Cats Of Ages Research Articles

Survival time and effect of selected predictor variables on survival in owned pet cats seropositive for feline immunodeficiency and leukemia virus attending a referral clinic in northern Italy

Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) are among the most important feline infectious diseases worldwide.This retrospective study investigated survival times and effects of selected predictor factors on survival time in a population of owned pet cats in Northern Italy testing positive for the presence of FIV antibodies and FeLV antigen.One hundred and three retrovirus-seropositive cats, 53 FIV-seropositive cats, 40 FeLV-seropositive cats, and 10 FIV+FeLV-seropositive cats were included in the study. A population of 103 retrovirus-seronegative age and sex-matched cats was selected. Survival time was calculated and compared between retrovirus-seronegative, FIV, FeLV and FIV+FeLV-seropositive cats using Kaplan-Meier survival analysis. Cox proportional-hazards regression analysis was used to study the effect of selected predictor factors (male gender, peripheral blood cytopenia as reduced red blood cells − RBC- count, leukopenia, neutropenia and lymphopenia, hypercreatininemia and reduced albumin to globulin ratio) on survival time in retrovirus-seropositive populations.Median survival times for seronegative cats, FIV, FeLV and FIV+FeLV-seropositive cats were 3960, 2040, 714 and 77days, respectively. Compared to retrovirus-seronegative cats median survival time was significantly lower (P<0.000) in FeLV and FIV+FeLV-seropositive cats. Median survival time in FeLV and FIV+FeLV-seropositive cats was also significant lower (P<0.000) when compared to FIV-seropositive cats. Hazard ratio of death in FeLV and FIV+FeLV-seropositive cats being respectively 3.4 and 7.4 times higher, in comparison to seronegative cats and 2.3 and 4.8 times higher in FeLV and FIV+FeLV-seropositive cats as compared to FIV-seropositive cats.A Cox proportional-hazards regression analysis showed that FIV and FeLV-seropositive cats with reduced RBC counts at time of diagnosis of seropositivity had significantly shorter survival times when compared to FIV and FeLV-seropositive cats with normal RBC counts at diagnosis.In summary, FIV-seropositive status did not significantly affect longevity of cats in this study, unlike FeLV and FIV+FeLV-seropositivity. Reduced RBC counts at time of FIV and FeLV diagnosis could impact negatively on the longevity of seropositive cats and therefore blood counts should always be evaluated at diagnosis and follow-up of retrovirus-seropositive cats.

Consider the eye in preventive healthcare - ocular findings, intraocular pressure and Schirmer tear test in ageing cats.

Geriatric health screening in cats is highly recommended. However, information about normal and abnormal findings is scarce, especially regarding the eyes of ageing cats. This prospective study examined the influence of the ageing process on vision and ocular structures in older cats. A total of 209 cats (aged 9-24 years) underwent physical examination, vision assessment, slit lamp biomicroscopy and ophthalmoscopy. Systolic blood pressure (SBP) measurement, Schirmer tear test (STT) reading and rebound tonometry were performed. Systemic disease was not a criterion for exclusion. Vision was good in 157/209 cats (75.1%) and impaired in 52/209 cats (24.9%). Increasing age and the occurrence of vision impairment were not statistically associated ( P = 0.053). Retinal oedema, retinal haemorrhage and/or retinal detachment (19 cats) and glaucoma (12 cats) were the most common findings in vision impaired cats. Increasing age was significantly associated with the occurrence of lenticular sclerosis ( P = 0.01) and attenuated retinal vessels ( P = 0.02). Increasing age and SBP were significantly associated with the occurrence of retinal detachment, haemorrhage and oedema ( P <0.001 each). In cats without evidence of hypertensive ocular damage, younger cats had a tendency for higher SBP values than older cats, although this difference was not significant. Mean intraocular pressure (IOP) was 16.5 ± 5.0 mmHg. Age did not significantly affect the IOP values ( P = 0.54). Mean STT was 15.8 ± 4.8 mm/min. The STT was found to increase with age ( P = 0.025). Although vision impairment is not a clinical sign of old age in cats, age-related changes may contribute to vision-threatening diseases. This study contributes to preventive healthcare by examining the influence of the ageing process on vision and ocular structures in older cats.

Testicular cytology by fine needle aspiration in domestic cats

In cases where semen collection in tom-cats is not possible, FNA of testes is the alternative to evaluate sperm production. Although this technique for the diagnosis of fertility problems has been well discussed in other mammals (men, dogs, stallions), data for domestic cats are limited. Therefore, the aim of this study was to verify the reliability of FNA using needles of small diameters (22G and 29G) in testes of domestic cats of different ages to assess the spermatogenesis status and to present description of germ cells and Sertoli cells for cytological examinations. Thirty-four mixed breed cats aged between four months and two years presented for neutering to a Veterinary Hospital were used in this study. Under general anesthesia, testicular measures and FNA were followed by orchiectomy and imprints of the parenchyma of testes and epididymides. Cats were assigned into 3 groups: (G1) 10 cats aged less than 6 months, (G2) 14 cats aged between 6 months and one year and (G3) 10 cats aged more than one year. Cats weighted between 1.5 and 6.0 kg. The mean testicular volume (TV cm3) was 0.55 (G1), 1.18 (G2) and 2.66 (G3). Hemorrhages in the needle path were observed in more than 70% of testes. Few samples (4/68) were excluded due to blood contamination. All germ cells and Sertoli cells were identified and quantified in imprint and FNA smears. Incomplete spermatogenesis was observed in cats aged less than 6 months using both techniques (FNA and imprint); therefore, testicular FNA should not be recommended for cats at this age. Complete spermatogenesis was found in 64% of cats aged from 6 months up to one year and in all cats aged more than one year. There were no differences of Sertoli cell Index (SEI) and Spermatic Index (SI) between FNA and imprints of cats older than 6 months. In conclusion, FNA using needles of small diameter in the testes of domestic cats is viable, reliable and can be used as a tool for the analysis of the spermatogenesis status of cats older than 6 months, mainly in cases in which semen collection is not possible.

Investigating Some of the Factors that Affect the Selection of Shelter Cats by Adopters in the Czech Republic

ABSTRACTRecords on cat adoptions were collected from three cat shelters situated in different regions of the Czech Republic. Originally, 2,170 cats were admitted to the monitored shelters; of which 1,407 (65%) cats were adopted in the period from 2011 to 2015. Significantly (p < 0.001) greater numbers of cats were adopted in autumn and winter than in spring and summer. The differences in the numbers of adopted cats of different sex, age, or coat color corresponded with the differences in proportions of these characteristics in cats admitted to the monitored shelters. No effect of sex on time to adoption was found. However, age and coat color affected the length of stay (LOS). Geriatric cats had the greatest and adult cats the shortest LOS. Kittens, juveniles, and young adults did not differ in LOS but they all stayed in shelters longer (p < 0.05) than adult cats. The median length of the stay of dark-colored cats was significantly greater (p < 0.001) than that of cats with a light or medium shade of coat color. Significantly (p < 0.001) more cats were adopted by women (748; 76.2%) than by men (233; 23.8%). Understanding seasonal fluctuations in cat adoptions and potential adopterś preferences is crucial for shelter personnel to establish effective procedures for rehoming shelter cats. Considering the relatively long time to adoption (median LOS = 69 days, mean LOS = 139 days, range = 0–1,600 days) more efforts should be put into seeking strategies for reducing this.

Preliminary description of aging cats and dogs presented to a New Zealand first-opinion veterinary clinic at end-of-life

AIMSTo conduct a preliminary investigation into the chronic disease conditions and clinical signs present in aging New Zealand companion animals at end-of-life and to describe the timing, circumstances, and manner of death.METHODSThe medical records database of a first-opinion, companion animal, veterinary practice in Auckland, New Zealand was searched to identify all canine and feline patients ≥7 years of age that were subjected to euthanasia or cremated in the period between July 2012–June 2014. The free-text medical notes were analysed for information on the circumstances surrounding the death, previous diagnoses of chronic disease conditions, and the presence of clinical signs associated with decreased quality-of-life at the time of euthanasia.RESULTSThe median age at death was 15 (max 22) years for the 130 cats and 12 (max 17) years for the 68 dogs in the study sample. Euthanasia at the clinic was carried out for 119/130 (91%) cats and 62/68 (91%) dogs, with the remainder recorded as having an unassisted death. The frequency of deaths was highest during December for both cats and dogs. Cost was mentioned as an issue in the medical records for 39/181 (21.6%) patients that were subjected to euthanasia. At the time of euthanasia, 92/119 (77.3%) cats and 43/62 (69.4%) dogs were recorded as having >1 clinical sign associated with a decreased quality-of-life. Inappetence and non-specific decline were the two most commonly recorded clinical signs for both dogs and cats. Cardiovascular disease (44/130, 34%), renal failure (40/130, 31%), and malignant neoplasia (36/130, 28%) were the most common chronic disease conditions recorded for cats. Degenerative joint disease (22/68, 32%), malignant neoplasia (14/68, 21%), and cardiovascular disease (8/68, 12%) were the most common chronic disease conditions recorded for dogs.CONCLUSIONS AND CLINICAL RELEVANCEThese preliminary findings highlight that aging companion animals in New Zealand frequently have chronic disease conditions and clinical signs that may potentially be associated with decreased quality-of-life at the time of death. Further in-depth studies are required to determine whether there is a greater role for veterinarians in counselling owners about end-of-life care and euthanasia decisions.

Active and passive responses to catnip (Nepeta cataria) are affected by age, sex and early gonadectomy in male and female cats

Catnip (Nepeta cataria) is a popular plant among cat owners because in about 60% of felids elicits active behaviors such as rolling over, grooming, motor activity and vocalizations. Herein, we assessed the display of active but also passive responses, such as time in sphinx-like position, and consequently hypothesized that 100% of cats respond to catnip. Accordingly, sixty domestic cats of different age (infant, juvenile, adults), sex (males, females) and gonadal status (early gonadectomized, gonadally intact) were placed in a cylindrical chamber (1.20×1.40m) during 5min and then exposed to 500mg of dehydrated catnip for another 5min. Behaviors were videorecorded and scored. Results indicated that about 20% of the cats (adults and juvenile only) displayed active behaviors (i.e. rolling over), whereas 80% displayed passive responses at any age (sphinx-like position, decreased frequency in vocalizations, and decreased motor activity). These results suggest that all cats respond to catnip but they express it actively, passively or with a combination of both types of responses, which mainly depends on age and sex, and early gonadectomy to a much less extent. We discuss the possible implications of brain maturation on this dichotomy and speculate on the role of opioidergic system on the catnip responses.

Serum concentrations of symmetric dimethylarginine and creatinine in cats with kidney stones.

Serum concentrations of symmetric dimethylarginine (SDMA) correlate with renal function in cats and SDMA has been shown to be a more reliable and earlier marker for chronic kidney disease (CKD) compared with serum creatinine (Cr). Calcium oxalate uroliths tend to develop in mid-to-older aged cats and kidney stones may cause a reduction in renal function with increased SDMA, but normal serum Cr. The purpose of this retrospective study was to determine if cats with kidney stones had increased serum SDMA concentrations, and whether SDMA increased earlier than serum creatinine concentrations. Cats in the colony with kidney stones diagnosed between August 2010 and December 2015 (n = 43) were compared with healthy geriatric cats (n = 21) without kidney stones. Serum SDMA concentrations were determined by liquid chromatography-mass spectrometry and serum Cr concentrations were determined by enzymatic colorimetry. Cats with kidney stones were diagnosed antemortem by radiographic imaging (n = 12) or by postmortem necropsy (n = 31). Retrospectively, serum SDMA was found to be increased above the upper reference limit in 39 of 43 cats with kidney stones. Serum Cr was increased above the upper reference limit in 18 of 43 cats; 6 of these 18 cats had terminal azotemia only. The mean time that serum SDMA was increased before serum Cr was increased was 26.9 months (range 0 to 60 months). Kidney stones were composed of calcium oxalate in 30 of 34 cats. The lifespan for cats with kidney stones (mean, 12.5 years; range, 6.1 to 18.1 years) was shorter (P < 0.001) than for control cats (mean, 15.2 years; range, 13.0 to 17.2 years), suggesting that non-obstructive kidney stones have an effect on mortality rate or rate of CKD progression. In conclusion, if SDMA concentrations are elevated in mid-to-older aged cats, further imaging studies are warranted to check for the presence of kidney stones.

Palisade Endings in Cat Extraocular Muscles Develop Postnatally Following Different Time Courses

Proprioception from extraocular muscles (EOMs) provides the brain with eye position signals. Surprisingly, classical proprioceptors (muscle spindles and Golgi tendon organs) are absent in the EOMs of most mammals. Instead, palisade endings (PEs) are found as unique to EOMs of mammals. They are regularly present in frontal‐eyed but infrequent in lateral‐eyed species. PEs are formed by axons which extend onto the tendon where axons make a u‐turn and divide into axonal branches that establish nerve terminals around the tip of a single muscle fiber. For a century, PEs have been considered as sensory structures substituting classical proprioceptors in EOMs. The interest in PEs has newly aroused when molecular analysis and recent neuronal tracing experiments have shown that PEs are cholinergic and originate from the EOM motor nuclei.Since the development of PEs is unknown, we have analyzed their postnatal maturation in a frontal‐eyed species (cat). Cats of different ages (P0, P8, P22, and adult) were used and whole mount preparation of the rectus EOMs were triple‐immunolabelled and analyzed in the CLMS. Triple labelling included antibody against neurofilament (to label axons), anti‐synaptopysin (to label nerve terminals), anti‐growth associated protein43 (GAP43, to label developing axons), and phalloidin (to label muscle fibers).At P0, no PEs were found in the rectus muscles. However, in the medial rectus we found axons extending straight onto the tendon where they extensively sprouted to establish synaptophysin‐positive contacts. At P8, premature PEs were found in the medial rectus but not in the other rectus muscles. At P22, the complexity of PEs in the medial rectus had increased noticeably and formation of PEs had started in the inferior rectus. At this stage PEs were still absent in the lateral rectus and superior rectus muscle. In the adult animal, all rectus muscles contained PEs. GAP43, a marker for developing axons was highly expressed in premature PEs. GAP43 expression decreased with age and was nearly absent in PEs of adult animals.Here we show that the development of PEs in the rectus muscles occurs in a staggered fashion and is more accelerated in the medial rectus. Recently we have shown that in frontal‐eyed species many more PEs are present in the medial rectus compared with the other rectus muscles. The preponderance and the quicker maturation of PEs in the medial rectus support the notion that PEs could play a role in convergence.

Development of enzyme immunoassays (ELISA and Western blot) for the serological diagnosis of dermatophytosis in symptomatic and asymptomatic cats

Dermatophytosis is the most common fungal infection in cats worldwide and plays an important role in both animal and human health due to their high zoonotic potential. Effective screening is a strong preventive measure and the fungal culture is quite useful but requires full laboratorial experience and it takes a long time to obtain the result. A rapid and accurate screening test for dermatophytosis in cats is crucial for the effective control of disease outbreaks. The aim of this study was to develop and evaluate the diagnostic efficacy of enzyme immunoassays (ELISA and Western blot [WB]) for the rapid and precise diagnosis of dermatophytosis in cats. Seventy cats of various ages were divided into three groups: S (symptomatic, n = 20), AS (asymptomatic, n = 30), and N (negative, n = 20). All animals were submitted to fungal culture and blood samples for carrying out the serological tests. A significant difference (P < 0.05) was found between IgG-specific levels of sera of Microsporum canis positive and negative animals. There was no statistic difference between groups symptomatic and asymptomatic. The ELISA test showed sensitivity of 94% and specificity of 75%. Receiver operating characteristic (ROC) analysis also showed higher diagnostic accuracy (AUC 0.925). The WB technique detected 13 bands, and the 50kDa protein was considered the most immunogenic protein, observing reactivity in 83.3% in the symptomatic group and 66.6% in the asymptomatic group. The study concluded that ELISA and WB were useful tools to reliably detect cats that have been exposed to M. canis.

The effect of position on the precision of dual-energy X-ray absorptiometry and correlation with body condition score in dogs and cats.

Dual-energy X-ray absorptiometry (DEXA) has been used to assess body composition in dogs and cats in several studies, but studies are difficult to compare for several reasons. The aim of the present study was to evaluate whether positioning of dogs or cats in either dorsal or ventral recumbency during DEXA scanning influences results. Dogs and cats that were brought to the University Hospital for Companion Animals for euthanasia during the period 15 September-6 November 2015 were consecutively recruited if owners signed a written consent. Following euthanasia and before rigor mortis, the animals were body condition scored (BCS, nine-point scale) and DEXA scanned. DEXA measurements of total body mass (TBM), bone mineral content (BMC), bone mineral density (BMD), lean soft tissue mass (LSTM) and body fat (BF) were performed five times in ventral and two times in dorsal recumbency on each animal. Differences between positioning were analysed using Student's t test or Wilcoxon's test depending on normality of the data. A total of thirteen dogs and seven cats of different breeds, size, sexes and age were included. The CV for DEXA parameters in ventral or dorsal recumbency were, for dogs, TBM ≤ 0·1 %, BMC ≤ 1·63 %, BMD ≤ 1·29 %, LSTM ≤ 0·89 % and BF ≤ 1·52 %; and, for cats, TBM ≤ 0·08 %, BMC ≤ 0·61 %, BMD ≤ 0·49 %, LSTM ≤ 0·45 % and BF ≤ 0·88 %. In both positions, a good correlation was found for dogs (r 0·84-0·85; P < 0·0003) and cats (r 0·89-0·90; P < 0·0081) between the nine-point BCS system and BF percentage measured by DEXA. Ventral and dorsal recumbency provides comparable results, except that BMD measures were higher in dorsal recumbency (P < 0·0004).

In vitro screening of neuroprotective activity of Indian medicinal plant Withania somnifera.

Canine cognitive dysfunction (CCD) is an age-dependent neurodegenerative condition characterised by changes in decline in learning and memory patterns. The neurodegenerative features of CCD in ageing dogs and cats are similar to human ageing and Alzheimer's disease (AD). Discovering neuroprotective disease-modifying therapies against CCD and AD is a major challenge. Strong evidence supports the role of amyloid β peptide deposition and oxidative stress in the pathophysiology of CCD and AD. In both the human and canine brain, oxidative damage progressively increases with age. Dietary antioxidants from natural sources hold a great promise in halting the progression of CCD and AD. Withania somnifera (WS), an Ayurvedic tonic medicine, also known as 'Indian ginseng' or ashwagandha has a long history of use in memory-enhancing therapy but there is a dearth of studies on its neuroprotective effects. The objective of this study was to investigate whether WS extract can protect against Aβ peptide- and acrolein-induced toxicity. We demonstrated that treatment with WS extract significantly protected the human neuroblastoma cell line SK-N-SH against Aβ peptide and acrolein in various cell survival assays. Furthermore, treatment with WS extract significantly reduced the generation of reactive oxygen species in SK-N-SH cells. Finally, our results showed that WS extract is also a potent inhibitor of acetylcholinesterase activity. Thus, our initial findings indicate that WS extract may act as an antioxidant and cholinergic modulator and may have beneficial effects in CCD and AD therapy.

ДЕЯКІ МАКРОСКОПІЧНІ ЗМІНИ У ВНУТРІШНІХ ОРГАНАХ КОТІВ, ЩО ЗАГИНУЛИ ВІД КАЛІЦИВІРУСНОЇ ІНФЕКЦІЇ

Calicivirus infection of cats is a highly contagious disease of animals of the cat family, which is clinically manifested by conjunctivitis, ulcerative stomatitis, rhinitis, tracheobronchitis, pneumonia, and accompanied by significant mortality. This infection is widespread in populations of domestic and wild felines throughout the world.According to modern world literature the manifestation of the disease depends on the strain of the pathogen. Depending on the strain infected with caliciviruses studs in some cases can be clinically healthy, others have ulcers on the mucous membranes of the oral cavity and the symptoms are not much pronounced pneumonia. Less frequently recorded disease that is accompanied by lameness, abortions and severe pneumonia. However, the death of all forms recorded very rarely. According to many authors media avirulence and weakly virulent strains calicivirus of infection is 36% of cats.However, in the last decade were also recorded epizootics of severe disease, mortality is up to 50%. Clinically the disease was characterized by oppression, high continued fever, anorexia, edema of face and extremities, with lesions of dermatitis or alopecia on the face, ears and distal parts of the limbs. In the literature adequately described the etiology, pathogenesis, clinical presentation, and treatment of this disease, and pathological changes are described is not complete. In particular macroscopic changes at calicivirus infection, most authors describe conjunctivitis, stomatitis and pneumonia. The aim of this study was to examine in more detail the macroscopic changes in the internal organs of cats of various ages and breeds, died of calicivirus infection. the following tasks were set to achieve this goal, namely to carry out post–mortem dissection of cats with calicivirus infection to study the macroscopic changes in the internal organs in cats this disease and in detail describe the macroscopic changes in the internal organs of cats, not previously described.The material for the study were the corpses of five cats of various ages, who died of calicivirus infection. Autopsy corpses of cats was performed by partial evisceration at the Department of Pathological Anatomy of the National University of Life and Environmental Sciences of Ukraine. At postmortem autopsy in cats killed by calicivirus infection indicate catarrhal conjunctivitis, acute catarrhal rhinitis, stomatitis, glossitis, edema and serous and serosanguineous lymphadenitis, and venous congestion and pulmonary edema, liver hyperemia, Muscat. Observed myogenic dilatation of the heart and catarrhal duodenitis.

Effects of Aging and Oxidative Stress on Spermatozoa of Superoxide-Dismutase 1- and Catalase-Null Mice.

Advanced paternal age is linked to complications in pregnancy and genetic diseases in offspring. Aging results in excess reactive oxygen species (ROS) and DNA damage in spermatozoa; this damage can be transmitted to progeny with detrimental consequences. Although there is a loss of antioxidants with aging, the impact on aging male germ cells of the complete absence of either catalase (CAT) or superoxide dismutase 1 (SOD1) has not been investigated. We used CAT-null (Cat−/−) and SOD1-null (Sod−/−) mice to determine whether loss of these antioxidants increases germ cell susceptibility to redox dysfunction with aging. Aging reduced fertility and the numbers of Sertoli and germ cells in all mice. Aged Sod−/− mice displayed an increased loss of fertility compared to aged wild-type mice. Treatment with the pro-oxidant SIN-10 increased ROS in spermatocytes of aged wild-type and Sod−/− mice, while aged Cat−/− mice were able to neutralize this ROS. The antioxidant peroxiredoxin 1 (PRDX1) increased with age in wild-type and Cat−/− mice but was consistently low in young and aged Sod−/− mice. DNA damage and repair markers (γ-H2AX and 53BP1) were reduced with aging and lower in young Sod−/− and Cat−/− mice. Colocalization of γ-H2AX and 53BP1 suggested active repair in young wild-type mice but reduced in young Cat−/− and in Sod−/− mice and with age. Oxidative DNA damage (8-oxodG) increased in young Sod−/− mice and with age in all mice. These studies show that aged Sod−/− mice display severe redox dysfunction, while wild-type and Cat−/− mice have compensatory mechanisms to partially alleviate oxidative stress and reduce age-related DNA damage in spermatozoa. Thus, SOD1 but not CAT is critical to the maintenance of germ cell quality with aging.

Evaluation of the Leptospira species microscopic agglutination test in experimentally vaccinated cats and Leptospira species seropositivity in aged azotemic client-owned cats.

The objectives of this study were to validate the microscopic agglutination test (MAT) using feline sera, determine cross-reactivity of Borrelia burgdorferi antibodies in the MAT, and evaluate if there is an association between Leptospira species seropositivity in aged (⩾10 years) client-owned cats with and without azotemia (creatinine >2 g/dl). A four-serovar canine leptospiral vaccine was administered to two specific pathogen-free (SPF) cats on days 0 and 14. The MAT was performed intermittently until day 42 for the serovars Canicola, Grippotyphosa, Hardjo, Icterohaemorrhagiae, Pomona and Bratislava, with a cut-off value of ⩾1:100. Five purpose-bred cats were infested with wild-caught Ixodes scapularis adults with an average B burgdorferi infection rate of 50%, and tested for antibodies against B burgdorferi C6 peptide and DNA in skin biopsies, as well as by MAT. Sera from 66 azotemic and 75 non-azotemic cats ⩾10 years of age were tested for Leptospira species antibodies using the MAT and results were compared by the χ(2) test. Both SPF cats seroconverted by week 3 and formed antibodies against at least one serovar. There was no cross-reactivity in the MAT using samples from cats with antibodies to B burgdorferi. MAT results were positive for 4/66 azotemic cats and 8/75 non-azotemic cats; these results were not statistically different. The MAT can be interpreted using feline serum and does not appear to cross-react in cats with B burgdorferi antibodies. There was no association between Leptospira species MAT results and azotemia in this group of aged client-owned cats but further studies are needed to determine if leptospirosis contributes to feline chronic kidney disease.

Evaluating aging in cats: How to determine what is healthy and what is disease.

Many of the changes that occur with aging are not considered pathologic and do not negatively affect overall wellness or quality of life. Ruling out disease is essential, however, when attempting to determine whether an aged cat can be considered 'healthy'. A clear understanding of the normal and abnormal changes that are associated with aging in cats can help practitioners make decisions regarding medical management, feeding interventions and additional testing procedures for their aged patients. It can be difficult to determine if a cat is displaying changes that are appropriate for age. For example, healthy aged cats may have hematologic or serum biochemistry changes that differ from those of the general feline population. Assessment of behavioral health and cognitive changes, as well as auditory, olfactory and visual changes, can also be challenging in the aged patient. This is the second of two review articles in a Special Issue devoted to feline healthy aging. The goals of the project culminating in these publications included developing a working definition for healthy aging in feline patients and identifying clinical methods that can be used to accurately classify healthy aged cats. This second review proposes criteria for assessing 'healthy aged cats'. There is a paucity of research in feline aging. The authors draw on expert opinion and available data in both the cat and other species.

Aging in cats: Common physical and functional changes.

Aged pets comprise a significant proportion of the small animal veterinarian's patient population; in the USA, for example, it was estimated that over 20% of pet cats were 11 years of age or older in 2011. Certain changes associated with aging are neither positive nor negative, but others are less desirable, associated with illness, changes in mobility or the development of unwanted behaviors. These changes can greatly affect the health and wellbeing of the cat and have a tremendous impact on the owner. Regular veterinary examinations are essential for evaluating the health of older patients and for providing owners with guidance regarding optimal care. With the exception of overt disease, however, it is difficult to definitively determine if a cat is displaying changes that are appropriate for age or if they reflect an abnormal process or condition. This is the first of two review articles in a Special Issue devoted to feline healthy aging. The goals of the project culminating in these publications included developing a working definition for healthy aging in feline patients and identifying clinical methods that can be used to accurately classify healthy aged cats. This first review provides a thorough, systems-based overview of common health-related changes observed in cats as they age. There is a paucity of research in feline aging. The authors have drawn on expert opinion and available data in both the cat and other species.

Geriatric cats: care within the veterinary practice

Understanding the needs of the geriatric cat is paramount to ensure correct management of these patients within the veterinary practice. It is important to recognise those conditions which can affect the ageing cat as well as the environmental modifications which are applicable to its wellbeing and normal functionality within the veterinary environment. Client education should be at the forefront of the veterinary practice to aid in the management of the geriatric patient and also help with the detection of early disease onset.

Response: Commentary: Age-related neurodegenerative disease research needs aging models.

In response to my recent article (Johnson, 2015), Wallace and Howlett have provided a thoughtful commentary pointing out that aging might be defined not just by the passage of time, but by the accumulation of defects in multiple regions throughout the organism that can be represented by a frailty index (Wallace and Howlett, 2016). It occurs to me that this approach might help overcome two major barriers to aging research: (i) the time taken for animals to age, and (ii) the fact that animals tend to die as they age. In our research on aging (24 m-old) ad-libitum fed rats, we found approximately 50% of animals died before the age of 24 m. In contrast, caloric-restricted rats did not die before they reached 24 m, did not show typical age-related pathologies, and had motoneurones that responded differently to injury compared to age-matched ad-libitum-fed rats (Aperghis et al., 2003; Johnson and Duberley, 1998). For 10–15-years-old ad-libitum fed cats we also found increasing health problems with age, but no evidence that the spinal motoneurones in these aging cats were any more vulnerable to injury than those in 1–2-years-old cats (Johnson et al., 1991). It would be interesting to know if the creation in younger animals of age-related defects, such as those associated with metabolic syndrome or changes in inflammatory status, also causes nervous system pathologies typical of aging. Such models may well be quicker and cheaper than aging animals. They might also remove the criticism that results obtained from the study of aging animals are unrepresentative because they are based on the “survivors.” The use of a frailty index to determine age and perhaps create artificially aged models is an exciting concept, notwithstanding the possibility that the largely post-mitotic population of neurones in the nervous system may respond differently to cells in the rest of the organism.

The domestic cat as a natural animal model of Alzheimer's disease.

IntroductionAlzheimer’s disease (AD) is the most dominant neurodegenerative disorder that causes dementia, and no effective treatments are available. To study its pathogenesis and develop therapeutics, animal models representing its pathologies are needed. Although many animal species develop senile plaques (SP) composed of amyloid-β (Aβ) proteins that are identical to those found in humans, none of them exhibit neurofibrillary tangles (NFT) and subsequent neurodegeneration, which are integral parts of the pathology of AD.ResultsThe present study shows that Aβ accumulation, NFT formation, and significant neuronal loss all emerge naturally in the hippocampi of aged domestic cats. The NFT that form in the cat brain are identical to those seen in human AD in terms of their spatial distribution, the cells they affect, and the tau isoforms that comprise them. Interestingly, aged cats do not develop mature argyrophilic SP, but instead accumulate intraneuronal Aβ oligomers in their hippocampal pyramidal cells, which might be due to the amino acid sequence of felid Aβ.ConclusionsThese results suggest that Aβ oligomers are more important than SP for NFT formation and the subsequent neurodegeneration. The domestic cat is a unique animal species that naturally replicates various AD pathologies, especially Aβ oligomer accumulation, NFT formation, and neuronal loss.Electronic supplementary materialThe online version of this article (doi:10.1186/s40478-015-0258-3) contains supplementary material, which is available to authorized users.

The effects of social interaction and environmental enrichment on the space use, behaviour and stress of owned housecats facing a novel environment

Every day, millions of domestic cats are held temporarily in captive environments, such as boarding catteries and rescue shelters. Being in confinement can potentially invoke high levels of stress for these animals. Therefore, there is a need to develop appropriate strategies to reduce these effects. Here, we investigated the effect of physical (inclusion of different objects) and social (extended social interaction with carers) alterations to the environment of owned neutered cats in confinement on their level of stress. To assess stress levels we used behavioural stress scoring (Cat Stress Score: CSS), faecal glucocorticoid metabolite analysis and CCTV recordings. We examined how cats used objects/space in confinement, if spatial preferences and behaviour were related to stress load, and if stress load was affected by social interaction. We calculated an electivity index, which measures utilisation of features in proportion to its availability in the environment, to show that cats displayed a preference for concealed areas and raised vantage points over large open spaces and owner-scented resting areas. Results of linear mixed models indicated that cats with the highest behavioural stress scores spent less than half as much time in open areas as cats with the lowest stress scores (P=0.023). Furthermore, cats with the highest behavioural stress scores spent 10% more time in passive behaviours (P=0.008), suppressed essential maintenance behaviours (P<0.001) and exhibited approximately half the number of different behaviours (P=0.008) compared with cats with the lowest stress scores. Extended social interaction with carers reduced behavioural stress scores from day 1 to day 2 (CSS 3.22–3.00; P=0.028). Individual characteristics of cats affected stress, as cats with no previous experience in confinement (CSS for inexperienced cats 1.75 points higher than experienced cats of the same age; P=0.033), older cats (0.21 increase in CSS for each year; P=0.022) and male cats (CSS 1.17 points higher than female cats of the same age; P=0.037) were more stressed. Our results show that cats with particular attributes are more vulnerable to experiencing stress in confinement and highlight that certain behaviours in confinement indicate more stressed individuals. However, stress may be effectively reduced through extended interactions with carers, and enriching the captive environment through addition of hiding spots and vertical climbing structures.