Anatomical Study of the Diaphragm of the Opossum (Didelphis albiventris)

Abstract

The anatomical characteristics of the South American opossum diaphragm were described. Five male and seven female adult opossums, weighing between 700 and 1110 g, were used. Animals were killed by ether inhalation saturation. The abdominal and thoracic walls were dissected and opened, the viscerae were removed and the diaphragm anatomy was described and photographed in situ. After diaphragm removal, some dimensional data were taken and tabled. Primary branches of the phrenic nerves were dissected under a surgical microscope. The secondary branches were studied and described by transillumination after clarification in acetic acid. The opossum diaphragm is domed and has a mean area of 54.33 +/- 3.8 cm2. Well-identified costal, sternal and lumbar parts form the peripheral muscular region. The central tendinous region presents with a V-like form. Three folioles comprise the phrenic centre and present different dimensions. The caudal vena cava passes through its foramen between the ventral and right dorsal folioles. Both right and left phrenic nerves present one ventral branch and one dorsolateral trunk in 50.0% and 66.67% of the cases, respectively.

Comparative analysis of origin and branches of phrenic nerve in the diaphragm of the crab‐eating fox (Cerdocyon thous) and domestic dog (Canis lupus familiaris)

“…(1993) in marmosets and domestic cats (Moreira et al, 2007) and contrasting to what was described for guinea pigs (Carvalho et al, 1996), and opossums (Cassel et al, 2002), which the lumbar branch innervates the tendinous centre and the costal and sternal branches emit filaments to the caudal vena cava.…”

“…The origin of phrenic nerve in wild animals was reported in previous studies of brachial plexus of crab‐eating foxes (Souza Junior et al, 2014) and pampas fox (Souza Junior et al, 2017). But, the few descriptions about the distribution of the phrenic nerve in the diaphragm of wild animals are restricted to marmosets (Amorim Júnior et al, 1993), agoutis ( Dasyprocta agouti ) (Carvalho et al, 1996) and opossums ( Didelphis albiventris ) (Cassel et al, 2002).…”

Diaphragm morphology of Guinea pig (Cavia porcellus)

“…Concerning the tridimensional shape, the tendineous center of the "U"-shaped guinea pig diaphragm differs from the "V"-shaped tendineous center of the diaphragm of white tuffed-ear marmoset (Lessa et al, 2012a), white-fronted marmoset (Lessa et al, 2012b), white-ear opossum (Didelphis albiventris), and of albino rat (Cassel et al 2001), also differing from the "I"-shaped from the manatee (Rommel and Reynolds, 2000).…”

Descrição morfológica do diafragma do sagui-de-tufo-branco (Callithrix jacchus)

“…Sendo tal formato em "V" o encontrado para os espécimes analisados de Callithrix jacchus, ao contrário do observado para a espécie Cavia porcellus (porquinho-da--índia) que deteve um formato de similar a letra "U". mas sendo similar ao encontrado para as espécies Didelphis albiventris (gambá-orelhas-brancas) e para o rato albino (Cassel et al 2001).…”

“…Ainda para o gambá-de-orelhas-brancas este deteve uma área diafragmática média de 54,33± 3,8 cm 2 , valor este similar ao encontrado para os animais domésticos e de laboratório, indicando assim que o tamanho da área do diafragma é diretamente proporcional ao tamanho do animal analisado (Cassel et al 2001).…”