Aging in Cats: Owner Observations and Clinical Finding in 206 Mature Cats at Enrolment to the Cat Prospective Aging and Welfare Study

Paw pressure and gait in middle-aged client-owned cats with and without naturally-occurring musculoskeletal disease

Musculoskeletal disease (MSD) is common in ageing cats, resulting in chronic pain and mobility impairment, but diagnosis can be challenging. We hypothesised that there would be differences between cats with and without MSD in paw pressure and spatiotemporal and kinetic gait metrics. A cohort of 53 cats, aged between 7 and 10 years from the North West of the United Kingdom, underwent an orthopaedic examination and walked on a pressure sensitive walkway. Thirty-one of the cats (58%) were determined to be apparently-healthy, based on a normal orthopaedic examination and having no history of MSD, whilst the remaining 22 cats (42%) had findings consistent with MSD; 13/22 cats (59%) had multiple limb involvement, 7/22 (32%) had forelimb involvement and 2/22 (9%) had hindlimb involvement. Bodyweight (P = 0.048) and body condition score (BCS; P = 0.015) were both greater in cats with MSD (mean bodyweight 5.4 ± 1.35 kg; median BCS 6, IQR 6-7.75) compared with apparently-healthy cats (mean bodyweight 4.7 ± 0.94 kg; median BCS 5, IQR 4.5-6.5). There was a relatively large intra-cat variation in spatiotemporal and kinetic gait variables (coefficient of variation >3.0%), whilst a linear mixed-effects model suggested no significant difference in spatiotemporal or kinetic gait variables between apparently-healthy cats and those with MSD. Palmar and plantar pressure asymmetry was assessed by pedobarographic statistical parametric mapping (pSPM) within each individual cat, with no significant difference (P = 0.353) between the apparently heathy cats and those with MSD as to the presence or absence of asymmetry. Given the marked intra-cat variation and the 'multi-limb' nature of MSD in this cohort, it was not possible to differentiate healthy cats from those with MSD based on spatiotemporal and kinetic gait metrics or paw pressure asymmetry. Future work should examine gait in cats with defined musculoskeletal disorders (e.g. hip dysplasia) and also to track longitudinal changes within individual cats to better establish age-related trends.

Relationship between Feline Knee Joint Osteoarthritis and Bone Mineral Density Quantified Using Computed Tomography and Computed Digital Absorptiometry

Osteoarthritis (OA), including knee joint OA, is a common chronic condition in cats. In both cats and humans, knee joint OA is characterized radiographically by the presence of osteophytes, enthesiophytes, subchondral sclerosis, and joint space narrowing. However, only in humans have these radiographic signs been reported to increase bone mineral density (BMD). Therefore, this study aims to quantify the volumetric (vBMD) and relative (rBMD) BMD measures of the feline knee joint and compare BMD measures between various severities of OA to test the hypothesized OA-BMD relationship in the knee joint in cats. The 46 feline knee joints were imaged using computed tomography (CT) and conventional radiography supported by the computed digital absorptiometry (CDA) method to obtain vBMD and rBMD, respectively. Both BMD measures were assessed in three regions of interest (ROIs): the distal femur (ROI 1), patella (ROI 2), and proximal tibia (ROI 3). In all locations, vBMD and rBMD showed moderate (ROI 2: r = 0.67, p < 0.0001) to strong (ROI 1: ρ = 0.96, p < 0.0001; ROI 3: r = 0.89, p < 0.0001) positive correlations. Due to differences (p < 0.0001) in the width of the distal femur (17.9 ± 1.21 mm), patella (8.2 ± 0.82 mm), and proximal tibia (19.3 ± 1.16 mm), the rBMD was corrected (corr rBMD) using the thickness coefficient of 0.46 ± 0.04 for ROI 2 and 1.08 ± 0.03 for ROI 3. Regardless of the quantification method used, BMD measures increased linearly from a normal knee joint to severe OA, with differences in BMD between normal and mild to severe knee joint OA. The OA-BMD relationship in the feline knee joint can be preliminarily confirmed.

Drug release profile of a novel exenatide long-term drug delivery system (OKV-119) administered to cats

Beneficial weight-loss properties of glucagon-like peptide-1 receptor agonists (GLP-1RA) in obese people, with corresponding improvements in cardiometabolic risk factors, are well established. OKV-119 is an investigational drug delivery system that is being developed for the long-term delivery of the GLP-1RA exenatide to feline patients. The purpose of this study was to evaluate the drug release characteristics of subcutaneous OKV-119 implants configured to release exenatide for 84 days. Following a 7-day acclimation period, five purpose-bred cats were implanted with OKV-119 protypes and observed for a 112-day study period. Food intake, weekly plasma exenatide concentrations and body weight were measured. Exenatide plasma concentrations were detected at the first measured timepoint (Day 7) and maintained above baseline for over 84 Days. Over the first 28 days, reduced caloric intake and a reduction in body weight were observed in four of five cats. In these cats, a body weight reduction of at least 5% was maintained throughout the 112-day study period. This study demonstrates that a single OKV-119 implant can deliver the GLP-1RA exenatide for a months long duration. Results suggest that exposure to exenatide plasma concentrations ranging from 1.5 ng/ml to 4 ng/ml are sufficient for inducing weight loss in cats.

Cognitive Changes Associated with Aging and Physical Disease in Dogs and Cats

Behavior changes may indicate primary physical disease or primary behavioral disorders in veterinary patients. It is imperative to recognize that secondary behavioral problems can develop due to medical causes. The incidence of systemic disease increases with age and behavior manifestations can be similar to those expected with cognitive dysfunction syndrome. In this article, we review basic concepts of cognition, aging, and cognitive dysfunction syndrome. Additionally, we provide information regarding factors that influence cognition, and the role medical conditions have on the behavior of aging pets.

Partial weight reduction protocols in cats lead to better weight outcomes, compared with complete protocols, in cats with obesity

Background

To date, there have been no studies comparing outcomes of cats with obesity following either complete or partial weight reduction protocols.

Methods

Fifty-eight cats participated in this non-randomized observational cohort study, including 46 (79%) and 12 (21%) that underwent complete or partial weight reduction protocols, respectively. Weight loss outcomes, body composition changes and essential nutrient intake were compared between cats in the two groups.

Results

All cats remained healthy, and those on a complete weight reduction protocol lost a median of 23% (range 10-39%) of starting body weight (SBW) over 294 days (113-967 days), whereas those undergoing partial restriction lost 25% (10-41%) over 178 days (54-512 days). Neither duration nor percentage weight loss differed between groups, but those that followed a partial weight reduction protocol lost weight at a faster rate (0.81% per week) and required fewer visits (4-19) than those that followed a complete weight reduction protocol (0.61% per week, p = 0.028; 11, 4-40 visits, p = 0.009). Further, lean tissue mass declined in cats on a complete weight reduction protocol (pre: 4.20 kg, 2.64-5.72 kg; post: 3.90 kg, 2.76-5.24 kg, p < 0.001), whereas lean tissue mass was unchanged in cats on partial weight reduction protocols (pre: 3.45 kg, 2.79-4.71 kg; post: 3.41 kg, 2.90-4.59 kg, p = 0.109). In 33 (57%) cats, median intake of selenium per day was less than NRC AI and RA recommendations, whilst intake was under FEDIAF recommendation in 42 (72%) cats. Median intake of choline per day was less than NRC MR and RA recommendations in 22 (38%) and 53 (91%) cats, respectively, whereas it was under the FEDIAF recommendation in 51 (88%) cats. In a small proportion (12-14%) of cats, phenylalanine/tyrosine and potassium were under recommendations; besides these, no other essential nutrient deficiencies were seen, and there were no differences between cats undergoing complete and partial weight reduction.

Conclusion

Partial weight reduction protocols in cats lead to quicker average weight loss, with the possibility that lean tissue loss might be minimized. Such protocols might be more suitable for older cats and those with marked obesity.

Why can't we be friends? Exploring factors associated with cat owners' perceptions of the cat-cat relationship in two-cat households

Most research examining cat behavior in multi-cat households lacks focus on one group size. This gap in knowledge reduces generalizability of research findings to specific compositions of cats in multi-cat households. Given that many cat-owning households in Canada and the US are comprised of two cats, the following study used a cross-sectional survey to explore cat owners' perceptions of the cat-cat relationship in two-cat households in Canada and the US. A total of 6,529 owners of two cats completed the online questionnaire. Descriptive statistics were used to summarize the data and a logistic regression model used to assess various explanatory variables (i.e., household, management, and cat-specific factors) associated with participants perceiving their cats' relationship as negative. The logistic regression model showed that owners of two-cat households are more likely to perceive their cats' relationship as negative if both cats are spayed females, adult or mature, have a large gap in age, not related, one or both have access to the outdoors, or show aggression toward people or other animals in the home. Having multiple litterbox and feeding areas were also associated with a more negative cat-cat relationship. Overall, the complex interplay, directionality, and temporality of these factors requires further investigation for a full understanding of how to improve the cat-cat relationship in two-cat households. More research is needed to provide evidence-based recommendations for managing and supporting a positive cat-cat relationship in the home.

Ultrasonographic monitoring of feline epaxial muscle height as part of an annual wellness examination to assess for the development of sarcopenia

OBJECTIVES

The aim of this study was to determine if epaxial muscle height (EMH) could be reliably incorporated into annual routine wellness screenings, and also determine its relationship to age, body condition score (BCS), subjective muscle assessment (SMA), breed and sex in mature cats.

METHODS

EMH was determined independently by three observers from ultrasonographic examinations - collected by an additional trained individual - of cats enrolled at the Feline Healthy Ageing Clinic, University of Liverpool, UK. Age, body weight, BCS and SMA data were also collected.

RESULTS

A total of 92 cats were included, 35 of which had repeat ultrasonographic examinations 12 months apart. Enrolled cats were a median age of 8 years and 9 months at the time of the first measurement. Variation in the quality of ultrasonographic images collected did not affect muscle depth measurements (P = 0.974). Further, there was good intra- and inter-observer repeatability for all observations (intraclass correlation range 0.97-0.99). There was a moderate positive association between EMH and body weight (r = 0.49, P <0.001) but no association with age (r = -0.05, P = 0.680). There were also positive associations in EMH among cats with different BCSs (P = 0.001) and SMAs (thoracic spine, P = 0.021; lumbar spine, P = 0.014), but breed (P = 0.429) and sex (P = 0.187) had no effect. Finally, there was no change in EMH measurements in the paired samples (P = 0.145) or correlation between percentage weight and EMH change over 12 months.

CONCLUSIONS AND RELEVANCE

The accuracy of EMH measurement using ultrasonographic imaging is good, irrespective of observer experience and provided that the ultrasonographer has some training. This suggests that ultrasonographic measurement of EMH could have a major practical impact as a non-invasive determination of muscle mass in pet cat populations. Further research is required to assess longitudinal changes in muscle mass over time in senior pet cats.

2022 AAFP/ISFM Cat Friendly Veterinary Interaction Guidelines: Approach and Handling Techniques

PRACTICAL RELEVANCE

The '2022 AAFP/ISFM Cat Friendly Veterinary Interaction Guidelines: Approach and Handling Techniques' (hereafter the 'Cat Friendly Veterinary Interaction Guidelines') support veterinary professionals with feline interactions and handling to reduce the impact of fear and other protective (negative) emotions, in so doing enhancing feline welfare and In implementing these Guidelines, team satisfaction and cat caregiver confidence in the veterinary team will increase as the result of efficient examinations, better experience, more reliable diagnostic testing and improved feline wellbeing. Veterinary professionals will learn the importance of understanding and appropriately responding to the current emotional state of the cat and tailoring each visit to the individual.

CLINICAL CHALLENGES

Cats have evolved with emotions and behaviors that are necessary for their survival as both a predator and prey species. A clinical setting and the required examinations and procedures to meet their physical health needs can result in behavioral responses to protective emotions. Cat friendly interactions require understanding, interpreting and appropriately responding to cats' emotional states and giving them a perceived sense of control while performing the required assessment.

EVIDENCE BASE

These Guidelines have been created by a Task Force of experts convened by the American Association of Feline Practitioners and the International Society of Feline Medicine, based on an extensive literature review and, where evidence is lacking, the authors' experience.

ENDORSEMENTS

These Guidelines have been endorsed by a number of groups and organizations, as detailed on page 1127 and at catvets.com/interactions and icatcare.org/cat-friendly-guidelines.

Vaccination of Immunocompromised Cats

Immunocompromise is a common condition in cats, especially due to widespread infections with immunosuppressive viruses, such as feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV), but also due to chronic non-infectious diseases, such as tumours, diabetes mellitus, and chronic kidney disease, as well as treatment with immunosuppressive drugs, such as glucocorticoids, cyclosporins, or tumour chemotherapy. In this review, the European Advisory Board on Cat Diseases (ABCD), a scientifically independent board of experts in feline medicine from eleven European countries, discusses the current knowledge and rationale for vaccination of immunocompromised cats. So far, there are few data available on vaccination of immunocompromised cats, and sometimes studies produce controversial results. Thus, this guideline summarizes the available scientific studies and fills in the gaps with expert opinion, where scientific studies are missing. Ultimately, this review aims to help veterinarians with their decision-making in how best to vaccinate immunocompromised cats.