The Influence of Giardia duodenalis on the Occurrence of Clinical Signs in Dogs.

Giardia duodenalis infections are common in dogs and are mainly caused by assemblages C and D. The aim of this study was to investigate the correlation between the presence of Giardia duodenalis and different Giardia assemblages detected in symptomatic and asymptomatic dogs and the occurrence of certain clinical signs. All the dogs included (n = 82) were clinically examined, and fecal samples were examined for other parasites and Clostridium spp. Also, G. duodenalis assemblages were detected and the occurrence of certain clinical signs was assessed. A total of 42/82 (51.2%) dogs were symptomatic and had one or more gastrointestinal signs, and 40/82 (48.8%) dogs were asymptomatic. G. duodenalis was found in 25/82 (30.5%) dogs: assemblage C in 10/25 (40%) and assemblage D in 15/25 (60%). Only Cryptosporidium spp. showed a higher coinfection rate with G. duodenalis but that did not have an influence on clinical sign appearance. There was no correlation between the presence of different assemblages of G. duodenalis and the sex of the host or the duration and appearance of certain clinical signs, except the presence of mucus in feces, which was more frequent in dogs invaded with G. duodenalis assemblage C. Further research of other assemblages is needed.

Metabolome Profiling in the Plasma of Dogs with Idiopathic Dilated Cardiomyopathy: A Multiplatform Mass-Spectrometry-Based Approach.

Dilated cardiomyopathy is one of the important diseases in dogs and humans. The second most common cause of heart failure in dogs is idiopathic dilated cardiomyopathy (iDCM), which results in heart failure or sudden cardiac death due to arrhythmia. This study aimed to determine changes in the plasma metabolome of dogs with iDCM compared to healthy dogs. For that purpose, a multiplatform mass-spectrometry-based approach was used. In this study, we included two groups of dogs: 12 dogs with iDCM and 8 healthy dogs. A total of 272 metabolites were detected in the plasma samples of dogs by combining three approaches but four MS-based platforms (GC-MS, LC-MS (untargeted), LC-MS (targeted), and FIA-MS (targeted) methods). Our findings demonstrated changes in the canine plasma metabolome involved in the development of iDCM, including the different concentrations of amino acids, biogenic amines, acylcarnitines, triglycerides and diglycerides, sphingomyelins, and organic acids. The results of this study will enable the detection and monitoring of pathophysiological mechanisms involved in the development of iDCM in the future.

Serum Proteomic Profiles Reflect the Stages of Myxomatous Mitral Valve Disease in Dogs.

Canine myxomatous mitral valve disease (MMVD) is similar to Barlow's form of MMVD in humans. These valvulopathies are complex, with varying speeds of progression. We hypothesized that the relative abundances of serum proteins would help identify the consecutive MMVD stages and discover new disease pathways on a systemic level. To identify distinction-contributing protein panels for disease onset and progression, we compared the proteomic profiles of serum from healthy dogs and dogs with different stages of naturally occurring MMVD. Dogs were divided into experimental groups on the basis of the left-atrium-to-aorta ratio and normalized left ventricular internal dimension in diastole values. Serum was collected from healthy (N = 12) dogs, dogs diagnosed with MMVD in stages B1 (N = 13) and B2 (N = 12) (asymptomatic), and dogs diagnosed with MMVD in chronic stage C (N = 13) (symptomatic). Serum biochemistry and selected ELISAs (galectin-3, suppression of tumorigenicity, and asymmetric dimethylarginine) were performed. Liquid chromatography-mass spectrometry (LC-MS), tandem mass tag (TMT) quantitative proteomics, and statistical and bioinformatics analysis were employed. Most of the 21 serum proteins with significantly different abundances between experimental groups (p < 0.05, FDR ˂ 0.05) were classified as matrix metalloproteinases, protease inhibitors, scaffold/adaptor proteins, complement components, anticoagulants, cytokine, and chaperone. LC-MS TMT proteomics results obtained for haptoglobin, clusterin, and peptidase D were further validated analytically. Canine MMVD stages, including, for the first time, asymptomatic B1 and B2 stages, were successfully distinguished in dogs with the disease and healthy dogs on the basis of the relative abundances of a panel of specific serum proteins. Most proteins with significantly different abundances were involved in immune and inflammatory pathways. Their role in structural remodeling and progression of canine MMVD must be further investigated. Further research is needed to confirm the resemblance/difference with human MMVD. Proteomics data are available via ProteomeXchange with the unique dataset identifier PXD038475.

Serum proteome profiling in canine chronic valve disease using a TMT-based quantitative proteomics approach.

Chronic valve disease (CVD) is the most common clinically significant heart disease of dogs, affecting 20 to 40% of dogs. The aim of this study was to evaluate the serum protein profile of healthy and CVD affected dogs, by means of an isobaric tandem mass tag (TMT) label-based high-resolution quantitative proteomic approach. Additionally, conventional cardiac biomarkers were measured in the serum, functional bioinformatics analysis was employed for elucidating molecular mechanisms and pathways associated with CVD, and validation of proteomic results was performed by immunoassays and Western blotting. Of 290 identified and quantified proteins, 15 proteins showed significantly different abundances (p < .05), including antithrombin-III, alpha-2-antiplasmin, tetranectin, apolipoprotein M, adiponectin, inter-alpha-trypsin inhibitor heavy chain H1, gelsolin and apolipoprotein B-100. The identified proteins with differently abundances are involved in a number of pathways, such as complement and coagulation cascades, haemostasis, regulation of actin cytoskeleton, lipid metabolism and transport. We found comparative similarities with human disease in terms of identified proteins and GO pathways, which confirmed similar pathophysiology of this disease, but also differences, mainly in lipid metabolism. SIGNIFICANCE: There have been few investigations of canine serum proteome despite the potential for biomarker discovery and comparative disease analysis. Establishing serum proteomic signatures in healthy dogs and dogs with CVD will benefit for understanding the aetiology of disease in dogs, identify putative biomarkers and provide models of comparative human disease. Circulating biomarkers are important for understanding of the mechanisms of cardiovascular disease and high incidence of CVD in dogs prioritizes the search for novel biomarkers.

Prevalence and Geographic Distribution of Vector-Borne Pathogens in Apparently Healthy Dogs in Croatia.

Vector-borne pathogens (VBPs) are a group of globally extended and quickly spreading pathogens that are transmitted by various arthropod vectors. The aim of the present study was to investigate the seroprevalence against Babesia canis, Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato, Leishmania infantum, Dirofilaria immitis, and Ehrlichia canis in dogs in Croatia. We investigated 435 randomly selected apparently healthy dogs in 13 different locations of Croatia for antibodies to B. canis by indirect immunofluorescence using a commercial IFA IgG Antibody Kit. All samples were also tested for qualitative detection of D. immitis antigen and for antibodies to A. phagocytophilum, B. burgdorferi sensu lato, L. infantum, and E. canis with two point-of-care assays. Overall, 112 dogs (25.74%, 95% confidence interval [CI] 21.70-30.12) were serologically positive for one or more of the pathogens. B. canis was the most prevalent pathogen (20.00%, 95% CI 16.34-24.07), followed by A. phagocytophilum (6.21%, 95% CI 4.12-8.90), L. infantum, (1.38%, 95% CI 0.51-2.97), and B. burgdorferi sensu lato (0.69%, 95% CI 0.01-2.00). The lowest seroprevalence was for D. immitis and E. canis (0.46%, 95% CI 0.01-1.65). Coinfection was determined in 12 dogs (2.76%, 95% CI 1.43-4.77), of which 10 were positive to two pathogens (7 with B. canis and A. phagocytophilum and 1 B. canis with B. burgdorferi sensu lato or L. infantum or E. canis). One dog was positive to three pathogens and another dog to four pathogens. Seroprevalence for babesia was age, breed, and lifestyle/use dependent. Purebred dogs had almost half the chance of developing disease than crossbred (OR = 0.58, p < 0.026, 95% CI 0.37-0.94). Seropositivity to B. canis was 3.41 times higher for dogs that lived outdoors/shelter (p < 0.006) or 4.57 times higher in mixed/hunting (p < 0.001) compared to indoor/companion dogs. This is the first comprehensive survey of VBP seropositivity conducted in Croatia. Some of these VBPs are zoonotic and represent a potential risk to public health.

Heart rate deflection point during incremental test in competitive agility border collies.

The aim of this study was to determine a heart rate deflection point (HRdp) in competitive agility dogs. Fourteen healthy border collies underwent progressive incremental treadmill exercise--modified Conconi test protocol. Heart rate was continuously recorded, and the HRdp was estimated using two methods: subjective and computer aided regression. Maximal heart rate (HRmax), achieved running speed at the anaerobic threshold and at the end of test were also determined. Statistical analysis showed a very high positive correlation between HRdp determined by two methods. The mean HRdp in this research corresponded to 80% of HRmax. The wide range of individual HRdp (162-229 BPM) indicates the need of an individual approach in assessing physiological parameters. To the authors' knowledge, this is the first application of Conconi modified test for estimating anaerobic threshold in agility dogs since the standard for dogs is yet undetermined. Future studies need to detect the most appropriate and reliable technique for its determination as well as its applicability in programming of the optimal training intensity.

Canine babesiosis in Europe: how many diseases?

Babesiosis, recognized since ancient times as an important disease of livestock and more recently as an emerging disease in dogs worldwide, is caused by intraerythrocytic protozoa of the genus Babesia and is transmitted by ticks. The pathophysiology of canine babesiosis has been extensively studied but many questions remain unanswered, especially regarding the diversity of disease manifestations in different European countries. Continued investigation of the similarities and differences in host-parasite interplay in canine babesiosis in different European countries should lead to a better understanding of the disease process, potentially leading to better prediction of disease outcome and the development of new treatment modalities. From the European point of view it is important to conduct these studies on Babesia canis.

Molecular evidence of natural infection with Babesia canis canis in Croatia.

The aim of the present study was to detect and characterise the species and subspecies of Babesia spp. that cause canine babesiosis in Croatia. Twenty-eight dogs with typical signs of babesiosis (lethargy, anorexia, fever, dark urine and thrombocytopenia) were included in this study. Their blood smears showed the presence of Babesia canis . The results showed the detection of one subspecies, namely Babesia canis canis using PCR, and subsequent sequence analysis demonstrated portions of the nss rRNA gene in 27 out of 28 samples. Sequence analysis of the isolates showed 100% identity in 11 samples, 99.7% identity (one nucleotide difference) in 11 samples and 99.4% identity (two nucleotides difference) in 5 samples with B. canis canis . The results of this study confirm the presence of B. canis canis in infected dogs in Croatia and demonstrate a slightly new genetic variant of Babesia subspecies.

Septic shock in canine babesiosis.

The records of all canine patients (86) that had been diagnosed with babesiosis and that were admitted to the Clinic for Internal Diseases, Faculty of Veterinary Medicine, Zagreb from January 2007 to December 2007 were reviewed retrospectively. All dogs that had been diagnosed with canine babesiosis and that had systemic inflammatory response syndrome (SIRS) followed by multiple organ dysfunction syndrome (MODS), and refractory hypotension, were included in this study. Of 86 patients diagnosed with canine babesiosis that were admitted during the study period, 10 had evidence of septic shock and were included in this study. Seven of the 10 dogs had a level of parasitaemia above 1%, with the highest level being 20.2%, seven of the 10 dogs were anaemic and three of the 10 dogs were leucopoenic. Thrombocytopenia was present in nine dogs. Hypoglycaemia was noted in two dogs, and bilirubinaemia in nine dogs. Four patients had involvement of two organs, five had involvement of three organs, and one had involvement of four organs. The organ that was most frequently involved was the kidney (nine cases). Central nervous system dysfunction was the rarest complication noted (one case). The mortality rate in non-septic shock canine babesiosis was 2.6%. All dogs that developed septic shock died between the first and the fourth day after admission. The 100% mortality rate that is reported here reflects the fact that in cases in which progression of the inflammatory response leads to the development of septic shock, an unfavourable outcome should be expected.