Disentangling the link between supplemental feeding, population density, and the prevalence of pathogens in urban stray cats

Navigating the controversy: Public perspectives on free-roaming cat populations and control strategies in Israel

The debate surrounding the management of free-roaming cat populations is multifaceted, with conflicting views between conservationists and cat advocates. In Israel, which is characterized by densely populated free-roaming cat communities, cat numbers remain high despite extensive Trap-Neuter-Return (TNR) efforts. Recognizing the importance of public engagement for ensuring success of control campaigns, we aimed to gather public opinion on the free-roaming cat phenomenon and control strategies. Interviews were conducted with 700 randomly selected passersby at central bus and train stations nationwide. A notable fraction (223, 31.9 %) of the participants reported feeding free-roaming cats at least once during the month preceding the survey. Two sub-groups of dedicated feeders were identified: eighty feeders (11.4 %) who reported feeding on a daily basis, and forty-one (5.9 %) 'heavy' feeders who reported feeding more than ten cats. While feeders and non-feeders of free-roaming cats shared similar characteristics, daily feeders were generally older, and fewer were Israeli-born. 54 % of all participants and 45 % of the dedicated feeders considered free-roaming cats as a negative phenomenon. However, feeders typically regarded feeding free-roaming cats as beneficial (75 % strongly agreed with feeding free-roaming cats), while non-feeders exhibited a more ambivalent attitude (30 % disagreed and 35 % strongly agreed with feeding actions). Remarkably, both feeders and non-feeders agreed that the numbers of free-roaming cats should be reduced (77.3 % of all participants). In addition, most participants (62 % of all participants) agreed at least partially with the application of neutering as a cat population management tool, while the vast majority (90 % of all participants) rejected the idea of culling. In conclusion, the general public perceives free-roaming cats negatively, and as a consequence, there is widespread support for the necessity to reduce cat numbers. However, the strong association between abundance of vital resources, such as food provided by feeders, and the cat population dynamics, is not understood or disregarded by both feeder and non-feeders of free-roaming cats. Authorities should therefore consider combining cat control programs with public education campaigns to raise public awareness of this issue.

Density and Home Range of Cats in a Small Inhabited Mediterranean Island

There is growing concern about effectively controlling cat populations due to their impact on biodiversity, especially on islands. To plan this management, it is essential to know the cat population size, sterilization rates, and space they use. Small inhabited islands can have very high cat densities; thus, this study aimed to evaluate cat density and home range on a small tourist island in the Spanish Mediterranean. Surveys in the urban area identified individual cats using a photographic catalog, and camera trapping was conducted in the scrubland area. GPS devices were fitted on three urban cats. The overall cat density was estimated to be 308 cats/km2, varying between the urban area (1084 cats/km2) and the uninhabited scrubland (27 cats/km2). Urban cats had smaller average home ranges (0.38 ha or 1.25 ha, depending on the estimation method) compared to scrubland cats (9.53 ha). Penetration of scrubland cats into the urban area was not detected. These results indicate that the urban area acts as a source of cats for the scrubland. Although the total sterilization rate was high (90.3%), the large cat population implies that the density would take over a decade to decrease to acceptable levels. Therefore, complementary measures for managing this cat population are recommended.

Prospective Investigation of Feline Leukemia Virus Infection in Stray Cats Subjected to a Trap-Neuter-Return Program in Switzerland

Feline leukemia virus (FeLV) remains a serious concern in some countries despite advances in diagnostics and vaccines. FeLV-infected cats often have reduced lifespans due to FeLV-associated diseases. The infection is transmitted through social interactions. While Northern European countries have reported a decrease in FeLV among pet cats, Switzerland's rates remain stagnant at 2.7% (2016/17: 95% CI 1.4-5.2%). Research on FeLV in Swiss stray cats has been lacking, even though these animals could serve as a virus reservoir. Sampling stray cats that do not receive regular veterinary care can be challenging. Collaboration with the Swiss Network for Animal Protection (NetAP) allowed for the prospective collection of saliva samples from 1711 stray cats during a trap-neuter-return program from 2019 to 2023. These samples were tested for FeLV RNA using RT-qPCR as a measure for antigenemia. Viral RNA was detected in 4.0% (95% CI 3.1-5.0%) of the samples, with 7.7% (95% CI 4.9-11.3%) in sick cats and 3.3% (95% CI 2.4-4.4%) in healthy ones. We identified three geographically independent hotspots with alarmingly high FeLV infection rates in stray cats (up to 70%). Overall, including the previous data of privately owned cats, FeLV-positive cats were scattered throughout Switzerland in 24/26 cantons. Our findings underscore welfare concerns for FeLV infections among stray cats lacking veterinary attention, highlighting the potential risk of infection to other free-roaming cats, including those privately owned. This emphasizes the critical significance of vaccinating all cats with outdoor access against FeLV and developing programs to protect cats from FeLV infections.

The Global Molecular Prevalence of Bartonella spp. in Cats and Dogs: A Systematic Review and Meta-Analysis

Bartonella species are vector-borne infectious pathogens with a severe impact on animal and human health. This comprehensive systematic review aimed to perform a meta-analysis to evaluate the global impact of this pathogen on pet health. A literature search was performed on electronic databases (Web of Science, PubMed, and Scopus) to find relevant peer-reviewed published papers (n = 131). A random-effects model was employed to calculate pooled prevalence estimates, and Q-statistic and I 2 index were used to assess the heterogeneity. Based on 20.133 cats and 9.824 dogs, the global prevalence estimates were 15.3% and 3.6%. The heterogeneity was significantly high in both species, with I 2 = 95.8%, p-value <0.0001, and I 2 = 87.7%, p-value <0.0001 in cats and dogs, respectively. The meta-analysis conducted using location coordinates showed a consistently high prevalence in regions located between latitudes -40 to -30 or latitudes 30-40 in both populations, in agreement with the pure spatial analysis results, which computed significantly high relative risk areas within these region coordinates. When analyzing cat data for other subgroup moderators, Bartonella spp. prevalence was higher in animals of young age (<1 year, p-value = 0.001), with a free roaming lifestyle (p-value <0.0001) and/or having ectoparasite infestation (p-value = 0.004). Globally, among the Bartonella species detected in cats, Bartonella henselae was the most frequent (13.05%), followed by Bartonella clarridgeiae (1.7%) and Bartonella koehlerae (0.11%). When considering Bartonella henselae genotype distribution, high heterogeneity (p < 0.0001) was observed based on geographical subgroups. Dogs displayed infection by Bartonella vinsonii subsp. berkhoffii (1.1%), B. henselae (1%), Candidatus B. merieuxii (0.9%) and B. rochalimae (0.38%). The present study provides a global picture of the epidemiological distribution of Bartonella spp. in cat and dog populations that may be pivotal for implementing proper preventive and control measures.

Population Dynamics of Community Cats Living in a Tourist Area of Onomichi City, Japan, before and after the Trap-Test-Vaccinate-Alter-Return-Monitor Event

The community cat program (CCP) was recommended by the Ministry of the Environment to reduce cats in local animal shelters and improve stray cat welfare in Japan. It is a non-lethal control measure with stray cats cared for as free-roaming cats for their lifetime in the community, while Trap-Neuter-Return (TNR) or Trap-Test-Vaccinate-Alter-Return-Monitor (TTVARM) activities are carried out. In the CCP, community cat colonies are hypothesized to be closed and static populations. However, it remains unknown whether the cats stay in the colonies, without migration of non-neutered cats following TNR/TTVARM events. We examined the population dynamics of cats before and after a TTVARM event using route censuses (107 days), fixed-point observations, and GPS-tracking in a tourist area in Onomichi. Eleven out of the 30 cats remained in the CCP areas, whereas 13 non-neutered cats immigrated into the CCP areas, within a year, suggesting the CCP program has limited efficacy. Besides, the program cannot support the lifetime management of the cats due rapid turnover of cats. Our results reject the CCP hypothesis, so that the program neither restricts cat breeding nor enhances cat welfare.

Occurrence of Chlamydia spp. in Conjunctival Samples of Stray Cats in Timișoara Municipality, Western Romania

Despite the widespread public health concern about stray cats serving as reservoirs for zoonotic agents, little is known about the effect of urban and peri-urban landscapes on exposure risk. We conducted this study to monitor the presence of Chlamydia spp. in stray cats, with or without conjunctivitis, living in Timișoara Municipality, Western Romania, using staining and PCR methods. A total of 95 cats were enrolled, and conjunctival samples were harvested from 68 clinically healthy cats and another 27 cats presenting with clinical signs of conjunctivitis. Overall, we found that 65.3% (62/95) of the cats tested positive for Chlamydia spp. by PCR. Chlamydia spp. were detected in 45/95 conjunctival samples using a standard Giemsa stain, compared with 62/95 using PCR (Cohen’s kappa index = 0.308; p = 0.0640). Of the cats that tested positive by PCR, 72.6% (45/62) were asymptomatic, and another 27.4% (17/62) expressed clinical signs of conjunctivitis. We found no significant difference between (p > 0.05) the distribution of infection and the recorded epidemiological data (sex, breed, age, territorial distribution, or sampling season). However, the Chlamydia spp. detection frequency was significantly higher in asymptomatic than in symptomatic cats (p = 0.0383). The obtained results increase the level of concern and awareness about the possible zoonotic potential of this pathogen and highlight that urban stray cats can be essential sources of feline chlamydiosis.

Human influences shape the first spatially explicit national estimate of urban unowned cat abundance

Globally, unowned cats are a common element of urban landscapes, and the focus of diverse fields of study due to welfare, conservation and public health concerns. However, their abundance and distribution are poorly understood at large spatial scales. Here, we use an Integrated Abundance Model to counter biases that are inherent in public records of unowned cat sightings to assess important drivers of their abundance from 162 sites across five urban towns and cities in England. We demonstrate that deprivation indices and human population densities contribute to the number of unowned cats. We provide the first spatially explicit estimates of expected distributions and abundance of unowned cats across a national scale and estimate the total UK urban unowned cat population to be 247,429 (95% credible interval: 157,153 to 365,793). Our results provide a new baseline and approach for studies on unowned cats and links to the importance of human-mediated effects.

Occurrence of Chlamydiaceae and Chlamydia felis pmp9 Typing in Conjunctival and Rectal Samples of Swiss Stray and Pet Cats

Chlamydia (C.) felis primarily replicates in feline conjunctival epithelial cells and is an important cause of conjunctivitis in cats. Data on C. felis infection rates in stray cats in Switzerland has been missing so far. We performed a qPCR-based Chlamydiaceae-screening on 565 conjunctival and 387 rectal samples from 309 stray and 86 pet cats followed by Chlamydia species identification and C. felis typing using the gene pmp9, which encodes a polymorphic membrane protein. Overall, 19.1% of the stray and 11.6% of the pet cats were Chlamydiaceae-positive with significantly higher rates in cats displaying signs of conjunctivitis (37.1%) compared to healthy animals (6.9%). Rectal shedding of Chlamydiaceae occurred in 25.0% of infected cats and was mostly associated with concurrent ocular positivity (87.5%). In 92.2% of positive conjunctival and rectal samples, the Chlamydia species was identified as C. felis and in 2.6% as C. abortus. The C. felis pmp9 gene was very conserved in the sampled population with only one single-nucleotide polymorphism (SNP) in one conjunctival sample. In conclusion, C. felis strains are circulating in Swiss cats, are associated with conjunctivitis, have a low pmp9 genetic variability, and are rectally shed in about 16% of positive cases.

What's New in Feline Leukemia Virus Infection

Feline leukemia virus (FeLV) is a retrovirus with global impact on the health of domestic cats that causes tumors (mainly lymphoma), bone marrow disorders, and immunosuppression. The importance of FeLV is underestimated due to complacency associated with previous decline in prevalence. However, with this comes lowered vigilance, which, along with potential for regressively infected cats to reactivate viremia and shed the virus or develop clinical signs, can pose a risk to feline health. This article summarizes knowledge on FeLV pathogenesis, courses of infection, and factors affecting prevalance, infection outcome, and development of FeLV-associated diseases, with special focus on regressive FeLV infection.

Subsidised by junk foods: factors influencing body condition in stray cats (Felis catus)

Domestic cats (Felis catus) are one of the most widely distributed and successful carnivores globally. While cats are popular pets, many unowned, ‘stray’ cats live freely in anthropogenic environments at high densities where they make use of anthropogenic resources. These stray cats present a management challenge due to concerns about wildlife predation, pathogen transmission, public nuisance and threats to cat welfare (e.g. vehicle collisions). In Australia, there are few studies of strays compared with pet cats or feral cats (free-roaming cats in rural areas that are independent of resources provided by humans). To contribute original data about stray cat biology, the carcasses of 188 euthanised stray cats were collected from Perth, Western Australia. Cats were assessed for general health, age, reproduction, diet and gastrointestinal parasite biomass. The influence of cat demographics, collection location, season, parasite biomass, diet and history of supplemental feeding by people were tested against body condition. Overall, strays were physically healthy and reproductive, with few life-threatening injuries or macroscopic evidence of disease; however, helminths were extremely common (95% of cats) and pose a threat. Nearly 40% of strays consumed wildlife, including two species of endemic marsupial. Alarmingly, 57.5% of strays were scavenging vast amounts of refuse, including life-threatening items in volumes that blocked their gastrointestinal tracts. These findings illustrate that strays need to be removed from anthropogenic environments for their own health and welfare and to prevent continued breeding. Targeted control programmes should prioritise removal of cats from areas where refuse is common and where valued native fauna exist.

A Case of Letting the Cat out of The Bag-Why Trap-Neuter-Return Is Not an Ethical Solution for Stray Cat (Felis catus) Management

Trap-Neuter-Return (TNR) programs, in which stray cats are captured, neutered and returned to the environment are advocated as a humane, ethical alternative to euthanasia. We review the TNR literature in light of current debate over whether or not there should be further TNR trials in Australia. We revisit the problems arising from stray cats living in association with human habitation and estimate how many stray cats would have to be processed through a scientifically-guided TNR program to avoid high euthanasia rates. We also identify 10 ethical and welfare challenges that have to be addressed: we consider the quality of life for stray cats, where they would live, whether the TNR process itself is stressful, whether TNR cats are vulnerable to injury, parasites and disease, can be medically treated, stray cats' body condition and diet, and their impacts on people, pet cats, and urban wildlife, especially endemic fauna. We conclude that TNR is unsuitable for Australia in almost all situations because it is unlikely to resolve problems caused by stray cats or meet ethical and welfare challenges. Targeted adoption, early-age desexing, community education initiatives and responsible pet ownership have greater promise to minimize euthanasia, reduce numbers rapidly, and address the identified issues.