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.

Evaluation of eight commercial dog diets.

Estimation of the quality of commercial diets is a topic of interest for the majority of dog owners. Recently, in a French consumer association magazine, an evaluation of eight dog commercial dry diets (from super-premium, basic-nutrition, private-label and economy brands) according to several nutritional criteria was published. The aims of the study were: (1) to evaluate the apparent digestibility of these diets; (2) to score these diets according to digestibility results; and (3) to compare these data with the scoring of the magazine. Six adult Beagle dogs were enrolled for the digestibility trials. Diets were scored according to energy, crude protein and crude fat (CF) apparent digestibility coefficients, digestible protein-to-energy ratios and ash content. Each of the five criteria was scored from 4 to 20 points. The ranges of crude protein, CF, crude fibre and ash content were 20·9-30·6 %, 6·8-19·7 %, 2·2-3·3 % and 4·6-9·7 % on a DM basis, respectively. The ranges of energy, crude protein and CF apparent digestibility coefficients were 72·6-87·7 %, 70·4-82·5 % and 76·1-95·4 %, respectively. The range of the protein-to-energy ratio was 10-14 digestible crude protein per MJ metabolisable energy. Little overlap in the scoring systems was found, but the private-label brand and economy brand diets presented the lowest scores in the two systems. These results showed that the evaluation of commercial diets should take into account multiple nutritional aspects. In particular, analytical and biological (digestibility) criteria should be considered as complementary in the evaluation of dry dog commercial diets.