Beneficial effects of a prescription home-prepared diet and of zucchini on urine calcium oxalate supersaturation and urinary parameters in adult cats.

OBJECTIVES: From the authors' experience, the consumption of a balanced prescription home-prepared diet that includes zucchini (courgette) benefits cats with recurrent urolithiasis, but there is no published evidence to support this. The aim was to study the effects on urinary parameters of (1) a balanced prescription home-prepared diet containing zucchini, and (2) the addition of zucchini to a dry food, compared with two commercial therapeutic diets. METHODS: Eight healthy cats were included in a Latin-square designed protocol. Five diets were evaluated: two commercial diets, designed for cats with urinary disorders, one high-moisture (U-WET) and one high-sodium dry (U-DRY); one home-prepared diet (HOME); one commercial dry food for adult maintenance (DRY); and DRY given together with 10 g of zucchini per kg body weight (DRY-Zuc). After a 7-day adaptation period, urine was collected and daily food and water intakes were assessed for 12 days. Urinary parameters, and relative supersaturation (RSS) for calcium oxalate (CaOx) and struvite, were determined. Data underwent repeated measures ANOVA analysis. RESULTS: The digestibility of energy, dry matter, protein and fat was highest with the HOME diet. CaOx RSS was lowest in cats eating the HOME diet, but not significantly different from the U-WET or U-DRY diets. CaOx RSS was lower in cats eating the DRY-Zuc diet than in cats eating the DRY diet. Struvite RSS did not differ significantly among groups. CONCLUSIONS AND RELEVANCE: This study shows that a balanced prescription home-prepared diet was safe and allowed a very low urinary CaOx RSS. It also showed that adding zucchini to dry food lowered the urine CaOx RSS.

A mixed grape and blueberry extract is safe for dogs to consume.

BACKGROUND: Grape and blueberry extracts are known to protect against age-related cognitive decline. However, beneficial effects achieved by mixing grape and blueberry extracts have yet to be evaluated in dogs, or their bioavailability assessed. Of concern to us were cases of acute renal failure in dogs, after their ingestion of grapes or raisins. The European Pet Food Industry Federation (2013) considers only the grape or raisin itself to be potentially dangerous; grape-seed extracts per-se, are not considered to be a threat. Our aim was therefore to evaluate the renal and hepatic safety, and measure plasma derivatives of a polyphenol-rich extract from grape and blueberry (PEGB; from the Neurophenols Consortium) in dogs. Polyphenol expression was analyzed by UHPLC-MS/MS over 8 hours, for dogs given PEGB at 4 mg/kg. Safety was evaluated using four groups of 6 dogs. These groups received capsules containing no PEGB (control), or PEGB at 4, 20, or 40 mg/kg BW/d, for 24 weeks. Blood and urine samples were taken the week prior to study commencement, then at the end of the 24-wk study period. Routine markers of renal and liver damage, including creatinine (Creat), blood urea nitrogen, albumin, minerals, alkaline phosphatase (ALP), and alanine transaminase (ALT) were measured. Biomarkers for early renal damage were also evaluated in plasma (cystatin C (CysC), and neutrophil gelatinase-associated lipocalin (NGAL)), and urine (CysC, clusterin (Clu), and NGAL). Ratios of urinary biomarkers to Creat were calculated, and compared with acceptable maximal values obtained for healthy dogs, as reported in the literature. RESULTS: While several PEGB-specific polyphenols and metabolites were detected in dog plasma, at the end of the PEGB consumption period, our biomarker analyses presented no evidence of either renal or liver damage (Creat, BUN, ionogram, albumin and ALT, ALP). Similarly, no indication of early renal damage could be detected. Plasma CysC, urinary CysC/Creat, Clu/Creat, and NGAL/Creat ratios were all beneath reported benchmarked maximums, with no evidence of PEGB toxicity. CONCLUSIONS: Long-term consumption of a pet specific blend of a polyphenol-rich extract from grape and blueberry (PEGB; from the Neurophenols Consortium), was not associated with renal or hepatic injury, and can therefore be considered safe.

Prevalence and risk factors of obesity in an urban population of healthy cats.

The incidence of overweight in cats has been reported in various studies to range between 6 and 52% depending on such factors as gender, neutering, age, being cross-bred, living in a single or two-cat household, no dog living in the household, inactivity, feeding fresh meat or fish, eating a premium or therapeutic food, distribution of food on a free choice basis and owner underestimation of their cat's body weight or body condition (BC). The purpose of this study was to assess the prevalence of overweight and to determine the risk factors associated with excess body weight, including owners' perception of their cat's BC in the studied population. Between March and June 2006, all owners presenting healthy cats for vaccination at the National Veterinary School of Alfort were questioned by a veterinarian using a standardised and validated questionnaire. Owners and veterinarians gave an oral evaluation of the cat's BC first verbally and then by comparison with a legend free visual scale. Univariate analysis was performed for all variables. Multivariate logistic regression analysis was applied to variables strongly associated with overweight or regarded as major risk factors. On a total population of 385 cats, 19.0% were found to be overweight and 7.8% to be obese. The evaluation of overweight cats' BC by their owner was better with the visual scale than with the verbal description. This study confirmed earlier reports identifying being male, neutering, and underestimation of the cat's BC by the owner, as risk factors for being overweight.