Morfologia comparada do aparelho respiratório de capivaras (Hydrochoerus hydrochoeris)

Nascente

et al. 2023

Anat Histol Embryol

Giant anteater (Myrmecophaga tridactyla) is an endangered species that resides in much of Latin America, but it has been losing its habitat, especially in the Cerrado biome, where it constantly suffers traumas resulting from fires and roadkill. The anatomical knowledge of structures of the respiratory system is important for a better morphophysiological understanding of the species. Thus, this study aimed to perform the macroscopic and histomorphological description of the pharynx and larynx of the giant anteater. Twelve adult giant anteaters were used, three of them fixed in buffered formalin for further dissection and pharynx and larynx macroscopic analysis of structures. From the other animals, samples of the pharynx and larynx were collected and prepared for histological evaluation under optical microscope. Macroscopically, their pharynx and soft palate are extensive, and the anatomical location of these structures and the larynx differs greatly from that described in other species. The larynx, although more caudal, was similar to that of other animals. Histologically, the epithelium of these regions varied between the pseudostratified ciliated columnar and the non‐keratinized stratified squamous epithelium. Laryngeal cartilages were composed of elastic (epiglotti) and hyaline cartilages (arytenoid, cricoid and thyroid cartilage), with an ossification process and glandular clusters around the hyaline cartilage. The distinct anatomical location of the pharynx and larynx of Myrmecophaga tridactyla is the main macroscopic finding of this study, besides the length of the pharynx and soft palate of these animals.

Section: Pharyngeal Musclessupporting

confidence: 88%

Macroscopic and histological aspects of the pharynx and larynx of the giant anteater (Myrmecophaga tridactylaLinnaeus, 1758)

Nascente

et al. 2023

Anat Histol Embryol

“…The right lung is formed by the cranial, middle, caudal and accessory lobes, and the left one by the cranial and caudal lobes. The same features are observed in dogs, cats, pigs (König & Liebich 2016), capybaras (Moreto et al 2017), coatis (Oliveira et al 2011), and giant anteaters. However, different from these animals, and similar to cattle, goats, and sheep, the cranial lobe of the right lung in Myrmecophaga tridactyla is divided into cranial and caudal parts, as described by Giraldi et al (2017).…”

Section: Discussionsupporting

confidence: 65%

“…The trachea is the longest of these tubes; it goes from the larynx's cricoid cartilage to the bifurcation in the thoracic cavity (König & Liebich 2016). However, the length of this organ in giant anteater representatives was shorter than in species such as ruminants and horses, which show from 48 to 60 tracheal cartilages; dogs, who have 42 to 46 cartilages; cats, who have 38 to 43 cartilages (König & Liebich 2016), capybaras have from 35 to 46 cartilages (Moreto et al 2017) and 34 cartilages in the coatis, on average (Oliveira et al 2011). On average, giant anteaters have 22 tracheal cartilages; this number was close to the one reported for skunks, which present 25 cartilages, on average (Bertassoli et al 2013).…”

Section: Discussionmentioning

confidence: 98%

Macroscopic and microscopic morphology of the trachea and lungs of giant anteater (Myrmecophaga tridactyla)

et al. 2020

Giant anteater (Myrmecophaga tridactyla) is a wild mammal distributed in Central and South America; nowadays, it is classified as an endangered species. Research about the macroscopic and histomorphological aspects of its respiratory tract is scarce, and, sometimes, it limits the treatment provided to sick animals and impairs species preservation. Thus, the present study aims to describe the macroscopic and microscopic morphology of its lower respiratory tract, including trachea and lungs. To do so, 12 adult giant anteaters from “Centro de Triagem de Animais Silvestres de Goiânia” (CETAS-GO), Goiás State, Brazil, were used in the research after natural death or euthanasia. Three of these animals were used for macroscopic assessments; they were fixed in 10% buffered formalin and dissected. Trachea and lung tissue samples were collected from nine animals right after death and fixed in 10% buffered formalin for histomorphological analysis; they were processed, embedded in paraffin, and inked with hematoxylin-eosin (HE), periodic acid-Schiff (PAS), and Masson’s trichrome. The macroscopic analysis showed that the trachea in this species is proportionally short and presents from 19 to 27 tracheal cartilages. The right lung presents four lobes and the left one, two. The microscopic analysis evidenced respiratory epithelium of the ciliated cylindrical pseudostratified type, without evident goblet cells in the mucosa layer of the trachea and bronchi. The pulmonary visceral pleura is thick, similar to other large domestic mammals - complete septa extend from the pulmonary visceral pleura. In conclusion, the macroscopy and histomorphology of giant anteater’s lower respiratory tract, represented by trachea and lungs, are similar to that of other domestic and wild mammals. Pulmonary histomorphology is mainly similar to that of pigs and ruminants: it has thick visceral pleura that emits complete septa of conjunctive tissue, which enable lobular parenchymal architecture.

“…This number is similar to the European Hamster which had 14 rings (Reznik, Reznik‐Shuller, & Mohr, ). However, They differ from other rodents like mole rats that showed 29 rings (Ilgun, Yoldas, Kuru, & Özkan, ) and the capybara who presented 43 tracheal rings (Moreto, Oliveira, Bertassoli, & Neto, ). Hare () describes that the tracheal rings of mammals vary from 29 to 60, differing of our results.…”

Section: Discussionmentioning

confidence: 61%

Morphology of theOligoryzomys nigripesrespiratory system

Mario

Borghesi

Hayashi

et al. 2018

Anat Histol Embryol

Rodents are important in the transmission of infectious diseases that affect the respiratory tract, including simple infections and those caused by specific pathogens. These animals are natural reservoirs of zoonoses that cause many public health diseases. Basic knowledge on the morphology of these animals is important as basic research is useful for applied studies, such as the development of clinical, therapeutic, surgical and clinical models. Morphological data of respiratory tract in Oligoryzomys nigripes are absent in the literature. Therefore, the aim of this study was to perform a morphological analysis of the respiratory tract of O. nigripes. Five adult females from the environmental reserve in São Joaquim da Barra, São Paulo were used, donated to the Museum of Veterinary Anatomy (FMVZ/USP). Several morphological features follow the same pattern seen in rodents; however, this species showed some differences such as the presence of three lobar bronchi, nonlobed left lung and the right lung constituted by two lobes. Respiratory epithelium lined the whole respiratory tract and was seen using scanning electron microscopy the oval shape of the parenchyma and alveoli.