Morphology of the male reproductive tract of Eira barbara.

Eira barbara, popularly known as irara, is a medium-sized carnivore member of the Mustelidae family. Despite its important role in the ecosystems in which its lives, data on the internal morphology of E. barbara remains scarce. Therefore, this study aimed to provide knowledge regarding the anatomy of the male reproductive system of this species to improve understanding of its reproduction to inform its conservation. We studied seven specimens who had died after being run over. The specimens were dissected for the evaluation of the reproductive system, which comprised a globular scrotum; a small pendulum covered with light-coloured hair; a pair of testicles of firm consistency and ellipsoid shape and suspended in the scrotum by the spermatic cord; a paired duct system; an ampoule of the deferens duct and prostate constituting the set of attached glands; a urethra divided into pelvic and penile portions; a penis with a baculum having a novel "C" shaped apex; and a prepuce. Microscopically, the testicular parenchyma consisted of seminiferous tubules separated by intertubular spaces formed by loose connective tissue, fibrocytes, Leydig cells, and blood and lymph vessels. The epididymis was surrounded by a capsule of dense connective tissue and extended to form septa. The baculum was microscopically classified as a compact bone containing several bony lamellae with osteocytes and osteoblasts. The macro and microscopic findings were generally similar to those of domestic carnivores, with some notable differences.

Morphological diagnosis of Setaria labiatopapillosa in domestic bovids from Marajó Island, Brazil.

The genus Setaria is known worldwide for parasiting wild and domestic mammals, with 43 species registered, of which five occur in the American continent. The objective of this study was to characterize the occurrence, morphology and morphometry of S. labiatopapillosa in B. taurus and B. bubalis in Marajó Island, Brazil. Carcass inspections of 420 cattle were carried out in two slaughterhouses in Pará. The nematodes were found on the white and serous viscera of the small intestine, being cleaned and discussed for analysis by light microscopy and scanning electron microscopy. The morphological and morphometric characteristics are compatible with S. labiatopapillosa parasitizing both species, with a prevalence of 25% (B. bubalis) and 24% (B. taurus). Information obtained by scanning electron microscopy was added to the description of the species, in addition to expanding the distribution of this parasite in the national territory.

Additional characterization of the adult worm Mammomonogamus laryngeus (Railliet, 1899) and the tissue lesions caused by the infection in buffaloes.

Mammomonogamus spp. are parasites with curious characteristics, such as the "Y" shape that results from male and female maintaining the permanent copulation position and the controversial presence or absence of spicules. These nematodes are hematophagous and cause damage to the upper respiratory tracts of cattle, sheep, goats, deer, wild yaks, and orangutans. Human infection is rare and most cases until now have been in the Caribbean Islands or in Brazil, and mainly in farmworkers but recently there have been reports affecting tourists. In the present work, the parasites were recovered from the laryngopharynx and larynx region of Bubalus bubalis on the island of Marajó, Pará, Brazil. Different microscopy methodologies were applied (bright field, fluorescence, and scanning electron microscopy) to explore the ultrastructural details of the anterior end, genital structures and the host tissue damage caused by the nematodes. The well-developed mouth is an important structure in the identification of these nematodes and used by the parasite to adhere to the host's tissue. Different methodologies in microscopy and molecular biology contributed to a detailed morphological description and showed the phenotypic position of Mammomonogamus laryngeus. Light and scanning electron microscopy (SEM) showed details of the papillae, amphids, festoons, ribs, and teeth. Fluorescence microscopy enabled a detailed characterization of different structures, such as the bursal rays and SEM enabled the visualization of the specialized features of the cuticle surface in the male and female. Histopathological analyses, cryofracture and environmental SEM experiments of the infected tissues were carried out in order to investigate the lesions resultant from the parasitism. In addition, the parasite couples were submitted to cryofracture and these results revealed details of the reproductive structures of both sexes, including the male spicule.

Nematode capilaridae in the tongue of Cerdocyon thous of free life in Brazil / Nematoide capilaridae na língua de Cerdocyon thous de vida livre no Brasil

Abstract Studies of helminths in road-killed wild animals are still uncommon but may provide promising results since they can identify the parasites in juvenile and adult hosts and meet the recommendations of current discussions on bioethics that prioritize alternative methods for the use of animals. This study evaluated three Cerdocyon thous individuals that were donated after dying from being run over. Two of them had small nematode adults in the epithelial and connective tissues of the tongue. The diagnosis was based on the presence of eggs, observed in histological sections, and morphological characteristics of the nematodes in the tongue. Morphologically, this nematode has a body with transverse grooves, simple mouth opening and no lips, esophagus and stichosome with stichocytes and bacillary bands along the body, which is characteristic morphology of the family Capilariidae and genus Capillaria . The presence of this nematode in the tongue of C. thous is an extremely important fact that contributes to what is known about the biodiversity of zoonotic parasites in wild canid populations. However, an explanation for these findings remains unclear because, until now, this has not been observed in the biological cycle of the species.

Resumo O estudo de helmintos de animais selvagens vitimados por atropelamento, ainda é uma prática pouco comum, porém pode ser promissor, uma vez que permite a identificação de helmintos a partir de hospedeiros juvenis e adultos, e atendem às atuais discussões em bioética, as quais priorizam métodos alternativos para o uso de animais. Foram avaliados 3 exemplares de Cerdocyon thous provenientes de doação pós-óbito por atropelamento. Dois deles apresentaram pequenos nematoides adultos inseridos nos tecidos epitelial e conjuntivo da língua. O diagnóstico foi baseado na análise de cortes histológicos que evidenciaram a presença de ovos no interior do nematoide e nas características morfológicas gerais do mesmo. Morfologicamente estes nematoides apresentavam corpo com estrias transversais, abertura bucal simples e lábios ausentes, esôfago trichuroiude com a presença de esticócitos e bandas bacilares ao longo do corpo, característica morfologicamente sugestiva da família Capillariidae e do gênero Capillaria . A presença de nematoides inseridos na língua de C. thous é um fato de extrema importância para o conhecimento da biodiversidade de parasitos zoonóticos circulantes presentes em populações selvagens de canídeos. Porém, permanece obscura a explicação para tais achados, uma vez que tal evento não foi observado no ciclo biológico das espécies até o momento.

Nematode capilaridae in the tongue of Cerdocyon thous of free life in Brazil.

Studies of helminths in road-killed wild animals are still uncommon but may provide promising results since they can identify the parasites in juvenile and adult hosts and meet the recommendations of current discussions on bioethics that prioritize alternative methods for the use of animals. This study evaluated three Cerdocyon thous individuals that were donated after dying from being run over. Two of them had small nematode adults in the epithelial and connective tissues of the tongue. The diagnosis was based on the presence of eggs, observed in histological sections, and morphological characteristics of the nematodes in the tongue. Morphologically, this nematode has a body with transverse grooves, simple mouth opening and no lips, esophagus and stichosome with stichocytes and bacillary bands along the body, which is characteristic morphology of the family Capilariidae and genus Capillaria . The presence of this nematode in the tongue of C. thous is an extremely important fact that contributes to what is known about the biodiversity of zoonotic parasites in wild canid populations. However, an explanation for these findings remains unclear because, until now, this has not been observed in the biological cycle of the species.

Mammary gland morphology in the northern Amazon red squirrel (Sciurus igniventris) / Morfologia da glândula mamária em esquilo do Norte Amazônico (Sciurus igniventris)

Sciurus igniventris is a squirrel with broad distribution in South America. We examined one female adult specimen which was donated after death by trampling. The aim of this work was describe the morphological characteristics of mammary gland of one specimen. The body was fixed using 10% aqueous formaldehyde. Tissues were processed and slides prepared following standard histological protocols. Morphological analysis of the mammary glands revealed similarities to those described in the literature for domestic and wild mammals. As special features in kind, macroscopically identified a pair of thoracic glands, followed by three pairs of abdominal glands. Microscopically the abundant presence of connective tissue dividing the alveolar-tubular glands. Similar to that described for domestic and wild mammals.

Sciurus igniventris é um esquilo com distribuição na América do Sul. Nós examinamos uma fêmea adulta que foi doada após morte por atropelamento. O objetivo do trabalho foi descrever as características morfológicas da glândula mamária de um exemplar da espécie. O animal foi fixado utilizando solução aquosa de formoldeído a 10%. Os tecidos foram processados e lâminas foram preparadas seguindo protocolos histológicos padrões. A análise morfológica da glândula mamária revelou similaridades com o que temos descrito na literatura para animais domésticos e selvagens. Como particularidades na espécie, macroscopicamente foi identificado um par de glândulas torácicas, seguidas por três pares de glândulas abdominais. Microscopicamente ocorreu a presença abundante de tecido conectivo dividindo as glândulas túbuloalveolares. Semelhante ao descrito para mamíferos domésticos e selvagens.

Histopathologic aspects in Plagioscion squamosissimus (HECKEL, 1940) induced by Neoechinorhynchus veropesoi, metacestodes and anisakidae juveniles.

Plagioscion squamosissimus (Heckel 1840), a fish endemic to the Amazon Basin and commonly known as the "silver croaker", plays an important role in the ecology and economy of Pará State, Brazil. Knowledge of host-parasite relationships is important to understanding the role of parasites in the control of natural host populations. This work describes histopathological aspects caused by several common intestinal parasites found during a helminthological survey of fish in northern Brazil. We observed a high prevalence of helminth infection, especially by J3 nematode juveniles of the family Anisakidae and metacestodes of the family Protocephalidae (both with 100% prevalence). An external capsule surrounded each juvenile with numerous juveniles inside sac-like structures formed of connective tissue. Inflammation was observed to be caused by infection of metacestodes, reaching the intestinal muscularis mucosa. Neoechinorhynchus veropesoi (38% prevalence) was found in the small intestine of P. squamosissimus, invading the mucosa, submucosa, and internal muscularis of the intestine causing intense inflammation. Histopathology of host-parasite relationships in fish has been rare, and the pathology of parasites in P. squamosissimus is described herein.

Histopathologic aspects in Plagioscion squamosissimus (HECKEL, 1940) induced by Neoechinorhynchus veropesoi, metacestodes and anisakidae juveniles / Aspectos histopatólogicos em Plagioscion squamosissimus induzidos por Neoechinorhynchus veropesoi, metacestódeos e juvenis da Família Anisakidae

Plagioscion squamosissimus (Heckel 1840), a fish endemic to the Amazon Basin and commonly known as the “silver croaker”, plays an important role in the ecology and economy of Pará State, Brazil. Knowledge of host-parasite relationships is important to understanding the role of parasites in the control of natural host populations. This work describes histopathological aspects caused by several common intestinal parasites found during a helminthological survey of fish in northern Brazil. We observed a high prevalence of helminth infection, especially by J3 nematode juveniles of the family Anisakidae and metacestodes of the family Protocephalidae (both with 100% prevalence). An external capsule surrounded each juvenile with numerous juveniles inside sac-like structures formed of connective tissue. Inflammation was observed to be caused by infection of metacestodes, reaching the intestinal muscularis mucosa. Neoechinorhynchus veropesoi (38% prevalence) was found in the small intestine of P. squamosissimus, invading the mucosa, submucosa, and internal muscularis of the intestine causing intense inflammation. Histopathology of host-parasite relationships in fish has been rare, and the pathology of parasites in P. squamosissimus is described herein.

Plagioscion squamosissimus (Heckel, 1840) é uma espécie de peixe endêmico da Bacia Amazônica e comumente conhecido como “pescada branca” e é de extrema importância ambiental e comercial no Estado do Pará. O estudo das relações parasito-hospedeiro são importantes para a compreensão do papel dos parasitas no ambiente. O presente trabalho descreve aspectos histopatológicos causados por helmintos intestinais e cavitários encontrados parasitando P. squamosissimus de Belém, PA. As larvas da família Anisakidade e metacestóides (Proteocephalidae) (ambos prevalência de 100%) encontravam-se recobertas por uma cápsula de tecido conjuntivo do hospedeiro, sendo observada fraca reação inflamatória para larvas de Anisakidae, no entanto observou-se que metacestoides embebidos na muscular interna apresentaram um infiltrado inflamatório. Neoechinorhynchus veropesoi (prevalência de 38%) encontrava-se embebido na camada muscular interna do intestino, induzindo reação inflamatória mais intensa. Estudos evidenciando as reações histopatológicas em peixes são raros, no entanto são de extrema importância para a compreensão das relações parasito-hospedeiro.