Abnormalities In Dogs Research Articles

Clinical and Diagnostic Findings in Dogs Infected with Trichuris vulpis: A Retrospective Study.

Trichuris vulpis is a parasite of the large intestine of canids and has a global distribution. Despite its well-established epidemiology, the question of its pathogenicity in dogs remains debated. It has been suggested that younger age and concurrent infection with Ancylostoma caninum may be responsible for more severe clinical presentations. This retrospective study aimed to describe the clinical and diagnostic features of T. vulpis-infected dogs and to compare these findings with dogs infected with both T. vulpis and other intestinal parasites (poly-infected dogs). Forty-five dogs were included, with twenty-five being solely infected by T. vulpis and twenty poly-infected dogs. Only weight loss was more frequent (p = 0.006) in poly-infected dogs compared to T. vulpis mono-infected dogs. No significant differences were observed in laboratory abnormalities between mono-infected and poly-infected dogs. Only diarrhea was more frequent (p = 0.007) in younger dogs compared to adults. The egg shedding pattern was significantly higher (p = 0.04) among adult dogs compared to young ones, and there was a significant positive correlation between egg shedding and age (r = 0.41; p = 0.005). These findings suggest that T. vulpis might be responsible for both clinical signs and laboratory abnormalities in dogs, irrespective of the host's age and the presence of other intestinal parasites.

Alterations of Myocardial Mitochondrial Morphology and Function in a Canine Model of Premature Ventricular Contractions-Induced Cardiomyopathy.

Changes in myocardial mitochondrial morphology and function in premature ventricular contractions (PVCs)-induced cardiomyopathy (PVCCM) remain poorly studied. Here, we investigated the effects of PVCs with different coupling intervals (CIs) on myocardial mitochondrial remodelling in a canine model of PVCCM. Twenty-one beagles underwent pacemaker implantation and were randomised into the sham (n = 7), short-coupled PVCs (SCP, n = 7), and long-coupled PVCs (LCP, n = 7) groups. Right ventricular (RV) apical bigeminy was produced for 12-week to induce PVCCM in the SCP (CI, 250 ms) and LCP (CI, 350 ms) groups. Echocardiography was performed at baseline and biweekly thereafter to evaluate cardiac function. Masson's trichrome staining measured ventricular interstitial fibrosis. The ultrastructural morphology of the myocardial mitochondria was analysed using transmission electron microscopy. Mitochondrial Ca2+ concentration, reactive oxygen species (ROS) levels, adenosine triphosphate (ATP) content, membrane potential, and electron transport chain (ETC) complex activity were measured to assess myocardial mitochondrial function. Twelve-week-PVCs led to left ventricular (LV) enlargement with systolic dysfunction, disrupted mitochondrial morphology, increased mitochondrial Ca2+ concentration and ROS levels, decreased mitochondrial ATP content and membrane potential, and impaired ETC complex activity in both the SCP and LCP groups (all p < 0.01 vs the sham group). Ventricular fibrosis was observed only in canines with LCP. Worse cardiac function and more pronounced abnormalities in mitochondrial morphology and function were observed in the LCP group than to the SCP group (all p < 0.05). We demonstrated myocardial mitochondrial abnormalities in dogs with PVCCM, characterised by abnormal mitochondrial morphology, mitochondrial Ca2+ overload, oxidative stress, and impaired mitochondrial energy metabolism. Compared to SCP, long-term LCP exposure resulted in more severe mitochondrial remodelling and cardiac dysfunction in dogs.

B- Mode Ultrasonography of Ocular Abnormalities in Dogs

Background: Ultrasonography is a simple, safe and non-invasive method to examine the internal structures of eye in case of opacity of otherwise clear ocular medium like cornea, aqueous, lens, and vitreous. Methods: 123 dogs with ocular abnormalities from March 2021 to October 2022, presented to the Division of Veterinary Surgery and Radiology were included in this study. All of the animals underwent a thorough ophthalmic examination along with B-scan ultrasonography of both the eyes using a 7.5 MHz linear probe. Result: Ultrasonography revealed thin hyperechoic lines and a thin hyperechoic rim of the lens, indicating early cataract changes and cortical cataract, respectively. Sixty-two dogs were found to be affected by cataract; 20 dogs were affected by the disease Phthisis bulbi; 16 dogs had a complete retinal detachment showing a typical “morning glory” sign; 10 dogs had vitreous haemorrhage; 6 dogs had a damaged eye with lens dislocation; and 5 dogs had choroidal melanoma and intraocular tumours in 4 dogs out of 123 observed dogs. Further, out of 62 cataract cases, 16 dogs were affected by cortical cataracts, 41 had nuclear cataracts, and 5 dogs were affected by morgagnian cataracts. Therefore, B-scan ultrasonography of the eye was a quick, safe, and accurate way to examine the pathology, especially when opaque media inhibit direct examination or when exophthalmos is evident and the normal anatomy of the eye.

Thromboelastographic results and hypercoagulability in dogs with surgically treated hepatocellular adenoma and carcinoma: A Veterinary Society of Surgical Oncology prospective study.

The most common haemostatic abnormality in dogs with cancer is hypercoagulability. A transient hypercoagulability has been documented in people with hepatocellular carcinoma (HCC) that resolves within weeks following hepatic tumour resection. The objective was to compare the haemostatic status of dogs with liver tumours and healthy control dogs, by comparing coagulation and thromboelastography (TEG) measurements at three time points. Liver tumour and healthy control dogs receiving surgery for liver lobectomy and ovariohysterectomy, respectively, were prospectively enrolled. All dogs had blood collected at three time points: pre-operative, 24 h post-operative and ~2 weeks post-operative. Haematological and haemostatic values were compared across time points in each group using repeated measures ANOVA tests. Ten and eight dogs were enrolled for the liver and control groups, respectively. Platelet count was significantly higher in the liver group than the control group at all time points, but within the normal range (pre-operative: 438.7 vs. 300.9 × 109 /L, p = .0078; 24 h post-operative: 416.2 vs. 283.9 × 109 /L, p = .0123; 10-14 days post-operative: 524.6 vs. 317.3 × 109 /L, p = .0072). The measure of the overall coagulant state (G-value) was significantly increased for the liver group compared to the control group at all time points (pre-operative: 15.6 vs. 8.6 d/sc, p = .0003; 24 h post-operative: 18.3 vs. 11.2 d/sc, p = .039; 10-14 days post-operative: 15.1 vs. 9.6 d/sc, p = .015). The liver group was hypercoagulable based on elevated G-values at all time points compared to the control group. This hypercoagulability was attributed to the effect of hepatic tumours alone, and not secondary to surgery and anaesthesia.

Causes of thrombocytopenia in dogs in the United Kingdom: A retrospective study of 762 cases.

Thrombocytopenia is a common laboratory abnormality in dogs, and numerous diseases have been associated with its development. Estimates for the sensitivity and specificity of the degree of reduction of platelet concentration for the diagnosis of primary immune-mediated thrombocytopenia (pITP) have not been reported. To report the prevalence of different causes of thrombocytopenia in dogs in the United Kingdom and to investigate the utility of platelet concentration to differentiate causes of thrombocytopenia. Medical records of 762 dogs with thrombocytopenia presented to seven referral hospitals from January 2017 to December 2018 were retrospectively reviewed. Cases were assigned into the following categories: pITP, infectious diseases, neoplasia, inflammatory/other immune-mediated disorders and miscellaneous causes. The prevalence of the different categories was estimated, and platelet concentrations were compared. Receiver-operating characteristic (ROC) curves were used to investigate the utility of platelet concentration to differentiate between causes of thrombocytopenia. The most common disease category associated with thrombocytopenia was neoplasia (27.3%), followed by miscellaneous causes (26.9%), pITP (18.8%), inflammatory/immune-mediated disorders (14.4%) and infectious diseases (12.6%). Dogs with pITP had significantly lower platelet concentrations (median 8×109 /L, range: 0-70×109 /L) than dogs in the other four categories. Platelet concentration was useful for distinguishing pITP from other causes of thrombocytopenia (area under ROC curve=0.89, 95% confidence interval 0.87, 0.92), with a platelet concentration ≤12×109 /L being 60% sensitive and 90% specific. Severe thrombocytopenia was highly specific for a diagnosis of pITP, which was more prevalent in this UK population of thrombocytopenic dogs compared with previous epidemiological studies. Conversely, the proportion of dogs with infectious diseases was lower than in previous reports from other locations.

Coagulation Abnormalities in Dogs with Parvoviral Enteritis.

Hemostatic alterations have been documented in dogs with canine parvoviral enteritis. This study's aims were to measure the standard coagulation parameters, and to assess the relationship between them and the clinical variables in dogs with canine parvoviral enteritis. Nine client-owned dogs with a canine parvoviral infection were included in a prospective, observational clinical study. Clinical score and coagulation status were assessed at admission. All nine dogs showed alterations of three or more standard coagulation variables. A correlation analysis evidenced a significantly high positive correlation between the activated partial thromboplastin time and clinical score. The present study concurs that dogs with canine parvoviral enteritis have coagulation disorders that are detectable by measuring the standard coagulation parameters.

Investigating hypercalcaemia in cats and dogs

Background: Hypercalcaemia is an important biochemical abnormality in dogs and cats and can lead to a wide variety of clinical signs, including polyuria, polydipsia and vomiting. It can be caused by several diseases of which the prognoses are variable. Both dogs and cats should undergo appropriate investigations, and cat owners in particular must be prepared for likely extensive investigation, excluding all known aetiologies, before a potential diagnosis of idiopathic hypercalcaemia. Understanding calcium physiology and pathophysiology can help both the general practitioner and referral practitioner streamline their investigation and achieve a rapid diagnosis. Hypercalcaemia has a well‐defined list of differential diagnoses and methodical investigation will allow the clinician to optimise patient outcome.Aim of the article: This article describes a stepwise approach to the investigation of patients with ionised hypercalcaemia, and highlights some of the key differences between dogs and cats.

Diagnostic utility of two-dimensional shear wave elastography in nephropathic dogs and its correlation with renal contrast-enhanced ultrasound in course of acute kidney injury.

Aims of our study were to evaluate the feasibility and diagnostic value of two-dimensional shear wave elastography in dogs with acute kidney injury, chronic kidney disease, and acute on chronic kidney disease, its correlation with renal functional (creatinine, urea), and prognostic parameters (serum calcium-phosphorus product, urinary output), and with contrast-enhanced ultrasound (qualitative and quantitative evaluation). The study was prospective. A group of healthy (Group A) and a group of nephropathic dogs (Group B) were included. Shear wave elastography was performed on the left kidney of the subjects of both groups; contrast-enhanced ultrasound was performed only in dogs with acute kidney injury and acute on chronic kidney disease. Sixty-four dogs were included (Group A, n=24; Group B, n=40). The renal stiffness values were significantly higher in Group B than Group A; optimal cut-off stiffness values for detection of renal pathology were: ≥1.51 m/sec (area under the curve, 0.84; 95% confidence interval 0.74-0.94) and ≥6.75 kPa (area under the curve, 0.84; 95% confidence interval 0.73-0.94). For contrast-enhanced ultrasound, a significant positive correlation was found between renal stiffness, area under the curve, and wash-out area under the curve values of cortex quantitative analysis. No correlations were found between renal stiffness and renal functional and prognostic parameters. Shear wave elastography showed diagnostic utility to detect renal abnormalities in dogs with acute kidney injury, chronic kidney disease and acute on chronic kidney disease, however, it could not differentiate between these different nephropathies.

Bimod Vet®, a medical device for early and fast detection of cardiac abnormalities in dogs: Experimental validation and first results on heart rhythm

This article presents a new intelligent, mobile, and connected medical device: Bimod Vet®. Fast and noninvasive, it enables an early detection of some dog's cardiac abnormalities, as arrhythmias and murmurs, in less than 60 seconds and in normal examination conditions, without hair shaving, wireless, without clamps or sticky electrodes and without immobilization. It combines 2 essential signals in cardiology, keeping their natural synchronicity: electrocardiogram and phonocardiogram. Recordings were obtained in 44 dogs from 30 different breeds, with age ranging from 2,5 months to 19 years and weight from 2 kg to 36 kg, in thin and obese individuals with different types of hair, in healthy animals or dogs presenting with different cardiac diseases. Very satisfying results were achieved: the device has many experimental assets to perform a cardiac examination on a dog with no stress induced, by easy and fast recording in every type of dog and enabling to precisely measure the heart rate and to detect rhythm disorders from good quality electrocardiograms, according to age and weight of dogs. Cet article introduit un nouveau dispositif médical intelligent, mobile et connecté : Bimod Vet®. Rapide et non invasif, il permet la détection précoce de certaines anomalies cardiaques chez les chiens, comme les arythmies et les souffles, en moins de 60 secondes et dans des conditions d’examen normales, sans tonte, fils, pinces ou électrodes adhésives ni immobilisation de l’animal. Il combine 2 signaux cardiaques essentiels, en conservant leur synchronicité naturelle : l’électrocardiogramme et le phonocardiogramme. Des essais ont porté sur 44 chiens de 30 races différentes, âgés entre 2,5 mois et 19 ans, de poids compris entre 2 kg et 36 kg, avec état d’embonpoint variable, pelages différents, sains ou présentant différentes maladies cardiaques. Nous avons obtenu des résultats très satisfaisants : le dispositif est adapté à la réalisation d’un enregistrement sur un chien (non stressant, simple, rapide et fonctionnel pour tout type de chiens) et détecte de manière fiable la fréquence cardiaque et les troubles du rythme, en fonction de l’âge et du poids, à partir d’électrocardiogrammes de très bonne qualité.

Red fox (Vulpes vulpes) play an important role in the propagation of tick-borne pathogens

The red fox (Vulpes vulpes) is the most widespread free-living carnivore in the world. Over the years, foxes have been recognized as hosts for a number of tick-borne pathogens. However, their role as reservoirs for zoonotic tick-borne diseases is poorly understood. The aim of our study was to investigate tick-borne pathogens in the red fox population in the Czech Republic. Out of 117 red foxes, 110 (94.02%) individuals tested positive for the presence of at least one pathogen by the combined PCR and sequencing approach. Hepatozoon canis was the most frequently detected pathogen (n = 95; 81.2%), followed by Babesia vulpes (n = 75; 64.1%). Babesia canis was not detected in our study. Four (3.42%) red foxes were positive for Candidatus Neoehrlichia sp., 3 (2.56%) for Anaplasma phagocytophilum, and one red fox (0.85%) tested positive for the presence of Ehrlichia sp. DNA. Overall, DNA of spirochetes from the Borrelia burgdorferi s.l. complex was detected in 8.6% of the foxes and B. miyamotoi in 5.12% of the samples. As a carnivore found in all ecosystems of Central Europe, foxes obviously contribute to transmission of tick-borne pathogens such as A. phagocytophilum, B. burgdorferi s.l., and B. myiamotoi. In addition, foxes apparently harbour a community of pathogens, associated with this host in local ecological context, dominated by H. canis and B. vulpes (possibly also Candidatus Neoehrlichia sp.). These species have the potential to spread to the domestic dog population and should be included in the differential diagnosis of febrile diseases with hematologic abnormalities in dogs.

Metabolic changes associated with two endocrine abnormalities in dogs: elevated fructosamine and low thyroxine

IntroductionMetabolomics studies in canine endocrine abnormalities are sparse and basic information on these abnormalities must be generated.ObjectivesTo characterize the metabolic changes associated with elevated fructosamine, reflecting poor glycemic control, and low thyroxine, a thyroid hormone controlling metabolism.MethodsLeftovers of clinical serum samples; 25 controls, 79 high fructosamine, and 47 low thyroxine, were analyzed using 1H NMR and differences were evaluated using Firth logistic regression.ResultsBoth high fructosamine and low thyroxine were associated with changes in concentrations of multiple metabolites, including glycoprotein acetyls and lipids.ConclusionThese findings suggest promising makers for further research and clinical validation.

Cystoscopic Abnormalities in Dogs Presented for Episioplasty.

A recessed vulva is a conformational abnormality that predisposes affected dogs to urinary tract infections. An episioplasty can be recommended for correction of this abnormality when medical management of recurrent urinary tract infection fails. The objective of this study was to investigate the type and incidence of urogenital abnormalities visualized by cystoscopy in dogs presenting for episioplasty. Medical records of 29 dogs that presented for an episioplasty and had a concurrent or prior cystoscopy were reviewed. Eleven of the 29 dogs had urogenital abnormalities diagnosed on cystoscopic evaluation, and 1 dog was diagnosed with a urogenital abnormality during vaginal examination while under general anesthesia. Ten of the dogs with urogenital abnormalities had a corrective procedure performed, 8 of which were cystoscopically assisted. Cystoscopy provides the ability to directly visualize the urinary tract and obtain samples for biopsy and culture and facilitates correction of some anatomic abnormalities that may predispose the patient to developing recurrent urinary tract infections. Cystoscopy should be considered as a routine part of a thorough evaluation of the urinary tract in cases presenting for episioplasty.

Serum protein electrophoresis in Dirofilaria immitis naturally infected dogs: Latest news and a systematic literature review

According to the main Guidelines on canine heartworm disease (HWD) by the American and European Societies (i.e., AHS, ESDA, and ESCCAP), a correct diagnosis of Dirofilaria immitis infection should include the detection of circulating microfilariae in the whole blood and the adult antigens in serum or plasma sample. So far, scant data are available on laboratory abnormalities in dogs affected by HWD, although techniques including serum protein electrophoresis (SPEP) have proved to be useful for the diagnosis and monitoring of other vector-borne diseases, such as the canine leishmaniosis. Therefore, this study aims to evaluate the SPEP pattern in dogs naturally infected by D. immitis. Furthermore, a systematic review of the literature on this topic was carried out. Medical records from heartworm-positive dogs, of any sex, age, and breed and with available clinical examination and laboratory test results (i.e., complete blood count, serum biochemical profile, and SPEP) were retrospectively collected. If available, laboratory results obtained from dogs after treatment for HWD were also evaluated. When compared with the reference intervals, out of 30 dogs infected by D. immitis and enrolled, 63.3% (n = 19) had a lower percentage of albumin, and 80.0% (n = 24) had higher percentages of beta globulins, with beta-2, and especially beta-3 globulins the most frequently altered fractions. In terms of absolute values (g/dL), the proportion of dogs with hypoalbuminemia, and increased total globulin, alpha, beta- and gamma globulins were 4/30 (13.3%), 6/30 (20.0%), 2/30 (6.7%), 16/30 (53.3%) and 8/30 (26.7%), respectively. For 7 dogs, SPEP results evaluated three and six months after treatment with doxycycline (10 mg/kg BID for 4 weeks) were available. In these dogs a significant post-treatment increase in the percentage of albumin, alpha-2 globulin, and albumin/globulins ratio was observed, as well as a significant decrease both in the percentage and in the absolute value of total-, beta-, and beta-3 globulins. The systematic review of literature databases yielded a total of three studies that were considered eligible and included in the qualitative synthesis. This study provides novel information on SPEP alterations in dogs naturally infected by D. immitis. The evaluation of serum proteins and their electrophoretic pattern may represent an important diagnostic tool for a prompt and accurate diagnosis (e.g., differentiating infections in dogs sharing similar clinical signs and endemic in the same geographical area) and monitoring of HWD.

Metabolomic serum abnormalities in dogs with hepatopathies

Hepatopathies can cause major metabolic abnormalities in humans and animals. This study examined differences in serum metabolomic parameters and patterns in left-over serum samples from dogs with either congenital portosystemic shunts (cPSS, n = 24) or high serum liver enzyme activities (HLEA, n = 25) compared to control dogs (n = 64). A validated targeted proton nuclear magnetic resonance spectroscopy platform was used to assess 123 parameters. Principal component analysis of the serum metabolome demonstrated distinct clustering among individuals in each group, with the cluster of HLEA being broader compared to the other groups, presumably due to the wider spectrum of hepatic diseases represented in these samples. While younger and older adult control dogs had very similar metabolomic patterns and clusters, there were changes in many metabolites in the hepatopathy groups. Higher phenylalanine and tyrosine concentrations, lower branched-chained amino acids (BCAAs) concentrations, and altered fatty acid parameters were seen in cPSS dogs compared to controls. In contrast, dogs with HLEA had increased concentrations of BCAAs, phenylalanine, and various lipoproteins. Machine learning based solely on the metabolomics data showed excellent group classification, potentially identifying a novel tool to differentiate hepatopathies. The observed changes in metabolic parameters could provide invaluable insight into the pathophysiology, diagnosis, and prognosis of hepatopathies.

Red blood cell abnormalities occur in dogs with congenital ventricular outflow tract obstruction.

To document RBC abnormalities in dogs with congenital ventricular outflow tract obstruction. 62 dogs with pulmonic stenosis (PS) or aortic stenosis (AS) and 20 control dogs were recruited. The proportions of RBCs that were schistocytes, acanthocytes, and keratocytes were assessed. Complete blood cell counts were performed. Tested variables included hemoglobin concentration, hematocrit, and erythrocyte count. Median (interquartile range [IQR]) peak systolic Doppler-derived trans-stenotic pressure gradient (∆P) values were 161 mm Hg (108 to 215 mm Hg) and 134 mm Hg (125 to 165 mm Hg) for dogs with PS and AS, respectively. Hematologic abnormalities were detected in most dogs with AS or PS (54/62 [87%]) versus 8/20 [40%] in control dogs, with schistocytes found in 40 of 62 (65%; median, 0.1% RBCs; IQR, 0% to 0.3%), acanthocytes in 29 of 62 (47%; median, 0.3% RBCs; IQR, 0% to 0.9%), keratocytes in 39 of 62 (63%; median, 0% RBCs; IQR, 0% to 0.2%), and hemolytic anemia in 4 dogs with PS. No significant association was identified between these abnormalities and ∆P. However, 3 of 4 dogs with anemia had a ∆P > 200 mm Hg (range, 242 to 340 mm Hg). The dog with the highest ∆P value also had the most severe anemia and schistocytosis, and both resolved after balloon valvuloplasty. Poikilocytosis is common in dogs with congenital ventricular outflow tract obstruction, with anemia only observed in few dogs with high ∆P values.

Assessment of iris vasculature abnormalities in dogs with diabetes mellitus.

To identify and characterize abnormalities of iris vasculature in dogs with diabetes mellitus, compared to clinically normal, age-matched control dogs, by means of anterior segment angiography. 10 dogs with naturally occurring diabetes mellitus and 10 age-matched control dogs with no ocular or systemic disease. The day before iris vasculature abnormality (IVA) assessment, all dogs underwent complete physical and ophthalmic examinations and baseline clinicopathologic analyses. For diabetic dogs, serum fructosamine concentration and a 12-hour blood glucose concentration curve were generated. The next day, all dogs were sedated and anterior segment angiography (following IV injection of indocyanine green [1 mg/kg] and subsequently sodium fluorescein [20 mg/kg]) was performed with a full-spectrum camera and camera adapter system. Group findings were compared, and multiple linear regression analysis was performed to identify potential factor associations with IVAs. During anterior segment angiography, the arterial, capillary, and venous phases were identified in all dogs. Times to onset of all phases in diabetic dogs were significantly less than those in control dogs. Vascular disruptions within the peripupillary region (evident following sodium fluorescein administration) were common in diabetic dogs. Severity of dye leakage into the iris stroma and aqueous humor was significantly greater in diabetic dogs than in control dogs. Duration of disease, mean blood glucose concentration, and serum fructosamine concentration were significantly associated with IVAs. In diabetic dogs, anterior segment angiography revealed IVAs that were not evident in control dogs. The severity of those changes appeared to be associated with disease duration and blood glucose regulation.

Chromosome abnormalities in dogs with disorders of sex development (DSD)

Disorders of sex development (DSD) caused by chromosome abnormalities are rarely diagnosed in dogs. In this report, there is a focus on five DSD cases in which the dogs had abnormal karyotypes. All animals were recognized by owners as females, however, these dogs had a large number of reproductive defects. Among these were abnormal external genitalia such as an enlarged clitoris, abnormal development of the labia, abnormal location of the vulva and urethral orifice, and other abnormalities were observed in four dogs. Gonadal histology assessments were conducted on three dogs and there were diagnoses of the presence of an ovary, inactive testes, and ovotestis with calcification in ovarian follicles. Results from cytogenetic analysis indicated there were the following karyotypes: (a) X trisomy in a mosaic form (79,XXX/78,XX); (b) Robertsonian translocation in a mosaic form (77,XX,rob/78,XX); (c) nonmosaic X/autosome translocation (78,X,t(X;A)); (d) X/autosome translocation in a mosaic form (78,X,t(X;A)/78,XX); and (e) leukocyte chimerism (78,XX/78,XY). The findings in the present study, emphasize that cytogenetic analysis is essential for elucidating the pathogenesis of DSD in dogs.

Clinical Cytogenetics of the Dog: A Review.

Simple SummaryThe cytogenetic analysis of dogs is mainly focused on the diagnosis of disorders of sex development (DSD) and cancers. Unfortunately, the study of canine chromosomes is a challenging task due a high chromosome number (2n = 78) and the one-arm morphology of all autosomes. For years, the application of conventional cytogenetic techniques, Giemsa staining and G and DAPI (4′,6-diamidino-2-phenylindole) bandings, allowed the identification of sex chromosome aneuploidies and centric fusions. An advanced clinical cytogenetic diagnosis is also needed due to the fact that the dog is a valuable animal model in biomedical research. The application of hybridization methods, such as fluorescence in situ hybridization (FISH) and array comparative genome hybridization (aCGH), facilitated the detection of other chromosomal rearrangements. It can be foreseen that a wide use of modern molecular techniques (e.g., SNP microarray and next generation sequencing) will substantially extend the knowledge on canine chromosome mutations.The dog is an important companion animal and has been recognized as a model in biomedical research. Its karyotype is characterized by a high chromosome number (2n = 78) and by the presence of one-arm autosomes, which are mostly small in size. This makes the dog a difficult subject for cytogenetic studies. However, there are some chromosome abnormalities that can be easily identified, such as sex chromosome aneuploidies, XX/XY leukocyte chimerism, and centric fusions (Robertsonian translocations). Fluorescence in situ hybridization (FISH) with the use of whole-chromosome painting or locus-specific probes has improved our ability to identify and characterize chromosomal abnormalities, including reciprocal translocations. The evaluation of sex chromosome complement is an important diagnostic step in dogs with disorders of sex development (DSD). In such cases, FISH can detect the copy number variants (CNVs) associated with the DSD phenotype. Since cancers are frequently diagnosed in dogs, cytogenetic evaluation of tumors has also been undertaken and specific chromosome mutations for some cancers have been reported. However, the study of meiotic, gamete, and embryo chromosomes is not very advanced. Knowledge of canine genome organization and new molecular tools, such as aCGH (array comparative genome hybridization), SNP (single nucleotide polymorphism) microarray, and ddPCR (droplet digital PCR) allow the identification of chromosomal rearrangements. It is anticipated that the comprehensive use of chromosome banding, FISH, and molecular techniques will substantially improve the diagnosis of chromosome abnormalities in dogs.

Long-term administration of prednisolone: Effects on the myocardial tissue of healthy beagle dogs.

This study aimed to assess the structural and functional effects of long-term hyperglucocorticoidemia on canine myocardium and compare these parameters with histopathological changes. Twelve healthy male beagle dogs were enrolled and assigned to the high-dose prednisolone (P; n=6) and control (C; n=6) groups. The P group was treated with 2 mg/kg of prednisolone BID for 84 days. Clinical parameters were measured using echocardiography and non-invasive systolic blood pressure (SBP) measured before the initiation of synthetic corticosteroids and at 7, 28, 56, and 84 days after the start of medication. For histological evaluation, cardiovascular tissue was harvested from dogs in groups P (at the end of the medication period) and C (scheduled to be euthanized for unrelated reasons). In the P group, clinical changes including thickening of the left ventricular free wall (LVFW) and interventricular septum (IVS), decreased left ventricular (LV) diastolic function, and increased SBP were observed after the start of medication. During histological evaluation, fibrosis was observed in the LVFW and IVS in the P group. Furthermore, decreased glucocorticoid receptor (GCR) levels were observed in the LVFW, right ventricular free wall (RVFW), and IVS and increased mineralocorticoid receptor (MCR) levels were observed in the LVFW and RVFW in the P group compared with those in the C group. In conclusion, fibrosis may cause LV structural and functional abnormalities in dogs with hyperadrenocorticism. Furthermore, GCR downregulation and upregulated MCR might influence the myocardial fibrosis.

Diagnosis and treatment of gastro-oesophageal junction abnormalities in dogs with brachycephalic syndrome.

To determine whether there is a benefit of using pre- and postoperative antacid treatment in dogs undergoing surgery for brachycephalic syndrome. To assess the use of an obstruction manoeuvre during endoscopy for the detection of dynamic gastro-oesophageal junction abnormalities. Thirty-six client-owned brachycephalic dogs were prospectively included in a randomised trial. Antacid treatment was randomly prescribed in 18 dogs before and after surgery while the other 18 dogs did not receive any gastrointestinal medical treatment. At presentation, at the time of surgery and at recheck, digestive clinical signs and gastro-oesophageal junction abnormalities were assessed using specific scores. Gastro-oesophageal junction abnormalities were assessed during endoscopy in standard conditions as well as during endotracheal tube obstruction. This manoeuvre was also applied in an unrelated control group. The results suggest a beneficial effect of antacid treatment on the improvement of digestive clinical signs and lesions in dogs with brachycephalic syndrome undergoing surgery. At postsurgical control 83% of dogs had a digestive clinical score ≤1 in the treated group in contrast to 44% in the non-treated group and 39% of dogs had a gastro-oesophageal abnormalities score (during obstruction manoeuvre) ≤1 in the treated group in contrast to 16.7% in the non-treated group. The use of the obstruction manoeuvre during endoscopic assessment in a control group revealed that gastro-oesophageal junction movements are negligible in healthy animals. The addition of antacid treatment during the pre- and postoperative period for brachycephalic dogs undergoing surgery may result in a faster and greater improvement in treated dogs. The obstruction manoeuvre is an interesting technique to improve detection of gastro-oesophageal junction abnormalities.