Evaluation of the effects of long-term consumption of a grain-free food with a high pea content on the nutrients apparent digestibility, bile acids fecal excretion, ecodopplercardiographic variables, myocardial function biomarkers, taurine status and metabolomics in adult dogs

• Grant number: 21/02168-2
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: August 01, 2021
• End date: October 15, 2023
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Júlio Cesar de Carvalho Balieiro
• Grantee: Rafael Vessecchi Amorim Zafalon
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Foods labeled as "grain free" have gained increasing popularity among pet owners, which mainly happen due to the popular belief that traditional cereal grains are harmful to dogs and cats. In general, these foods are composed of high legumes levels, such as peas and lentils, in addition to potatoes. In recent years, many cases of Dogs with Dilated Cardiomyopathy (DCM) caused by taurine deficiency, who were consuming grain-free foods have been reported, a fact that prompted the FDA to publish a note alerting veterinarians and dog owners about the risks of consuming these foods. However, it is not yet proven that the consumption of these foods can cause DCM, as these case reports do not prove a cause and effect relationship. Considering those facts, the objective of this study is to evaluate the effects of long-term consumption of a grain-free food with high peas inclusion in echocardiographic variables, biomarkers of myocardial function, taurine status, nutrients apparent digestibility and metabolomics in healthy adult dogs, in order to investigate whether this type of diet can cause DCM and the possible factors that would be involved. 12 healthy adult beagle dogs will be included, and they will receive 2 different foods. One food (test food) will be formulated as a traditional cereal grains-free, with high pea content, and the other food will contain grains (in substitution of peas for corn) and it will be used as a control food (Control food). A cross-over design will be carried out, with 2 treatments and 2 periods, so all animals will consume all foods, and each period will last 9 months. At the beginning of the experiment and at the end of each period the following evaluations will be carried out: ecocodopplercardiographic evaluation, plasma and whole blood sulfur amino acids measurements, plasma biomarkers of myocardial function evaluation, fecal bile acids analyzes and metabolomics. At the end of each period, the nutrients apparent digestibility will be tested. The residues normality will be verified by the Shapiro Wilk test. For metabolomic analysis, the softwares MatLab (R2010) and Chenomix RNM suite 7.7 will be used for data chemometric evaluation and metabolites identification and quantification, respectively. The final quantitative values of all analyzes will be evaluated by ANOVA with repeated measures over time, when they obey the statistical premises and, in case of non-parametric data, the Wilcoxon test will be used. The software used will be the Statistical Analysis System (SAS, version 9.4). Values of p <0.05 will be considered significant. (AU)