Senior Cats Research Articles

Glycine supplementation can partially restore oxidative stress-associated glutathione deficiency in ageing cats.

Intracellular levels of glutathione, the major mammalian antioxidant, are reported to decline with age in several species. To understand whether ageing affects circulating glutathione levels in cats, blood was sampled from two age groups, < 3 years and > 9 years. Further, to determine whether dietary supplementation with glutathione precursor glycine (GLY) affects glutathione concentrations in senior cats (> 8 years), a series of free GLY inclusion level dry diets were fed. Subsequently, a 16-week GLY feeding study was conducted in senior cats (> 7 years), measuring glutathione, and markers of oxidative stress. Whole blood and erythrocyte total, oxidised and reduced glutathione levels were significantly decreased in senior cats, compared with their younger counterparts (P ≤ 0·02). The inclusion level study identified 1·5 % free GLY for the subsequent dry diet feeding study. Significant increases in erythrocyte total and reduced glutathione were observed between senior cats fed supplemented and control diets at 4 weeks (P ≤ 0·03; maximum difference of 1·23 µM). Oxidative stress markers were also significantly different between groups at 8 (P = 0·004; difference of 0·68 nG/ml in 8-hydroxy-2'-deoxyguanosine) and 12 weeks (P ≤ 0·049; maximum difference of 0·62 nG/mG Cr in F2-isoprostane PGF2α). Senior cats have lower circulating glutathione levels compared with younger cats. Feeding senior cats a complete and balanced dry diet supplemented with 1·5 % free GLY for 12 weeks elevated initial erythrocyte glutathione and altered markers of oxidative stress. Dietary supplementation with free GLY provides a potential opportunity to restore age-associated reduction in glutathione in cats.

Value of repeated health screening in 259 apparently healthy mature adult and senior cats followed for 2 years.

Although regular health screening is recommended, long-term follow-up data in healthy aged cats are lacking. Determine the most common conditions in a large group of apparently healthy older cats and which diseases are manifested within 2 years in cats confirmed to be healthy based on extensive health screening. Client-owned cats. Prospective study. Thorough history, physical examination, blood tests, and urinalysis were performed in 259 apparently healthy mature adult (7-10 years) and senior (>10 years) cats. Semi-annual follow-up examinations were performed in 201 confirmed healthy cats. At baseline, 21% of apparently healthy cats were not considered healthy but were diagnosed with International Renal Interest Society (IRIS) ≥ stage 2 chronic kidney disease (CKD; 7.7%) or hyperthyroidism (4.6%), among other disorders. Disease occurred significantly more frequently in senior cats compared with mature adult cats. In addition, 40% cats were overweight, 35% had moderate to severe dental disease, and 22% had abnormal cardiac auscultation findings. Within 2 years, 28% of mature adult and 54% of senior cats that were confirmed healthy at inclusion developed new diseases, most commonly IRIS ≥ stage 2 CKD (cumulative incidence, 13.4%), hyperthyroidism (8.5%), chronic enteropathy, hepatopathy or pancreatitis (7.5%), or neoplasia (7%). The high prevalence and 2-year incidence of physical examination abnormalities and systemic diseases in apparently healthy older cats argue for regular health screening in cats ≥7 years of age. Although more common in senior cats, occult disease also occurs in mature adult cats, and owners should be informed accordingly.

Hemangiopericytoma in a senior cat - a case report

Even though hemangiopericytoma cases are common in humans and dogs, research so far indicates that they rarely occur in cats. A 13-year-old cat was admitted to an animal hospital with a bleeding mass located close to the caudal mammary glands. No abnormalities were detected in the complete blood count or serum chemistry profile. Following the results of cytology of a fine needle aspiration sample, complete removal of the mass was performed. Hemangiopericytoma was diagnosed by pathological and immunohistochemical analyses of the mass with CD31, vimentin, desmin, SMA, GFAP, SOX-10, S100B and pan-Cytokeratin. Metastasis or recurrence was not observed in the 10-month period after surgery. Compared to previous cases of feline hemangiopericytoma, this is the first cytologically examined tumor located in the mammary gland region, and represents the fourth feline hemangiopericytoma case in the literature.

Frequency of arrhythmias detected in 9440 feline electrocardiograms by breed, age, and sex

ObjectivesThe purpose of this study was to describe the frequency of arrhythmias detected in unsedated feline patients from general practice settings. AnimalsA total 10,638 feline electrocardiograms (ECGs) were retrospectively collected of which 9440 met the inclusion criteria. MethodsRecordings were evaluated by a board-certified cardiologist. If an arrhythmia was present in the ECG tracing, the cardiologist categorized the arrhythmia using pre-established keywords. ResultsAt least one arrhythmia was observed in 249 cases (2.64%, 95% confidence interval (CI): 2.34–2.98, 249/9440), with the most common arrhythmia encountered being ventricular premature complexes (1.63%, 95% CI: 1.39%–1.91%, 154/9440). Ragdoll cats had the highest odds of arrhythmia (odds ratio (OR): 3.17, 95% CI: 1.43–6.17, P=0.036). Both geriatric (Age: 13+ years, OR: 1.70, 95% CI: 1.24–2.34, P=0.013) and senior (Age: 10–13 years, OR: 1.68, 95% CI: 1.19–2.37, P=0.003) cats had higher odds of having an arrhythmia than adult cats. The odds of male cats having an arrhythmia were slightly higher than female (OR: 1.36, 95% CI: 1.06–1.76, P=0.018). Conclusions and relevanceOf the 9440 ECGs included in this study, at least one arrhythmia was detected in 249 distinct cases. Arrhythmias were more common in older cats, male cats and the Ragdoll cat breed. While it is important to note that the presence of an arrhythmia alone does not always indicate the presence of heart disease, further research on the association between breed cardiac health is needed.

61 Life Stage Feeding: Is There Path Forward for Senior/Geriatric Nutrient recommendations?

Abstract Complete and balanced foods for “all life stages”, according to the Association of American Feed Control Officials (AAFCO), meet the needs for reproduction and growth. While these are recognized as the most nutritionally demanding stages, they are relatively short time periods in the life of a pet. Unique to companion animals, and humans, is the prolonged “senior” life stage. Although this stage is not well defined, it has become evident that energy, protein and other nutrient requirements may change with age in seniors. To establish guidelines for a lifestage, that lifestage must be defined (Table 1). Species and breed differences exist in terms of aging, in that small breed dogs have longer lifespans versus large breed dogs, and cats differ from dogs, with cats showing a definable fourth lifestage of “geriatric” that differs from a “senior” lifestage. A major challenge to defining senior or geriatric nutritional needs is the fact that animals “age” at different rates, causing senior/geriatric to be the most physiologically diverse lifestage. In nutritionally complete and balanced foods, nutrients are provided in proportion to the energy content of the diet and to the expected energy intake of the pet. Regardless of lifestage, energy requirements can differ significantly among dog breeds and among individuals. Added to this is evidence that energy requirements in dogs decrease with age, such that senior dogs need about 25% fewer calories, on average, than young adult dogs. Likewise, senior cats show a decrease in energy requirements, but geriatric cats display an increase in energy needs. Thus, even if the absolute requirement for nutrients did not change with age, the content needed on an energy basis will change. One of the challenges to establishing protein requirements for senior and geriatric pets is age-related loss of lean body mass (LBM), or sarcopenia. LBM serves as a protein reservoir and provides the amino acids used on a 24/7 basis for endogenous protein synthesis, while dietary protein maintains or restores this reservoir. It has become evident that nitrogen balance studies, long used to determine protein requirements for adults, are not sufficient in that they do not account for contributions from LBM. Maintenance of LBM may be a better assay for defining protein requirements. However, LBM is lost with age in all species studied, including humans, dogs and cats. Geriatric cats lose approximately one third of their LBM, while senior dogs lose about 10%. Loss of LBM is associated with greater morbidity and mortality, thus, preservation of LBM is an important goal. While increasing protein intake can slow the loss, and vice versa, increasing protein intake alone cannot prevent loss of LBM. Therefore, an important challenge is to determine how to measure protein requirements in aging pets.

79 Functional Amino Acids in Dogs and Cats: Implications for Overall Health

Abstract The majority of pets depend exclusively on commercial pet food supplied by their owners, who now more than ever are looking for diets supporting the health and well-being of their companion animals. Due to the diverse roles of amino acids beyond protein synthesis, their use as functional nutrients in canine and feline nutrition has gained attention. Dietary supplementation of tryptophan or tyrosine, as the precursors of serotonin and catecholamines, respectively, may reduce stress, anxiety-related and agonistic behavior in dogs. Surplus dietary arginine may also confer benefits by improving cognitive function in aging dogs likely through the enhancement of nitric oxide synthesis. In adult cats, phenylalanine has been studied for its potential effect on delaying gastric emptying and promoting satiety, which could aid in prevention of feline obesity. On the other hand, diets with greater dietary lysine:calorie may protect lean body mass of senior cats, and thus, may help combat sarcopenia. Studies investigating the functional role of amino acids in dogs and cats, however, are limited and the results are often conflicting. Additionally, data on empirical determination of amino acid requirements in adult dogs and cats are scarce, potentially preventing the dietary delivery of the ideal ratios of amino acids and subsequently the provision of specific amino acids in targeted doses above the requirement to evaluate their potential functional roles. Consequently, although the functional properties of some amino acids in dogs and cats are promising, more research focusing not only on their potential health benefits, but also on the empirical determination of amino acid requirements in dogs and cats is warranted to promote their use as functional nutrients in pet food.

Determination of age-specific reference intervals for selected serum and urinary biomarkers in elderly cats.

Annual health screening is recommended in elderly cats to allow the early detection of conditions such as chronic kidney disease (CKD) and hyperthyroidism. Nevertheless, age-specific reference intervals (RIs) for renal and thyroid parameters in this population are lacking. The aim of this study was to determine age-specific RIs for selected serum and urine biomarkers related to CKD and hyperthyroidism, namely serum creatinine (sCr), symmetric dimethylarginine (SDMA), phosphate (P), total calcium (tCa), total thyroxine (TT4), urinary protein:creatinine ratio (UPC) and urine specific gravity (USG). These RIs were established for elderly cats (aged ⩾7 years) in general, as well as for mature adult cats (aged 7-10 years) and senior cats (aged >10 years) separately. A prospective study was conducted on client-owned cats aged ⩾7 years and considered healthy by their owners. The cats were screened to rule out metabolic and systemic diseases by means of a thorough history, complete physical examination, blood examination and urinalysis. The data from 206 healthy elderly cats (134 mature adult and 72 senior cats) were included. Age-appropriate RIs were determined following the guidelines of the American Society of Veterinary Clinical Pathology and compared with existing laboratory RIs. Clinically relevant differences between the age-specific RI and the laboratory RI were found for several variables. Compared with the laboratory RI, the upper limit of the RI for cats aged ⩾7 years was lower for sCr, TT4 and P, and higher for SDMA. The lower limit of the age-appropriate RI was lower for USG. The new RI was almost identical to the existing laboratory RI for tCa and UPC. Using age-specific RIs for renal and thyroid biomarkers in mature adult and senior cats has important clinical consequences for the interpretation of health screening results in elderly cats. This confirms the need to adapt laboratory RIs to the specific animal population for which the RI will be used.

Isolated discrete upper septal thickening in a non-referral cat population of senior and young cats

Introduction/objectivesDiscrete upper septal thickening (DUST) is a phenotype of elderly people. The cardiac phenotype in senior cats has been incompletely described. We aimed to characterize the echocardiographic phenotype of senior cats, specifically to determine prevalence of DUST and hypertrophic cardiomyopathy (HCM). AnimalsOne hundred and forty-nine healthy, normotensive cats. Materials and methodsProspective cross-sectional study. Senior (≥9 years) and young (<6 years) cats were recruited from non-referral population. We defined DUST as an isolated basilar septal bulge, and HCM as left ventricular wall thickness ≥6 mm. An interventricular septum ratio (basal-to-mid septal thickness ratio) was calculated. We assessed for associations between clinical and echocardiographic variables and DUST. Data are presented as mean (±SD), median (range), or frequency (percentage). ResultsOne-hundred and two senior and 47 young cats were enrolled. Aortoseptal angle (AoSA) was steeper in senior cats (137° (±14.5) vs. 145° (±12.3) in young cats, P=0.002). Eighteen cats had DUST (18/149, 12%), fourteen senior, and four young cats (P=0.4). Cats with DUST had steeper AoSA (125° (±8.3) vs. 142° (±13.7), P<0.0001) and higher interventricular septum ratio (1.4 (1.2–2.0) vs. 1.0 (0.7–1.8)). Univariable analysis showed decreased odds of DUST with greater AoSA (OR 0.9, P<0.0001), age was not associated with DUST. Twenty-nine senior cats had HCM (28.4%). Discussion/conclusionsPrevalence of DUST was 12%. There was no association between age and DUST. Smaller/steeper AoSA was the main factor associated with DUST. There was a high prevalence of HCM in this senior population.

Effect of audible static on blood pressure measurement by Doppler ultrasonic sphygmomanometry in cats.

The aim of the present study was to determine whether the use of headphones to eliminate audible static during Doppler ultrasonic sphygmomanometry affects blood pressure (BP) measurement in conscious young adult (aged 1-6 years) and mature adult/senior (aged ⩾7 years) cats. A randomized crossover study was conducted. Healthy client-owned cats (>1 year) were enrolled. Blood pressure measurements were obtained twice, 14 days apart, with or without the use of headphones worn by a veterinarian. A fear, anxiety and stress (FAS) score (0 = relaxed; 4 = severe signs) was recorded. A linear mixed-effects model was used to compare the effect of wearing headphones on BP measurement. In total, 18 young adult and 14 mature adult and senior cats with a median age of 5 years (range 1-14 years) were enrolled. Of the cats, 47% (15/32) had an average BP measurement that was at least 10 mmHg higher when using headphones compared with when not using headphones, of which a majority (11/15, 73%) were young adult cats. The average BP measurement was not different when using headphones compared with when not using headphones (mean difference -7 mmHg; 95% confidence interval -14 to 0.6; P = 0.07). When compared within age groups, the average BP measurement taken when using headphones (125 ± 15 mmHg) was lower compared with the measurement taken when not using headphones (137 ± 17 mmHg) in young adult cats (P = 0.02). The reduction in the average BP measurement with the use of headphones suggests this method may be helpful in reducing situational hypertension, particularly in young adult cats. Our findings also highlight the importance of consistent use of headphones when comparing serial measurements in a cat.

Senior cats: nutritional adaptations and practical feeding considerations

This article outlines the nutritional goals and adaptations required by cats more than 7 years of age, including nutrient modulation. The article discusses nursing interventions to help ensure optimal dietary intake and methods to help educate pet owners on nutrition for their senior cats, including practical tips on respecting feeding behaviours for cats in this life stage. It is vital to assess each cat as an individual, applying the most suitable nutritional adaptations, whether it be for a healthy senior cat, or one for whom a clinical diet may be more appropriate.

Pathological and immunohistochemical characterization of pancreatic carcinoma in cats

The aim of this study was to characterize the pathological and immunohistochemical aspects of pancreatic carcinoma in cats, through a retrospective study. From January 2010 to December 2021, 1,908 cat necropsies were performed, in which 20 cases of exocrine pancreatic neoplasia were diagnosed (1.04%). Affected cats were mature adults and seniors, except for one 1-year-old cat. In 11 cases the neoplasm was a soft, focal nodule on the left (8/11) or right (3/11) lobe. In nine cases there were multifocal nodules throughout the pancreatic parenchyma. The size of the single masses ranged from 2 to 12 cm, and the multifocal masses from 0.5 to 2 cm. The most frequent tumour type was acinar carcinoma (11/20), followed by ductal carcinoma (8/20), undifferentiated carcinoma (1/20) and carcinosarcoma (1/20). On immunohistochemical evaluation, all the neoplasms were remarkably reactive to pancytokeratin antibody. The ductal carcinomas were strongly reactive for cytokeratins 7 and 20, which proved to be a good marker for pancreatic ductal carcinoma in cats. The main form of metastasis was abdominal carcinomatosis, with a marked invasion of blood and lymphatic vessels by neoplastic cells. Our findings reinforce the fact that pancreatic carcinoma should be rated highly in the differential diagnosis in mature adult and senior cats with abdominal masses, ascites and/or jaundice.

Frequency of histologic lesions in the kidneys of cats without kidney disease.

In humans, renal aging is associated with an increased frequency of glomerulosclerosis, interstitial fibrosis, inflammation and tubular atrophy. The purpose of this study was to describe the frequency of renal histopathologic lesions in cats without kidney disease. A cross-sectional study of archival kidney tissue from 74 cats without kidney disease (serum creatinine <1.6 mg/dl; urine specific gravity >1.035) was carried out: 0-4 years (young, n = 18); 5-9 years (mature, n = 16); 10-14 years (senior, n = 34), 15+ years (geriatric, n = 6). Glomerulosclerosis, tubular atrophy, interstitial inflammation and fibrosis, and the presence or absence of lipid in the interstitium and tubules were scored by a pathologist masked to clinical data. Statistical analyses were performed as appropriate. Geriatric cats had significantly more glomerulosclerosis than mature (P = 0.01) and young cats (P = 0.004). Senior cats had significantly more glomerulosclerosis than young cats (P = 0.006). Glomerulosclerosis was weakly positively correlated with age (r = 0.48; P <0.0001). Geriatric cats had significantly more tubular atrophy than mature (P = 0.02) and young cats (P <0.0001). Senior cats had significantly more tubular atrophy than young cats (P <0.0001). Geriatric cats had significantly more inflammation than senior cats (P = 0.02), mature cats (P = 0.01) and young cats (P <0.0001). Senior cats had significantly more inflammation than young cats (P = 0.004). Geriatric and senior cats had significantly more fibrosis than young cats (P = 0.01 and P = 0.04, respectively). Frequency of tubular lipid increased with age (young: 28%; mature: 56%; senior: 79%; geriatric: 100%) as did the frequency of interstitial lipid (young: 22%, mature: 56%, senior: 85%, geriatric: 100%). Evidence of renal aging exists in cats. These changes imply that the aging kidney may be more susceptible to injury and impaired healing.

Reintroducing a Kitten to a Resident Senior Cat

Abstract This case study describes how to reintroduce a kitten to a resident senior cat after the initial introduction did not go well. The resident cat did not accept the kitten and was spending more time outside. When she came into contact with the kitten, she would hiss and growl. A slow reintroduction was carried out which was unique to this particular set of circumstances by allowing the kitten to interact in a controlled way with the older cat whilst on a harness and lead outside. A similar method can also be used indoors with a barrier in-between the cats, tailored to suit each case, which is described under Option 2 in the ‘Courses of Action and Treatment’ section.

Renal Senescence, Telomere Shortening and Nitrosative Stress in Feline Chronic Kidney Disease.

Kidney tissues from cats with naturally occurring chronic kidney disease (CKD) and adult and senior cats without CKD were assessed to determine whether telomere shortening and nitrosative stress are associated with senescence in feline CKD. The histopathologic assessment of percent global glomerulosclerosis, inflammatory infiltrate, and fibrosis was performed. Senescence and nitrosative stress were evaluated utilizing p16 and iNOS immunohistochemistry, respectively. Renal telomere length was evaluated using telomere fluorescent in situ hybridization combined with immunohistochemistry. CKD cats were found to have significantly increased p16 staining in both the renal cortex and corticomedullary junction compared to adult and senior cats. Senior cats had significantly increased p16 staining in the corticomedullary junction compared to adult cats. p16 staining in both the renal cortex and corticomedullary junction were found to be significantly correlated with percent global glomerulosclerosis, cortical inflammatory infiltrate, and fibrosis scores. p16 staining also correlated with age in non-CKD cats. Average telomere length was significantly decreased in CKD cats compared to adult and senior cats. CKD cats had significantly increased iNOS staining compared to adult cats. Our results demonstrate increased renal senescence, telomere shortening, and nitrosative stress in feline CKD, identifying these patients as potential candidates for senolytic therapy with translational potential.

The efficacy of pinch-induced behavioral inhibition (clip restraint) in domestic cats (Felis catus) declines with age

Domestic cats often need to be restrained for clinical procedures. One method that is commonly used to restrain cats is manual scruffing or pinch-induced behavioral inhibition (PIBI; i.e., clip restraint). However, few studies have evaluated its efficacy in cats. This study aims to evaluate the efficacy of PIBI in cats and determine if it declines with age. A total of 142 cats (72 females and 70 males) were used for this study. For the purpose of this study, the age groups were defined as kittens (0-0.5 years of age; n = 14), junior (0.5-2 years; n = 27), adult (2-6 years; n = 43), mature (6-10 years; n = 32), and senior (10-14 years; n = 26) cats. Cats were taken individually into a familiar room, placed on table, and 3 clothes pegs were put on their scruff. The cats were then released and the PIBI response graded as (1) no response, (2) weak, (3) moderate, (4) strong, or (5) very strong. Grades 3-5 were considered as effective restraint, defined as restraint without the need additional handling. Of the 142 cats, 95 (66.9%) were effectively restrained by PIBI and only one cat exhibited an overt negative response (vocalized and aggressively tried to remove the clips). However, the percentage of cats for which PIBI restraint was effective declined with age (P < 0.001): 100.0% of kittens, 74.1% of junior cats, 69.8% of adult cats, 53.1% of mature cats, and 53.8% of senior cats. The decrease in the efficacy of clip restraint with age was more pronounced in male cats than female cats. Neuter status did not significantly affect the probability of PIBI being effective for both male and female cats. The mean PIBI response grade declined with age, with the mean response being stronger in kittens (4.64 ± 0.20) than in cats older than 1 year of age (3.05 ± 0.12; P < 0.001). There was no difference in the graded response among junior, adult, mature and senior cats. Neuter status (entire vs. neutered) did not affect the PIBI response grade in female cats (3.37 ± 0.18 and 3.06 ± 0.33, respectively; P = 0.41), but the response was stronger in entire toms (3.84 ± 0.34) than neutered males (2.82 ± 0.19; P = 0.01). This was likely related to age as 15 of the 19 entire toms were less than 2.0 years old. In summary, PIBI provided effective restraint for 66.9% of the cats, but the efficacy of PIBI and response grade declined with age, with the biggest decline seen between kittens and junior cats.

Effect of Nutrition on Age-Related Metabolic Markers and the Gut Microbiota in Cats.

Age-related changes in the gut microbiota and metabolites are associated with the increased risk of detrimental conditions also seen with age. This study evaluated whether a test food with potential anti-aging benefits results in favorable changes in plasma and fecal metabolites and the fecal microbiota in senior cats. Forty healthy domestic cats aged 8.3–13.5 years were fed a washout food for 30 days, then control or test food for 30 days. After another 30-day washout, cats were switched to the other study food for 30 days. Assessment of plasma and fecal metabolites showed lower levels of metabolites associated with detrimental processes (e.g., uremic toxins) and higher levels of metabolites associated with beneficial processes (e.g., tocopherols) after cats consumed the test food compared with the control food. A shift toward proteolysis with the control food is supported by higher levels of amino acid metabolites and lower levels of carbohydrate metabolites. Operational taxonomic units of greater abundance with the test food positively correlated with carbohydrate and nicotinic acid metabolites, and negatively correlated with uremic toxins, amino acid metabolism, secondary bile salts, and branched-chain fatty acids. Taken together, the test food appears to result in greater levels of metabolites and microbiota associated with a healthier state.

Feline comorbidities: The intermingled relationship between chronic kidney disease and hypertension.

Chronic kidney disease (CKD) is a highly prevalent disorder of senior cats. CKD is frequently diagnosed in association with hypertension, and the two conditions have an intermingled cause-and-effect relationship. Hypertensive target organ damage (TOD) to the eye, brain, heart and kidney significantly impacts the welfare of cats suffering from this comorbidity. Hypertension also drives proteinuria, which is an independent risk factor for progression and mortality in cats with CKD. Blood pressure monitoring and institution of effective antihypertensive treatment, where indicated, is therefore crucial in effective management of the feline CKD patient. Current guidelines recommend a target systolic blood pressure of <160 mmHg to minimise risk of TOD. Both amlodipine besylate and telmisartan are effective antihypertensive agents for use in these patients. Clinical signs of hypertension may not be apparent to owners of affected cats until severe hypertensive TOD is present. Despite this, blood pressure monitoring in cats with CKD is still infrequently performed, and hypertension likely remains underdiagnosed in this population. This review is based upon evaluation of the currently available published literature, including relevant consensus statements. There is a large body of evidence supporting the association between hypertension and CKD in cats. However, significant aspects, such as the mechanisms behind this association, and effect of hypertension and antihypertensive treatment on mortality and progression of CKD, remain unclear. Further research is therefore required in order to improve understanding of these conditions.

Healthy Ageing Is Associated with Preserved or Enhanced Nutrient and Mineral Apparent Digestibility in Dogs and Cats Fed Commercially Relevant Extruded Diets.

Simple SummaryPreventative healthcare and provision of optimal nutrition from early ages is increasing the life expectancy of companion animals today. However, as part of the normal ageing process, changes in the capacity to digest and use dietary nutrients may occur, which could contribute to deficiency in energy and/or essential nutrients. Based on previous studies, an effect of ageing on nutrient digestibility has primarily been observed when feeding low-fat or high-fibre diets. In this study, we evaluated the effect of age on nutrient digestibility using healthy dogs and cats up to 14 years old by feeding diets differing in fat and fibre contents. Older dogs and cats had a preserved nutrient digestibility, in some cases showed an enhanced digestibility of fibre and calcium. Interestingly, older cats had a lower nutrient digestibility with one of the diets, which was unrelated to fat and fibre levels, but was possibly associated with other ingredients in the formulation. Our findings support the use of a wide range of fat and fibre levels in healthy older dogs and cats within the studied ages. However, ingredient sources should be considered in the formulation of senior diets.Age-related changes in gastrointestinal function have been reported in companion animals, but the impact on digestive efficiency remains uncertain. Healthy dogs (n = 37; 2.6–14.2 years) received four diets varying in total dietary fibre (TDF; 6–29%, as fed). Healthy cats (n = 28; 1–13 years) received four diets with two fat (10–12%; 17–18%) and TDF (9 and 12%) levels. In a crossover design, diets were provided over four consecutive 10-day cycles, including a 4-day faecal collection. Apparent crude protein (CP), ether extract (EE), TDF, calcium (Ca), and phosphorus (P) digestibilities were determined. The effect of age was analysed as a continuous variable in dogs and as differences between adult (1–5 years) and senior (7–13 years) cats. In dogs, EE digestibility was unaffected by age (p > 0.10). Dogs of 6–12 years had higher digestibility of CP (p = 0.032), TDF (p = 0.019), Ca (p = 0.019), and P (p = 0.024) when fed the 6% TDF diet. Senior cats had greater digestibility of TDF (p < 0.01) and Ca (p = 0.024) but had lower EE and CP digestibility with one diet (17% fat; 9%TDF) (age, p > 0.10; diet × age, p < 0.001). Healthy ageing was associated with preserved nutrient digestibility in dogs and cats within the age ranges studied. The effect of ingredient sources in senior cats warrants further investigation.

Evaluation of iron, copper and zinc concentrations in commercial foods formulated for healthy cats.

The aim of this study was to analyze iron, copper and zinc concentrations in commercial foods and compare among food formats (dry, canned, raw), foods marketed by age category (adult 1+ years and senior 7+ years) and foods intended for adult maintenance vs all life stages. In total, 112 commercial non-therapeutic food products marketed for healthy adult and senior cats were purchased in the USA. Foods were analyzed for their proximate composition. Trace mineral concentrations were measured using inductively coupled argon plasma-optical emission spectroscopy and described on a calculated metabolizable energy basis using standard modified Atwater values. Measured iron (median 58.4 mg/1000 kcal [range 15.7-379.0]), copper (median 5.6 mg/1000 kcal [range 0.8-13.3]) and zinc (median 47.6 mg/1000 kcal [range 7.6-128.1]) concentrations were highly variable among cat foods. When all food products - regardless of their nutritional adequacy substantiation method - were compared with the Association of American Feed Control Officials regulatory minimums, 13/112 food products had a mineral deficiency, of which a majority (n = 11/13) were raw food products. Raw foods had significantly lower trace mineral concentrations compared with dry food products and, except for copper, canned food products. Cat foods marketed for senior cats had higher iron (P = 0.019) and zinc (P <0.0001) concentrations than foods marketed for adult cats. Foods intended for adult maintenance had higher iron (P = 0.003) and zinc concentrations than foods intended for all life stages (P <0.0001). Iron, copper and zinc concentrations in commercial non-therapeutic foods for adult and senior cats are highly variable. A minority of foods - mainly raw food products - were deficient in these minerals. It is unknown if some foods with high trace mineral concentrations could have adverse effects as studies are needed to establish safe upper limits for dietary intake of trace minerals in healthy cats.

2021 AAFP Feline Senior Care Guidelines.

The '2021 AAFP Feline Senior Care Guidelines' are authored by a Task Force of experts in feline clinical medicine and serve as an update and extension of those published in 2009. They emphasize the individual patient evaluation and the process of aging, with references to other feline practice guidelines for a more complete discussion of specific diseases. Focusing on each cat encourages and empowers the owner to become a part of the cat's care every step of the way. A comprehensive discussion during the physical examination and history taking allows for tailoring the approach to both the cat and the family involved in the care. Videos and analysis of serial historical measurements are brought into the assessment of each patient. These Guidelines introduce the emerging concept of frailty, with a description and methods of its incorporation into the senior cat assessment. Minimum database diagnostics are discussed, along with recommendations for additional investigative considerations. For example, blood pressure assessment is included as a minimum diagnostic procedure in both apparently healthy and ill cats. Cats age at a much faster rate than humans, so practical timelines for testing frequency are included and suggest an increased frequency of diagnostics with advancing age. The importance of nutrition, as well as senior cat nutritional needs and deficiencies, is considered. Pain is highlighted as its own syndrome, with an emphasis on consideration in every senior cat. The Task Force discusses anesthesia, along with strategies to allow aging cats to be safely anesthetized well into their senior years. The medical concept of quality of life is addressed with the latest information available in veterinary medicine. This includes end of life considerations like palliative and hospice care, as well as recommendations on the establishment of 'budgets of care', which greatly influence what can be done for the individual cat. Acknowledgement is given that each cat owner will be different in this regard; and establishing what is reasonable and practical for the individual owner is important. A discussion on euthanasia offers some recommendations to help the owner make a decision that reflects the best interests of the individual cat.