Gross morphological, histological and scanning electron specifications of the oropharyngeal cavity of the hooded crow (Corvus cornix pallescens)

Abstract

The present study was carried out on the oropharyngeal cavity of the hooded crow to investigate the gross and microscopic structures via gross anatomy, light microscopy and scanning electron microscopy (SEM). The gross anatomy clarified the elongated triangular shape of the oropharyngeal cavity with a non‐protruding tongue with a bifid apex. The lingual body contained median groove rostrally and separated caudally from the root by a transverse papillary crest. The laryngeal mound located posterior to the lingual root, contained midline laryngeal cleft and bounded caudally by a transverse row of pharyngeal papillae. The palate contained choanal cleft rostrally and infundibular slit caudally in addition to five palatine ridges. By light microscopy, the dorsal lingual epithelium was highly keratinised stratified squamous with a lingual nail in the most rostral part of the apex. Then, the thickness of the keratin layer decreased caudally, while in the ventral surface, the lining epithelium became non‐keratinised. The entoglossum supported the lingual body and root, but not extended to the apex. The lining epithelium of the palate was also keratinised stratified squamous and became none‐keratinised at the oral side of the choanal cleft. There were numerous lobules of polystomatic salivary glands in the lingual root and the palate. SEM revealed the arrangement of different types of papillae covering both the floor and the roof of the oropharynx besides numerous openings of salivary glands in the lingual root, laryngeal mound and the palate. These findings reflect the functional relationship of the oropharyngeal cavity of the hooded crow during feeding.

Posthatching developmental studies on the tongue and laryngeal entrance of the common quail (Coturnix coturnix, Linnaeus, 1758) in different five age‐stages

“…The tongue divided into three regions; apex, body, and root, identical to what was described in formerly published data (Abumandour, 2014a;Abumandour, 2018 Harmonious with these gross oversights, SEM imagery display that the round apex observed in all studied five developmental agestages, analogous to that noted in the goose, duck, quail and Egyptian laughing dove (Abumandour, Bassuoni, & Hanafy, 2019;Jackowiak et al, 2011;Parchami et al, 2010). The formerly published data described the presence of numerous appearance of the apex which were thought that it is correlated with the feeding style of the different feeding avian species such as; the oval apex in Hume's tawny owl (Abumandour & El-Bakary, 2017b), the pointed apex in the chicken, zebra finch and hoopoe Iwasaki & Kobayashi, 1986), the blunt apex (El-Mansi et al, 2020), the bifurcated apex note in the owl, Eurasian Hobby, house sparrow, and seagull (Abumandour, 2014a;Abumandour, 2018;Abumandour & El-Bakary, 2017b;Gewaily & Abumandour, 2020;Onuk et al, 2013).…”

“…while, they completely disappeared from the rudimentary tongue (Jackowiak et al, 2006;. These mucoid secretions are supposed to lubricate the oropharyngeal cavity and the esophagus to facilitate passage of the foods particles (El-Mansi et al, 2020;Gewaily & Abumandour, 2020).…”

“…Formerly, the avian tongue had more attentions from all researchers by different anatomical technique either; grossly, histologically, and scanning electron microscopy (SEM; Abumandour & El‐Bakary, 2019a; Al‐Ahmady Al‐Zahaby, 2016; Jackowiak, Andrzejewski, & Godynicki, 2006; Onuk, Tutuncue, Kabak, & Alan, 2013). Over time, researchers have tended to study the oropharyngeal cavity and its adaptation to the nature of the available food particles (Abumandour, 2018; Abumandour & Gewaily, 2019; El‐Mansi, Al‐Kahtani, Abumandour, Ezzat, & El‐Badry, 2020; Gewaily & Abumandour, 2020).…”

“…Al-Ahmady Al-Zahaby, 2016;Jackowiak, Andrzejewski, & Godynicki, 2006;Onuk, Tutuncue, Kabak, & Alan, 2013). Over time, researchers have tended to study the oropharyngeal cavity and its adaptation to the nature of the available food particles (Abumandour, 2018;Abumandour & Gewaily, 2019;El-Mansi, Al-Kahtani, Abumandour, Ezzat, & El-Badry, 2020;Gewaily & Abumandour, 2020).…”

Role of Fucoidan on the Growth Behavior and Blood Metabolites and Toxic Effects of Atrazine in Nile Tilapia Oreochromis niloticus (Linnaeus, 1758)

“…The histological examination was adopted according to Gewaily and Abumandour [ 35 ]. The dissected intestine samples were cut into pieces of approximately 0.5 cm 3 and fixed in neutral buffered formaldehyde 10% solution for 24 h. The samples were then dehydrated in ascending grades of alcohol, cleared with xylene, and embedded in paraffin wax.…”