Abstract There is a growing concern about the participation of wild hosts and reservoirs in the epidemiology of several pathogens, particularly within the context of environmental changes and the expansion of the One Health concept. The aim of this study was to investigate the presence of hemoplasmas in opossums rescued from the metropolitan region of Rio de Janeiro state, Brazil. Blood samples were collected from 15 Didelphis aurita and subjected to DNA extraction and PCR using primers for the 16S rRNA and 23S rRNA genes. Physical examination and hematological analysis were also performed. Three out of 15 opossums tested positive for hemotropic Mycoplasma spp. by PCR and showed hematological alterations such as anemia and leukocytosis. Clinical signs were non-specific and associated to traumatic lesions. The phylogenetic analysis indicated that the hemoplasma detected was positioned between 'Ca. Mycoplasma haemodidelphis' detected in D. virginiana from North American and hemoplasmas recently detected in D. aurita from the state of Minas Gerais, Brazil. This study indicates the existence of hemoplasma infections in D. aurita from the metropolitan region of Rio de Janeiro, and reinforce the need for new epidemiological inquiries to clarify the participation of these in the dynamics of circulation of tick-borne pathogens.

Resumo Há uma crescente preocupação com a participação de hospedeiros e reservatórios silvestres na epidemiologia de diversos patógenos, principalmente no contexto das mudanças ambientais e da expansão do conceito "One Health". O objetivo deste estudo foi investigar a presença de hemoplasmas em gambás resgatados da região metropolitana do estado do Rio de Janeiro, Brasil. Amostras de sangue foram coletadas de 15 Didelphis aurita e submetidas à extração de DNA e PCR utilizando-se "primers" para os genes 16S rRNA e 23S rRNA. O exame físico e a análise hematológica também foram realizados. Três dos 15 gambás testaram positivo para Mycoplasma spp. hemotrópico por PCR. Os sinais clínicos eram inespecíficos e associados a lesões traumáticas. Anemia e leucocitose foram detectadas em animais positivos. A análise filogenética indicou que o hemoplasma detectado estava posicionado entre 'Ca. Mycoplasma haemodidelphis' detectado em D. virginiana da América do Norte e hemoplasmas recentemente detectados em D. aurita do estado de Minas Gerais, Brasil. Este estudo indica a existência de infecções por hemoplasmas em D. aurita, da região metropolitana do Rio de Janeiro, e reforça a necessidade de novos inquéritos epidemiológicos, para esclarecer a participação destes na dinâmica de circulação de patógenos transmitidos por carrapatos.

SUMMARY: The thyroid glands consist of two parts called lobes located on both sides of the larynx. The aim of this study was to characterize the measures, topography and arterial irrigation of New Zealand´s rabbits thyroid glands. The anatomical dissections were performed in 36 adult cadavers, 17 males and 19 females, with a mean body mass of 2.5 kg and a mean cranium-sacral length of 40 cm. The specimens were obtained from the necropsy unit of the University. The cadavers had the thoracic aorta artery cannulated, through which 10 % formaldehyde solution was injected, followed by injection colored latex. In males, the left lobe of the thyroid gland measured 1.40x0.40x0.01cm and the right 1.36x0.56x0.01cm; in females, the left lobe measured 1.50x0.49x0.01cm and the right one was 1.37x0.48x0.01cm. There was no significant difference (p> 0.05) between the means of the measurements between males and females, but the left lobe length of the females and the right lobe width of the males were significantly higher (p <0.05). The cranial extremity of the thyroid lobes was at the level of the cricoid cartilage in almost all specimens. The caudal end showed more variable topography, from the third to the tenth tracheal ring in few specimens, but predominated at the level of the fifth ring. Invariably, arterial irrigation was determined by the left and right thyroid arteries, originating from the common carotid artery. Anastomoses between the thyroid arteries were common. The constancy in dimensions and irrigation of the thyroid gland may be advantageous in choosing the rabbit as an experimental model for the study of this gland.

RESUMEN: Las glándulas tiroides consisten en dos partes denominadas lobos que se encuentran en ambos lados de la laringe. El objetivo de este estudio fue caracterizar las medidas, topografía y vascularización de la glándula tiroides de conejos Nueva Zelanda. Las disecciones anatómicas se realizaron en 36 cadáveres adultos, 17 machos y 19 hembras, con masa corporal media de 2,5 kg y longitud cara-sacral media de 40 cm. Los cadáveres fueron obtenidos del sector de necropsia de la Universidad. Los especímenes tuvieron la arteria aorta torácica canalada, por la cual se inyectó solución de formaldehído al 10 %, seguida de látex coloreado. En los machos, el lobo izquierdo de la glándula tiroidea midió 1,40 x 0,40 x 0,01 cm y el derecho 1,36 x 0,56 x 0,01 cm; en las hembras, el lobo izquierdo midió 1,50 x 0,49 x 0,01 cm y el derecho 1,37 x 0,48 x 0,01cm. No hubo diferencia significativa (p> 0,05) entre las medias de las medidas entre machos y hembras, pero la extensión del lóbulo izquierdo de las hembras y la anchura del lóbulo derecho de los machos fueran significativamente mayores (p <0,05). La extremidad craneal de los lobos tiroideos se encontraba al nivel del cartílago cricoide en casi todos los especímenes. El extremo caudal presentó topografía más variable, desde el tercer hasta el décimo anillo traqueal, habiendo predominado al nivel del quinto anillo. Invariablemente, la irrigación arterial fue determinada por las arterias tiroideas izquierda y derecha, originadas de la arteria carótida común. Las anastomosis entre las arterias tiroideas fueron comunes. La constancia en las dimensiones y irrigación de la glándula tiroidea puede ser ventajosa en la elección del Coelho como modelo experimental para el estudio de esta glándula.