Prenatal post-implantation development of collared peccaries (Pecari tajacu Linnaeus, 1758).

Given the importance of information on intrauterine development in diagnosing anomalies in the gestational development of the species for the development of assisted reproduction technologies as well as understanding the autonomy and responsiveness of the newborn, the aim of the present study was to describe the external morphology of collared peccary conceptuses. For this study, two conceptuses were used per gestational age of 25-120 days post-copulation (dpc) and neonates with 145 dpc, totalling 22 animals. Females were euthanised, and embryos/foetuses were examined, measured, and photographed. During the first third of the gestational period (25-50 dpc, n = 8), a marked body curvature, brain vesicles, somites, internal organs, placid lens, auricular protrusion and limb buds are noted. In the second third of the gestational period (51-100 dpc, n = 10), foetuses lose their body curvature, displaying greater anatomical definition, including skeletal, external ears, nostrils, eyelids and tactile hair formation and cranial suture closure. In addition, dorsal scent gland and genital tubercle differentiation were visualized at 50 days post-copulation. In the third of the gestational period (101-145 dpc, n = 4), the organs become completely formed, alongside skin darkening, eyelid opening, dental eruption, dorsal odorous gland development, sexual organ externalization, and fanero attachment development. These data allowed for the construction of a prenatal growth curve, providing comparative anatomy information for ungulates and further contributing towards rational reproductive management and reproductive biotechnologies for this species.

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

Understanding the cardiovascular system is fundamental in diagnosing pathologies and interpreting exams, such as contrast radiographs. In this context, the present study describes the collateral abdominal aorta artery branches of red-rumped agouti. Ten red-rumped agoutis, six males and four females, were assessed. The vascular system was perfused with Neoprene 450 latex coloured with a yellow pigment, dissected and analysed. Three euthanized animals were perfused with a barium sulfate solution (1 g mL-1 ) associated with latex Neoprene 450 at a 1:3 ratio to obtain contrast-enhanced radiographs. The abdominal aorta emitted the celiac artery, which in turn originated the left gastric, hepatic and splenic arteries. The second collateral branch comprised the cranial mesenteric artery, followed by the renal arteries, which emitted the adrenal arteries, with the caudal emergence of the gonadal arteries. The caudal mesenteric artery appeared in a caudal direction. The abdominal aorta divided after reaching the pelvic cavity entrance, originating the right and left common iliac arteries. Before its bifurcation, the abdominal aorta dorsocaudally emitted its last collateral branch, the median sacral artery. The collateral branches of the aorta, therefore, resemble previously described rodent patterns, with few variations.

Extraembryonic membrane morphology in greater rheas (Rhea americana americana Linnaeus, 1758).

The greater rhea, Rhea americana, is a wild ratite of high scientific importance and significant and zootechnical value, especially considering the current development state of Brazilian poultry production, where research aimed at increasing the productivity of these animals has become extremely relevant. Studies concerning fetal attachments and embryonic development are paramount, as they can provide essential information concerning reproductive and nutritional animal management. However, a lack of information on greater rhea fetal morphology is noted. Therefore, the aim of the present study was to establish a standard model for fetal attachments in this species. Greater rhea eggs were incubated from 0 to 36 days, and macroscopic and microscopic embryonic attachment characterizations were performed. Histologically, all embryonic annexes exhibit germ layers, namely the ectoderm (outer layer), mesoderm (middle layer) and endoderm (inner layer). The findings indicate that greater rhea development patterns are similar to other birds.

Abortion and congenital transmission of Trypanosoma vivax in goats and ewes in semiarid northeastern Brazil.

The main effects of trypanosomosis in Brazil are related to reproductive alterations. In this context, the present study aimed to report the occurrence of abortions in goats and sheeps in the semiarid region of Northeastern Brazil, associated with Trypanosoma vivax. Trypomastigotes forms visualized by Buffy coat technique (BCT) method in 68.7% of the goats and 50.0% of the ewes that aborted. PCR identified that 100% of the goats and ewes that aborted were infected with T. vivax. The goats and ewes that aborted showed high parasitemia and developed clinical signs of trypanosomosis. The presence of T. vivax DNA was identified in the blood of fetuses by the PCR technique, proving infection by T. vivax in aborted fetuses, as well as confirming the congenital transmission of the parasite.

Collateral aortic branches in the collared peccary (Pecari tajacu Linnaeus, 1758).

The determination of arterial vascular distribution patterns can contribute to more detailed knowledge on arterial systems. In this context, the aim of the present study was to describe the collateral aortic branches in the collared peccary, aiming to define a standard model for this species, providing information through comparative anatomy for analysis of some evolutionary aspects of the order Artiodactyla. Ten young male animals were employed. The vascular system was washed with a saline solution and then perfused with Neoprene 450 latex coloured with red or yellow pigment, followed by collateral aorta branch dissections and analyses. The contrasted digital radiography technique was applied to two animals, which were initially perfused with a barium sulphate solution (1 g/ml) and Neoprene 450 latex at a 1:3 ratio, and subsequently, the digital radiographic examination was performed. The aortic arch of the collared peccary emitted the brachiocephalic trunk and the left subclavian artery, while eight symmetric pairs of dorsal intercostal arteries originated from the thoracic aorta. The abdominal aorta, in turn, exhibited the celiac, cranial mesenteric, renal, caudal mesenteric, testicular, external iliac, internal iliac and sacral arteries as the collateral branches in all studied animals. Therefore, no relevant variations were observed regarding the arrangement of the arterial distribution of the aorta, thus suggesting a static standard model in the collared peccary.