Evidence for seasonal reproduction in UK domestic cats

Cat: Empirical modelling of Felis catus population dynamics in the UK

Domestic cats are popular companion animals, however not all live in human homes and many cats live within shelters or as free-roaming, unowned- feral or stray cats. Cats can transition between these subpopulations, but the influence of this connectivity on overall population dynamics, and the effectiveness of management interventions, remain poorly understood. We developed a UK-focused multistate Matrix Population Model (MPM), combining multiple life history parameters into an integrated model of cat demography and population dynamics. The model characterises cats according to their age, subpopulation and reproductive status, resulting in a 28-state model. We account for density-dependence, seasonality and uncertainty in our modelled projections. Through simulations, we examine the model by testing the effect of different female owned-cat neutering scenarios over a 10-year projection timespan. We also use the model to identify the vital rates to which total population growth is most sensitive. The current model framework demonstrates that increased prevalence of neutering within the owned cat subpopulation influences the population dynamics of all subpopulations. Further simulations find that neutering owned cats younger is sufficient to reduce overall population growth rate, regardless of the overall neutering prevalence. Population growth rate is most influenced by owned cat survival and fecundity. Owned cats, which made up the majority of our modelled population, have the most influence on overall population dynamics, followed by stray, feral and then shelter cats. Due to the importance of owned-cat parameters within the current model framework, we find cat population dynamics are most sensitive to shifts in owned cat husbandry. Our results provide a first evaluation of the demography of the domestic cat population in the UK and provide the first structured population model of its kind, thus contributing to a wider understanding of the importance of modelling connectivity between subpopulations. Through example scenarios we highlight the importance of studying domestic cat populations in their entirety to better understand factors influencing their dynamics and to guide management planning. The model provides a theoretical framework for further development, tailoring to specific geographies and experimental investigation of management interventions.

Reproduction of Domestic Cats in Laboratories, Catteries, and Feral Colonies: A Review

Cat reproduction is important for research and commercial cat breeding operations, as well as the control of feral cat populations. This review describes studies examining reproductive performance in laboratory cats, privately-owned breeding cats, and feral cats, including sexual maturity, the estrous cycle (timing, behavior, and hormonal changes), seasonal effects, gestation length, parturition (litter size, litter weight, and parity effects), mortality, and stillbirth. Because the studies highlighted in this review vary in the location where they were conducted and the region's management practices, these factors should be considered depending on the goal of the reader when interpreting these data. Furthermore, standard practices were lacking in some earlier studies of cat reproduction, so they should be considered for historical context only and may not reflect the actual reproductive potential of cats as described in the new studies due to advancements in husbandry practices and nutrition. The objective of this manuscript is to review scientific studies examining reproductive performance in laboratory cats, privately-owned breeding cats, and feral cats. The data sources for this manuscript included original research publications and scientific reviews from the veterinary literature. All reviews or studies that augmented the knowledge of the reproduction of domestic cats in laboratories, catteries, and feral colonies were included. Most studies on laboratory cats have been conducted under the conditions of controlled light cycles, temperature, and diet. The environmental effects on reproductive behavior are subtler than those in feral cat studies, but the effects are still distinguishable. Cat breeding studies focus on genetic effects and rely heavily on surveys or questionnaires from cat breeders. However, the reliability of these data can be variable, in part because the methodology of record-keeping and other protocols are generally not reported. In addition, laboratory animal management standards, specific pathogen-free cat colonies, and nutritional requirements for cats were not fully established until the 1970s. Reproductive outcomes of earlier studies may not be a true representation of the modern cat due to more advanced, regulated husbandry practices, including improvements in nutrition, resulting in diets formulated to meet feline requirements for every life stage.

Radiographic lumbosacral vertebral abnormalities and constipation in cats

Background and Aim:

Lumbosacral intervertebral disk disease (IVDD) in cats usually develops concurrent with constipation, spondylosis deformans, and sacralization. However, the prevalence of lumbar IVDD in cats was considered low, and there was less information on the incidence of non-traumatic lumbosacral vertebral abnormalities that may affect large bowel dysfunction. This study aimed to retrospectively investigate the relationship between non-traumatic lumbosacral vertebral abnormalities, both congenital and acquired, and large bowel dysfunction in cats.

Materials and Methods:

Of 3108 cats that were presented to the Diagnostic Imaging Unit, the Small Animal Teaching Hospital, Faculty of Veterinary Science, Chulalongkorn University, between March 2016 and February 2018, 1365 cats met the inclusion criteria. All abdominal radiographs were reviewed, and all subsequent data were recorded, including the presence of congenital or acquired lumbosacral lesions, number of lumbar vertebrae, and length of the second, fifth, and last lumbar vertebrae, including the type of lumbar abnormalities. Moreover, radiographic information relating to constipation and megacolon was also collected.

Results:

Non-traumatic lumbosacral vertebral abnormalities were observed in 29.74% of cats. The most common congenital lumbosacral vertebral abnormalities were six lumbar vertebrae, sacralization, and lumbarization, whereas most common acquired lumbosacral abnormalities were bone spur, narrowing disk space, spondylosis deformans, and lumbosacral degeneration, respectively. Cats with abnormal lumbosacral vertebrae are prone to have more problems with the large bowel (p=0.0057; odds ratio=1.731). Moreover, congenital and acquired lumbosacral abnormalities were also at risk of large bowel abnormalities (p=0.0069; odds ratio=1.920 and p<0.0001; odds ratio=4.107, respectively).

Conclusion:

This study revealed the evidence and distribution of the variation in feline lumbar anatomy and also elucidated that cats with abnormal lumbar vertebral columns were more likely to have problems with distal gastrointestinal tracts than those without.

A shift towards early-age desexing of cats under veterinary care in Australia

The global problem of unowned domestic cats, driven by their phenomenal reproductive success, carries significant economic, animal welfare and biodiversity costs. Desexing owned cats prior to puberty prevents unwanted litters that contribute to unowned cat populations. The prevalence and predictors of desexing, and the age at which surgery was carried out were investigated using anonymized electronic patient records in the VetCompass Australia database of cats presented to veterinary practices. Of 52,941 cats born between 2010 and 2017, 83.6% were desexed. Among 7463 desexed females, 21.5% had been desexed by 4 months of age, 59.8% by 6 months and 85.4% by 1 year. Sex, breed, location and socioeconomic indices significantly influenced desexing status and age at surgery. Cats born between 2010 and 2017 had greater odds of being desexed than cats born between 1995and 2009 at each age cut-off (≤ 4 months [OR 1.76, CI₉₅ 1.58-1.97], ≤ 6 months [OR 1.50, CI₉₅ 1.38-1.62] and ≤ 1 year [OR 2.33, CI₉₅ 2.11-2.57] p < 0.001). Most cats presented to veterinarians in Australia are desexed. Compared with cats born before 2010, cats born later are significantly younger at desexing but, even so, many cats would have reached sexual maturity before surgery. These findings will inform the design of front-line strategies promoting prepubertal desexing and they demonstrate, for the first time, a shift towards desexing younger cats.

The History of Farm Foxes Undermines the Animal Domestication Syndrome

The Russian Farm-Fox Experiment is the best known experimental study in animal domestication. By subjecting a population of foxes to selection for tameness alone, Dimitry Belyaev generated foxes that possessed a suite of characteristics that mimicked those found across domesticated species. This 'domestication syndrome' has been a central focus of research into the biological pathways modified during domestication. Here, we chart the origins of Belyaev's foxes in eastern Canada and critically assess the appearance of domestication syndrome traits across animal domesticates. Our results suggest that both the conclusions of the Farm-Fox Experiment and the ubiquity of domestication syndrome have been overstated. To understand the process of domestication requires a more comprehensive approach focused on essential adaptations to human-modified environments.

Attitudes and Practices of Australian Veterinary Professionals and Students towards Early Age Desexing of Cats

Simple Summary

Globally, desexing is used to reduce/prevent overpopulation of cats. However, its effective use is hampered by widely held views that it should occur at around six months of age, whereas female cats can breed from four months of age. As a result, many cats may have an unplanned litter before they are desexed. In Australia, increasing numbers of municipalities are mandating desexing of cats by three months of age, before the traditional age of 4–6 months. Achieving this goal requires support from veterinary professionals, so we used online and face-to-face surveys to determine the preferred desexing ages for cats and rationale of 957 Australian veterinarians, veterinary nurses, veterinary science students, and veterinary nursing students. A complementary survey of 299 veterinary practice websites across Australia documented information provided about desexing cats. Vet nurses and nursing students were more conservative than vets or vet students, preferring to desex cats (especially females) after four months because of concerns about anaesthetic risk. Over half of surveyed websites provided no information about desexing cats or offered desexing without explaining why it was necessary or when to perform it. In Australia, the preferences and practices of some current/future veterinary professionals do not match changing cat legislation.

Abstract

Surgical desexing of cats is typically carried out after six months of age (Mature Age Desexing, MAD); between 4–6 months (Traditional Age Desexing, TAD); or before four months (Early Age Desexing, EAD). We complemented existing surveys of veterinarians’ acceptance of EAD with online and face-to-face surveys, to ascertain the preferred desexing ages for cats and rationale of 957 Australian veterinarians, veterinary nurses, veterinary science students, and veterinary nursing students. A complementary survey of 299 veterinary practice websites across Australia documented any information provided about desexing cats. The most common reason for preferred desexing ages was reducing stray cat populations (30%); 78% of these respondents chose ages aligning with EAD. Vet nurses and nursing students were more conservative than vets or vet students, preferring to desex cats >4 months. Perceived anaesthetic risk was a major motivation, especially for nurses ≤5 years’ experience. Across 299 urban practices in Australian capital cities, 55% of surveyed websites provided no information about desexing cats or listed desexing without explaining why it was necessary, or when to perform it. Increasingly, Australian legislatures mandate desexing of cats by three months of age, so the practices of some current/future veterinary professionals do not match changing legislation.

Using Free Adoptions to Reduce Crowding and Euthanasia at Cat Shelters: An Australian Case Study

Simple Summary

Waiving adoption fees to encourage adoptions and reduce euthanasias of healthy adult cats in crowded shelters is controversial because of concerns that people attracted to free adoptions may be less responsible owners. An extremely busy kitten season in 2015 left no shelter or foster vacancies for incoming cats at Western Australia’s largest cat shelter. Instead of euthanasing healthy cats, the shelter held a three day adoption-drive where cats ≥1 year were free. Public response to the event was extremely high (weekly adoptions increased >5-fold). Post-adoption surveys were carried out and results compared with surveys of cat adopters who paid normal-fees during non-promotional periods. No differences were found between free and normal-fee adopter demographics, cat demographics, cat fate post-adoption, incidence of medical and behavioural issues, and likelihood of attaching collars, registering with local councils or allowing cats to roam freely. Mixed-media promotion of the adoption-drive attracted more first-time adopters compared with normal-fee adopters. Overall, we found no evidence for adverse outcomes associated with free adoptions. Animal shelters should not be dissuaded from occasional free adoption-drives during overflow periods.

Abstract

Many healthy adult cats are euthanised annually in shelters, and novel approaches are required to reduce euthanasia rates. Waiving adoption fees is one such approach. However, concerns that less responsible owners will be attracted to free events persist among welfare groups. We evaluated evidence for differences in cat fate, health, and adherence to husbandry legislation via a case-study of a free adoption-drive for cats ≥1 year at a Western Australian shelter. Post-adoption outcomes were compared between free adopters and a control group of normal-fee adopters. The free adoption-drive rehomed 137 cats, increasing average weekly adoptions by 533%. First-time adopters were a significantly larger portion of the free cohort, as a result of mixed-media promotions. Both adopter groups selected cats of similar age; sex and pelage. Post-adoption, both groups retained >90% cats, reporting near identical incidences of medical and behavioural problems. Adopters did not differ in legislative compliance regarding fitting collars, registering cats, or allowing cats to roam. The shelter reported satisfaction with the adoption-drive, because in addition to relieving crowding of healthy adults, adoption of full-fee kittens increased 381%. Overall, we found no evidence for adverse outcomes associated with free adoptions. Shelters should not be dissuaded from occasional free adoption-drives during overflow periods.