QT interval instability and QRS interval dispersion in healthy cats and cats with a hypertrophic cardiomyopathy phenotype.

OBJECTIVES: Hypertrophic cardiomyopathy (HCM) is the most common heart disease in cats. Electrocardiographic (ECG) analysis can help with the diagnosis of HCM and also in the investigation of the secondary consequences of the disease. This study investigated ECG markers of QT interval variability (total instability [TI], short-term instability [STI], long-term instability [LTI], QT variance [QTv]), mean QT interval (QTa) and QT interval corrected for heart rate (QTac), as well as the duration (QRSd) and dispersion (QRSv) of the QRS interval in healthy cats and in those with HCM. METHODS: Data were collected from 63 domestic cats: 40 in the control group and 23 in the HCM group. Fifty consecutive QT intervals were recorded for all cats and then QTa, QTac, QTv, TI, LTI and STI were calculated. QRSd and QRSv were also obtained for all animals. A Mann-Whitney U-test was used for group comparison. Receiver operating characteristic curves were plotted to evaluate the sensitivity and specificity of all markers for HCM. Logistic regression analysis was performed to assess the risks of cats having HCM, based on the studied indexes. RESULTS: QTa (P <0.01), QTac (P <0.01), QRSd (P <0.01) and STI (P = 0.02) were higher in the HCM group. QTa >158.8 ms, QTac >27.4 ms and QRSd >0.045 s had an accuracy of 77.4%, 68.2% and 80.9%, respectively, in detecting HCM. Logistic regression showed that cats with QTa >158 ms, QTac >27.4 ms and QRSd >0.045 s had a 1.58-, 1,23- and 6.5-fold higher risk, respectively, of developing HCM. CONCLUSIONS AND RELEVANCE: Cats with HCM had higher ventricular instability as assessed by STI and showed a prolongation of the QT and QRS intervals via the QTa, QTac and QRSd markers. These markers show potential as ancillary screening tools for identifying the presence of HCM.

Tpeak-Tend, a novel electrocardiographic marker in cats with hypertrophic cardiomyopathy-a brief communication.

Hypertrophic cardiomyopathy (HCM) is the most common heart disease in feline species. ECG allows assessing parameters that can help in the diagnosis and risk stratification of conditions that occur secondary to this disease. This study aimed to evaluate electrocardiographic markers Tpte and Tpte/QT in leads I, II, III, aVR, aVL and aVF in control and HCM cats. Data were obtained from 63 domestic cats allocated in a Control (n = 40) and an HCM (n = 23) group. Tpte and Tpte/QT of all individuals were measured in all limb leads (I, II, III, aVR, aVL, aVF). We constructed ROC curves to evaluate the sensitivity and specificity of markers to identify HCM-affected cats. Logistic regression analysis was performed to assess the risks of cats having HCM based on Tpte indexes. Tpte in leads II (p < 0.01), aVR (p < 0.01), aVL (p < 0.01), and aVF (p < 0.01) had significantly higher results in the HCM group. Tpte/QT showed no statistical difference between groups in any of the derivations evaluated. A Tpte > 27.5ms in lead aVF showed an accuracy of 83.3% to identify individuals with HCM in our study. Univariable logistic regression reveals that cats with Tpte in aVR and aVF > 27.5ms and in aVL > 26.5ms had 1.28, 12 and 1.16 respectively, more chances of having HCM. The prolongation of Tpte may be a noninvasive electrocardiographic complementary tool to help differentiate patients with and without hypertrophic cardiomyopathy.

Role of echocardiographic views adapted for lung evaluation in diagnosis of cardiogenic pulmonary edema in Dogs.

The objective of this study was to determine whether echocardiographic views adapted for lung evaluation may aid in diagnosis of dyspnea in dogs. Fifteen chronic valvular heart disease (CVHD) dogs without cardiac remodeling, 30 CVHD dogs with cardiac remodeling, 15 CVHD dogs with cardiogenic pulmonary edema and 15 dogs with pulmonary disease were prospectively enrolled. Loop recordings of pericardial-lung ultrasound were gathered during echocardiographic evaluation, and four videos of 4 different adapted views were recorded for each dog. Chest X-rays were used as reference-standard for pulmonary edema and/or disease. The videos were classified based on the number of B- lines as NEGATIVE (0, 1, 2 or 3) or POSITIVE (> 3 or confluent). Accuracy of a POSITIVE classification in identifying pulmonary edema and/or disease was calculated. Multivariate analyses were performed using echocardiographic variables that reflect increased left ventricular filling pressure (LVFP) to distinguish pulmonary edema from disease. Results showed that a POSITIVE classification distinguished dogs with pulmonary edema or disease from asymptomatic CVHD dogs in all four views. The best views were right parasternal short axis at papillary muscle level and long axis 4- chamber view, both with the same sensitivity (86.7%) and a specificity of 95.6% and 82.2%, respectively. Multivariate analyses showed that adding cutoff values of peak E wave > 130, E/IVRT > 2.5 or LA/Ao > 2.0 distinguished pulmonary edema from disease with 100% specificity. In conclusion, echocardiographic views adapted for lung evaluation, in addition to conventional echocardiography, may help identify the cause of dyspnea in dogs.

QT interval instability and variability in dogs with naturally-occurring hypercortisolism.

Hypercortisolism is one of the most common endocrine diseases in dogs. In humans, it is clearly associated with a higher risk of cardiovascular events, but studies in dogs are scarce. To investigate the arrhythmogenic risk of dogs with naturally-occurring hypercortisolism (NOHC), indices of variability and instability of the QT interval were retrospectively studied in 38 dogs with NOHC and prospectively studied in 12 healthy dogs: variance (QTv), total instability (TI), short-term (STI) and long-term (LTI), and mean (QTm). Except for QTm, all parameters studied were higher in the NOHC group than in the control group. In addition, STI and QTv showed moderate positive correlation with left ventricle wall thickness. The NOHC group was subdivided according to cortisol suppression pattern in the low-dose dexamethasone suppression test. All electrocardiographic indices of partial and absent suppression patterns were numerically higher than healthy dogs. QTv and TI were lower in the control group than in both NOHC subgroups. LTI and STI were lower in the CG than in the group with the partial suppression pattern. There was no statistical difference between sex groups in any of the electrocardiographic parameters studied. This result might indicate that the etiology of NOHC, and its consequent influence on hypothalamus-pituitary-adrenal axis could interfere on the heterogeneity of ventricular repolarization parameters in different ways, especially in the short-term and the long-term stability; however further studies are necessary to understand the role of cortisol on electrical instability in dogs.

Timolol 0.5% ophthalmic solution influences cardiac function in healthy cats.

OBJECTIVES: The aim of this study was to ascertain the effect of a drop of timolol 0.5% ophthalmic solution on the systolic function of the left ventricle (LV) and left atrium (LA), and to confirm if timolol helped appraisal of diastolic function by reducing heart rate (HR) and separating the transmitral outflow waves from tissue Doppler imaging (TDI). METHODS: A total of 41 client-owned healthy cats underwent two echocardiograms 20 mins apart. The timolol group (33 cats) received a drop of timolol solution after the first examination. Standard and speckle-tracking echocardiography evaluated the LV and LA function of both groups at the two time points evaluated. RESULTS: Timolol reduced HR (19%), and fractional shortening from LV (20.3%) and LA (16.6%). Septal S' decreased by 51% (from 7.7 to 5.2 cm/s) and lateral S' dropped by 43.1% (7.3 to 5.1 cm/s). Most longitudinal techniques did not change after timolol, including the mitral annular plane systolic excursion from the interventricular annulus, tricuspid annular plane systolic excursion, LV longitudinal strain and LV tissue motion annular displacement. The isovolumic relaxation time increased by 15.2% (from 54 to 64.6 ms), with most cats presenting this variable above the reference (>60 ms). Timolol did not support diastolic assessment, enabling evaluation in only 2/11 cats when using lateral TDI and 1/9 cats using septal TDI. Regarding side effects, miosis occurred in 18 cats (54.5%). CONCLUSIONS AND RELEVANCE: Timolol reduced systolic function, decreasing standard echocardiographic variables. Regarding diastolic evaluation, although timolol decreased HR, it did not separate the mitral diastolic waves, as expected.

Tissue motion annular displacement to assess the left ventricular systolic function in healthy cats.

The tissue motion annular displacement (TMAD) measures the longitudinal displacement of the mitral annulus during systole, using speckle-tracking echocardiography (STE). The main objective was to determine the TMAD means in healthy cats, exploring the correlations with systolic surrogates. The influence of age, body surface area (BSA), heart rate, and systemic blood pressure on the indices was also analyzed. One hundred ninety-three healthy, client-owned cats participated in this prospective, cross-sectional observational study undergoing conventional and STE. Apical four-chamber (AP4) and two-chamber (AP2) images were recorded for offline calculations. Mean TMAD values were similar to mitral annulus plane systolic excursion (MAPSE), varying between 4 to 4.8 mm depending on the annulus and image used. No significant differences between age and BSA categories were detected, except for AP4 MP%, reduced in the heavier group. TMAD variables showed moderate correlation with longitudinal strain (LSt) and MAPSE, but not with fraction shortening (FS) and ejection fraction (EF). The median time required for the offline calculation was 12.2 s for AP4 and 11.8 s for AP2. The technique showed moderate inter and intraobserver variation, proving a reliable tool for assessing left ventricular longitudinal systolic function in cats.

TRANSTHORACIC ECHOCARDIOGRAPHY IN NONSEDATED, FREE-RANGING HEALTHY AGOUTIS (DASYPROCTA AZARAE).

Most of the agouti species are kept in captivity, including the species Dasyprocta azarae. These animals are of zootechnical interest and, in addition, they can potentially be used as experimentation models because of their physical characteristics and possibility of manipulation. Therefore, the purpose of this study was to investigate the feasibility of the echocardiographic exam in nonsedated agoutis and to determine the normal reference ranges for the standard transthoracic echocardiographic parameters in healthy, adult, free-ranging agoutis found in an urban wood and intended for scientific investigations. Most of the echocardiographic parameters evaluated were similar to what has already been described for other rodent species such as rabbits or the Dasyprocta primnolopha agoutis. Based on the information compiled in this study, echocardiographic examination is feasible in awake adult, free-ranging agoutis. The results obtained from the morphologic and hemodynamic evaluation of the heart can help in future studies, either involving the clinical aspects or considering the potential use of these animals as an experimental model.

Characterization of Doppler spectrum of hepatic veins and correlation with structural and functional variables of the right ventricle in healthy dogs.

BACKGROUND: Spectral Doppler assessment of hepatic veins may provide information on heart function. HYPOTHESIS/OBJECTIVES: To assess the normal pattern of hepatic venous flow using spectral Doppler ultrasound examination; to correlate this information with structural and functional variables of the right ventricle (RV), and to analyze the impact of age, sex, body weight quartiles, heart rate, cardiac rhythm, and systolic arterial pressure on the results in healthy dogs. ANIMALS: Sixty-five healthy dogs. METHODS: Cross-sectional observational study. The direction and maximum velocity of each of the 4 possible components of venous flow were determined from pulsed-wave Doppler examination of the hepatic veins. In addition, structural and functional parameters (TAPSE, longitudinal strain, FAC%, S', Et /At, and E't / A't ) of the RV were evaluated. RESULTS: The same phase patterns for different waves were seen in all animals: A and V were retrograde waves, and S and D were anterograde waves. The velocity of the spectral waves increased with body weight (P < .05) and could be correlated with functional indices of the RV. A significant difference was found when comparing morphometric indices with body weight quartiles (P < .05). In addition, intra-and inter-observer assessments showed low variability. The mean duration of the examinations was 5.2 minutes. CONCLUSIONS AND CLINICAL IMPORTANCE: Hepatic spectral Doppler findings can be correlated with systolic and diastolic indices of the RV and vary with body weight.

Polymorphism, coupling interval and prematurity index in dogs with degenerative mitral valve disease and ventricular arrhythmias.

Ventricular arrhythmias (VA) are a recognized concern in dogs with degenerative mitral valve disease (DMVD). The coupling interval (CI) and the prematurity index (PI) have been shown to accurately differentiate between benign and malignant VA in people, where ventricular arrhythmias are known to be associated with an increased risk of development of signs of heart failure or sudden death. In this study, we characterized ventricular arrhythmias in dogs with symptomatic and asymptomatic DMVD. Seventy dogs with naturally-occurring DMVD and ventricular arrhythmias were retrospectively studied. A cross-sectional investigation including dogs with either symptomatic (stages C/D; n = 41) or asymptomatic (stages B1/B2; n = 29) DMVD was performed. Electrocardiographic tracings were reviewed to calculate both the CI and PI. In eight dogs these indices were compared with those obtained from both a Holter recording and a standard ECG tracing and no statistical differences were found (CI, p = 0.97; PI, p = 0.17). Even though CI and PI were determined in all animals enrolled in the study, VPC characteristics were only compared between symptomatic and asymptomatic dogs when a 24-h Holter recording was available (n = 49). The PI was different (p = 0.01) between symptomatic (0.65 ± 0.17) and asymptomatic (0.56 ± 0.18) dogs, but CI was considered similar (p = 0.91). Also, the symptomatic dogs had more polymorphic VPC (p = 0.002) and supraventricular arrhythmias (p = 0.0002) than the asymptomatic animals. Polymorphism, and repeating patterns of ventricular premature complexes, were characteristics frequently present in overtly symptomatic animals affected by mitral endocardiosis.

P wave dispersion in obese dogs with and without mitral valve disease / Dispersão da onda P em cães obesos apresentando ou não doença valvar mitral

ABSTRACT: Pwave dispersion (Pd) is an electrocardiographic index defined as the difference between the minimum and maximum Pwave duration in multiple leads. The augmentation of Pd reflects the discontinuous and inhomogeneous atrial depolarization resulting from cardiac and non-cardiac conditions. In humans, an increased Pd is associated with the development of cardiac arrhythmias, particularly atrial fibrillation. To investigate Pd in obese dogs, we enrolled 76 dogs, which were classified in four distinct categories according to body condition and the existance of valve insufficiency: obese dogs (O), dogs with both obesity and cardiac disease (O+CD), lean dogs with cardiac disease (CD) and healthy controls (H). To be included in the study, all dogs underwent an electrocardiographic and echocardiographic assessment. We reported significantly higher Pd in the animals included in categories O, O+CD and CD (18.0±7.6ms, 16.1±4.4ms, 12.1±4.3ms, respectively) as compared to the healthy subjects (7.3±2.2ms). Also, significant correlations between Pd and both the body mass index and body fat percentage were documented for the obese dogs. However, no association between Pd and LA/Ao could be identified in patients belonging to the O, O+CD and H categories. Thus, we have demonstrated that obese dogs, regardless of their valvular competency status, present high Pd values, suggesting an impaired propagation of atrial electrical impulse.

RESUMO: A dispersão da onda P (Pd) é um índice eletrocardiográfico definido como a diferença entre as durações máxima e mínima da onda P em múltiplas derivações. O aumento da Pd reflete a despolarização discontínua e não homogênea resultante de condições cardíacas e não cardíacas. Em seres humanos, uma Pdaumentada está associada com o desenvolvimento de arritmias cardíacas, particularmente fibrilação atrial. Com o intuito de investigar a Pd em cães obesos, foram selecionados 76 cães, os quais foram classificados em quatro categorias distintas, de acordo com sua condição corporal e a existência de insuficiência valvar: cães obesos (O), cães com obesidade e doença cardíaca (O+CD), cães magros com doença cardíaca (CD) e cães saudáveis usados como controle (H). Uma vez selecionados para o estudo, todos os cães foram submetidos às avaliações eletrocardiográfica e ecocardiográfica. Os resultados mostraram maior Pd nos animais pertencentes aos grupos O, O+CD e CD (18.0±7.6ms, 16,1±4,4ms, 12,1±4,3ms, respectivamente) quando comparados aos cães saudáveis (7.3±2.2ms). Além disso, foram verificadas correlações significativas entre Pde tanto o índice de massa corporal quanto o percentual de gordura corporal nos cães obesos. Entretanto, não se identificou associação entre Pd e a relação AE/Ao nos pacientes das categorias O, O+CD e H. Dessa forma, foi possível demonstrar que cães obesos, independentemente do estado de competência valvar, apresentam Pd elevada, fato que sugere comprometimento da propagação do impulso elétrico atrial.

Use of focus assessed transthoracic echocardiography (FATE) in the veterinary emergency room / Aplicabilidade da avaliação ecocardiográfica transtorácica focada (FATE) na sala de emergência veterinária

ABSTRACT: The use of bedside focus assessed transthoracic echocardiography (FATE) is widespread in human medicine, and the potential for veterinary medicine has only recently been investigated. Focused echocardiographic examination can be beneficial in critically ill patients compared to other bedside diagnostic methods, as well as facilitating rapid therapeutic approaches in the emergency room. The aim of this review is to discuss FATE and identify its main applications in veterinary medicine. In this context, FATE has proved to be benefical even when carried out by a non-cardiologist physician or veterinarian. However, a few references on this subject exist in the veterinary literature and there is still a need for standardization of this technique for use in animals.

RESUMO: A avaliação ecocardiográfica transtorácica focada (FATE) utilizada em pacientes à beira leito já é bastante difundida na medicina, e apenas, recentemente tem se discutido a respeito deste assunto na medicina veterinária. Este exame pode trazer diversos benefícios aos pacientes críticos comparado aos outros métodos diagnósticos, além de facilitar e agilizar condutas terapêuticas na sala de emergência. O objetivo desta revisão é abordar a respeito desta modalidade de exame e identificar quais são suas principais aplicabilidades na medicina veterinária. Dentro deste contexto, a FATE tem se mostrado benéfica inclusive quando realizada por médicos ou veterinários não cardiologistas. No entanto, poucas são as referêcias veteriárias a respeito deste assunto e ainda há necessidade de uma padronização desta técnica para uso em animais.

Aortic stenosis with abnormal eccentric left ventricular remodeling secondary to hypothyroidism in a Bourdeaux Mastiff / Estenose aórtica com remodelamento excêntrico anormal do ventrículo esquerdo secundário ao hipotireoidismo em um cão Dogue de Bordeaux

ABSTRACT: This paper describes a case of congenital aortic stenosis with eccentric left ventricular hypertrophy associated with hypothyroidism in a 1-year-old Bourdeaux Mastiff dog. The dog had ascites, apathy, alopecic and erythematous skin lesions in different parts of the body. A two-dimensional echocardiogram revealed aortic valve stenosis, with poststenotic dilation in the ascending aorta. The same exam showed eccentric hypertrophy and dilation of the left ventricle during systole and diastole. Aortic stenosis usually results in concentric left ventricular hypertrophy instead of eccentric hypertrophy; and therefore, this finding was very unusual. Hypothyroidism, which is uncommon in young dogs, may be incriminated as the cause of ventricular dilation, making this report even more interesting. Because hypothyroidism would only result in dilatation, the eccentric hypertrophy was attributed to pressure overload caused by aortic stenosis. Thus, cardiac alterations of this case represent a paradoxical association of both diseases.

RESUMO: Este trabalho descreve um caso de estenose aórtica congênita com hipertrofia excêntrica do ventrículo esquerdo associado ao hipotireoidismo em um cão Dogue de Bordeaux. O cão, de um ano de idade, apresentava ascite, apatia, lesões cutâneas alopécicas e eritematosas generalizadas. Na ecocardiografia bidimensional foi observada estenose da valva aórtica, com dilatação pós-estenótica em aorta ascendente. Foi detectado, no mesmo exame, hipertrofia excêntrica e dilatação do ventrículo esquerdo em sístole e diástole. Usualmente, como consequência, a estenose aórtica causa hipertrofia concêntrica do ventrículo esquerdo e não hipertrofia excêntrica, sendo este achado infrequente em tal cardiopatia. O hipotireoidismo, incomum em cães jovens, pode representar a causa da dilatação ventricular observada, o que torna mais relevante esse relato. Como no hipotireoidismo é esperado apenas dilatação, a hipertrofia excêntrica supostamente é atribuída à sobrecarga de pressão causada pela estenose aórtica. Dessa forma, as alterações cardíacas deste caso representam uma associação paradoxal das duas afecções.

MicroRNAs in veterinary cardiology / MicroRNAs em cardiologia veterinária

ABSTRACT: The use of biomarkers is an important recent development in veterinary medicine. Biomarkers allow non-invasive quantification of substances with diagnostic and prognostic potential in several diseases. The microRNAs are small, non-coding RNAs that regulate gene expression and are expressed in different forms in many diseases. Reduced or over-expression of microRNAs showed to be part of the pathogenesis of some heart diseases in humans and animals. Diagnostic and therapeutic value of measuring microRNAs in veterinary cardiology is increased because abnormal expression can be managed by the use of antagonists (in the case of overexpression) and mimicking (in the case of underexpression). Thus, this literature review aimed to compile scientific evidence of dysregulation of microRNAs expression in different cardiac diseases being one of the promises in the therapeutic field and diagnosis of veterinary cardiology. MicroRNAs not only have potential as a biomarker but may also help in elucidation of aspects of the pathogenesis of a variety of diseases.

RESUMO: Os biomarcadores vêm crescendo na medicina veterinária, pois permitem, de forma não invasiva, a quantificação de substâncias com potencial para avaliação prognóstica e diagnóstica em diversas doenças. Os microRNAs são pequenos RNAs não codificantes que regulam a expressão de genes e são expressos de diferentes formas em diversas doenças. A sua super ou subexpressão já foi evidenciada como parte da patogênese de cardiopatias em seres humanos e animais. O controle dessa anormalidade de expressão pode ser obtido pela utilização de antagonistas (em casos de superexpressão) e mimetizadores (em casos de subexpressão). Dessa forma, esta revisão de literatura tem como objetivo compilar as evidências científicas da desregulação da expressão de microRNAs nas diferentes doenças cardíacas, sendo essa uma das promessas no campo terapêutico e diagnóstico da cardiologia veterinária, permitindo não só a sua utilização como biomarcador, mas também com aspecto elucidativo da patogênese de diversas doenças.

Assessment of umbilical artery flow and fetal heart rate to predict delivery time in bitches.

The aim of this study was to quantitatively investigate the oscillation of the fetal heart rate (HR) in advance of normal delivery and whether this index could be used to indicate impending delivery. In addition, fetal HR oscillation and umbilical artery resistive index (RI) were correlated to determine if the combination of these parameters provided a more accurate prediction of the time of delivery. Sonographic evaluation was performed in 11 pregnant bitches to evaluate the fetal HR and umbilical artery RI at the following antepartum times: 120 to 96 hours, 72 to 48 hours, 24 to 12 hours, and 12 to 1 hours. Statistical analysis indicated a correlation between the oscillation of fetal HR and the umbilical artery RI. As delivery approached a considerable reduction in the umbilical artery RI was documented and greater oscillations between maximum and minimum HRs occurred. We conclude that the quantitative analysis of fetal HR oscillations may be used to predict the time of delivery in bitches. The combination of fetal HR and umbilical artery RI together may provide more accurate predictions of time of delivery.

VENTRICULAR SEPTAL DEFECT IN A CRAB-EATING FOX (CERDOCYON THOUS).

Congenital heart diseases are not commonly diagnosed in wild animals. It is not surprising that few reports exist in the literature, so that prevalence of these anomalies is unknown in wild species. We report a case of a ventricular septal defect documented in a free-ranging crab-eating fox (Cerdocyon thous). This animal presented with rapid, labored breathing, and on physical examination, pulmonary crackles and a holosystolic murmur were auscultated. The echocardiogram with Doppler showed discontinuity of the dorsal section of the ventricular septum, which allowed a turbulent systolic flow to move from the left to the right ventricle. The postmortem examination confirmed the absence of a dorsal connection between the septum and the atrioventricular junction, and pronounced left ventricular myocardial dilation was observed on histopathology. To the authors' knowledge, this is the first report of a perimembranous ventricular septal defect in a crab-eating fox.

Canine fetal echocardiography: correlations for the analysis of cardiac dimensions.

The aim of this study was to develop regression models for correlation of canine fetal heart development with body size to characterize normal development or suggest cardiac anomalies. Twenty clinically healthy pregnant bitches, either brachycephalic and non-brachycephalic, were examined ultrasonographically. Transabdominal fetal echocardiography was conducted every 4 days from the beginning of cardiac chambers differentiation until parturition. Ten cardiac parameters were measured: length, width and diameter of the heart; heart area; left and right ventricular dimensions; left and right atrial dimensions; and aortic and pulmonary artery diameter. Femoral length, biparietal diameter and abdominal cross-sectional area were also recorded. Regression equations were developed for each parameter of fetal body size, and linear and logarithmic models were compared. The model with the highest correlation coefficient was chosen to produce equations to calculate relative dimensions based on the correlations. Only the left-ventricular chamber differed between the two racial groups. Biparietal diameter was the independent parameter that produced the highest correlation coefficient for the most fetal cardiac dimensions, although good correlations were also observed using femoral length and abdominal cross-sectional area. Heart width and heart diameter were used as surrogates of cardiac development, as these measurements showed the best statistical correlation. Quantitative evaluation of fetal cardiac structures can be used to monitor normal and abnormal cardiac development.

Frequência de ovinos soropositivos para lentivírus de pequenos ruminantes no município de Colinas do Tocantins, estado do Tocantins, Brasil / Frequency of antibodies against ovine Lentivirus in sheep in Colinas do Tocantins, Tocantins state, Brazil

Maedi-Visna (MV) é uma enfermidade causada por lentivírus de pequenos ruminantes com evolução crônica e em grande parte dos casos sinais clínicos inaparentes. O diagnóstico da doença é baseado em sinais clínicos e dados epidemiológicos, sendo a imunodifusão em gel de ágar (IDGA) o método padrão para a detecção sorológica de anticorpos contra o lentivírus. Sabendo que o estado do Tocantins possui potencial para o desenvolvimento da ovinocultura e que grande parte dos produtores de Colinas do Tocantins, no referido estado, possui interesse em estabelecer criação racional, esta pesquisa teve por objetivo a realização de um estudo acerca da soroprevalência da doença. Foram coletadas 369 amostras de sangue de ovinos, independentemente de raça, sexo e idade, de diferentes propriedades rurais do município para diagnóstico de MV utilizando a técnica de IDGA. Após as análises laboratoriais, para avaliação dos resultados no tocante às categorias, foi utilizado o teste exato de Fisher e também foi calculado o odds ratio , com intervalo de confiança de 95% para verificação da idade como possível fator de risco ou de proteção. Constatou-se que 6 animais (1,62%) se apresentaram positivos no IDGA. Diante desses resultados, foi possível concluir que a frequência de ovinos soropositivos no município é baixa.(AU)

Maedi-Visna is a disease caused by a small ruminant lentivirus, with a chronic evolution and, in most cases, unapparent signs. Its diagnosis is based on clinical signs and epidemiological data, with the agar gel immunodiffusion (AGID) test being the classical method for detecting antibodies against lentiviruses. Considering that the state of Tocantins has the potential to develop sheep breeding and that the majority of producers from Colinas do Tocantins city has shown an interest in establishing a rational breeding, this study aimed to determine the prevalence of such disease in that region. A total of 369 blood samples was drawn from sheep bred in several farms of that town, regardless of breed, gender, and age. Every sample underwent an AGID to test for Maedi-Visna. After the laboratory analyses were concluded, the Fisher's exact test was used to evaluate the results against the categories. Also, the odds ratio, with 95% confidence interval, was calculated to check whether age played a role as either a risk or protective factor in these results. It was found that six animals (1.62%) were positive in AGID, therefore concluding that the frequency of seropositivity in that region is low.(AU)

Canine visceral leishmaniasis and Chagas disease among dogs in Araguaína, Tocantins.

The present study analyzed serum samples from 111 male and female dogs of various ages from the municipality of Araguaína in the State of Tocantins, Brazil. Serological diagnosis of canine visceral leishmaniasis (CVL) was initially performed at the Central Laboratory (Laboratório Central - LACEN) of Araguaína, resulting in 61 positive samples by an indirect immunofluorescence assay (IIFA) (≥1:40) and 50 non-reactive samples. The same samples were analyzed at the São Paulo Institute of Tropical Medicine (Instituto de Medicina Tropical de São Paulo - IMTSP) by an enzyme-linked-immunosorbent assay (ELISA), resulting in 57 positive samples (51.35%) and 54 negative samples (48.64%). The Kappa coefficient of agreement between the tests was 0.74. The serum samples were also subjected to a diagnostic assay for Trypanosoma cruzi (Trypomastigote Excreted/Secreted Antigens -TESA-blot) that detected five suspect animals; three of those animals were positive for leishmaniasis by ELISA but negative by IIFA. These findings suggest that the canine population of Araguaína may be simultaneously infected with Leishmania chagasi and T. cruzi. The results obtained demonstrate the difficulty of using serology to detect CVL, thus emphasizing the necessity for a reference test to diagnose CVL, particularly in regions where the infection is endemic.

Prevalência de anticorpos anti-Brucella ovis e anti-Brucella abortus em ovinos do município de Colinas, Tocantins, Brasil / Prevalence of anti-Brucella ovis and anti-Brucella abortus in sheep in the city of Colinas, Tocantins, Brazil

A brucelose é uma enfermidade infecciosa, causada por bactérias do gênero Brucella spp. responsáveis por desordens reprodutivas nos animais, especialmente nos ruminantes. Este trabalho objetivou determinar a presença de anticorpos anti-Brucella ovis e anti-Brucella abortus em ovinosde 14 propriedades cadastradas na Associação de Ovinocultores do município de Colinas, Tocantins,Brasil. Para isso, amostras de soro de 450 ovinos foram analisadas por meio da aglutinação rápida em placa com Antígeno Acidificado e Tamponado (AAT) e, quando reagentes, foram realizados os testes de Aglutinação Lenta em Tubos (SAT) e 2-Mercaptoetanol (2-ME) para pesquisar cepas lisas (B. abortus). Para a pesquisa de cepas rugosas (B. ovis), foi realizada a Imunodifusão em Gel de Ágar (IDGA) e, quando reagente, foi realizada a Fixação de Complemento (FC). Das amostras analisadas,142 (31,6por cento) reagiram ao teste de IDGA, dentre estas, apenas 4 (2,8por cento) foram confirmadas na FC.Ante o AAT, apenas 20 (4,4por cento) se mostraram positivas, das quais 14 (70por cento) foram confirmadas noSAT/2-ME. Os resultados obtidos nos testes de FC e SAT/2-ME e analisados pelo Teste de Fisher e OR demonstraram significância estatística entre a positividade e a faixa etária, sendo maior a chance de um animal em reprodução ser positivo para brucelose.