Starch and moisture content of food and urinary supersaturation for calcium oxalate in cats

• Grant number: 22/03373-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2022
• End date: May 31, 2023
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal Investigator: Aulus Cavalieri Carciofi
• Grantee: Pablo da Cunha Costa
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

Cats are carnivorous animals, with a high need for amino acids. The use of starch by these animals has already been studied, however, there is still information that is not well clarified for the species, especially regarding its potential effect on the endogenous formation of oxalate. Of desert origin, cats present more concentrated urine when fed with dry kibble. The objectives of this study are to evaluate the effect of consuming diets with different ratios between starch and protein and different moisture contents on renal oxalate excretion, water balance, and the urine relative supersaturation index (RSS) for calcium oxalate. The treatments will be organized in a 2 x 2 factorial scheme, represented by two proportions of starch (15% versus 30%) and protein (34% versus 50%, based on the dry matter) and two moisture contents (8% versus 80% ), totaling 4 experimental treatments. Thirty-six adult cats will be used, organized in a randomized block design, with 3 blocks of 12 cats, 3 cats per diet in each block, totaling 9 replications (cats) per diet. In each block, the cats will remain for ten days in adaptation, followed by eight days of the total collection of urine and feces (animals restricted to metabolic cages). In the urine produced in 24 hours, the volume, density, and pH will be measured. Additionally, in the urine composed of animal and period, the contents of calcium, phosphorus, chlorine, sulfur, magnesium, sodium, potassium, citrate, oxalate, uric acid, creatinine, and ammonia will be determined. In the feces, weight, score and moisture will be measured. Food and water consumption will be measured daily. Based on these results, the water balance will be established and the urine SSR for calcium oxalate will be calculated. The results will be submitted for analysis of variance considering the effects of starch: protein ratio, moisture content, and their interaction (P<0.05).(AU)