MOESM1 of Occurrence of cardiorespiratory diseases and impact on lifespan in Swedish Irish Wolfhounds: a retrospective questionnaire-based study

Additional file 1: Questionnaire. A translated English version of the questionnaire distributed to owners of purebred Irish Wolfhounds born during 2006–2008

The urine metabolome differs between lean and overweight Labrador Retriever dogs during a feed-challenge

<div><p>Obesity in dogs is an increasing problem and better knowledge of the metabolism of overweight dogs is needed. Identification of molecular changes related to overweight may lead to new methods to improve obesity prevention and treatment. The aim of the study was firstly to investigate whether Nuclear Magnetic Resonance (NMR) based metabolomics could be used to differentiate postprandial from fasting urine in dogs, and secondly to investigate whether metabolite profiles differ between lean and overweight dogs in fasting and postprandial urine, respectively. Twenty-eight healthy intact male Labrador Retrievers were included, 12 of which were classified as lean (body condition score (BCS) 4–5 on a 9-point scale) and 16 as overweight (BCS 6–8). After overnight fasting, a voided morning urine sample was collected. Dogs were then fed a high-fat mixed meal and postprandial urine was collected after 3 hours. Metabolic profiles were generated using NMR and 45 metabolites identified from the spectral data were evaluated using multivariate data analysis. The results revealed that fasting and postprandial urine differed in relative metabolite concentration (partial least-squares discriminant analysis (PLS-DA) 1 comp: R²Y = 0.4, Q²Y = 0.32; cross-validated ANOVA: <i>P</i> = 0.00006). Univariate analyses of discriminant metabolites showed that taurine and citrate concentrations were elevated in postprandial urine, while allantoin concentration had decreased. Interestingly, lean and overweight dogs differed in terms of relative metabolite concentrations in postprandial urine (PLS-DA 1 comp: R²Y = 0.5, Q²Y = 0.36, cross-validated ANOVA: <i>P</i> = 0.005) but not in fasting urine. Overweight dogs had lower postprandial taurine and a trend of higher allantoin concentrations compared with lean dogs. These findings demonstrate that metabolomics can differentiate 3-hour postprandial urine from fasting urine in dogs, and that postprandial urine metabolites may be more useful than fasting metabolites for identification of metabolic alterations linked to overweight. The lowered urinary taurine concentration in overweight dogs could indicate alterations in lipid metabolism and merits further investigation.</p></div

Supplement Figure 1

The stability of cardiac troponin I (cTnI) concentration in serum samples from three cats with hypertrophic cardiomyopathy (HCM) after storage in the dark at 20°C</p

Supplement Table 2

Auscultation, basic echocardiographic and laboratory variables in 96 healthy cats and 39 cats with hypertrophic cardiomyopathy (HCM)</p

Dietary history of the 28 Labrador Retriever dogs included in the study^a.

<p>Dietary history of the 28 Labrador Retriever dogs included in the study<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0180086#t001fn001" target="_blank">^a</a>.</p

Principal component analysis between fasting and postprandial time points.

<p>Fasting and postprandial urine samples showed a clear separation in principal component analysis (A). All 45 metabolites and all 28 dogs were included in this unconstrained model. Principal component (PC) 1 explained 12% of the variance and PC2 7%. The separation proved significant in a partial least-squares discriminant analysis (PLS-DA) model (for <i>P</i>-values, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0180086#sec009" target="_blank">Results</a> section) where fasting and postprandial urine samplings were pre-defined as two separate groups. Loading plot (B) corresponds to the principal component analysis (A). Discriminative metabolites making a significant contribution to the separation between fasting and postprandial urine in the PLS-DA model (allantoin, taurine, citrate and malonate) are highlighted in bold text and with black dots.</p

Discriminant metabolites between fasting and postprandial time points in the 28 included Labrador Retriever dogs.

<p>Discriminant metabolites between fasting and postprandial time points in the 28 included Labrador Retriever dogs.</p

Discriminant metabolites between lean and overweight Labrador Retriever dogs in postprandial urine.

<p>Discriminant metabolites between lean and overweight Labrador Retriever dogs in postprandial urine.</p

Supplement Table 1

Auscultation, basic echocardiographic and laboratory variables in 96 healthy Birman, Domestic Shorthair (DSH), and Norwegian Forest (NF) cats</p

Supplement 1 Stability study

The concentration of cTnI decreased in serum samples stored at 20°C. After three days, the mean decrease was 4% in comparison with the initial value. Mean decrease was 14% after 5 days and 20% after 7 days (Supplement Figure 1). The cTnI concentration changed from -1 to 5% after three freeze-thaw cycles.</p