Genetics of randomly bred cats support the cradle of cat domestication being in the Near East.

Cat domestication likely initiated as a symbiotic relationship between wildcats (Felis silvestris subspecies) and the peoples of developing agrarian societies in the Fertile Crescent. As humans transitioned from hunter-gatherers to farmers ~12,000 years ago, bold wildcats likely capitalized on increased prey density (i.e., rodents). Humans benefited from the cats' predation on these vermin. To refine the site(s) of cat domestication, over 1000 random-bred cats of primarily Eurasian descent were genotyped for single-nucleotide variants and short tandem repeats. The overall cat population structure suggested a single worldwide population with significant isolation by the distance of peripheral subpopulations. The cat population heterozygosity decreased as genetic distance from the proposed cat progenitor's (F.s. lybica) natural habitat increased. Domestic cat origins are focused in the eastern Mediterranean Basin, spreading to nearby islands, and southernly via the Levantine coast into the Nile Valley. Cat population diversity supports the migration patterns of humans and other symbiotic species.

COVID-19 associated reduction in elective spay-neuter surgeries for dogs and cats.

The rise in subsidized spay-neuter access helped drive the euthanasia of shelter pets in the US from an estimated 13. 5 million in 1973 to 1.5 million in 2019. When the arrival of the COVID-19 pandemic triggered lockdowns beginning in March 2020, many veterinary providers suspended nonessential services such as routine spay-neuter surgeries. The purpose of this study was to determine the impact of the COVID-19 pandemic on the volume of spay-neuter procedures performed by spay-neuter clinics. A retrospective study of patient data from 212 spay-neuter clinics using Clinic HQ practice management software was conducted from January 2019 through December 2021. The clinics collectively performed 1,217,240 surgeries in the pre-COVID baseline year of 2019. A sharp decline in surgeries began in March 2020 (-22%) and reached a nadir in April 2020 (-80%). Surgeries began to increase in May 2020 (-39%), before plateauing in July 2020 (-6%) and remaining slightly below the 2019 baseline in most months through the end of 2021. Compared to 2019, total surgeries decreased 13% to 1,059,388 in 2020 and decreased 3% to 1,184,274 in 2021. In 2020, when clinic disruptions were highest, the impact of the surgery cutbacks varied by geographic region, species, age, and source of animals. Compared with 2019, in 2020 surgeries decreased 17% in the Midwest region, 15% in the Northeast and West, and 11% in the South. Surgeries were reduced 19% in dogs and 10% in cats. When grouped by age, surgeries were reduced by 18% in geriatrics, 14% in adults, and 11% in juveniles. Reductions were similar for females (-14%) and males (-12%) and similar for unowned/organization-owned animals (-14%) and privately owned animals (-12%). In total, 190,818 fewer surgeries were performed by the 212 studied clinics in the 24 months from January 2020 through December 2021 than would be expected had 2019 levels been maintained. If a similar pattern was experienced by other spay/neuter providers in the US, it would suggest there is a deficit of more than 2.7 million spay/neuter surgeries that animal welfare organizations have yet to address.

Domestic cat embryos reveal unique transcriptomes of developing incisor, canine, and premolar teeth.

Division of the dentition into morphologically distinct classes of teeth (incisors, canines, premolars, and molars) and the acquisition of tribosphenic molars facilitated precise occlusion between the teeth early in mammal evolution. Despite the evolutionary and ecological importance of distinct classes of teeth with unique cusp, crest, and basin morphologies, relatively little is known about the genetic basis for the development of different tooth classes within the embryo. Here we investigated genetic differences between developing deciduous incisor, canine, and premolar teeth in the domestic cat (Felis catus), which we propose to be a new model for tooth development. We examined differences in both developmental timing and crown morphology between the three tooth classes. Using RNA sequencing of early bell stage tooth germs, we showed that each of the three deciduous tooth classes possess a unique transcriptional profile. Three notable groups of genes emerged from our differential expression analysis; genes involved in the extracellular matrix (ECM), Wnt pathway signaling, and members of multiple homeobox gene families (Lhx, Dlx, Alx, and Nkx). Our results suggest that ECM genes may play a previously under-appreciated role in shaping the surface of the tooth crown during development. Differential regulation of these genes likely underlies differences in tooth crown shape and size, although subtle temporal differences in development between the tooth germs could also be responsible. This study provides foundational data for future experiments to examine the function of these candidate genes in tooth development to directly test their potential effects on crown morphology.

Rethinking the Animal Shelter's Role in Free-Roaming Cat Management.

Substantial societal investment is made in the management of free-roaming cats by various methods, with goals of such programs commonly including wildlife conservation, public health protection, nuisance abatement, and/or promotion of cat health and welfare. While there has been a degree of controversy over some of the tactics employed, there is widespread agreement that any method must be scientifically based and sufficiently focused, intensive and sustained in order to succeed. The vast majority of free-roaming cat management in communities takes place through local animal shelters. Throughout the 20th century and into the 21st, this consisted primarily of ad hoc admission of cats captured by members of the public, with euthanasia being the most common outcome. In North America alone, hundreds of millions of cats have been impounded and euthanized and billions of dollars invested in such programs. Given the reliance on this model to achieve important societal goals, it is surprising that there has been an almost complete lack of published research evaluating its success. Wildlife conservation and public health protection will be better served when debate about the merits and pitfalls of methods such as Trap-Neuter-Return is grounded in the context of realistically achievable alternatives. Where no perfect answer exists, an understanding of the potential strengths and shortcomings of each available strategy will support the greatest possible mitigation of harm-the best, if still imperfect, solution. Animal shelter function will also benefit by discontinuing investment in methods that are ineffective as well as potentially ethically problematic. This will allow the redirection of resources to more promising strategies for management of cats as well as investment in other important animal shelter functions. To this end, this article reviews evidence regarding the potential effectiveness of the three possible shelter-based strategies for free-roaming cat management: the traditional approach of ad hoc removal by admission to the shelter; admission to the shelter followed by sterilization and return to the location found; and leaving cats in place with or without referral to mitigation strategies or services provided by other agencies.

Feline Heartworm in Clinical Settings in a High Canine Prevalence Area.

Heartworm (HTW) infection in cats is associated with persistent pulmonary pathology, even when clinical signs are absent. Treatment options for cats are limited once infected, making prevention an important topic for discussion with cat owners. In Brazil, tests to detect feline HTW infections are unavailable, likely leading to an underestimation of its impact on the wellbeing of cats. The present study investigated the seroprevalence of HTW antigen in cats living in an area with high canine HTW prevalence and investigated risk factors and clinical signs associated with HTW disease in cats from Rio de Janeiro, Brazil. Clinical examinations were conducted, and serological evaluations performed with a point-of-care test (SNAP® Feline Triple® Test, IDEXX Laboratories, Inc.). A total of 586 cats were examined. The HTW antigen seroprevalence was 1.2%. Heartworm positive results were significantly associated with vomiting and abnormal lung sounds. Results from this study indicate that cats residing in areas of high canine HTW prevalence should have HTW disease as a differential diagnosis when presenting with compatible clinical signs. Veterinarians should prioritize client education and promote regular use of effective prophylaxis to protect feline health.

Guidance for management of free-roaming community cats: a bioeconomic analysis.

OBJECTIVES: This study used computer simulation modeling to estimate and compare costs of different free-roaming cat (FRC) management options (lethal and non-lethal removal, trap-neuter-return, combinations of these options and no action) and their ability to reduce FRC population abundance in open demographic settings. The findings provide a resource for selecting management approaches that are well matched for specific communities, goals and timelines, and they represent use of best available science to address FRC issues. METHODS: Multiple FRC management approaches were simulated at varying intensities using a stochastic individual-based model in the software package Vortex. Itemized costs were obtained from published literature and expert feedback. Metrics generated to evaluate and compare management scenarios included final population size, total cost and a cost efficiency index, which was the ratio between total cost and population size reduction. RESULTS: Simulations suggested that cost-effective reduction of FRC numbers required sufficient management intensity, regardless of management approach, and greatly improved when cat abandonment was minimized. Removal yielded the fastest initial reduction in cat abundance, but trap-neuter-return was a viable and potentially more cost-effective approach if performed at higher intensities over a sufficient duration. Of five management scenarios that reduced the final population size by approximately 45%, the three scenarios that relied exclusively on removal were considerably more expensive than the two scenarios that relied exclusively or primarily on sterilization. CONCLUSIONS AND RELEVANCE: FRCs present a challenge in many municipalities, and stakeholders representing different perspectives may promote varying and sometimes incompatible population management policies and strategies. Although scientific research is often used to identify FRC impacts, its use to identify viable, cost-effective management solutions has been inadequate. The data provided by simulating different interventions, combined with community-specific goals, priorities and ethics, provide a framework for better-informed FRC policy and management outcomes.

Animal shelter management of feline leukemia virus and feline immunodeficiency virus infections in cats.

Approximately 5% of cats in animal shelters in the United States test positive for either feline leukemia virus (FeLV) or feline immunodeficiency virus (FIV), which translates to more than 100,000 positive cats managed by shelters each year. Little is known about the current status of retroviral management in animal shelters, particularly in regions burdened by chronic pet overpopulation and high shelter admissions, such as the southern United States. The purpose of this study was to describe feline retroviral management in Florida shelters. Shelters were surveyed on practices including selection of cats for testing, diagnostic techniques, and outcome options for cats with positive test results. Responses were received from 139 of 153 animal shelters known to admit cats, including 55 municipal shelters (40%), 70 private shelters (50%), and 14 private shelters with municipal contracts (10%). A total of 115 shelters (83%) performed at least some testing, most using combination point-of-care devices for simultaneous FeLV antigen and FIV antibody screening. Of shelters that performed any testing, 56 (49%) tested all cats for FeLV and 52 (45%) tested all cats for both FeLV and FIV. The most common reason for testing was screening adoptable cats (108 shelters; 94%) and cats available for transfer to other organizations (78; 68%). Testing cats in trap-neuter-return/return-to-field programs was least common (21; 18%). Most common outcome options for positive cats included adoption (74; 64%), transfer (62; 54%), and euthanasia (49; 43%). Euthanasia following a positive test result was more common for cats with FeLV (49; 43%) than for cats with FIV (29; 25%) and was more common in municipal shelters, rural shelters, shelters taking in <500 cats a year, and shelters with overall live outcome rates for cats <70%. Although Florida shelter compliance with national guidelines for identification and management of FeLV and FIV positive cats was variable, most had live outcome options for at least some of their cats with positive test results. Increased access to training and practical programmatic tools may help more shelters implement cost-effective testing protocols, reduce risk for transmission to other cats, and support the best outcomes for this vulnerable population of cats.

Shelter Medicine Sustainability from an Academic Perspective: Challenges and Issues.

A meeting of veterinary school faculty and partners, many associated with shelter medicine, and/or community medicine programming, was convened at the 2019 Shelter Medicine Veterinary Educators Conference in Pullman, WA to discuss challenges with shelter medicine program sustainability and defining the future. The discussion was facilitated by an outside consultant and is summarized in this manuscript. The goal of the meeting was to identify challenges and issues concerning the needs and goals for shelter medicine curricula to have long-term success in academic training. Four themes were identified in the transcripts including external pressure from leadership and other stakeholders, funder expectations, time horizons, and perceptions of shelters and shelter veterinarians. Addressing these challenges will be critical to ensuring stability in academic training in shelter medicine, a critical tool for both learning outcomes for general graduates and specific for veterinarians pursuing shelter medicine as a career.

Cats Are Not Fish: A Ricker Model Fails to Account for Key Aspects of Trap-Neuter-Return Programs.

In a frequently cited 2005 paper, a Ricker model was used to assess the effectiveness of trap-neuter-return (TNR) programs for managing free-roaming domestic cat populations. The model (which was originally developed for application in the management of fisheries) used data obtained from two countywide programs, and the results indicated that any population reductions, if they existed, were at best modest. In the present study, we applied the same analysis methods to data from two long-term (i.e., >20 years) TNR programs for which significant population reductions have been documented. Our results revealed that the model cannot account for some key aspects of typical TNR programs, and the wild population swings it predicts do not correspond to the relative stability of free-roaming cat populations. A Ricker model is therefore inappropriate for use in assessing the effectiveness of TNR programs. A more recently developed, stochastic model, which accounts for the movement of cats in and out of a given area, is better suited for predicting the sterilization effort necessary to reduce free-roaming cat numbers through TNR programs.

Coping With Human-Cat Interactions Beyond the Limits of Domesticity: Moral Pluralism in the Management of Cats and Wildlife.

Although human interactions with cats are often even typically analyzed in the context of domesticity, with a focus on what sorts of interactions might make both people and cats "happy at home," a large number of cats in the world live, for one reason or another, beyond the bounds of domesticity. Human interactions with these more or less free-living cats raise deeply controversial questions about how both the cats and the people they interact with should be sensibly managed, and about the moral imperatives that ought to guide the management of their interactions through the laws and public policies regulating both human interactions with pets and with wildlife. We review the geography of human interactions with cats living beyond the bounds of domesticity. We acknowledge the contributions made to ideas about how to manage cats by the animal protection movement. We review the tensions that have emerged over time between advocates for the eradication of free-living cats, because of the impacts they have on native wildlife species, and those who have imagined alternatives to eradication, most notably one or another variant of trap-neuter-return (TNR). The conflict over how best to deal with cats living beyond the bounds of domesticity and their wildlife impacts raises the prospect of stalemate, and we canvass and critique possibilities for moving beyond that stalemate.

Measuring the Humoral Immune Response in Cats Exposed to Feline Leukaemia Virus.

Retroviruses belong to an important and diverse family of RNA viruses capable of causing neoplastic disease in their hosts. Feline leukaemia virus (FeLV) is a gammaretrovirus that infects domestic and wild cats, causing immunodeficiency, cytopenia and neoplasia in progressively infected cats. The outcome of FeLV infection is influenced by the host immune response; progressively infected cats demonstrate weaker immune responses compared to regressively infected cats. In this study, humoral immune responses were examined in 180 samples collected from 123 domestic cats that had been naturally exposed to FeLV, using a novel ELISA to measure antibodies recognizing the FeLV surface unit (SU) glycoprotein in plasma samples. A correlation was demonstrated between the strength of the humoral immune response to the SU protein and the outcome of exposure. Cats with regressive infection demonstrated higher antibody responses to the SU protein compared to cats belonging to other outcome groups, and samples from cats with regressive infection contained virus neutralising antibodies. These results demonstrate that an ELISA that assesses the humoral response to FeLV SU complements the use of viral diagnostic tests to define the outcome of exposure to FeLV. Together these tests could allow the rapid identification of regressively infected cats that are unlikely to develop FeLV-related disease.

Optimizing heartworm diagnosis in dogs using multiple test combinations.

BACKGROUND: Various heartworm (HW) diagnostic testing modalities detect products of, or reactions to, different life cycle stages of Dirofilaria immitis. Microfilariae (Mf) can be directly visualized in blood, antigen (Ag) from immature and adult heartworms may be detected on commercial assays, and antibody (Ab) tests detect the host immune response to larval stages. Ag and Mf tests are commonly used in dogs, which frequently carry adult HW infections, but Ab tests have only been validated for use in cats. In some HW-infected dogs, Ag is blocked by immune complexing leading to false-negative results. Heat-treatment (HT) to disrupt these complexes can increase the sensitivity of HW Ag tests. The aim of this study was to compare different methods for diagnosing HW infection in dogs at high risk using individual and paired diagnostic tests, including an exploration of using Ab tests designed for cats to test canine samples. METHODS: One hundred stray adult (≥ 2-year-old) dogs in Florida shelters were tested using Mf, HW Ag, and HW Ab tests (feline HW Ab tests currently not commercially validated/approved for use in dogs); two versions of each test platform were used. RESULTS: Fourteen dogs tested positive using point-of-care (POC) Ag tests; an additional 2 dogs tested positive with microtiter well assay, and an additional 12 dogs tested positive using HT Ag testing. For individual tests, Ag test sensitivity/specificity compared to HT Ag was 50-57%/100%, and Ab tests were 46-64%/82-94%. Sensitivity estimates for individual tests were higher when comparing to non-HT Ag. Pairing POC Ag tests with Mf tests improved sensitivity without loss of specificity, while pairing POC Ag and Ab tests modestly increased sensitivity at the expense of specificity. CONCLUSIONS: Screening dogs for HW infection using both POC Ag and Mf detection, which is recommended by the American Heartworm Society, improved diagnostic performance in this study compared to single Ag test use, but may have missed more than one in four infected dogs. The need to improve access to highly accurate, rapid, and inexpensive large-scale HW testing for dogs in animal shelters remains largely unmet by current testing availability. The development of practical and validated protocols that incorporate heat or chemical treatment to disrupt Ag-Ab complexes in POC testing or decreasing the cost and time required for such testing in reference laboratories might provide solutions to this unmet need. Similar studies performed in countries where the prevalence of parasites such as D. repens or A. vasorum is different to the USA could potentially yield very different positive predictive values for both HT and non-HT Ag tests.

Feline Leukemia Virus p27 Antigen Concentration and Proviral DNA Load Are Associated with Survival in Naturally Infected Cats.

Longitudinal studies of cats naturally infected with feline leukemia virus (FeLV) are important for understanding disease outcomes. Levels of p27 antigen and copy numbers of proviral DNA have been associated with FeLV-infection courses. The purpose of this prospective study was to establish cutoff values for p27 antigen concentration and proviral DNA load that distinguished high positive from low positive groups of cats and to evaluate an association with survival. At enrollment, 254 cats were tested by point-of-care and microtiter plate enzyme-linked immunosorbent assays (ELISAs) for p27 antigen and real-time polymerase chain reaction (PCR) for proviral DNA. The 127 positive cats were retested monthly for six months and monitored for survival over the four-year study. A receiver operating characteristic-based analysis of samples with concordant or discordant qualitative results for p27 antigen and proviral DNA was used to establish cutoff values, and when applied to test results at enrollment for classifying cats as high positive or low positive, a significant difference in survival was observed. High positive cats had a median survival of 1.37 years (95% CI 0.83-2.02) from time of enrollment, while most low positive cats were still alive (93.1% survival). Quantitative results for p27 antigen concentration and proviral DNA load were highly correlated with survival times in FeLV-infected cats.

Heartworm prevalence in dogs versus cats: Multiple diagnostic modalities provide new insights.

The cornerstones of diagnosis of heartworm (HW) in dogs are the detection of circulating antigen from adult female Dirofilaria immitis or the visualization of microfilariae in whole blood. These tests are less sensitive in cats because of the feline immune response leading to low numbers of adult worms, but heartworm antibody tests are also licensed for use in cats. HW antibodies in cats are detectable when there has at least been larval development in the tissues, but positive antibody tests cannot distinguish between current and previous larval infections; thus, cats with positive antibody test results are considered currently or previously infected with D. immitis. The aim of the present study was to use multiple HW diagnostic modalities to maximize detection of infection in dogs and cats at high risk of infection and to compare infection prevalence between these two hosts. Blood samples collected from 100 stray dogs and 100 stray cats at Florida animal shelters were tested for HW antigen (before and after heat treatment) and microfilariae; cats were also tested for HW antibody. Dogs were significantly (P = 0.0001) more likely to be diagnosed with adult HW infection (28 %; 95 % CI: 20.1-37.6%) when compared with cats (4 %; 95 % CI: 1.6-10.2%) on the basis of positive antigen and microfilariae test results. Cats with current or previous adult, immature adult, or larval HW infections comprised 19 % (95 % CI: 12.4%-27.9%) of the feline population, which was not significantly different (P = 0.1) from the prevalence of adult D. immitis infection in dogs. Testing unprotected cats for heartworm antibodies demonstrated a similar, high risk of infection to the matched unprotected dog population in Florida, which supports the use of HW preventives in cats in areas where HW transmission occurs.

Outcome of cats referred to a specialized adoption program for feline leukemia virus-positive cats.

OBJECTIVES: The purpose of this retrospective study was to assess outcomes of cats referred to a specialized adoption program for feline leukemia virus (FeLV)-positive cats. METHODS: Cats referred to an FeLV-specific adoption program between January 2018 and July 2019 at an animal shelter in Austin, TX, USA, were first identified based on their putative FeLV status as reported by the referring shelter, rescue group, veterinarian or individual. Each cat was re-screened for FeLV upon admission and subsequently deemed infected or uninfected. Data on cat source, admission date, outcome date, outcome type, signalment and comorbidities at the time of admission were extracted from the shelter database. Outcomes were recorded up to 15 December 2019. RESULTS: In total, 801 cats suspected to be infected with FeLV were referred to the FeLV adoption program. Of these, 149 (18.6%) were ultimately deemed uninfected, and infection was confirmed in 652 (81.4%) cats. Adoption was the most common outcome for FeLV-infected cats (n = 514 cats; 78.8%), followed by euthanasia or death in care (n = 109; 16.7%). Upper respiratory infection (URI) was the most common comorbidity in FeLV-infected cats (n = 106; 16.3%) at the time of admission, which was not significantly different than URI in the cats that were deemed not to be infected with FeLV (n = 29; 19.5%). CONCLUSIONS AND RELEVANCE: This study demonstrated high national demand for a lifesaving option for cats diagnosed with FeLV. FeLV infections could not be confirmed in approximately one in five cats referred to the FeLV adoption program, a reminder of the risk behind basing the fate of a cat on a single positive test result. The majority of cats referred to the FeLV program were adopted, demonstrating that programs centered on adopter education and post-adoption support can create lifesaving outcomes for most FeLV-infected cats, despite uncertainty regarding their long-term prognosis.

Current knowledge about the antivirals remdesivir (GS-5734) and GS-441524 as therapeutic options for coronaviruses.

Recent international epidemics of coronavirus-associated illnesses underscore the urgent medical and public health need for vaccine development and regulatory body approved therapies. In particular, the current coronavirus disease 2019 (COVID-19) pandemic has quickly intensified interest in developing treatment options to mitigate impact on human life. Remdesivir (GS-5734™) is a broad-spectrum antiviral drug that is now being tested as a potential treatment for COVID-19 in international, multi-site clinical trials. Currently available evidence about the antiviral effects of remdesivir against coronaviruses is primarily based on in vitro and in vivo studies (including some on a chemically related compound, GS-441524™), which have demonstrated largely favorable findings. As the pandemic progresses, information from human compassionate use cases will continue to accumulate before the clinical trials are concluded. It is imperative for public health practitioners and the One Health community to stay up to date on the most promising potential therapeutic options that are under investigation. Thus, the purpose of this review is to synthesize the knowledge to date about remdesivir as a therapeutic option for coronaviruses, with a special focus on information relevant to the One Health community.

Heartworm prevalence in dogs versus cats: Multiple diagnostic modalities provide new insights.

The cornerstones of diagnosis of heartworm (HW) in dogs are the detection of circulating antigen from adult female Dirofilaria immitis or the visualization of microfilariae in whole blood. These tests are less sensitive in cats because of the feline immune response leading to low numbers of adult worms, but heartworm antibody tests are also licensed for use in cats. HW antibodies in cats are detectable when there has at least been larval development in the tissues, but positive antibody tests cannot distinguish between current and previous larval infections; thus, cats with positive antibody test results are considered currently or previously infected with D. immitis. The aim of the present study was to use multiple HW diagnostic modalities to maximize detection of infection in dogs and cats at high risk of infection and to compare infection prevalence between these two hosts. Blood samples collected from 100 stray dogs and 100 stray cats at Florida animal shelters were tested for HW antigen (before and after heat treatment) and microfilariae; cats were also tested for HW antibody. Dogs were significantly (P = 0.0001) more likely to be diagnosed with adult HW infection (28 %; 95 % CI: 20.1-37.6%) when compared with cats (4 %; 95 % CI: 1.6-10.2%) on the basis of positive antigen and microfilariae test results. Cats with current or previous adult, immature adult, or larval HW infections comprised 19 % (95 % CI: 12.4%-27.9%) of the feline population, which was not significantly different (P = 0.1) from the prevalence of adult D. immitis infection in dogs. Testing unprotected cats for heartworm antibodies demonstrated a similar, high risk of infection to the matched unprotected dog population in Florida, which supports the use of HW preventives in cats in areas where HW transmission occurs.

Assessment of body weight for age determination in kittens.

OBJECTIVES: The objective of this study was to assess the utility of using body weight for age determination in kittens. METHODS: Medical records were reviewed for serial body weight measurements collected from neonatal kittens (up to 8 weeks of age) from a breeding colony of specific pathogen-free domestic shorthair cats and for single-point body weight measurements of privately owned pediatric kittens (6-20 weeks of age) presenting for elective sterilization. Body weights were compared with known dates of birth and age assessed by dental eruption in combination with developmental characteristics. RESULTS: The coefficient of determination (R2) between age and body weight in longitudinally sampled neonatal kittens was 0.88, while that for pediatric kittens sampled at a single time point was 0.54. Among neonatal kittens, predicted age based on the 1 lb (0.45 kg) of body weight gain per month of age guideline corresponded to within 1 week of actual age for 243 (98.8%), 234 (95.1%), 203 (82.5%) and 191 (77.6%) kittens at 2, 4, 6 and 8 weeks of age, respectively. Among pediatric kittens, predicted age based on this guideline corresponded to within 1 week of actual age for 24 (77.4%), 411 (67.5%), 170 (57.0%), 96 (46.6%), 23 (28.8%), 15 (27.8%), one (25%) and five (17.9%) kittens at 6, 8, 10, 12, 14, 16, 18 and 20 weeks, respectively. CONCLUSIONS AND RELEVANCE: Body weight was an effective means of predicting age in kittens through 10 weeks of age. Factors other than body weight should be considered when estimating kitten age beyond that time point.

A Long-Term Lens: Cumulative Impacts of Free-Roaming Cat Management Strategy and Intensity on Preventable Cat Mortalities.

This study used a previously developed stochastic simulation model (1) to estimate the impact of different management actions on free-roaming kitten and cat mortality over a 10-year period. These longer-term cumulative impacts have not been systematically examined to date. We examined seven management scenarios, including: (1) taking no action, (2) low-intensity removal, (3) high-intensity removal, (4) low-intensity episodic culling, (5) high-intensity episodic culling, (6) low-intensity trap-neuter-return (TNR), and (7) high-intensity TNR. For each scenario we tracked within the model the number of kittens born, the number of kittens surviving to adulthood, and the number of adults removed using lethal control over the entire 10-year simulation. We further defined all kitten deaths and lethal removal of adults as "preventable" deaths because they could potentially be reduced by certain management actions. Our simulation results suggested that the cumulative number of preventable deaths over 10 years for an initial population of 50 cats is highest for a "no-action" scenario, estimated at 1,000 deaths. It is lowest for a high-intensity TNR scenario, estimated at 32 deaths, a 31-fold difference. For all management scenarios tested, including removal and culling, the model predicted fewer preventable deaths than for a no-action scenario. For all management scenarios, the model predicted that the higher-intensity option (defined in terms of the proportion of animals sterilized or removed within a given time period) would result in fewer preventable deaths over time than the lower-intensity option. Based on these findings, we conclude that management intensity is important not only to reduce populations more quickly, but also to minimize the number of preventable deaths that occur over time. Accordingly, the lessons for the animal welfare community are both encouraging and cautionary. With sufficient intensity, management by TNR offers significant advantages in terms of combined lifesaving and population size reduction. At lower intensity levels, these advantages are greatly reduced or eliminated. We recommend that those who seek to minimize suffering and maximize lifesaving for free-roaming cats attempt to balance prospective goals (i.e., saving lives tomorrow) with proximate goals (i.e., saving lives today), and recognize that thoughtful choice of management strategies can ensure that both of these complementary goals are achieved.

Corrigendum: Decrease in Population and Increase in Welfare of Community Cats in a Twenty-Three Year Trap-Neuter-Return Program in Key Largo, FL: The ORCAT Program.

[This corrects the article DOI: 10.3389/fvets.2019.00007.].