Marlos Gonçalves Sousa

Agreement between auricular and rectal measurements of body temperature in healthy cats.

Measurement of body temperature is a routine part of the clinical assessment of a patient. However, this procedure may be time-consuming and stressful to most animals because the standard site of temperature acquisition remains the rectal mucosa. Although an increasing number of clinicians have been using auricular temperature to estimate core body temperature, evidence is still lacking regarding agreement between these two methods in cats. In this investigation, we evaluated the agreement between temperatures measured in the rectum and ear in 29 healthy cats over a 2-week period. Temperatures were measured in the rectum (using digital and mercury-in-glass thermometers) and ear once a day for 14 consecutive days, producing 406 temperature readings for each thermometer. Mean temperature and confidence intervals were similar between methods, and Bland–Altman plots showed small biases and narrow limits of agreement acceptable for clinical purposes. The interobserver variability was also checked, which indicated a strong correlation between two near-simultaneous temperature readings. Results are consistent with auricular thermometry being a reliable alternative to rectal thermometry for assessing core body temperature in healthy cats.

Comparison between two methods for cardiac output measurement in propofol‐anesthetized dogs: thermodilution and Doppler

OBJECTIVE To compare cardiac output (CO) measured by Doppler echocardiography and thermodilution techniques in spontaneously breathing dogs during continuous infusion of propofol. To do so, CO was obtained using the thermodilution method (CO(TD)) and Doppler evaluation of pulmonary flow (CO(DP)) and aortic flow (CO(DA)). STUDY DESIGN Prospective cohort study. ANIMALS Eight adult dogs weighing 8.3 +/- 2.0 kg. METHODS Propofol was used for induction (7.5 +/- 1.9 mg kg(-1) IV) followed by a continuous rate infusion at 0.7 mg kg(-1) minute(-1). The animals were positioned in left lateral recumbency on an echocardiography table that allowed for positioning of the transducer at the 3rd and 5th intercostal spaces of the left hemithorax for Doppler evaluation of pulmonary and aortic valves, respectively. CO(DP) and CO(DA) were calculated from pulmonary and aortic velocity spectra, respectively. A pulmonary artery catheter was inserted via the jugular vein and positioned inside the lumen of the pulmonary artery in order to evaluate CO(TD). The first measurement of CO(TD), CO(DP) and CO(DA) was performed 30 minutes after beginning continuous infusion (T0) and then at 15-minute intervals (T15, T30, T45 and T60). Numeric data were submitted to two-way anova for repeated measurements, Pearsons correlation coefficient and Bland & Altman analysis. Data are presented as mean +/- SD. RESULTS At T0, CO(TD) was lower than CO(DA). CO(DA) was higher than CO(TD) and CO(DP) at T30, T45 and T60. The difference between the CO(TD) and CO(DP), when all data were included, was -0.04 +/- 0.22 L minute(-1) and Pearsons correlation coefficient (r) was 0.86. The difference between the CO(TD) and CO(DA) was -0.87 +/- 0.54 L minute(-1) and r = 0.69. For CO(TD) and CO(DP), the difference was -0.82 +/- 0.59 L minute(-1) and r = 0.61. CONCLUSION Doppler evaluation of pulmonary flow was a clinically acceptable method for assessing the CO in propofol-anesthetized dogs.

Variabilidade da freqüência cardíaca em cães anestesiados com infusão contínua de propofol e sufentanil

The effects of propofol and sufentanil on cardiac sympathetic and parasympathetic balance were studied, in order to evaluate if sufentanil plays a role in this balance. The heart rate variability of 12 adult dogs was assessed, after premedication with acepromazine and anesthetized with propofol and three different doses of sufentanil, ranging from 0.025 to 0.1µg/kg/min. Electrocardiograms were recorded 15 minutes after premedication and 15, 30, 60, 90, and 120 minutes after anesthetic induction. Heart rate variability was calculated in frequency domain through the analysis of 10 consecutive RR intervals. Results showed an absence of important changes in heart rate variability, although a significant decrease in heart rate was observed.

Detection of antibodies against Babesia bovis and Babesia bigemina in calves from the region of Araguaína, State of Tocantins, Brazil.

The aim of this study was to determine the seroprevalence of antibodies against B. bovis and B. bigemina in calves from the region of Araguaína, State of Tocantins, Brazil. In this research we used sera obtained from 506 calves, from both genders and of 8 to 24 months old, to detect antibodies by indirect Enzyme-Linked Immunosorbent Assay (ELISA-test). Statistical analysis of the data was performed using the Chi-square (χ²) test with Yates correction. The seroprevalence obtained was 90.5 and 91.7% for B. bigemina and B. bovis, respectively, characterizing the region as an area of enzootic stability for the species analyzed. The seroprevalence to B. bovis showed higher positivity among calves 19-24 months old.

Effects of weight loss on the cardiac parameters of obese dogs

Obesity is one of the most frequent nutritional problems in companion animals and can lead to severe health problems in dogs and cats, such as cardiovascular diseases. This research aimed to evaluate the structural and functional cardiac changes after weight loss in obese dogs. Eighteen obese healthy dogs were assigned into three different groups, according with their initial body weight: Group I (dogs up to 15 kg), Group II (dogs weighing between 15.1 and 30 kg), and Group III (dogs weighing over 30 kg). The animals were submitted to a caloric restriction weight-loss program until they lose 15% of the body weight. The M-mode echocardiogram, electrocardiogram, and blood pressure evaluations were performed before the diet has started and after the dogs have reached the target weight. Data showed a decrease in left ventricular free wall thickness during diastole and systole in Group III, decrease in the systolic blood pressure in Group III, and also in the mean blood pressure in Group II. It was possible to conclude that the weight loss program can reverse structural cardiac changes such as left ventricle eccentric hypertrophy in dogs weighing more than 30 kg, and decrease the arterial blood pressure in obese dogs.

Efeitos de diferentes frações inspiradas de oxigênio no índice biespectral em cães submetidos à infusão contínua de propofol

The effects of several inspired oxygen fractions (FiO2) on the bispectral index in spontaneously breathing dogs submitted to continuous infusion of propofol were evaluated. Eight adult mongrel dogs were used. Each animal was submitted to five anesthesias. In each procedure, the patient was allowed to breathe a different FiO2, thereby resulting in five groups, namely: G100 (FiO2 = 1), G80 (FiO2 = 0.8), G60 (FiO2 =0.6), G40 (FiO2 = 0.4), and G20 (FiO2 = 0.21). To induce anesthesia, propofol was given until the animals allowed orotracheal intubation, followed by immediate continuous infusion of drug. The initial measurement (M0) was recorded 30 minutes after the infusion of propofol onset. Additional recordings were performed at 15-minute intervals during 60 minutes (M15, M30, M45, and M60). No significant differences on BIS parameters were recorded. Regarding arterial partial pressure of carbon dioxide (PaCO2), the mean of G100 was greater than G20 at M30, whereas arterial partial pressure of oxygen (PaO2) varied according to the changes in oxygen. The mean intervals of BIS were: for G100, from 68 to 62; for G80, from 71 to 58; for G60, from 72 to 62; for G40 from 76 to 68; and for G20, from 77 to 68. In conclusion, different FiO2 does not impair BIS parameters. However, it is suggested that BIS was able to detect changes in the balance of cerebral blood flow, which was a result of changes in respiratory dynamic by the use of several inspired fractions.

Aspectos clínico-laboratoriais da infecção natural por Trypanosoma cruzi em cães de Mato Grosso do Sul

Chagas disease is caused by T. cruzi, which is transmitted essentially by vector insects, and is distributed in Argentina, Chile, Venezuela, and Brazil. Besides being an important reservoir of the disease, dogs represent the only species to develop clinical signs similar to those presented by human beings. This study was aimed at describing the clinical features of four dogs naturally infected with T. cruzi, as well as to warn that some cases might be underestimated. The animals were selected based on the serologic exams indirect fluorescent antibody test (IFAT), enzyme-linked immunosorbent assay (ELISA), immunoblotting test with T. cruzi excreted-secreted antigens (TESA-blot), and xenodiagnosis. Physical examination, chest radiographs, electrocardiogram, echocardiogram, and serum biochemistry was accomplished in every dog. The most important alterations were the enlargement of the right ventricle, the atrioventricular blocks, sinus arrest, and right bundle branch blocks, besides both systolic and diastolic dysfunction. Three animals presented hyperproteinemia, as well as CK and CK-MB profiles compatible with an active myocarditis. These are the first reported cases of dogs with solid evidences of naturally occurring T. cruzi infection in Mato Grosso do Sul State, therefore reinforcing the clinical importance and the role of these species as reservoir of the disease.

Hemodinâmica de diferentes frações inspiradas de oxigênio em cães submetidos à infusão contínua de propofol sob ventilação espontânea

Avaliaram-se os efeitos do fornecimento de diferentes fracoes inspiradas de oxigenio (FiO2) sobre os parâmetros hemodinâmicos em caes submetidos a infusao continua de propofol e mantidos em ventilacao espontânea. Foram utilizados oito caes, os quais foram empregados em cinco grupos com diferentes FiO2, G100 (FiO2 = 1), G80 (FiO2 = 0,8), G60 (FiO2 = 0,6), G40 (FiO2 = 0,4) e G20 (FiO2 = 0,21), respeitando-se um intervalo de dez dias entre cada procedimento anestesico. Os animais foram induzidos e mantidos sob anestesia com propofol na dose de 0,7mg kg-1 min-1 e, apos a intubacao orotraqueal, iniciou-se o fornecimento de oxigenio conforme a FiO2 determinada para cada grupo. As primeiras mensuracoes, da frequencia cardiaca (FC), das pressoes arteriais sistolica, diastolica e media (PAS, PAD e PAM), da resistencia vascular periferica e pulmonar (RPT e RPV), do debito cardiaco (DC); da pressao venosa central (PVC), da pressao media da arteria pulmonar (PMAP), da pressao media capilar pulmonar (PMCP), da pressao parcial de oxigenio (PaO2) e do dioxido de carbono (PaCO2) no sangue arterial, foram efetuadas 30 minutos apos o inicio da infusao do anestesico (M0), seguidas de intervalos de 15 minutos (M15, M30, M45 e M60). Os dados numericos obtidos foram submetidos a Analise de Variância, seguida pelo teste Tukey (P<0,05). Os parâmetros hemodinâmicos nao apresentaram diferencas significativas ao longo do tempo e entre os grupos. Os resultados obtidos permitiram concluir que as variaveis hemodinâmicas nao sao afetadas pelo emprego de diferentes FiO2.

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.

Eletrocardiografia computadorizada em cães da raça Beagle

Electrocardiographic parameters were studied in thirty healthy adult Beagles, using conventional and computerized methods and reading the computerized registration printed on paper. The electrocardiographic measurements of the three different tracings were analyzed in lead II. The results obtained showed that there are differences among the three methods for P wave, R wave, QRS complex, QT interval, PR interval and polarity of the T wave. Special attention should be given to these differences, depending on the chosen method.