studies to further our understanding of the effects of male sterilization on the behavioral and reproductive dynamics of FRD populations are needed.
Article
The objective of this study was to survey owners regarding the frequency and duration of their daily interactions with their indoor cats, the provision of toys and activities by cat owners and the prevalence of six selected behavior problems (aggression to owner, aggression to visitors, periuria, inappropriate defecation, inter-household cat aggression and intercat aggression to outdoor cats). The sample population was 277 clients from five veterinary practices who presented their domestic cat for anything except a behavior problem. The average number of toys and activities reported by owners per cat was seven, and the most common toys/activities used by owners in this survey were furry mice (64%), catnip toys (62%) and balls with bells (62%). Seventy-eight percent (78%) of owners reported that they leave the cat’s toy(s) available all the time. All owners reported playing with their cat, while most owners (64%) played with their cat more than two times per day and reported play bout durations of five minutes (33%) or 10 minutes (25%). Owners who reported play bout time equal to or greater than five minutes reported fewer behavior problems than those with play bouts of one minute (p<0.05). Sixty-one percent (61%) of owners reported that their cat engaged in one or more of the six selected behavior problem(s), but only 54% of the owners who reported behavior problems in their cats reported that they had talked to their veterinarian about the problem. The two most frequently reported behavior problems were aggression to owners (36%) and periuria (24%). Female cats were 50% less likely to be reported to have one or more behavior problems than males, in spite of an equal sex distribution in the survey population (p<0.05). The relationship between individual behavior problems and individual toys and activities was evaluated by use of a logistic stepwise regression. These findings are discussed as they relate to the understanding of behavioral needs of indoor-housed cats and the potential role of environmental enrichment in the home setting.
Article
A retrospective study was carried out on feline behaviour problems presented at the Animal Behaviour Clinic at the Barcelona School of Veterinary Medicine to identify the main risk factors. Three hundred thirty six cats presented for a behaviour problem between 1998 and 2006 were included in the study group. A total of 189 presented at the Hospital of the Barcelona School of Veterinary Medicine for problems other than behavioural and having no record of behaviour problems were used as control group. The main owner's complaint was aggression (47%) followed by inappropriate elimination (39%). 64% of aggression cases involved conflicts between cats and 36% of cases were aggression towards people, owners being the most common target of aggression (78% of all cases of aggression were directed towards people). Play-related aggression and petting-related aggression were the main causes of aggressive behaviour towards people (43.1 and 39.6% of cases respectively). Most housesoiling problems involved urination (59%), followed by urination and defecation (32%) and defecation (9%), and the most common diagnosis was aversion to the litterbox (63.4%). Persian cats were presented more frequently for elimination problems than other breeds (χ2=6.40; p
Article
The domestic feral cat ( Felis catus L.) is a good model for studying intraspecific variability of dispersal patterns in mammals because cats live under a large diversity of socio‐ecological conditions. We analysed both the natal and breeding dispersal patterns of domestic cats in a promiscuous urban population and tested whether or not it differed from the male‐biased natal dispersal pattern observed for polygynous rural populations. During an 8‐year study we recorded the exact date of in situ death for 148 marked cats and the exact date of disappearance from the population for 99 other cats. Because undiscovered deaths might over‐estimate dispersal probabilities when considering only disappearance probabilities, we made an novel application of multistrata capture–recapture methods in order to disentangle dispersal from true mortality. We showed that mature females dispersed, both before and after their first reproduction, at 1 and 2 years old. Contrary to females, no dispersal seemed to occur in males. Before sexual maturity, females that disappeared at 1 and 2 years old were in worse body condition than females that stayed in the population area after 2 years old. However, they did not reproduce less successfully before their disappearance than females that died later in the population area. The female‐biased and low natal dispersal pattern in this population was atypical compared to other promiscuous/polygynous mammals and differed from that observed in rural polygynous populations of domestic cat. Neither local mate competition nor inbreeding avoidance appeared to be sufficient pressures to counterbalance ecological constraints on dispersal in an urban environment. However, local resource competition for den sites between potential matriarchies could lead to the breeding dispersal of less competitive females.
Article
Reproductive behaviour of free-ranging dogsCanis familiaris Linnaeus, 1758 was studied in a village in the state of West Bengal, India. Increased synchronized breeding was the most striking feature of this study. October (late monsoon) represented the peak period of mating for the feral dogs. Of all courting males, only 41% were observed to mount and copulate. On average, each male mounted 5.47 ± 2.49 (mean ± SD) times per hour. Of all mountings, only 10% were successful matings, ie copulatory ties. There was a negative correlation between the number of courting males and the number of successful copulations. The average duration of copulatory tie was 15.73 ± 7.75 min. Several factors interrupting the duration of copulatory ties were identified. December was the peak period of pup rearing. Mean litter size was 5.70 ± 2.03 with a male-biased sex ratio 1.41:1. Only a single annual breeding cycle recorded here differed from the previous studies on European and American dogs. Mothers spent most of the time with their pups at the dens during the early stage of rearing. The duration of time spent at dens by mothers was minimum when the pups were highly mobile at the age of 10 weeks. The lactating mothers were observed to be more aggressive immediately following litter production. Typically, an old adult male remained near the den as a ‘guard’. Key words Canis familiaris -sexual behaviour-copulatory tie-breeding
Article
The attitudes and behaviours of cat owners in regard to treatment of cats may have a cumulative effect on the food availability, reproduction, density and welfare of the free-roaming cat population and thus also on the extent of cat overpopulation. Understanding this is thus a vital step in the a priori planning of cat management programs on any scale, as well as in developing public education programs on this issue. Although recent years have seen an accumulation of knowledge in regard to cat owners' attitudes and behaviours, the findings vary among countries and locations and in Israel this has never been investigated systematically. Using a questionnaire provided to cat owners in veterinary clinics, this study aimed at identifying those attitudes and behaviours that may be contributing to cat overpopulation in Tel Aviv, Israel, and at exploring the socio-economic factors that influence this problem. The findings show that the influential factors can be predicted from the cat owners' socio-economic status, mainly education and income, as well as gender and age. A consistency in those cat owner behaviours that contribute to cat overpopulation was also uncovered, revealing a sub-population of individuals who persist in the undesirable behaviours. Finally, a strong relationship between attitude and consequent behaviour was demonstrated, indicating the importance of education and targeted publicity as a means to influence attitudes and thereby change behaviours in this respect. We propose several measures by which to reduce the current extent of cat owners' contribution to the cat overpopulation: discouraging unwanted owner behaviours such as abandonment of their cats and allowing them to breed; promoting awareness of the neutering option among cat caretakers; and increasing pre-adoption neutering rates in shelters. Regional and national laws promoting responsible pet ownership need to be enacted. By improving the current level of knowledge and awareness among cat owners regarding cat overpopulation issues, and encouraging a more responsible attitude, cat owners' bond with their cats could be strengthened, as well as their bond with and contribution to their environment.
Article
Dogs and cats are important members of many families; however, they can harbour gastrointestinal parasites that may infect their owners. Some of these parasites, e.g. Echinococcus sp., can have a significant impact on human health. However, with appropriate education, management and anthelmintic regimes, zoonotic transmission of these parasites can be minimised.
Article
Recent outbreaks of rabies and canine distemper in wildlife populations of the Serengeti show that infectious disease constitutes a significant cause of mortality that can result in regional extirpation of endangered species even within large, well-protected areas. Nevertheless, effective management of an infectious disease depends critically on understanding the epidemiological dynamics of the causative pathogen. Pathogens with short infection cycles cannot persist in small populations in the absence of a more permanent reservoir of infection. Development of appropriate interventions requires detailed data on transmission pathways between reservoirs and wildlife populations of conservation concern. Relevant data can be derived from long-term population monitoring, epidemic and case-surveillance patterns, genetic analyses of rapidly evolving pathogens, serological surveys, and intervention studies. We examined studies of carnivore diseases in the Serengeti. Epidemiological research contributes to wildlife conservation policy in terms of management of endangered populations and the integration of wildlife conservation with public health interventions. Long-term, integrative, cross-species research is essential for formulation of effective policy for disease control and optimization of ecosystem health.
R Package to Process Selected Outputs form the INLA Package
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Baquero, O.S., 2018. R Package to Process Selected Outputs form the INLA Package. Retrieved from: https://github.com/oswaldosantos/INLAOutputs.
Guidelines for Dog Populations Management. World Health Organization
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Bögel, K., Frucht, K., Drysdale, G., Remfry, J., 1990. Guidelines for Dog Populations Management. World Health Organization, Geneva.
The Bio-Ecology of Dogs and Implementation of radiotelemetry Technology to Determine Dog Home Ranges in Conjunction with Rabies Vaccination Programs in the District of Badung
  • I K Gunata
Gunata, I.K., 2011. The Bio-Ecology of Dogs and Implementation of radiotelemetry Technology to Determine Dog Home Ranges in Conjunction with Rabies Vaccination Programs in the District of Badung, Bali. Udayana University Bali, Indonesia.
Risks and Benefits to Cats of Free Roaming Versus Containment
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Kasbaoui, N., 2016. Risks and Benefits to Cats of Free Roaming Versus Containment. University of Lincoln.
Tidyverse: Easily Install and Load the 'Tidyverse
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