Infectious and Non-Infectious Diseases in Manatees in Brazil

Background: Antillean manatee (Trichechus manatus) and Amazonian manatee (Trichechus inunguis) are the two species of manatees that occur in Brazil, and both are endangered. Studies on manatee disease in Brazil were previously based mainly on Florida manatees. In recent years, these studies have increased in Brazil. Thus, the objective was to carry out a survey of the publications of infectious and non-infectious diseases in the two species of manatees that occur in the country, to assist in the identification of threats to the species and in the health assessment of manatees in the country.Review: Regarding infectious and contagious diseases, parasites have affected both species of manatees in Brazil, such as Pulmonicola cochleotrema in wild T. manatus, Toxoplasma gondii in both species, and Cryptosporidium spp. also in both species, this being an important agent of zoonotic character. Giardia sp., another zoonotic parasite, has also been reported in both species of manatees in Brazil. Mycotic lesions caused by B. hawaiiensis have been described in calves of T. manatus in captivity. Meanwhile, Candida sp., Trichosporon sp., Rhodotorula sp., and Cryptococcus sp. have been identified in T. inunguis. Studies on viruses in manatees are still not widespread compared to other species; however, it has been verified that rotavirus is present in T. manatus in captivity. In studies carried out to identify bacteria in T. manatus, the following bacteria were isolated: Arizona sp., Bacillus sp., Corynebacterium equi, Corynebacterium pseudodiphteriticum, Corinebacterium sp., Edwasiella tarda, Enterobacter aerogenes, Enterobacter agglomerans, Enterobacter sakasakii, Escherichia coli, Leptospira spp., Proteus sp., Proteus vulgaris, Providencia rettgeri, Pseudomonas aeruginosa, Salmonella spp., Serratia marcescens, Staphylococcus sp., Staphylococcus aureus, Staphylococcus coagulase-negativa, Stenotrophomonas maltophilia, Streptococcus sp., and Streptococcus viridans. Regarding noninfectious diseases, food-related diseases stand out, where gastrointestinal complications in manatees and obesity in animals in captivity are among the highest occurrences. Intestinal tympanism was reported in a T. inunguis calf, causing death of the animal. Pollution and contamination have also been a concern for the health of these animals. In studies carried out with T. manatus in Paraíba state, accumulation of heavy metals in the animals was verified, possibly originating from sugarcane farms in the region. The ingestion of garbage has also been one of the greatest threats to the health of manatees, where it was registered as a possible cause of death of T. inunguis in Amazonas state. Regarding congenital diseases, although rare in manatees, two calves of T. manatus in Ceará state have been described as having congenital malformations in the heart and brain, without a well-defined etiology. Trauma has been affecting both species; in Brazil, 17.3% of manatees reintroduced by 2018 showed evidence of collisions with vessels. Hunting for T. inunguis still occurs frequently, which has been greatly reduced for T. manatus.Conclusion: Pathogens and other factors that affect manatees have a potential impact on both species. Some of the identified agents have a zoonotic potential and, therefore, are also public health issues. This survey demonstrates that the need for incentives for studies on health assessment and pathogens in these species, both in the wild and in captivity, should be encouraged

ORIGEM E DISTRIBUIÇÃO DA ARTÉRIA CELÍACA EM PREÁS (Galea spixii Wagler, 1831)

Para o estudo foram utilizados 20 animais, que estavam em freezer no Centro de Multiplicação de Animais Silvestres (CEMAS/UFERSA). Os animais foram descongelados, a cavidade abdominal aberta e a aorta torácica canulada no sentido caudal para injeção de solução de látex Neoprene 650 corado de vermelho e, em seguida, fixados em solução de formaldeído a 10%, por um período mínimo de 48 horas, para que pudessem ser dissecados, fotografados e os resultados analisados. A artéria celíaca originou-se da aorta abdominal e emitiu as artérias gástrica esquerda, lienal e esplênica. A artéria gástrica esquerda emitiu de dois a três ramos à região da curvatura menor do estômago. A artéria lienal emitiu quatro ramos ao parênquima do baço, de seis a doze ramos pancreáticos e a artéria gastroepiplóica esquerda. A artéria hepática emitiu de um a dois ramos pancreáticos e bifurcou-se em um curto tronco formado pelas artérias gástrica direita e hepática própria e ainda na artéria gastroduodenal, que originava a pancreaticoduodenal cranial e gastroepiplóica direita. O comportamento de trifurcação da artéria celíaca do preá assemelha-se ao encontrado em roedores, como o nutria, a cutia, o hamster e os ratos, o que sugere que este seja o padrão para a ordem. Palavras-chave: aorta abdominal; aparelho digestório; Galea spixii; roedor; vascularização

Collateral Arteries of the Aortic Arch in Mongolian Gerbil (Meriones unguiculatus)

Background: Gerbils (Meriones unguiculatus) are rodents belonging to the Muridae family. Recently, breeding of this species as pets has increased significantly. Animal models are being investigated to study diseases related to the human aortic arch. Despite the importance of the aortic arch in maintaining homeostasis, there is limited data available regarding its morphology in gerbils. This study was performed with the objective of describing the collateral branches of the aortic arch in this animal to establish a standard model and thus contribute to future research on cardiovascular diseases in humans.Materials, Methods & Results: This study used 20 male specimens from previous studies that were frozen and stored at the Laboratory of Veterinary Anatomy of the Federal Rural University of the Semi-Arid Region. After thawing the animals, the thoracic cavity was opened for aortic cannulation. The vascular system was washed using saline solution and Neoprene latex stained with red pigment was injected. Subsequently, the animals were fixed in 10% formaldehyde and were dissected and analyzed 72 h later. The arrangement of the collateral branches of the aortic arch in gerbils was analyzed in all animals. The brachiocephalic trunk, the left common carotid, and the left subclavian artery were observed to originate as collateral branches. The brachiocephalic trunk bifurcated into the right common carotid and the right subclavian arteries. The right and the left subclavian arteries branched into the vertebral artery, the internal thoracic artery, the superficial cervical artery, the costocervical trunk, and the axillary artery.Discussion: Several studies reported in the literature describe the collateral branches of the aortic arch in domestic and wild mammalian species. These studies examined the main arteries that originate directly from the aortic arch and their respective branches, and classified the different anatomical variants of the aortic arch in each species. Three different arrangements have been commonly described. The first type corresponds only to the brachiocephalic artery originating from the aortic arch. The right and the left common carotid arteries and the right and the left subclavian arteries originate from this brachiocephalic artery. This type has already been described in the laboratory rat, catingueiro-deer, cattle, and horses. The second type is characterized by the presence of 2 arteries - the brachiocephalic trunk and the left subclavian artery. The right and the left common carotid arteries and the right subclavian artery originate from the brachiocephalic trunk. This arrangement has been reported in most species already studied such as rodents including the paca, chinchilla, guinea pig, mocó, nutria and the preá. The third type of vascular arrangement is observed in the gerbil. In this species, 3 collateral arteries originate from the aortic arch (the brachiocephalic trunk, the left common carotid, and the left subclavian artery). The right common carotid and the right subclavian artery originate from the brachiocephalic trunk. This vascular model has been described in the manatee, in humans, mice, sauim, and the monkey-nail. Thus, we concluded that the branching pattern of the aortic arch of the gerbil was characterized by the brachiocephalic trunk, the left common carotid, and the left subclavian artery, as has been described in mice, the manatee, monkey-nail, sauim, and humans. Based on these morphological characteristics, gerbils could serve as potential experimental models to study diseases related to the human aortic arch

Morphology of the cardiovascular system in greater rhea (Rhea americana americana Linnaeus, 1758)

Greater rheas have been the subject of scientific studies in the various areas of veterinary and biology in order to obtain essential information for their captivity management. The aim of this study was to describe the morphology of the greater rhea heart. The 20 animals were incised in sagittal plane, then fixed in 3.7% formaldehyde and dissected after 72 h. In addition, samples from the cardiovascular system were collected, processed for hematoxylin-eosin and Gomori Trichrome Staining. The heart is conical in shape, dark red when fresh and is located between the hepatic lobes. It has two atria and two ventricles, and four valves (left and right atrioventricular, aortic and pulmonary). The aorta and pulmonary trunk emerge at the heart base, while the ostia of the cranial and caudal vena cava emerged from the right atrium and the right and left pulmonary veins and the left coronary vein from the left atrium. From the aorta artery, the right and left coronary arteries arose, which originated, respectively, the superficial and conal branches and the profuse, left ventricular and superficial branches, being responsible for the irrigation of the heart. Microscopically the heart was constituted by simple pavement epithelium, rich in loose connective tissue. The aorta and pulmonary arteries were composed of the intima, middle and adventitial tunics. Thus, it is concluded that the morphological findings of greater rhea resemble those described for other birds such as ostrich and Gallus gallus domesticus.Greater rheas (Rhea americana americana) have been the subject of scientific studies in the various areas of veterinary and biology in order to obtain essential information for their captivity management. The aim of this study was to describe the morphology of the greater rhea heart. The 20 animals were incised in sagittal plane, then fixed in 10% formaldehyde and dissected after 72 h. In addition, samples from the cardiovascular system were collected, processed for hematoxylin-eosin and Gomori Trichrome Staining. The heart is conical in shape, dark red when fresh and is located between the hepatic lobes. It has two atria and two ventricles, and four valves (left and right atrioventricular, aortic and pulmonary semilunar). The aorta and pulmonary trunk emerge at the heart base, while the ostia of the cranial and caudal vena cava emerged from the right atrium and the right and left pulmonary veins and the left coronary vein from the left atrium. From the aorta artery, the right and left coronary arteries arose, which originated, respectively, the superficial and conal branches and the profuse, left ventricular and superficial branches, being responsible for the irrigation of the heart. Microscopically the heart was constituted by simple pavement epithelium, rich in loose connective tissue. The aorta and pulmonary arteries were composed of the intima, middle and adventitial tunics. Thus, it is concluded that the morphological findings of greater rhea resemble those described for other birds such as ostrich and chicken

Pyothorax in Antillean Manatee (Trichechus manatus) in Brazil

Background: Manatees are the most endangered aquatic mammals in Brazil. The current conservation scenario, together with their biological characteristics, raises concern with the future of this species. Pyothorax, also known as septic pleural effusion or pleural empyema, is characterized by the accumulation of a septic purulent exudate within the pleural space. Although this infection often has a multifactorial etiology, it is most commonly associated with respiratory tract disorders and trauma. Here, we report a case of pyothorax in a Antillean manatee (Trichechus manatus) held in captivity for acclimatization in Brazil.Case: A young, male Antillean manatee, aged 4 years and 11 months, measuring 227 cm in total length, and weighing 258 kg was held in captivity for acclimatization (natural environment) in Porto de Pedras in the State of Alagoas, Brazil. The animal died in February 2013 and was sent for necropsy at the CMA/ICMBio laboratory. The study was developed with authorisation from the Ethics Committee on Animal Use (License number 020/2009) and under the license SISBIO/ICMBio number 20685-1. Externally, the carcass of the animal showed swelling and bulging of the right antimere and purulent secretion from the right nostril. After external examination, a window was opened in the layers of skin, fat, and muscles from the level of the anus to the navel. Subsequently, the abdominal cavity was opened for inspecting the internal organs. The subcutaneous muscles had a slightly friable, swollen, and pale texture, in addition to petechial hemorrhage, suffusions, and marked edema of the subcutaneous tissue. The right hemidiaphragm was elevated, filling the abdominal and thoracic spaces. Depending on the elevation, all organs were moved to the left antimere. After dissecting the surrounding structures and analyzing the causes for the increase in volume, it was observed that the right lung formed a structure containing a large amount of purulent exudate, which was delimited by the right hemidiaphragm. It had a length of 111 cm, width of 40 cm, and wingspan of 137 cm, starting from the first thoracic rib to the last lumbar rib, near the peduncle region. After making an incision in the right hemidiaphragm and visceral pleura, approximately 70 L of purulent exudate and caseous material were removed. Since the right lung was severely damaged, visualizing the pulmonary parenchyma was not possible, and only remains of the main right bronchus could be seen.Discussion: Domestic species, such as dogs and cats, when affected by pleural empyema, usually have a restrictive breathing pattern (shallow and rapid breaths) and fever. Interpreting the clinical signs may be difficult for manatees because of their slow metabolism. In the United States, 44 (6%) cases of pleural empyema were recorded in manatees from a total of 731 animals evaluated, and shock with boats was determined as the primary cause. In the present animal, no signs of bone fractures were found, suggesting that the infection may have been caused by the use of an orogastric tube or even acquired in the environment prepared for acclimation. Based on the pathognomonic macroscopic findings, one can conclude that the animal had a characteristic clinical picture of pleural empyema (pyothorax) associated with an infection of unknown origin. This situation resulted in complete degeneration of the right lung and massive thoracic and abdominal distensions, resulting in decreased expansion capacity of the left lung, making breathing impossible, thus leading to death

Vascularização arterial da base do encéfalo de cutias (Dasyprocta aguti Linnaeus, 1766)

The agouti, a rodent that is geographically distributed throughout South America, is greatly valued for its meat. This paper describes the arterial vascularization of the base of the agouti’s brain, characterizing behavior, and arterial origin and distribution. Ten animals from the Center for the Multiplication of Wild Animals (CEMAS/UFERSA) were used and the study was approved by SISBIO (report number 32413- 1) and the Ethics Committee on Animal Use (CEUA/UFERSA) (protocol 02/2010). After euthanasia, the animals were incised in the thoracic cavity by an injection of red-stained Neoprene latex 650 and the skulls were subsequently opened. The brains were extracted from the skulls for ventral surface analysis and then fixed in an aqueous 10% formaldehyde solution. The agouti’s arterial vascularization of the brain has two main components, namely the carotid and vertebrobasilar systems. The agouti’s carotid system accounts for vascularization of almost the entire forebrain, while the vertebrobasilar system accounts for vascularization of almost the entire posterior brain (medulla oblongata, pyramid, trapezoid body, cerebellum, bridge, and part of the third caudal section of the forebrain) through the caudal cerebral arteries originating from the terminal branches of the basilar artery. The main arteries on the brain surface include the basilar artery, which is unique, and the arterial pairs, specifically the vertebral arteries, cerebellar caudal arteries, trigeminal artery, rostral cerebellar artery, basilar terminal branch artery, cerebral caudal artery, communicating caudal branch of the cerebral carotid artery, cerebral carotid artery, communicating branch rostral cerebral carotid artery, choroidal rostral artery, medial branch of the communicating branch rostral artery, internal ophthalmic artery, middle cerebral artery, and rostral cerebral artery.A cutia é um roedor, que se distribui geograficamente por quase toda América Latina, sendo apreciada pelo sabor da sua carne. Neste trabalho objetivou-se descrever a vascularização arterial da base do encéfalo de cutias, caracterizando o comportamento, origem e distribuição das artérias componentes. Foram utilizados 10 animais do Centro de Multiplicação de Animais Silvestres (CEMAS/UFERSA), pesquisa aprovada pela Comissão de Ética no Uso de Animais (CEUA/ UFERSA- n° 02/2010) e pelo SISBIO (N°32413-1). Após eutanásia, os animais foram incisados na cavidade torácica para injeção de Neoprene látex 650 corado na cor vermelha e posterior abertura da calota craniana. Os encéfalos foram extraídos do crânio para análise da sua face ventral e logo fixados em solução aquosa de formaldeído a 10%. A vascularização arterial do encéfalo da cutia apresenta dois componentes principais, o sistema carótico e o vértebro-basilar. O sistema carótico na cutia é responsável pela vascularização do cérebro anterior em quase sua totalidade. O sistema vértebro-basilar é responsável pela vascularização do cérebro posterior (medula oblonga, pirâmide, corpo trapezóide, o cerebelo e ponte e parte do terço caudal do cérebro anterior), através das artérias cerebrais caudais, originárias dos ramos terminais da artéria basilar. As principais artérias presentes na superfície do encéfalo incluem a basilar que é ímpar, e as pares: artérias vertebrais, cerebelar caudal, trigemial, cerebelar rostral, ramo terminal da basilar, cerebral caudal, ramo comunicante caudal da carótida cerebral, carótida cerebral, ramo comunicante rostral da carótida cerebral, corióidearostral, ramo medial do ramo comunicante rostral, oftálmica interna, cerebral média e artéria cerebral rostral

Plexo lombossacral da cutia (Dasyprocta leporina Linnaeus, 1758) (Rodentia: Caviidae)

The red-rumped agouti is a small-sized wild rodent, belonging to the Dasyproctidae family, with great zootechnical potential, and it adapts well to captivity. In order to contribute to the species biology, this study describes the origin of the nerves forming the lumbosacral plexus. Twelve animals (six males and six females) were used, from previous experiments. The animals were fixed in a 10% formaldehyde aqueous solution and eviscerated after 72 hours. Then, the major and minor psoas muscles were retracted, exposing the nerves forming the plexus. Cotton soaked with 20-volume hydrogen peroxide was placed on these nerves, remaining for 12 hours straight for bleaching and subsequent dissection. The topographical relations of the lumbosacral plexus were grouped into tables and arranged in terms of simple percentage. In 7 cases (58.34%), the lumbosacral plexus in the red-rumped agouti stemmed from the ventral roots of the last 4 lumbar nerves and the first 3 sacral nerves (Type I – L4-S3), in 4 animals (33.33%) it stemmed from L5-S3 (Type II), and in 1 case (8.33%) it stemmed from L5-S4 (Type III). The nerves participating of the lumbosacral plexus in the red-rumped agouti were: lateral femoral cutaneous, genitofemoral, femoral, obturator, sciatic, cranial gluteal, caudal gluteal, and pudendal nerve. The origin of the lumbosacral plexus and the spinal nerves making up this plexus in red-rumped agoutis were similar to that described in other rodents, such as rock cavy, lowland paca and spix's yellow-toothed cavy.A cutia é um roedor silvestre, de pequeno porte pertencente à família Dasyproctidae, com grande potencial zootécnico e que se adapta bem ao cativeiro. De forma a contribuir acerca da biologia da espécie, objetivou-se descrever a origem dos nervos que formam o plexo lombossacral. Foram utilizados 12 animais (6 machos e 6 fêmeas), provenientes de experimentos anteriores. Os animais foram fixados em solução aquosa de formaldeído a 10% e após 72 horas, eviscerados. Em seguida os músculos psoas maior e menor foram rebatidos, expondo-se os nervos que formavam o plexo. Sobre estes nervos foi colocado algodão embebido com peróxido de hidrogênio a 20 volumes, permanecendo por 12 horas seguidas para clareamento e consequente dissecação. As relações topográficas do plexo lombossacral agrupadas em tabelas em forma de porcentagem simples. O plexo lombossacral da cutia originou-se em sete casos (58,34%) a partir das raízes ventrais dos quatro últimos nervos lombares e três primeiros nervos sacrais (Tipo I – L4-S3), em quatro animais (33,33%) a partir de L5-S3 (Tipo II) e um caso (8,33%) a partir de L5-S4 (Tipo III).Os nervos que participaram do plexo lombossacral da cutia foram: cutâneo femoral lateral, genitofemoral, femoral, obturatório, isquiático, glúteo cranial, glúteo caudal e nervo pudendo. A origem do plexo lombossacral e os nervos espinhais constituintes deste plexo em cutias foram semelhantes ao descrito em alguns roedores como mocó, paca e preá