Risk factors associated with mammary tumors in female dogs / Fatores de risco para tumores mamários em cadelas de Uberlândia e Patos de Minas, Minas Gerais

Mammary tumors in female dogs are the most frequent and corresponds to half of the canine tumors. The objectives of this study were to determine the risk factors associated with the occurrence of mammary tumors in female dogs and to evaluate the macroscopic characteristics of these neoformations, using 386 dogs from the "Outubro Rosa Pets" events done within the cities of Uberlândia and Patos de Minas, Minas Gerais State, Brazil, in 2015 (n=194), 2016 (n=105) and 2017 (n=87). For the determination of risk factors, the binary logistic regression test (P<0.05) was performed. The occurrence of mammary tumors was 23.6% (91/386). The significant risk factors identified were increased age (P<0.001), overweight (P=0.048) and non-castration (P<0.001) with a chance of, respectively, 1.6, 2.3 and 9.3 times for the development of mammary tumors. In dogs with mammary tumors (n=91), 153 lesions were present, of which 39 female dogs had two or more lesions (42.8%). Most of the lesions were at the caudal abdominal (M4) and inguinal (M5) mammary glands (60.13%, 92/153). Relative to the size of the lesions, it was observed that in 78% of the female dogs the lesions were determined asT1 (<3cm), 16.5% were T2 (3-5cm) and 5.5% T3 (>5cm). At least 15.4% (14/91) of the dogs had one of the regional lymph nodes increased. In conclusion, the occurrence of mammary tumors in the evaluated population was 23.6% and that age, overweight and non-realization of ovariohysterectomy are risk factors associated with the development of mammary tumors.(AU)

Em cadelas os tumores mamários são os mais frequentes e correspondem a aproximadamente metade dos tumores em cães. Este estudo teve os objetivos de determinar os fatores de risco envolvidos na ocorrência de tumores mamários em cadelas e avaliar as características macroscópicas destas neoformações, utilizando 386 cadelas do evento "Outubro Rosa Pets" nos municípios de Uberlândia e Patos de Minas, Minas Gerais, Brasil, em 2015 (n=194), 2016 (n=105) e 2017 (n=87). Para a determinação dos fatores de risco utilizou-se o teste de Regressão logística binária (P<0,05). A ocorrência de tumores mamários foi de 23,6% (91/386). Os fatores de risco significativos identificados foram aumento da idade (P<0,001), sobrepeso (P=0,048) e não-castração (P<0,001) com a chance de, respectivamente, 1,6, 2,3 e 9,3 vezes de desenvolvimento de tumores mamários. Nas cadelas com tumores mamários (n=91), constatou-se a presença de 153 lesões, sendo que 39 cadelas apresentaram duas ou mais lesões (42,8%). A maioria das lesões localizaram-se nas mamas abdominais caudais (M4) e inguinais (M5) (60,13%; 92/153). Em relação ao tamanho das lesões, observou-se que 78% das cadelas eram T1 (<3cm), 16,5% T2 (3-5cm) e 5,5% T3 (>5cm). Pelo menos 15,4% (14/91) das cadelas apresentaram um dos linfonodos regionais aumentados. Conclui-se que a ocorrência dos tumores mamários na população avaliada foi de 23,6% e que a idade, sobrepeso e não ovariohisterectomia são fatores de risco para o desenvolvimento de tumores mamários.(AU)

Left atrial size and contractile function in healthy dogs and dogs with chronic mitral valve disease / Tamanho e função sistólica atrial esquerda em cães sadios e com doença valvar crônica de mitral

In humans, left atrial enlargement and reduced contractile functions are associated with adverse cardiovascular events and a poor prognosis in many dilatation of the left atrium occurs with the gradual evolution of chronic mitral valve disease and is well diseases. The left atrium is the most compromised cardiac chamber in dogs with chronic mitral valve disease (CMVD). Therefore, this study aimed to compare the main parameters of left atrial enlargement (left atrium/aorta ratio, left atrial diameter and volume indices) and contractile function (transmitral flow peak velocity A wave and time velocity integral, atrial fraction, and atrial ejection force) at different stages of valve disease, and correlate the left atrial diameter, volume, and contractile function indices with echocardiographic variables predictive of heart failure in dogs (transmitral flow peak velocity E wave, E wave/IVRT ratio, E wave/E´wave ratio, and E wave/A wave ratio). The results showed that progressive characterized by the left atrium/aorta ratio and left atrium volume index. The left atrial diameter and volume indices and left atrium/aorta ratio correlated positively with the transmitral flow peak velocity E wave and E wave/IVRT ratio, which are important indices of diastolic function. The left atrial contractile function indices increased as CMVD evolved. Except for the atrial fraction, the left atrial contractile function indices correlated with the left ventricular filling pressure indices.(AU)

O tamanho e a função atrial esquerda estão relacionados em humanos com eventos cardiovasculares adversos e prognóstico nas principais cardiopatias. Na doença valvar crônica de mitral (DVCM) em cães, o átrio esquerdo é a câmara cardíaca mais comprometida. Portanto, os objetivos deste estudo foram comparar os principais parâmetros de aumento atrial esquerdo (relação átrio esquerdo/aorta, índice do diâmetro atrial esquerdo e índice do volume atrial esquerdo) e função contrátil de átrio esquerdo (velocidade máxima e integral de velocidade da onda A do fluxo transvalvar mitral, fração atrial e força de ejeção atrial) nos diferentes estágios da doença valvar; correlacionar diâmetro e volume atrial esquerdo e os índices de função contrátil atrial esquerda com as variáveis ecocardiográficas preditivas de insuficiência cardíaca em cães (velocidade máxima da onda E do fluxo transvalvar mitral, relação E/TRIV, relação E/E'par e relação E/A). Os resultados mostraram que com a evolução progressiva da doença valvar crônica de mitral, ocorre dilatação progressiva do átrio esquerdo, bem caracterizada pela relação átrio esquerdo/aorta e pelo índice de volume atrial esquerdo. O índice do diâmetro atrial esquerdo, o índice de volume atrial esquerdo e a relação átrio esquerdo/aorta correlacionam-se, positivamente, com a velocidade da onda E e com a relação E/TRIV, que são importantes índices de função diastólica. Os índices de função contrátil do átrio esquerdo aumentam à medida que a DVCM evolui. Os índices de função contrátil do átrio esquerdo apresentam correlação positiva com os índices de pressão de enchimento ventricular esquerdo, exceção feita à fração atrial.(AU)

Clinical monitoring of cardiac output assessed by transoesophageal echocardiography in anaesthetised dogs: a comparison with the thermodilution technique.

BACKGROUND: Cardiac output (CO) is an important haemodynamic parameter to monitor in patients during surgery. However, the majority of the techniques for measuring CO have a limited application in veterinary practice due to their invasive approach and associated complexity and risks. Transoesophageal echocardiography (TEE) is a technique used to monitor cardiac function in human patients during surgical procedures and allows CO to be measured non-invasively. This prospective clinical study aimed to compare the transoesophageal echocardiography using a transgastric view of the left ventricular outflow tract (LVOT) and the thermodilution (TD) technique for the assessment of CO during mean arterial pressure of 65-80 mmHg (normotension) and <65 mmHg (hypotension) in dogs undergoing elective surgery. Eight dogs were pre-medicated with acepromazine (0.05 mg/kg, IM), tramadol (4 mg/kg, IM) and atropine (0.03 mg/kg, IM), followed by anaesthetic induction with propofol (3-5 mg/kg IV) and maintenance with isoflurane associated with a continuous infusion rate of fentanyl (bolus of 3 µg/kg followed by 0.3 µg/kg/min). The CO was measured by TEE (COTEE) and TD (COTD) at the end of expiration during normotension and hypotension (induced by isoflurane). RESULTS: There was a strong positive correlation between COTEE and COTD ​​(r = 0.925; P < 0.0001). The bias between COTD and COTEE was 0.14 ± 0.29 L/min (limits of agreement, -0.44 to 0.72 L/min). The percentage error of CO measured by the two methods was 12.32%. In addition, a strong positive correlation was found between COTEE and COTD during normotension (r = 0.995; P < 0.0001) and hypotension (r = 0.78; P = 0.0223). CONCLUSIONS: The results of this study indicated that the transgastric view of the LVOT by TEE was a minimally invasive alternative to clinically monitoring CO in dogs during anaesthesia. However, during hypotension, the CO obtained by TEE was less reliable, although still acceptable.

Blood lactate concentration in diabetic dogs.

Human diabetic patients may have increased lactate levels compared to non-diabetics. Despite the use of lactate levels in critical care assessment, information is lacking for diabetic dogs. Therefore, this prospective cross-sectional clinical study aimed to determine lactate concentrations in 75 diabetic dogs [25 newly diagnosed non-ketotic diabetics, 25 under insulin treatment, and 25 in diabetic ketoacidosis (DKA)], compared to 25 non-diabetic dogs. Lactate levels (mmol/L) were not different among groups (P = 0.20); median and 25th to 75th percentile were 2.23 and P25-75 = 1.46 to 2.83 for controls, 1.69 and P25-75 = 1.09 to 2.40 for newly diagnosed non-ketotic diabetics, 2.27 and P25-75 = 1.44 to 2.90 for dogs under insulin treatment for at least 30 days, and 2.40 and P25-75 = 1.58 to 3.01 for dogs in DKA. Longitudinal studies assessing both isomers (L- and D-lactate) are needed to better elucidate the role of lactate in the pathophysiology of diabetes acid-base status in dogs.

La concentration de lactate de sang chez les chiens diabétiques. Des patients humains avec diabète peuvent présenter augmentation des niveaux de lactate, quand comparés aux non diabetiques. Bien que est utilisé d'évaluer les patients dans un état critique, cette information manque pour les chiens diabétiques. Par conséquent, cette étude clinique s'agit d'une prospective transversale en vue de detérminer les concentrations du lactate en 75 chiens diabétiques [25 au moment du diagnostic, 25 sous traitement à l'insuline et 25 dans l'acido-cétose diabétique (ACD)], par rapport aux 25 chiens non diabétiques. Les niveaux de L-lactate ne différaient pas entre les groupes (P = 0,20). Les valeurs médianes et les centiles 25 % et 75 % étaient de 2,23 mmol/L (P25­75 = 1,46 à 2,83) pour les contrôles, 1,69 mmol/L (P25­75 = 1,09 à 2,40) au diagnostic, 2,27 mmol/L (P25­75 = 1,44 à 2,90) sous traitement à l'insuline pendant au moins 30 jours, et 2,40 mmol/L (P25­75 = 1,58 à 3,01) dans ACD. Des études longitudinales évaluant les deux isomères (L et D-lactate) sont nécessaires pour élucider son rôle dans la physiopathologie et le déséquilibre acide-base chez les chiens diabétiques.(Traduit par Ana Carolina Possas Viana).

Pulse pressure variation as a guide for volume expansion in dogs undergoing orthopedic surgery.

OBJECTIVE: To investigate whether pulse pressure variation (PPV) can predict fluid responsiveness in healthy dogs during clinical surgery. STUDY DESIGN: Prospective clinical study. ANIMALS: Thirty-three isoflurane-anesthetized dogs with arterial hypotension during orthopedic surgery. METHODS: Fluid challenge with lactated Ringer's solution (15 mL kg-1 in 15 minutes) was administered in mechanically ventilated dogs (tidal volume 10 mL kg-1) with hypotension [mean arterial pressure (MAP) < 65 mmHg]. The volume expansion was considered effective if cardiac output (CO; transesophageal Doppler) increased by ≥ 15%. Cardiopulmonary data were analyzed using two-way ANOVA, receiver operating characteristics (ROC) curves and Spearman coefficient; p < 0.05 was considered significant. RESULTS: Effective volume expansion, mean ± standard deviation 42 ± 4% increase in CO (p < 0.0001) was observed in 76% of the dogs, resulting in a decrease in PPV (p < 0.0001) and increase in MAP (p < 0.0001), central venous pressure (CVP; p = 0.02) and ejection fraction (p < 0.0001) compared with before the fluid challenge. None of these changes occurred when volume expansion resulted in a nonsignificant CO increase of 4 ± 5%. No significant differences were observed in blood gas analysis between responsive and nonresponsive dogs. The increase in CO was correlated with the decrease in PPV (r = -0.65; p < 0.0001) but absolute values of CO and PPV were not correlated. The PPV performance (ROC curve area: 0.89 ± 0.06, p = 0.0011) was better than that of CVP (ROC curve area: 0.54 ± 0.12) and MAP (ROC curve area: 0.59 ± 0.13) to predict fluid responsiveness. The best cut-off for PPV to distinguish responders and nonresponders was 15% (50% sensitivity and 96% specificity). CONCLUSIONS AND CLINICAL RELEVANCE: In mechanically ventilated, healthy, isoflurane-anesthetized dogs, PPV predicted fluid responsiveness to volume expansion, and MAP and CVP did not show such applicability.

Seroprevalence and risk factors of antibodies against Leptospira spp. in ovines from Uberlândia municipality, Minas Gerais state, Brazil

The objectives of the present study were to verify the seroprevalence of anti-Leptospira spp. antibodies, identify the most frequent serovars and the risk factors associated with the infection in Uberlândia, Minas Gerais, Brazil . A total of 334 ovines blood samples were collected in 12 farms from Uberlândia municipality to be evaluated by means the Microscopic Agglutination Test (MAT) against 22 serovars of Leptospira spp. and an epidemiologic questionnaire was applied for each farm in order to correlate with risk factors of leptospirosis: sex, age and breed as well as contact with cattle, contact with dogs and presence of rodents. The prevalence of seropositive to MAT was found in seventy four ovines (22.2 percent; CI 95 percent 17.6-26.4 percent), with titers ranging from 100 to 3200. The most frequent serovars identified were: Hardjo, Autumnalis, Hardjo and Wolffi association and Grippotyphosa. Statistically significant differences were found in males, pure breeds and presence of rodents (p<0.05). The prevalence of anti-Leptospira spp. antibodies found in the present study demonstrated that this bacterium occurs in ovines of Uberlândia municipality, MG, Brazil . The need for the adoption of efficient management for the control of rodents and infection in ovines in order to avoid leptospirosis in the local flocks and future transmission to humans.

Cinética da resposta imune humoral de cães jovens imunizados contra Leptospira interrogans / Kinetics of the humoral immune response of dogs young immunized with Leptospira interrogans

Objetivou-se analisar a resposta imune humoral contra Leptospira interrogans mediante a utilização da prova de soroaglutinação microscópica (SAM) em 26 cães jovens, sendo 17 de raça definida (Grupo A) e nove sem raça (Grupo B), de ambos os sexos, pertencentes a canis e ambientes domiciliares em Uberlândia, Minas Gerais. Os cães foram vacinados com bacterina inativada comercial polivalente com os sorovares Canicola, Grippotyphosa, Icterohaemorrhagiae e Pomona. O esquema vacinal baseou-se em três imunizações. A primovacinação foi realizada aos quarenta e cinco dias de idade, considerado dia zero, e após dois reforços com intervalos de trinta dias cada. Sete colheitas sanguíneas de cada cão foram efetuadas do dia zero até aos 180 dias pós-vacinais, com intervalos de trinta dias cada. Não foram detectados títulos pré-vacinais para os sorovares Canicola, Icterohaemorrhagiae e Grippotyphosa no dia zero. Apenas um cão do grupo A foi reagente com título 1:100 contra o sorovar Pomona na primeira colheita. Não houve diferença estatística entre os títulos de anticorpos aglutinantes entre os Grupos A e B (p>0,05), induzidos pela bacterina comercial utilizada, exceto na colheita II (p<0,05), na qual o grupo B apresentou títulos para o sorovar Autumnalis em todos os cães avaliados, enquanto que, no grupo A, 64,7 por cento dos cães não foram reagentes a nenhum sorovar testado. No dia 30, títulos para o sorovar Autumnalis que persistiram até os 180 dias pós-vacinais, em ambos os grupos, variando apenas a intensidade da resposta imunológica sem diferença estatística significativa. Para avaliação da eficiência vacinal da bacterina anti-Leptospira, a presente pesquisa alerta para os ricos à infecção que os cães vacinados anualmente estão submetidos.

The objective was to analyze the humoral immune response against Leptospira interrogans using the microscopic agglutination test (MAT) in 26 young dogs, and 17 mixed breed (Group A) and nine mixed breed (Group B) of both sexes, pertaining to kennels and home environments in Uberlandia, Minas Gerais. Dogs were vaccinated with commercial inactivated polyvalent bacterin with Canicola, Grippotyphosa, Icterohaemorrhagiae and Pomona serovars. The immunization schedule was based on three immunizations. The first vaccination was performed at forty-five days of age, considered day zero, and after two boosters at intervals of thirty days each. Seven blood samples from each dog were made from time zero up to 180 days post-vaccination, at intervals of thirty days each. Titles have not been detected pre-vaccination against serovars Canicola, and Icterohaemorrhagiae Grippotyphosa on day zero. Only one dog in group A was reactive with a titer of 1:100 against Pomona in the first harvest. There was no statistical difference between the agglutinating titers between Groups A and B (p>0.05) induced by commercial vaccine used, except at harvest II (p<0.05), in which the group B presented evidence to serovar Autumnalis in all dogs evaluated, whereas in group A, 64.7 percent of dogs were not reactive to any serovar tested. There were on the 30th title to serovar Autumnalis that persisted until 180 days post-vaccination in both groups, varying only the intensity of immune response without significant statistical difference. To assess the efficiency of vaccine culture anti-Leptospira this research to warn the risks infection that dogs are vaccinated annually submitted.

Seroprevalence and risk factors of antibodies against Leptospira spp. in ovines from Uberlândia municipality, Minas Gerais state, Brazil.

The objectives of the present study were to verify the seroprevalence of anti-Leptospira spp. antibodies, identify the most frequent serovars and the risk factors associated with the infection in Uberlândia, Minas Gerais, Brazil. A total of 334 ovines blood samples were collected in 12 farms from Uberlândia municipality to be evaluated by means the Microscopic Agglutination Test (MAT) against 22 serovars of Leptospira spp. and an epidemiologic questionnaire was applied for each farm in order to correlate with risk factors of leptospirosis: sex, age and breed as well as contact with cattle, contact with dogs and presence of rodents. The prevalence of seropositive to MAT was found in seventy four ovines (22.2%; CI 95% 17.6-26.4%), with titers ranging from 100 to 3200. The most frequent serovars identified were: Hardjo, Autumnalis, Hardjo and Wolffi association and Grippotyphosa. Statistically significant differences were found in males, pure breeds and presence of rodents (p<0.05). The prevalence of anti-Leptospira spp. antibodies found in the present study demonstrated that this bacterium occurs in ovines of Uberlândia municipality, MG, Brazil. The need for the adoption of efficient management for the control of rodents and infection in ovines in order to avoid leptospirosis in the local flocks and future transmission to humans.