Determination of echocardiographic parameters in spider monkey (Ateles spp.) collectives in captivity sedated with ketamine and midazolam

Nonhuman primates have long been studied and managed in research centers, zoos, and farms, but there is still a lack of information regarding their illnesses. The present study aimed to establish the echocardiographic parameters of normality among primates of the genus Ateles (spider monkey) that are housed at the Zoo of the City of Rio de Janeiro – RIOZOO Foundation. Nine specimens of the same species were used, 5 females and 4 males, that were clinically healthy, young adults, with an approximate captive age of 2 to 3 years, and an average weight of 8.5 kg. The animals were physically restrained with a net and soon after, chemical containment was carried out by means of an association of ketamine hydrochloride at a dose of 8 mg per kg and midazolam at 0.5 mg per kg, intramuscularly. The animals were submitted to chemical restraint to establish the clinical evaluation, blood collection for complete blood count and biochemical measurements, urine collection for urinalysis, chest X-ray in the ventro-dorsal and latero-lateral positions, and electrocardiographic exams, with all the parameters within the normal range, in addition to echocardiographic examination, which became the means by which the study parameters were acquired. During this examination, the following values were evaluated: cardiac output, ejection fraction, final cardiac volume, heart rate, left atrial diameter, aorta diameter, ratio between the diameters of the left atrium and aorta artery, thickness of the interventricular septum in diastole, diameter of the left ventricle in diastole, thickness of the free wall of the left ventricle in diastole, thickness of the interventricular septum in systole, diameter of the left ventricle in systole, thickness of the free wall of the left ventricle in the systole, left ventricular end systolic volume, left ventricular end diastolic volume, septum bending fraction, fraction of curving of the posterior wall, septal separation, and shortening fraction. With the data obtained, tables were drawn with the echocardiographic values of the species studied under sedation.