The guidelines, authored by a Task Force of experts in feline clinical medicine, are an update and extension of the AAFP–AAHA Feline Life Stage Guidelines published in 2010. The guidelines are published simultaneously in the Journal of Feline Medicine and Surgery (volume 23, issue 3, pages 211–233, DOI: 10.1177/1098612X21993657) and the Journal of the American Animal Hospital Association (volume 57, issue 2, pages 51–72, DOI: 10.5326/JAAHA-MS-7189). A noteworthy change from the earlier guidelines is the division of the cat’s lifespan into a five-stage grouping with four distinct age-related stages (kitten, young adult, mature adult, and senior) as well as an end-of-life stage, instead of the previous six. This simplified grouping is consistent with how pet owners generally perceive their cat’s maturation and aging process, and provides a readily understood basis for an evolving, individualized, lifelong feline healthcare strategy. The guidelines include a comprehensive table on the components of a feline wellness visit that provides a framework for systematically implementing an individualized life stage approach to feline healthcare. Included are recommendations for managing the most critical health-related factors in relation to a cat’s life stage. These recommendations are further explained in the following categories: behavior and environmental needs; elimination; life stage nutrition and weight management; oral health; parasite control; vaccination; zoonoses and human safety; and recommended diagnostics based on life stage. A discussion on overcoming barriers to veterinary visits by cat owners offers practical advice on one of the most challenging aspects of delivering regular feline healthcare.

Background Intestinal dysbiosis has been documented in humans with chronic kidney disease (CKD) and is thought to contribute to production of the uremic toxins indoxyl sulfate (IS) and p‐cresol sulfate (pCS). Characteristics of the fecal microbiome in cats with CKD and correlation to serum concentrations of uremic toxins are unknown. Objectives To characterize the fecal microbiome and measure serum IS and pCS concentrations of cats with CKD in comparison to healthy older cats. Animals Thirty client‐owned cats with CKD (International Renal Interest Society stages 2‐4) and 11 older (≥8 years) healthy control cats. Methods Prospective, cross‐sectional study. Fecal samples were analyzed by sequencing of 16S rRNA genes and Escherichia coli quantitative PCR (qPCR). Serum concentrations of IS and pCS measured using liquid chromatography tandem mass spectrometry. Results Cats with CKD had significantly decreased fecal bacterial diversity and richness. Escherichia coli qPCR showed no significant difference in bacteria count between control and CKD cats. Cats with stage 2 (P = .01) and stages 3 and 4 (P = .0006) CKD had significantly higher serum IS concentrations compared to control cats. No significant difference found between stage 2 and stages 3 and 4 CKD. The pCS concentrations were not significantly different between CKD cats and control cats. Conclusions and Clinical Importance Decreased fecal microbiome diversity and richness is associated with CKD in cats. Indoxyl sulfate concentration is significantly increased with CKD, and cats with stage 2 CKD may suffer from a similar uremic toxin burden as do cats with later stage disease.

Practical relevance: Stem cell therapy is an innovative field of scientific investigation with tremendous potential for clinical application in veterinary medicine. Based on the known desirable immunomodulatory properties of mesenchymal stem cells, this therapy holds promise for the treatment of a variety of inflammatory diseases in cats. Aims: This review details our current understanding of feline stem cell biology and proposed mechanism of action. Studies performed in feline clinical trials for diseases including gingivostomatitis, chronic enteropathy, asthma and kidney disease are summarized, with the goal of providing an overview of the current status of this treatment modality and its potential for the future.

Background Straight‐ and branched‐chain (BCFA) short‐chain fatty acids (SCFAs) are produced by colonic microbiota and have both beneficial and deleterious effects in humans with chronic kidney disease (CKD). Fecal SCFAs in cats with CKD have not been described. Objective To characterize fecal SCFA concentrations in cats with CKD as compared to healthy geriatric cats and correlate SCFA to serum indoxyl sulfate (IS) and p‐cresol sulfate (pCS) concentrations. Animals Twenty‐eight cats with CKD (International Renal Interest Society [IRIS] stages 2, 3, and 4) and 11 older (≥ 8 years) healthy geriatric cats. Methods Prospective, cross‐sectional study. Voided feces were analyzed using stable isotope dilution gas chromatography‐mass spectrometry to determine fecal concentrations of SCFAs. Serum concentrations of IS and pCS were measured using liquid chromatography tandem mass spectrometry. Results Fecal isovaleric acid concentrations were significantly higher in CKD cats(P = .02) Cats with IRIS CKD stage 3 and 4 had significantly higher fecal isovaleric acid concentrations compared to healthy geriatric cats (P = .03), but not compared to IRIS CKD stage 2 cats. Total fecal concentrations of BCFAs were found to correlate weakly with serum creatinine concentration (rho, 0.33; P = .05), blood urea nitrogen concentration (rho, 0.40; P = .01), and pCS concentration (rho, 0.35; P = .04). Conclusions and Clinical Importance Fecal isovaleric acid concentrations were higher in CKD cats, particularly in late stage disease, compared to healthy geriatric cats. Fecal BCFA concentrations correlated with pCS and were higher in cats with muscle wasting, providing evidence for malassimilation of protein in CKD cats.

Objectives: The purpose of this study was to assess serum concentrations of gabapentin in cats with chronic kidney disease (CKD) vs clinically healthy cats. Methods: Five healthy cats were enrolled in a pharmacokinetic study. A single 20 mg/kg dose of gabapentin was administered orally and blood was obtained at 0, 0.25, 0.5, 1, 1.5, 2, 3, 4, 8, 12, 24 and 36 h via a jugular catheter. Serum gabapentin concentrations were measured using liquid chromatography coupled to tandem mass spectrometry. Non-compartmental pharmacokinetic analysis was performed. The same five healthy cats plus 25 cats with stable International Renal Interest Society stage 2 (n = 14) and 3 (n = 11) CKD were enrolled in a limited sampling study. Cats in both groups received a single 10 mg/kg dose of gabapentin, and serum gabapentin concentrations and compliance scores were obtained 3 and 8 h post-administration. Results: Cats with CKD had significantly higher dose-normalized serum gabapentin concentrations than normal cats at 3 h ( P = 0.0012 CKD vs normal 10 mg/kg; P = 0.008 CKD vs normal 20 mg/kg) and 8 h ( P <0.0001 CKD vs normal 10 mg/kg; P <0.0001 CKD vs normal 20 mg/kg). Both 3 and 8 h dose-normalized serum gabapentin concentrations were significantly correlated with serum creatinine (3 h: P = 0.03, r = 0.39; 8 h: P = 0.001, r = 0.57) and symmetric dimethylarginine (3 h: P = 0.03, r = 0.41; 8 h: P = 0.007, r = 0.48). There was a significant correlation between 3 h serum gabapentin concentrations and compliance scores ( P = 0.0002, r = 0.68). Conclusions and relevance: Cats with CKD that received 10 mg/kg of gabapentin had significantly higher dose-normalized serum concentrations than normal cats that received 20 mg/kg, supporting the need to dose-reduce in this patient population.

Foamy viruses (FVs) are globally prevalent retroviruses that establish apparently apathogenic lifelong infections. Feline FV (FFV) has been isolated from domestic cats with concurrent diseases, including urinary syndromes. We experimentally infected five cats with FFV to study viral kinetics and tropism, peripheral blood mononuclear cell (PBMC) phenotype, urinary parameters, and histopathology. A persistent infection of primarily lymphoid tropism was detected with no evidence of immunological or hematologic perturbations. One cat with a significant negative correlation between lymphocytes and PBMC proviral load displayed an expanded FFV tissue tropism. Significantly increased blood urea nitrogen and ultrastructural kidney changes were noted in all experimentally infected cats, though chemistry parameters were not outside of normal ranges. Histopathological changes were observed in the brain, large intestine, and other tissues. In order to determine if there is an association of FFV with Chronic Kidney Disease, we additionally screened 125 Australian pet cats with and without CKD for FFV infection and found that FFV is highly prevalent in older cats, particularly in males with CKD, though this difference was not statistically significant compared to controls. Acute FFV infection was clinically silent, and while some measures indicated mild changes, there was no overt association of FFV infection with renal disease.