Mode B ultrasonography and abdominal Doppler in crab-eating-foxes ( Cerdocyon thous )

Abstract

Annually hundreds of crab-eating foxes (Cerdocyon thous) are referred to rehabilitation centers and zoos in Brazil. The ultrasonographic study of wildlife species is an important tool for a non-invasive and accurate anatomical description and provides important information for wildlife veterinary care. The aim of the present study was to determine the characteristics of the main abdominal organs as well as the vascular indexes of the abdominal aorta and renal arteries of crab-eating foxes (Cerdocyon thous) using mode B ultrasonography and Doppler ultrasonography, respectively. Ultrasonographic features of the main abdominal organs were described and slight differences were noticed between ultrasound imaging of abdominal organs of crab-eating foxes and other species. The bladder presented wall thickness of 12±0.01mm, with three defined layers. Both, the right and left kidneys presented corticomedullary ratio of 1:1 and similarly to the adrenals and the liver, they were homogeneous and hypoechoic compared to the spleen. The spleen was homogeneous and hyperechoic compared to the kidneys. The stomach presented 3 to 5 peristaltic movements per minute, wall thickness of 39±0.05mm and lumen and mucosa with hyperechoic and hypoechoic features, respectively. Small and large intestines presented 2 to 3 peristaltic movements per minute, wall thickness of 34±0.03mm and three defined layers with hyperechogenic (submucosa and serosa) and hypoechogenic (muscular) features. Ovaries of the female crab-eating fox were hypoechoic compared to the spleen and with heterogeneous parenchyma due to the presence of 2x2mm ovarian follicles. Prostates of the six males were regular and with a well defined boundary, with a homogeneous and hyperechoic parenchyma compared to the spleen. Vascular indexes of the abdominal aorta (PSV: 25.60±0.32cm/s; EDV: 6.96±1.68cm/s; PI: 1.15±0.07 e RI: 0.73±0.07) and right (PSV: 23.08±3.34cm/s; EDV: 9.33±2.36cm/s; PI: 1.01±0.65 e RI: 0.65±0.16) and left renal arteries (PSV: 23.74±3.94cm/s; EDV: 9.07±3.02cm/s; PI: 1.04±0.31 e RI: 0.64±0.10) were determined. Thus, conventional and Doppler ultrasonographic imaging provides basic information that can be used as reference for the species as well for other wild canids and it is a precise and non-invasive method that can be safely used to evaluate and diagnose abdominal injuries in these patients. RESUMO.-[Ultrassonografia abdominal modo B e Doppler em cachorros-do-mato (Cerdocyon thous).]O objetivo desse estudo foi descrever os achados ultrassonográficos convencionais dos principais órgãos abdominais e determinar com a utilização da ultrassonografia Doppler os índices vasculares da aorta abdominal e artérias renais em cachorros-do-mato (Cerdocyon thous). Foram avaliados nove cachorros-do-mato (Cerdocyon thous). Por meio da ultrassonografia convencional do abdômen dos animais, estudaram-se os achados ultrassonográficos normais e a biometria dos principais órgãos dessa cavidade como fígado, baço, bexiga, estômago, intestinos, adrenais, rins, ovários, prósta-ta e tec...

Abdominal B-mode and Doppler ultrasonography of chemically restrained agouti (Dasyprocta prymnolopha Wagler, 1831)

“…The ultrasound characteristics of the agouti stomach were similar to those described for pacas Cuniculus paca (Feliciano et al 2014) and wild dogs Cerdocyon thous (Heleno et al 2011). The stomach walls (0.16±0.05cm) and duodenum (0.3±0.15cm) of agoutis are thicker than those of the rabbit stomach (0.10±0.01cm) and duodenum (0.19±0.04cm) (Banzato et al 2015), but crab-eating foxes (0.39±0.05cm) (Silva et al 2014) and collared peccaries (0.42±0.28cm) (Peixoto et al 2012) have much thicker stomach walls than agoutis.…”

“…Regarding the renal morphometry, our measurements were within the maximum and minimum limits established by Banzato et al (2015) in rabbits of 2.8±0.34cm and 1.62±0.17cm for length and width, respectively, for the right kidney and 2.86±0.33cm and 1.72±0.19cm for the left kidney, length and width, respectively. The 1:1 cortex-medullar ratio observed in these wild rodents was individualized and preserved, as observed by Silva et al (2014) in crab-eating foxes (Cerdocyon thous) and by Feliciano et al (2014) in pacas (Cuniculus paca). However, a difference was observed in the cortex-medullar ratio compared with non-human primates (Cebus apella), that showed a 2:1 ratio (Alves et al 2007).…”

“…The agouti spleen presented thin and homogeneous echotexture, as observed by Silva et al (2014) in crab-eating foxes (Cerdocyon thous), Feliciano et al (2014) in pacas (Cuniculus paca) and Peixoto et al (2012) and wild pigs. In addition, greater echogenicity was observed compared with the left kidney, a fact also observed in crab-eating foxes (Cerdocyon thous) by Silva et al (2014) and in coatis (Nasua nasua) by (Ribeiro et al 2013).…”

“…The ultrasound assessment of the urinary system of this wild species showed many anatomic and topographic similarities with other domestic and wild animals. The urinary bladder presented location, shape and synthopia similar to the crab-eating fox Cerdocyon thous (Silva et al 2014), paca Cuniculus paca (Oliveira et al 2003, coati Nasua nasua (Ribeiro et al 2013) and cheetah Acinonyx jubatus (Carstens et al 2006). However, compared to a New World monkey species, the common marmoset Callithrix jacchus, the shape diverged, because in this non-human primate species the shape is multilobulate (Wagner & Kirberger 2005) that differs from the oval shape observed in the agoutis.…”

“…Previous ultrasonographic studies on wild species that discuss morphological aspects of abdominal structures include those on ant eaters Myrmecophaga tridactyla (Lopes et al 2015), crab-eating foxes Cerdocyon thous (Silva et al 2014), pacas Cuniculus paca (Oliveira et al 2003, agoutis Dasyprocta prymnolopha (Sousa et al 2012(Sousa et al , 2016(Sousa et al , 2017, coatis Nasua nasua (Ribeiro et al 2013), collared peccary Tayassu tajacu (Peixoto et al 2012), robust capuchin monkey Cebus apella (Alves et al 2007), cheetahs Acinonyx jubatus (Carstens et al 2006) and common marmosets Callithrix jacchus (Wagner & Kirberger 2005).…”