Organogenesis and foetal haemodynamics during the normal gestation of healthy black‐rumped agoutis (Dasyprocta prymnolopha, Wagler, 1831) bred in captivity

Abstract

The objective of this study was to define the patterns of organogenesis and foetal haemodynamics during the normal gestation of healthy agoutis (Dasyprocta prymnolopha) kept in captivity. Thirty pregnant agoutis that ranged in size from small to medium and weighed between 2.5 and 3 kg underwent B-mode and Doppler ultrasonography for the biometric evaluation of the foetal organs. The foetal aortic blood flow proved to be predominantly systolic, and the measured flow velocity was 78.89 ± 2.95 cm/s, with a maximum pressure gradient of 2.12 ± 0.27 mmHg. The liver was characterized by its large volume, occupying the entire cranial aspect of the abdominal cavity, and it was associated cranially with the diaphragm and caudally with the stomach. The flow velocity in the portal vein was estimated to equal 12.17 ± 2.37 cm/s, with a resistivity index of 0.82 ± 0.05. The gallbladder was centrally located and protruded cranially towards the diaphragm. The spleen was visualized as an elongated structure with tapered cranial and caudal extremities, and the foetal kidneys were visualized bilaterally in the retroperitoneal region, with the right kidney positioned slightly more cranially than the left. The morphological characterization and hemodynamic analysis of the foetal organs of black-rumped agoutis via B-mode and Doppler ultrasonography allow determination of the vascular network and of reference values for the blood flow required for perfusing the anatomical elements essential for maintaining the viability of foetuses at different gestational ages.

B-mode and Doppler ultrasonography of abdominal structures of the peccary (Tayassu tajacu, Linnaeus 1758)

“…The ultrasound evaluations of the abdominal structures of the studied peccaries were performed in planes cut along the longitudinal, transverse, and dorsal axes (Barberet et al, 2008). Although the animals were fasted from food for 12 hours and water for 3 hours, the difficulty of emptying the gastrointestinal tract of wild animals has been recognized (Sousa et al, 2012). This difficulty is a limiting factor in the adequate preparation for ultrasonographic examinations, with the main implication being the amount of gas found in the intestinal loops, as observed in this study.…”

“…Ultrasonography has been increasingly used in the routine diagnosis of pathological processes in wild species, especially as it is a noninvasive method and allows real-time characterization of abdominal and thoracic structures in these animals (Cruz and Freitas, 2001). A number of studies have addressed the morphological aspects of abdominal structures in wild species such as giant anteaters (Myrmecophaga tridactyla) (Lopes et al, 2015), forest foxes (Cerdocyon thous) (Silva et al, 2014), lowland pacas (Cuniculus paca) (Oliveira et al, 2003(Oliveira et al, , 2007Feliciano et al, 2014), agouti (Dasyprocta prymnolopha) (Sousa et al, 2012(Sousa et al, , 2016(Sousa et al, , 2017, peccaries (Tayassu tajacu) (Peixoto et al, 2012), coatis (Nasua nasua) (Ribeiro et al, 2013), tufted capuchin monkeys (Cebus apella) (Alves et al, 2007), cheetahs (Acinonyx jubatus) (Carstens et al, 2006), and white-tufted-ear marmosets (Callithrix jacchus) (Wagner and Kirberger, 2005).…”

Reproduction in agouti (Dasyprocta spp.): A review of reproductive physiology for developing assisted reproductive techniques

“…The first uterine morphological changes were observed on day 9 as an anechoic spherical structure, with slightly hyperechoic margins, and gestational sac was observed at only around 76 days after mating. In a recent study with the same species, B-mode ultrasonography associated with Doppler allowed the evaluation of the vascular network and determination of the reference values for blood flow necessary to maintain fetal viability at different gestational ages (Sousa et al, 2017). In addition, morphogenetic analysis of the fetuses of D. leporina from 30 to 100 days revealed stages of embryonic and fetal development , demonstrating the progress of speciesoriented studies.…”

Abdominal aortic branches of red‐rumped agouti (Dasyprocta leporina Linnaeus, 1758)

“…The red‐rumped agouti ( Dasyprocta leporina ) is a medium‐sized rodent belonging to the Dasyproctidae family, restricted to the American continent with a diet based on fruits, leaves and seeds (Silvius & Fragoso, 2006). Due to this dietary habit, the red‐rumped agouti plays an important ecological role, acting as a seed disperser, with some plant species depending almost exclusively on this rodent (Sousa et al, 2017). Moreover, it is also socioeconomically important as a protein source (Menezes et al, 2017).…”