Etude Morpho-Structurale des Papilles Linguales chez le Buffle (Bubalus bubalis)

Morphostructural characteristics of lingual papillae in buffalos The morphostructural characteristics of lingual papillae in 30 adult buffalos were studied by SEM. In this species, dorsal lingual surface papillae shos different shape so that their classification is complicated. Topography and morphology of conical and vallate papillae presents significant aspects. Particularly, the conical papillae have a different morphological organization when they are localized over the side of the tongue apex or over dorso-lateral tract of the tongue body. The functional aspects are discussed.     

Histomorphological features of the tongue of the Eurasian teal (Anas crecca)

This study presents the histomorphological features of tongue in Eurasian teal (Anas crecca); the smallest extant dabbling duck. Heads of four adult males and four adult females were used in this study. The results illustrate a tongue with three different parts; the apex with a lingual nail in ventral surface, the body with a lingual prominence in caudal part and some large and small conical papillae in lateral sides and the root, that was covered with many conical papillae in different sizes. Histological results revealed two types of keratinized and non‐keratinized epithelium covering parts of the tongue. The lingual salivary glands were observed in the lamina propria of the body and root of the tongue showed strongly periodic acid–Schiff (PAS)‐positive reaction. The yellow adipose tissue was located under the lamina propria on the body and root of the tongue. The filiform papillae between the conical papillae of the body were arranged densely. The sensory organs, which contain sensory receptors (Grandry and Herbst corpuscles), were located in the lamina propria of the body of the tongue. In conclusion, the anatomical and histological structure of the Eurasian teal’ tongue was generally similar to its family members such as domestic goose and duck but showed some differences that may be adoptions to the bird's habitat and mode of feeding.     

Investigations on the light and scanning electron microscopic structure of the lingual papillae in the angora goat (Capra hircus): II. Mechanical papillae

This study was conducted to examine the light microscopy (LM) and scanning electron microscopic (SEM) structures of mechanical papillae on the tongue in the Angora goat (Capra hircus). As study materials, the tongues of four adult female Angora goats were used. The samples were collected from the dorsal surfaces of the apex, body, root and torus of the tongue and the ventral surfaces of the lingual apex for light and scanning electron microscopic examinations. Three types of mechanical papillae were seen in Angora goat tongue: papilla filiformes, papilla lentiformes and papilla conicae.The filiform papillae were detected in the dorsal surface of the tongue from lingual apex to lingual torus, and in the ventro-lateral of the lingual apex and on both sides of the lingual torus. The morphological differences were observed in filiform papillae according to their location in the tongue. The lenticular papillae settled on the centre of the lingual torus. Two types of these papillae, irregular-round and pyramid-shaped were identified. The conical papillae were scattered all over the lingual torus, except for the central part and were also seen on the root of the tongue. In the light microscopic examination, it was found that mechanical papillae had a stratified squamous epithelium and a varying degree of keratin layer on epithelial surfaces. In this study, by examining the light and scanning electron microscopic structure of the mechanical papillae in the Angora goat tongue, their similarities and differences with other domestic and wild ruminant species were determined.     

Scanning electron microscopy study of the lingual papillae in the European mole (Talpa europea, L., Talpidae)

The tongue in the adult European mole (Talpa europea L.) was examined by scanning electron microscope. The elongated tongue with a rounded apex is about 12-13 mm in length and 3-4 mm in width. On the apex the shallow median groove is present. On the dorsal surface of the lingual mucosa two types of mechanical papillae and two types of gustatory papillae were observed. Mechanical papillae are represented by numerous filiform papillae with a single process, covering the whole surface of the apex and body of the tongue, and massive conical papillae, found on the root of the tongue. The structure and density of filiform papillae varies in the anterior and posterior part of the tongue. A unique trait of the tongue in the European mole is the occurrence on the apex of the tongue of a single row of conical papillae. Gustatory papillae are represented by numerous fungiform papillae and one pair of vallate papillae. Dome-shaped fungiform papillae in the anterior part of the tongue are arranged linearly along both margins of the tongue, whereas in the posterior part of the body of the tongue flat fungiform papillae are distributed evenly among filiform papillae. Oval vallate papillae are surrounded by a continuous furrow and a single pad. In the posterior part of the root behind conical papillae the surface of the mucosa is flat with numerous orifices of lingual papillae located there. Observations on the distribution and structure of gustatory papillae in the common mole did not show the existence of special traits, differing them from those in terrestrial insectivores. The comparison of the morphology of the tongue, the distribution and structure of the lingual papillae in the European mole with those in the other species of Insectivores, indicated of a general similarity of features within the family Talpidae.     

Scanning Electron Microscopic Study of the Lingual Papillae in the Arctic Fox (Alopex lagopus L., 1758)

This study aims to show the distribution and the three-dimensional structure of the lingual papillae in the arctic fox. The macro- and microscopic structure of the tongue and its lingual papillae was studied in 11 adult arctic foxes. Two types of mechanical papillae were distinguished on the dorsal surface of the tongue – filiform papillae and conical papillae. The gustatory papillae in the arctic fox are represented by fungiform, vallate and foliate papillae. The keratinized filiform papillae on the anterior part of tongue are composed of one big posterior process accompanied by 10–12 secondary anterior processes. The number of anterior processes of filiform papillae undergo a complete reduction within the area between the posterior part of the body of the tongue and area of the vallate papillae. The conical papillae cover the whole dorsal surface of the root of the tongue, including the lateral parts surrounding the area of the vallate papillae and the posterior part of the root. The size of the conical papillae increases towards the root of the tongue but their density decreases. In the arctic fox, there are three pairs of vallate papillae distributed on the plan of a triangle. The diameter of vallate papillae in each successive pair is bigger. The wall surrounding the body of the vallate papilla and its gustatory trench is composed of six to eight conical papillae joined at various degree. The foliate papillae on both margins of the tongue consist of seven to nine laminae.     

Morphological features of the Egyptian Ossimi sheep tongue: New scanning electron microscopic insights into its papillary system adaptations to Egyptian ecological conditions

The current study aims to illustrate the gross and scanning electron microscopic characterizations and ultrastructural adaptation of the lingual papillary system of Egyptian Ossimi sheep to Egyptian ecological conditions. The tongue had three regions: the apex (with a slightly bifurcated tip), the body (subdivided into rostral and caudal parts) and the root (subdivided into rostral papillary and caudal non-papillary parts). Torus linguae had two parts: the triangular rostral part (the caudal part of the body) and the quadrilateral wide part (the rostral part of the root). The lingual papillary system had mechanical (filiform, conical and lentiform) and gustatory (fungiform and circumvallate) types. Filiform papillae were heavily scattered on the dorsal surface of the apex, the rostral part of the body and the ventral surface of the papillary region of the tip. Filiform papillae had five subtypes (ventral and dorsal processed, triangular, leaf-like and triangular-processed papillae), while the conical papillae had three subtypes: two lingual (small, large) and one paralingual (elongated pointed), and the fungiform had two subtypes: the high-density ovoid (on the ventral surface of the tip) and round papillae (on the dorsal surface) that possessed a high number of taste pores, not previously described. They ranged from 5 to 10 for ovoid and 25 to 25 for round papillae. Each circumvallate papilla had an ovoid bulb (with 2–5 taste pores) encircled by an annular groove and two pads (i.e. not described previously). The papillary system's regional divergence was specialized for their harsh and semi-harsh diet.     

Morphological study of the lingual papillae in the barking deer, Muntiacus muntjak

The morphology of the tongue of the adult barking deer, Muntiacus muntjak, was examined by light and scanning electron microscopy. The result showed that the tongue of the barking deer was elongated with a rounded apex. Four types of lingual papillae were observed: filiform, fungiform, vallate and large conical papillae. The filiform papillae represented the most numerous types of lingual papillae. The fungiform papillae were distributed among the filiform papillae on the rostral and the body portions of the tongue. Ten to thirteen vallate papillae were distributed on both sides of the lingual prominence among the large conical papillae. Histologically, both the fungiform and vallate papillae contain taste buds in the epithelial layer. The distribution and types of lingual papillae found in the barking deer are similar to those in the other species that belong to the family Cervidae.     

Morphological and scanning electron microscopic studies of the tongue of the Egyptian fruit bat (Rousettus aegyptiacus) and their lingual adaptation for its feeding habits

This study was carried out on the tongues of 12 adult normal healthy Egyptian fruit bats of both sexes. The tongue is protrusible, elongated flat with a rounded apex and its wide and thickness increase gradually toward the lingual root. There are four types of lingual papillae; two mechanical and two gustatory. The tongue divided into three parts (anterior, middle and posterior), each part subdivides into three regions; two lateral regions and median region, in addition to the lingual apex to the anterior region. The lingual papillae close to the median region of the tongue were posteriorly directed toward the pharynx, while theses present on the lateral regions of the tongue are directed medioposteriorly. There are sex subtypes of the filiform papillae; three on the anterior part (small, conical and giant), two on the middle part (cornflower and leaf-like papillae) while the posterior part contain rosette shape filiform papillae, in addition to transitional papillae and conical papillae. Two gustatory papillae represented by; small number of fungiform papillae which scattered among the filiform papillae on lingual apex and two lateral regions of the anterior and middle part of tongue, while the three circumvallate papillae on the posterior part were arranged in a triangle form.     

Morphology of the tongue and laryngeal entrance in the Common pheasant (Phasianus colchicus); a light and scanning electron microscopic study

The present work was carried out to describe morphological features of the tongue and laryngeal entrance of the Common pheasantPhasianus colchicus, using light and scanning electron microscopy. The lingual apex was taper-shaped with a shallow median sulcus. A V-shaped papillary crest with 15–20 caudally directed conical papillae was located between the radix and corpus linguae. The second row of papillae consisting of three caudolaterally directed conical papillae was arranged caudal to the main papillary crest. The mons laryngealis was equipped caudally with a double-layer of large conical papillae as pharyngeal crest, and few small conical papillae were seen around the glottis. Scanning electron microscope (SEM) observation showed that the apex linguae and corpus were covered with compact filiform papillae, while the radix linguae were free of papillae. Numerous openings of salivary gland can be seen on the radix linguae and mons laryngealis at higher magnification. On histological sections, all parts of the tongue and mons laryngealis were covered with a keratinised stratified squamous epithelium. The keratinised layer became thinner rostro-caudally. The simple alveolar salivary glands were distributed in the submucosa from the apex linguae to the radix linguae as well as the mons laryngealis. PAS staining revealed mucin-secreting activity of this glands. According to the findings, although the tongue and laryngeal entrance of the Common pheasant is characteristics of a galliform bird, it has some features similar to passeriformes and falconiformes.     

Scanning Electron Microscopic Study of the Tongue in the Owl (Strix uralensis)

The dorsal lingual surfaces of adult owl (Strix uralensis) were examined by scanning electron microscopy. The length of the tongue was about 2 cm. The tip of the tongue of the owl was bifid. Three parts were distinguished in the tongue of the owl: the apex, the body and the root of the tongue. The conical region between the lingual apex and lingual root was a very wide area. There were thread‐shaped processes/cells of epithelium in the lingual apex. The small or large conical papillae were observed on the lingual body. The many openings of the lingual glands existed in the lingual body and lingual root.     

Morphological Studies of the Tongue of the Egyptian Water Buffalo (Bubalus bubalis) and Their Lingual Papillae Adaptation for Its Feeding Habits

This work was conducted to describe the morphological characters of the tongue of Egyptian water buffalo (Bubalus bubalis). The lingual root and the dorsal middle region of apex and body in addition to the dorsal and ventral surface of lingual tip were devoided from any fungiform papillae. The lingual tip contains conical papillae only. The ventral surface of lingual apex was divided into two portions by the U‐shaped fungiform line into papillary and non‐papillary region. Histological investigation on the lingual surface epithelium and lamina propria submucosa reflects differences in these layers in different parts of the tongue. By SEM, there are two subtypes of filiform papillae: caudally directed papillae on dorsal surface and rostrally directed papillae on the lateral region of ventral surface of lingual apex. There are two subtypes of conical papillae: small slightly rostrally directed papillae on dorsal and ventral surface of lingual tip and large posteromedially directed papillae on dorsal surface of lingual root. The rounded circumvallate papillae consisted of round bulb surrounded by deep circular groove, which surrounded by circular pad. Higher magnification of filiform papillae indicates the presence of microcrests separated by microgrooves, and these microgrooves consisted of microrodes. The fungiform surface having micropores on the tip of elevated tubercle for taste buds pores. All these observed structures (microcrests, microgrooves, microrodes, tubercles, microridges) in a higher magnification allow animals to transport food particles through the oral cavity and help in the defensive behaviour. There are strong correlations between the tongue anatomical characteristics and its functions.     

Anatomical and surface ultrastructural investigation of the tongue in the straw-coloured fruit bat (Eidolon helvum,Kerr 1972)

The morphology of tongue in straw-coloured fruit bat from tropical forests was evaluated in relation to frugivorous diets and in comparison with other species that consumes other food types. Gross, stereomicroscopy, scanning electron microscope and histological methods were used. The tongue was relatively long with round tip, which closely fitted into oral cavity. Five types of mechanical papillae included crown-like and trifid filiform papillae. Also bulky, cone-shaped papillae and long conical papillae were identified. These mechanical types also showed variations in shape, size and number of processes of papillae. Transitional forms of these mechanical papillae were present. Fungiform papillae with taste pores were interposed amongst filiform types in apex and body; three ovoid-shaped vallate papillae were in triangular arrangement on root and displayed taste pores. Some bulky, cone-shaped papillae surrounded the vallate papillae. Histologically, mechanical filiform types showed highly keratinized stratified squamous epithelium and dense connective tissue core with secondary papillae. Taste buds appeared in fungiform and vallate papillae. Neutral and acidic secretions were identified in lingual glands of root. The presence of prominent filamentous processes of filiform papillae and conical papillae of the tongue in conjunction with gustatory papillae ensures adaptation to copious fruit diets. The gross morphometric and histometric parameters of the tongue did not differ remarkably from previous values obtained for some fruit bats with comparable weight. This investigation showed similarities with fruit bats such as large flying fox and Egyptian fruit bat and reflect common diet and feeding habits but varied from insectivorous and nectivorous bats.     

Anatomical and histological structure of the tongue and histochemical characteristics of the lingual salivary glands in the Chukar partridge (Alectoris chukar,Gray 1830)

1. The aim of the study was to examine the morphology of the tongue and the histochemical features of the lingual salivary glands in this species.

2. The tongue was elongated, terminating in a rather sharp, dagger-like apex. On the surface of the tongue and situated between the body and root of the tongue, two rows of conical papillae, the sharp apices of which pointed towards the posterior part of the tongue, were observed. The keratinised epithelium lining the dorsal surface lacked typical gustatory papillae. However, it was observed that taste buds were present in the epithelium of the lingual body and root. The tongue was supported by a structure composed of hyaline cartilage, the paraglossum, which extended from the lingual root to the apex. Simple branched tubular glands, which were encapsulated by connective tissue, were embedded within the submucosa in the body (anterior salivary glands) and root (posterior salivary glands) of the tongue. It was observed that the secretion of the lingual glands contained neutral mucins, proteoglycans containing carboxylic acid, weak and strong sulphated groups, N-acetylated sialomucins, but lacked glycogen.

3. It was demonstrated that, the general morphological features, papillary distribution of the tongue and the histological structure of the mucosa epithelium and the supportive elements displayed similarity to those of other domestic avian species. It was also determined that, in view of the particular feeding types, in the partridge, the presence of the papillary crest was not correlated with diet.     

Anatomical and histological aspects of the bovine lingual tonsil

The localization of the bovine lingual tonsil is described as a prerequisite for the removal of specified risk material from the tongue meat in order to restrict the risk arising from bovine spongiform encephalopathy (BSE) to public health. The major part of this tonsil can be located macroscopically by the openings of its follicular crypts at the root of tongue. This part consists of organized aggregations of lymph nodules. Additional solitary primary lymph nodules and diffuse accumulations of lymphocytes are macroscopically invisible but are bilaterally present in the area extending 2 cm caudal to 3 cm rostral to the last vallate papillae. By sectioning the tongue 3 cm rostral to the last vallate papillae, undermining the lingual mucosa to the level of these papillae and making a transverse cut towards the lingual process of the basihyoid bone, the greater part of the lingual tonsil can efficiently be removed. Finally, immunohistochemical staining demonstrated the presence of T and B lymphocytes, suggesting that the bovine lingual tonsil can be considered as a site where an immune response can be induced.     

Scanning electron microscopic and histological features of the oral cavity of the Egyptian tortoise (Testudo kleinmanni)

This investigation was led to depict the structural and functional adaptations of the oral cavity of herbivorous Egyptian tortoises using scanning electron and light microscopes. The SEM showed that the triangular papillary tongue possessed three conical papillary subtypes: the rectangular conical on the tip, the round conical on the rest of the dorsal lingual surface and the elongated conical on the caudal portion of the lingual wing. The presence of the serrated lips with their valves compensated for the absence of the teeth. The rostral part had a vomeronasal opening while the middle part had the choana, but the caudal part had numerous openings of the salivary glands. There are three palatine folds: a single median palatine fold, two peripheral palatine folds and the choanal fold. The current histological results show the keratinized dorsal lingual surface, in which the keratinized layer extended to cover the papillae. Two types of lingual glands, according to their position, are papillary superficial and deep lingual glands. Papillary or superficial glands open in the interpapillary spaces via narrow openings, while the deep glands are surrounded by well-developed muscles and open via wide openings on the dorsal lingual surface. An entoglossal cartilaginous structure of hyaline cartilage was found in the mid- and hindtongue, with numerous chondrocytes lodged within the lacunae. Our results conclude that the oral cavity of the herbivorous Egyptian tortoise was adapted to the dietary and vigorous demands of the Egyptian fauna.