RESUMO
The agouti (Dasyprocta prymnolopha, Wagler 1831) is a wild rodent of great zootechnical potential, a fact that enables anatomical and morphological studies to support management actions with this animal. In this perspective, this study aimed to describe the anatomy and histology of the agouti stifle joint. Four adult agoutis were used, two females and two males. The animals were submitted to dissection and identification of the structures of the stifle joint. For light microscopy study, samples of the patellar ligament, cranial and caudal cruciate ligaments, medial and lateral collateral ligaments were used. Agouti has a highly congruent patellofemoral joint; elongated patella; medial and lateral fabellae at the proximal insertion of the gastrocnemius muscle; medial and lateral meniscus with lunula; in addition to the presence of the following ligament structures: patellar ligament, cranial and caudal cruciate ligaments, medial and lateral collateral ligaments, meniscofemoral ligament, caudal meniscal ligament of the medial meniscus, and medial and lateral cranial ligaments. The patellar ligament presents bundles of parallel collagen fibers with a straight path and coated fibroblasts; collateral and cruciate ligaments had loose and dense connective tissue, coated fibroblasts and collagen bundle undulations, the latter most expressive in the caudal cruciate ligament. Thus, except for the shape and angulation of the stifle, which allows specific movements, the agouti stifle has structures analogous to that of other rodents and domestic animals.
Assuntos
Dasyproctidae , Joelho de Quadrúpedes , Animais , Dissecação , Feminino , MasculinoRESUMO
Background: The species Dasyprocta prymnolopha is a wild rodent with a geographic distribution that extends from Mexico to South America, including Brazil. Agouti has been the subject of morphophysiological research, but data on the cardiovascular system remains limited. Therefore, the objective was to describe the macroscopic and microscopic morphology, including the study of the cardiac and coronary system syntopy of the species D. prymnolopha. Materials, Methods & Results: Twelve Dasyprocta primnolopha adults were used, 6 males and 6 females. Topographic analysis of the heart was evaluated in situ, with subsequent measurement, anatomovascular description and macroscopic study of cardiac and coronary vascularization. A microscopic investigation and identification of structural cardiac aspects were also carried out in adult agoutis, the biological samples of the heart were submitted to histological techniques and stained with Hematoxylin and Eosin and Masson's Trichrome. The heart is located between the end of the 2nd and the beginning of the 5th intercostal space, with the apex reaching the 6th space. It presents the presence of 2 ligaments: phrenopericardium and sternopericardium. The right atrioventricular valve is composed of 2 cusps, the parietal and the septal, with variations within the same species for 3 cusps. Projections that interconnect the papillary muscles with each other were observed. In the left ventricle there are variations in the number of papillary muscles (range 2 to 4). In the region of the aortic valve, 5 ostia were observed in the left aortic sinus in all animals. The coronary circulation has a predominantly left distribution. Histologically, the heart consists of 3 main layers: endocardium, myocardium, and epicardium. The cusp valves of the atrioventricular openings are composed of endocardial folds that contain a central plate of dense connective tissue, and inserted in this cardiac musculature was observed the cardiac skeleton, with its fibrous ring consisting of collagen and elastic fibers that surrounds the atrioventricular opening. Discussion: Cardiac assessment in wild animals is challenging, as in-depth knowledge of the morphology of the cardiovascular system is required for the use of diagnostic tools. In this first anatomical study of the heart, this organ presents syntopy with those of other rodents, but the topography may vary in individuals of the same species, which may be related to the accentuated vertebral curve. The phrenopericardial and sternopericardial ligaments were observed in this research, although there are no reports in other species of Dasyprocta sp. The arrangement of the arteries has, as a particularity, the larger left atrium in relation to the heart/atrium size ratio when compared to other domestic species, covering the left coronary sinus until it reaches the left atrial surface. In the agouti, it was observed that the vascularization is left, with the left coronary artery giving rise to both the paraconal and subsinuous interventricular branch, a fact found in animals such as ruminants, dogs. In the histological observations of the present study, the heart was similar to that of other mammals. Our data reveal morphological characteristics similar to those of other mammals, but with very expressive characteristics that differ even within the species. It is important to generate new information to elucidate cardiac and coronary diagnostic analyses, which can be extended to different species.
Assuntos
Animais , Sistema Cardiovascular/anatomia & histologia , Vasos Coronários/anatomia & histologia , Dasyproctidae/anatomia & histologia , Amarelo de Eosina-(YS) , Técnicas de Imagem Cardíaca/veterináriaRESUMO
The arterial vascularization of the male genital system of agouti (Dasyprocta prymnolopha) wasanalysed using one male adults from 'Núcleo de Estudos e Preservação de Animais Silvestres from UniversidadeFederal do Piauí. Red Neoprene latex was injected through the hearts left ventricle, the sample was fixed in10% formaldehyde solution and arteries were dissected. The blood vessels were photographed using digitalcamera, Sony DSC-H10. The testicular artery, originated from the ventral portion of the abdominal aorta,between the renal arteries and caudal mesenteric arteries, is responsible for the vascularization of the testes, vasdeferens and epididymis. The penile artery, originated from the internal pudendal artery, performs the arterialsupply for penis. The arterial vascularization of the reproductive organs of agouti is similar to those ofcarnivores (dogs), rodent nutria and domestic rabbits.
Assuntos
Masculino , Animais , Dasyproctidae/anatomia & histologia , Dasyproctidae/fisiologia , Genitália Masculina , ArtériasRESUMO
The arterial vascularization of the male genital system of agouti (Dasyprocta prymnolopha) wasanalysed using one male adults from 'Núcleo de Estudos e Preservação de Animais Silvestres from UniversidadeFederal do Piauí. Red Neoprene latex was injected through the hearts left ventricle, the sample was fixed in10% formaldehyde solution and arteries were dissected. The blood vessels were photographed using digitalcamera, Sony DSC-H10. The testicular artery, originated from the ventral portion of the abdominal aorta,between the renal arteries and caudal mesenteric arteries, is responsible for the vascularization of the testes, vasdeferens and epididymis. The penile artery, originated from the internal pudendal artery, performs the arterialsupply for penis. The arterial vascularization of the reproductive organs of agouti is similar to those ofcarnivores (dogs), rodent nutria and domestic rabbits.(AU)
Assuntos
Animais , Masculino , Dasyproctidae/anatomia & histologia , Dasyproctidae/fisiologia , Genitália Masculina , ArtériasRESUMO
The gestation period in agoutis can range from 104 to 120 days. Knowledge regarding the morphological characteristics of embryos and fetuses is important as a base for studies in reproduction biotechnology, such as in vitro fertilization, embryo transfer and helps in determining congenital anomalies during the development phase. Thus, given the importance and lack of information about agouti embryology, the objective of this study was to characterize the external morphology and define the biometry of embryos and fetuses, at different days of development. Nine females were submitted to daily colpocytology to identify the estrus, confirm mating and identify day zero of the gestation. When the mating was confirmed they were weighed, underwent abdominal ultrasonography and surgery was conducted on the females at the gestational ages of 25, 30, 35, 40, 45, 50, 75 and 100 days. Sixteen embryos/fetuses were weighed and measured. Agouti embryos at 25 days after mating are "C" shaped, with primitive structures, 0.4±0.01cm crown-rump and weighed 0.06±0.01g; at 30 days after mating the crown-rump was 0.95±0.07cm and weighed 0.28±0.00g; at 35 days after mating the crown-rump was 155±0.07cm and weighed 0.38±0.01g; at 40 days after mating the crown-rump was 2.25±0.21cm and weighed 1.25±0.07g; at 45 days after mating the crown-rump was 3.45±0.35cm and weighed 2.75±0.64g; at 50 days after mating the crown-rump was 5.0±0.3cm and weighed 7.01±2.6g; at 75 days after mating, the skin was dark, the crown-rump was 10.0±0.14cm and weighed 55.2±0.07g. At 100 days after mating, the crown-rump was 13.8±0.49cm and fetuses weighed 136.7±9.40g. Based on the morphological data assessed the embryo and fetus age could be assessed and the size and average weight of agouti embryos was established.