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The scanning electron microscopic study of lingual papillae in the silver fox (Vulpes vulpes fulva, Desmarest, 1820)
ANNALS
OF ANATOMY ELSEVIER
Ann Anat 186 (2004):179-183 http://www.elsevier-deutschland.de
The scanning electron microscopic study of lingual papillae in the silver fox (Vulpes vulpes fulva, Desmarest, 1820) Hanna Jackowiak and Szymon Godynicki Department of Animal Anatomy, Agricultural University of Poznan, ul. Wojska Polskiego 71 C, PL 60-625 Poznafi, Poland
Summary. The tongues of adult silver foxes were studied using scanning electron microscopy. Five types of lingual papillae were found on the dorsal surface of the tongue. The most numerous papillae were filiform papillae covering the apex and body of the tongue. The filiform papillae on the anterior part of the tongue are divided into 1 main and 10-12 accessory processes. In the posterior part of the body of the tongue the number of accessory processes is reduced. Fungiform papillae are located between the filiform papillae. A cluster of 12 large fungiform papillae was found on the apex of the tongue. Conical papillae are located in the area of the vallate papillae and cover the posterior part of the root of the tongue. Their size increases towards the pharynx, where they are distributed more sparsely. In the silver foxes there were two pairs of vallate papillae. The wall surrounding each papilla and its gustatory trench forms partly connected 6-8 conical papillae. The foliate papillae on both margins of the tongue body are small and consist of 4-5 laminae. The distribution and type of lingual papillae found in the silver fox are similar to those in the other species belonging to the family Canidae.
Key words: Lingual papillae - Silver fox - Scanning electron microscopy
Introduction The distribution and structure of mechanical and gustatory papillae on the dorsal surface of the tongue in mamCorrespondence to: H. Jackowiak E-mail: hannaj @owl.au.poznafi.pl
mals are varied and highly specific for individual systematic groups, as well as the species of the animals (Thome 1999; Iwasaki 2002). The SEM and T E M observations of the three-dimensional structure of lingual papillae conducted so far concerned mainly laboratory and domestic animals. In the carnivores, observations of the tongue structure have been conducted on the adult and newborn of the dog (Iwasaki and Sakata 1985; Kobayashi et al. 1987; Iwasaki and Miyata 1989) and in the cat (Boshell et al. 1982; Chamorro et al. 1987; Kobayashi et al. 1988; Iwasaki 1992). Morphological investigations of the tongue surface in wild animals are scarce and so far have been conducted e. g. on a newborn individual of the Asian black bear, and the panther, and an adult bush dog (Emura et al. 2000; Emura et al. 2001). The aim of the present study in SEM is to examine the location and morphology of lingual papillae on the dorsal surface of the tongue in the silver fox, which is a subspecies of the American fox (Vulpes vulpes fulva, Desmarest,
182o).
Material and methods This study was performed on a total of 8 tongues of adult silver foxes. Immediately after slaughtering, the tongues were dissected and washed in saline. Samples of the apex, body and root of the tongue were fixed in 2.5% glutaraldehyde in 0.1 M cacodylate buffer at 4 °C for 3 hours. After rinsing in the cold 0.1 M cacodylate buffer the samples were postfixed in 1% osmium tetroxide at 4 °C. After the dehydration of tissues in the alcohol and acetone series and critical point drying (CO2) the probes were mounted on aluminum stubs covered with carbon tabs and sputtered with a gold coat. Specimens were examined under a scanning electron microscope LEO 435 VP at 15 kV. 0940-96021041186102-I 79 $30.0010
Results The tongue in the silver fox is elongated with a rounded flat apex. It is approximately 7-8 cm in length. Macroscopically a distinct narrow median groove dividing the tongue into two symmetric parts may be seen on the dorsal surface of the apex and the body of the tongue. The groove disappears at the root of the tongue in front of the vallate papillae.
The apex and body of the tongue in the silver fox are covered by two types of lingual papillae, i.e. fungiform and filiform papillae. Approximately 12 fungiform papillae with a diameter of approx. 300 ~tm, were observed located close to one another, on the margin of the tongue apex (Fig. 1). The fungiform papillae on the surface of the apex and the body of the tongue are smaller, 150 gm in diameter (Fig. 2, 3). They are evenly distributed among filiform papillae and their density is 2-3/1 m m 2. The surface of fungiform papillae is slightly projected or flat. A total of 4-5 pores of the taste buds were observed on the surface of each papilla. Fungiform papillae were also sporadically observed on the root of the tongue, between conical papillae. Filiform papillae cover the apex and body of the tongue and the margins of the tongue (Fig. 1-3). The density of papillae ranges between 39 and 50/1 m m 2. In the structure of filiform papillae a basal part may be distinguished, approx. 130-150 pm in width, from which numerous processes branch off. The processes tilt towards the back of the tongue. Figures 2 and 3 present filiform papillae characteristic of the apex and body of the tongue. In the posterior part of the filiform papilla there is a bigger main process resembling a thorn, with a length of up to 250 gin, whereas 9-12 narrow accessory processes with a sharpened tip and a length of approx. 100 ~tm are observed on the anterior part of the papilla. The accessory processes of the filiform papillae become gradually reduced to 1 main and 2-3 smaller ones towards the root of the tongue (Fig. 4). Filiform papillae with a reduced number of accessory processes are also observed on the margin of the tongue apex (Fig. 1). In the posterior part of the body and on the root of the tongue, forming the pharyngeal wall, three types of lingual papillae may be distinguished, i.e. conical, vallate and foliate papillae. Conical papillae surround the area of the vallate papillae and cover the whole surface of the tongue root (Figs. 5, 6). These papillae are larger than filiform papillae. The width of conical papillae at the base reaches approx. 200 pm. The height of the papillae increases towards the pharynx, reaching ca. 750 pm. The
Fig. L Scanning electron micrograph of the apex of the tongue in the silver fox. On the margin of the apex, fungiform papillae (Fu) and filiform papillae with reduced processes (arrows) are visible. The dorsal surface of the lingual apex is covered by filiform papillae (Fi). x 225 Fig. 2. Scanning electron micrograph of the dorsal surface of the body of the tongue in the silver fox. Round fungiform papillae are scattered among filiform papillae with numerous accessory processes, x 68 Fig. 3. A higher magnification of the dorsal surface of the anterior part of the lingual body in the silver fox. The accessory processes (ap) and main process (mp) directed towards the back of the tongue arise from the base of the filiform papilla. Fu = fungiform papilla, x 238
180
In the anterior part of the tongue root in the silver fox there are 2 pairs of vallate papillae, 1.4-1.0 m m in diameter. The 2 pairs of vallate papillae are on oblique lines in a V form on the root of the tongue (Fig. 5). In some individuals the papillae of the anterior pair are slightly bigger. Each vallate papilla and its gustatory groove are surrounded by 6-7 conical papillae, partly fused at the base. The surface of the vallate papillae is smooth. In one individual, shallow grooves were observed on the surface of the anterior pair of vallate papillae. On the margins of the posterior part of the tongue body, next to the palatoglossal arch of the soft palate, small foliate papillae are found, formed from 4-5 laminae approx. 300-450 gm in width (Fig. 8). On the border between the margin and the dorsum of the tongue, the laminae fused with the bases of conical papillae.
density of conical papillae varies. Near vallate papillae it is approx. 20/1 m m 2, whereas in the posterior part of the root, conical papillae are more widely spaced and their density is only 5-6/1 m m 2. In the anterior part of the base, in conical papillae, single, round openings of lingual glands with the diameter of 10 ktm were observed on the root of the tongue (Fig. 6, 7).
Discussion Observations of the dorsal surface of the tongue in the silver fox under a scanning electron microscope made it possible to distinguish three types of gustatory papillae and two types of mechanical papillae. Mechanical papillae, among which filiform and conical papillae were found, are the most numerous on the tongue of the silver fox. Their function is connected with the transporting and swallowing of comminuted food to the pharynx. Filiform papillae are found on the dorsum of the apex and the body of the tongue, and gradually - as a result of the reduction of accessory processes on the tongue root, they are replaced by the more massive conical papillae covering the tongue as far as the pharynx. A similar distribution of filiform and conical papillae was reported in the dog and in the bush dog (Iwasaki and Sakata 1985; E m u r a et al. 2000). In the fox, similarly to the dog, filiform papillae, primarily in the anterior part of the tongue, undergo a characteristic division into processes, of which one - the posterior process - is dominant. Such a type of structure in filiform papillae is common in the Carnivora,
Fig. 4. A higher magnification of the posterior part of the lingual body in the silver fox. The filiform papillae are larger and their accessory processes (arrows) are reduced in the anterior part of each papillae. × 120 Fig. 5. Scanning electron micrograph of the anterior part of the root of the silver fox. The surface of the mucosa is covered by conical papillae (Co). Two vallate papillae (Va) are visible. The larger conical papillae surrounding the groove of the vallate papillae are partly fused, x 65 Fig. 6. Scanning electron micrograph of the conical papillae on the posterior part of the root of the tongue in the silver fox. Note the opening of the lingual glands on the anterior surface of the base of the conical papillae (arrows). × 310 181
as has been found not only within the Canidae family, but also in representatives of other families, i. e. in the family Felidae (Chamorro et al. 1987). It needs to be emphasized that filiform papillae with numerous, but identical processes, are observed in omnivorous animals, such as the pig, as well as some primates (Kobayashi et al. 1995, 1997). The distribution of gustatory papillae, i.e. fungiform, vallate and foliate papillae in the silver fox also closely resembles the arrangement of these lingual papillae in the dog (Iwasaki and Sakata 1985). The present observations showed a concentration of the fungiform papillae at the top of the tongue. These papillae are two times larger than those scattered on the body of the tongue and probably allow the animals to sample and taste food. The number and arrangement of the 4 vallate pa-
pillae, observed in the fox, are similar to those observed in the dog and the cat (Iwasaki and Sakata 1985; Chamorro et al. 1987). It should be pointed out that vallate papillae of the silver fox are also surrounded by partly fused conical papillae. As is the case in results from previous studies the number of vallate papillae in carnivorous animals varies. According to Emura et al. (2000) in the bush dog closely related to the dog, on each side of the tongue there are 5 vallate papillae, while each papilla is completely surrounded by a continuous pad. A larger number of vallate papillae was observed in other investigated carnivorous species. Thus, in the Asian black bear there are 7-8 papillae, whereas in the panther there are 10 papillae in all (Emura et al. 2000, 2001). The third type of gustatory papillae found in the fox are small foliate papillae. They exhibit a typical laminar structure previously found to be common in mammals (Chammoro et al. 1987; Kobayashi 1992). Taking into consideration the observations reported by Chammoro et al. (1987), who found digitiform foliate papillae in the cat, it may be supposed that morphological variability of these papillae is found in the carnivores. Summing up the results of our observations, it may be stated that in the silver fox the distribution and types of lingual papillae are similar to those in the other species of the Carnivora belonging to the family Canidae.
References
Fig. 7. A higher magnification of the opening of the lingual glands (arrow). On the cornified cells of the surface of the lingual epithelium (C) a delicate pattern of microridges were observed, x 2240 Fig. 8. Scanning electron micrograph of the foliate papilla (+-Fo--+) on the margin of the body of the tongue in the silver fox. The 5 laminae of the papilla are divided by an elongated grooves. In the dorsal part of the papilla the laminae fuse with the base of the conical papillae (Co). x 111
Boshell JL, Wilborn WH, Singh BB (1982) Filiform papillae of cat tongue. Acta Anat 114:97-105 Chamorro CA, Sandoval J, Fernandez JG, Fernandez y P de Paz G (1987) Estudio comparado de las Papillas linguales del Gato (Felis catus) y del Conjeo (Oryctolagus cuniculus ) mediante el Microscopio electronico de barrido. Anat Histol Embryol 16:37--47 Emura S, Tamada A, Hayakawa D, Chen H, Shoumura S (2000) Morphology of the dorsal lingual papillae in the bush dog (Speothos venaticus). Okajimas Folia Anat Jpn 77:137-141 Emura S, Hayakawa D, Chen H, Shoumura S (2001) Morphology of the dorsal lingual papillae in the newborn panther and asian black bear. Okajimas Folia Anat Jpn 78:173-178 Iwasaki S, Sakata K (1985) Scanning electron microscopy of the lingual dorsal surface of the beagle dog. Okajimas Folia Anat Jpn 62:1-14 Iwasaki S, Miyata K (1989) Fine structure of the filfform papilla of beagle dog. J Morphol 201:235-242 Iwasaki S (2002) Evolution of the structure and function of the vertebrate tongue. J Anat 201:1-13 Iwasaki S (1992) Fine structure of the dorsal lingual epithelium of the domestic, newborn kitten, Felis catus. Anat Anz 174: 293-300 Kobayashi K, Miyata K, Iino T (1987) Three-dimensional structures of the connective tissue papillae of the tongue in newborn dogs. Arch Histol Jpn 50:347-357 Kobayashi K, Miyata K, Iwasaki S, Takahashi K (1988) Three dimensional structure of the connective tissue papillae of cat lingual papillae. Jpn J Oral Biol 63:719-731
182
Kobayashi K (1992) Stereo architecture of the interface of the epithelial cell layer and connective tissue core of the foliate papillae in the rabbit tongue. Acta Anat 143:109-117 Kobayashi K, Kamakura M, Takahashi M (1995) Comparative observations on lingual papillae and their connective tissue cores in three primates. A scanning electron microscopic study. It J Anat Embryol 100:340-358 Kobayashi K, Kumakura M, Yoshimura K (1997) Stereo structural differences of lingual papillae and their connective tissue
cores in three kinds of artiodactyls. In: Recent Advances in Microscopy of Cells, Tissues and Organs. Motta PM (Ed), pp 357-361 Thome H (1999) Mundh6hle und Schlundkopf. In: Nickel R, Schummer A, Seiferle E. Lehrbuch der Anatomie der Hanstiere. Bd II, 8. Aufl., Parey Buchverlag: Berlin, pp 20-102
Accepted October 20, 2003
183
OF ANATOMY ELSEVIER
Ann Anat 186 (2004):179-183 http://www.elsevier-deutschland.de
The scanning electron microscopic study of lingual papillae in the silver fox (Vulpes vulpes fulva, Desmarest, 1820) Hanna Jackowiak and Szymon Godynicki Department of Animal Anatomy, Agricultural University of Poznan, ul. Wojska Polskiego 71 C, PL 60-625 Poznafi, Poland
Summary. The tongues of adult silver foxes were studied using scanning electron microscopy. Five types of lingual papillae were found on the dorsal surface of the tongue. The most numerous papillae were filiform papillae covering the apex and body of the tongue. The filiform papillae on the anterior part of the tongue are divided into 1 main and 10-12 accessory processes. In the posterior part of the body of the tongue the number of accessory processes is reduced. Fungiform papillae are located between the filiform papillae. A cluster of 12 large fungiform papillae was found on the apex of the tongue. Conical papillae are located in the area of the vallate papillae and cover the posterior part of the root of the tongue. Their size increases towards the pharynx, where they are distributed more sparsely. In the silver foxes there were two pairs of vallate papillae. The wall surrounding each papilla and its gustatory trench forms partly connected 6-8 conical papillae. The foliate papillae on both margins of the tongue body are small and consist of 4-5 laminae. The distribution and type of lingual papillae found in the silver fox are similar to those in the other species belonging to the family Canidae.
Key words: Lingual papillae - Silver fox - Scanning electron microscopy
Introduction The distribution and structure of mechanical and gustatory papillae on the dorsal surface of the tongue in mamCorrespondence to: H. Jackowiak E-mail: hannaj @owl.au.poznafi.pl
mals are varied and highly specific for individual systematic groups, as well as the species of the animals (Thome 1999; Iwasaki 2002). The SEM and T E M observations of the three-dimensional structure of lingual papillae conducted so far concerned mainly laboratory and domestic animals. In the carnivores, observations of the tongue structure have been conducted on the adult and newborn of the dog (Iwasaki and Sakata 1985; Kobayashi et al. 1987; Iwasaki and Miyata 1989) and in the cat (Boshell et al. 1982; Chamorro et al. 1987; Kobayashi et al. 1988; Iwasaki 1992). Morphological investigations of the tongue surface in wild animals are scarce and so far have been conducted e. g. on a newborn individual of the Asian black bear, and the panther, and an adult bush dog (Emura et al. 2000; Emura et al. 2001). The aim of the present study in SEM is to examine the location and morphology of lingual papillae on the dorsal surface of the tongue in the silver fox, which is a subspecies of the American fox (Vulpes vulpes fulva, Desmarest,
182o).
Material and methods This study was performed on a total of 8 tongues of adult silver foxes. Immediately after slaughtering, the tongues were dissected and washed in saline. Samples of the apex, body and root of the tongue were fixed in 2.5% glutaraldehyde in 0.1 M cacodylate buffer at 4 °C for 3 hours. After rinsing in the cold 0.1 M cacodylate buffer the samples were postfixed in 1% osmium tetroxide at 4 °C. After the dehydration of tissues in the alcohol and acetone series and critical point drying (CO2) the probes were mounted on aluminum stubs covered with carbon tabs and sputtered with a gold coat. Specimens were examined under a scanning electron microscope LEO 435 VP at 15 kV. 0940-96021041186102-I 79 $30.0010
Results The tongue in the silver fox is elongated with a rounded flat apex. It is approximately 7-8 cm in length. Macroscopically a distinct narrow median groove dividing the tongue into two symmetric parts may be seen on the dorsal surface of the apex and the body of the tongue. The groove disappears at the root of the tongue in front of the vallate papillae.
The apex and body of the tongue in the silver fox are covered by two types of lingual papillae, i.e. fungiform and filiform papillae. Approximately 12 fungiform papillae with a diameter of approx. 300 ~tm, were observed located close to one another, on the margin of the tongue apex (Fig. 1). The fungiform papillae on the surface of the apex and the body of the tongue are smaller, 150 gm in diameter (Fig. 2, 3). They are evenly distributed among filiform papillae and their density is 2-3/1 m m 2. The surface of fungiform papillae is slightly projected or flat. A total of 4-5 pores of the taste buds were observed on the surface of each papilla. Fungiform papillae were also sporadically observed on the root of the tongue, between conical papillae. Filiform papillae cover the apex and body of the tongue and the margins of the tongue (Fig. 1-3). The density of papillae ranges between 39 and 50/1 m m 2. In the structure of filiform papillae a basal part may be distinguished, approx. 130-150 pm in width, from which numerous processes branch off. The processes tilt towards the back of the tongue. Figures 2 and 3 present filiform papillae characteristic of the apex and body of the tongue. In the posterior part of the filiform papilla there is a bigger main process resembling a thorn, with a length of up to 250 gin, whereas 9-12 narrow accessory processes with a sharpened tip and a length of approx. 100 ~tm are observed on the anterior part of the papilla. The accessory processes of the filiform papillae become gradually reduced to 1 main and 2-3 smaller ones towards the root of the tongue (Fig. 4). Filiform papillae with a reduced number of accessory processes are also observed on the margin of the tongue apex (Fig. 1). In the posterior part of the body and on the root of the tongue, forming the pharyngeal wall, three types of lingual papillae may be distinguished, i.e. conical, vallate and foliate papillae. Conical papillae surround the area of the vallate papillae and cover the whole surface of the tongue root (Figs. 5, 6). These papillae are larger than filiform papillae. The width of conical papillae at the base reaches approx. 200 pm. The height of the papillae increases towards the pharynx, reaching ca. 750 pm. The
Fig. L Scanning electron micrograph of the apex of the tongue in the silver fox. On the margin of the apex, fungiform papillae (Fu) and filiform papillae with reduced processes (arrows) are visible. The dorsal surface of the lingual apex is covered by filiform papillae (Fi). x 225 Fig. 2. Scanning electron micrograph of the dorsal surface of the body of the tongue in the silver fox. Round fungiform papillae are scattered among filiform papillae with numerous accessory processes, x 68 Fig. 3. A higher magnification of the dorsal surface of the anterior part of the lingual body in the silver fox. The accessory processes (ap) and main process (mp) directed towards the back of the tongue arise from the base of the filiform papilla. Fu = fungiform papilla, x 238
180
In the anterior part of the tongue root in the silver fox there are 2 pairs of vallate papillae, 1.4-1.0 m m in diameter. The 2 pairs of vallate papillae are on oblique lines in a V form on the root of the tongue (Fig. 5). In some individuals the papillae of the anterior pair are slightly bigger. Each vallate papilla and its gustatory groove are surrounded by 6-7 conical papillae, partly fused at the base. The surface of the vallate papillae is smooth. In one individual, shallow grooves were observed on the surface of the anterior pair of vallate papillae. On the margins of the posterior part of the tongue body, next to the palatoglossal arch of the soft palate, small foliate papillae are found, formed from 4-5 laminae approx. 300-450 gm in width (Fig. 8). On the border between the margin and the dorsum of the tongue, the laminae fused with the bases of conical papillae.
density of conical papillae varies. Near vallate papillae it is approx. 20/1 m m 2, whereas in the posterior part of the root, conical papillae are more widely spaced and their density is only 5-6/1 m m 2. In the anterior part of the base, in conical papillae, single, round openings of lingual glands with the diameter of 10 ktm were observed on the root of the tongue (Fig. 6, 7).
Discussion Observations of the dorsal surface of the tongue in the silver fox under a scanning electron microscope made it possible to distinguish three types of gustatory papillae and two types of mechanical papillae. Mechanical papillae, among which filiform and conical papillae were found, are the most numerous on the tongue of the silver fox. Their function is connected with the transporting and swallowing of comminuted food to the pharynx. Filiform papillae are found on the dorsum of the apex and the body of the tongue, and gradually - as a result of the reduction of accessory processes on the tongue root, they are replaced by the more massive conical papillae covering the tongue as far as the pharynx. A similar distribution of filiform and conical papillae was reported in the dog and in the bush dog (Iwasaki and Sakata 1985; E m u r a et al. 2000). In the fox, similarly to the dog, filiform papillae, primarily in the anterior part of the tongue, undergo a characteristic division into processes, of which one - the posterior process - is dominant. Such a type of structure in filiform papillae is common in the Carnivora,
Fig. 4. A higher magnification of the posterior part of the lingual body in the silver fox. The filiform papillae are larger and their accessory processes (arrows) are reduced in the anterior part of each papillae. × 120 Fig. 5. Scanning electron micrograph of the anterior part of the root of the silver fox. The surface of the mucosa is covered by conical papillae (Co). Two vallate papillae (Va) are visible. The larger conical papillae surrounding the groove of the vallate papillae are partly fused, x 65 Fig. 6. Scanning electron micrograph of the conical papillae on the posterior part of the root of the tongue in the silver fox. Note the opening of the lingual glands on the anterior surface of the base of the conical papillae (arrows). × 310 181
as has been found not only within the Canidae family, but also in representatives of other families, i. e. in the family Felidae (Chamorro et al. 1987). It needs to be emphasized that filiform papillae with numerous, but identical processes, are observed in omnivorous animals, such as the pig, as well as some primates (Kobayashi et al. 1995, 1997). The distribution of gustatory papillae, i.e. fungiform, vallate and foliate papillae in the silver fox also closely resembles the arrangement of these lingual papillae in the dog (Iwasaki and Sakata 1985). The present observations showed a concentration of the fungiform papillae at the top of the tongue. These papillae are two times larger than those scattered on the body of the tongue and probably allow the animals to sample and taste food. The number and arrangement of the 4 vallate pa-
pillae, observed in the fox, are similar to those observed in the dog and the cat (Iwasaki and Sakata 1985; Chamorro et al. 1987). It should be pointed out that vallate papillae of the silver fox are also surrounded by partly fused conical papillae. As is the case in results from previous studies the number of vallate papillae in carnivorous animals varies. According to Emura et al. (2000) in the bush dog closely related to the dog, on each side of the tongue there are 5 vallate papillae, while each papilla is completely surrounded by a continuous pad. A larger number of vallate papillae was observed in other investigated carnivorous species. Thus, in the Asian black bear there are 7-8 papillae, whereas in the panther there are 10 papillae in all (Emura et al. 2000, 2001). The third type of gustatory papillae found in the fox are small foliate papillae. They exhibit a typical laminar structure previously found to be common in mammals (Chammoro et al. 1987; Kobayashi 1992). Taking into consideration the observations reported by Chammoro et al. (1987), who found digitiform foliate papillae in the cat, it may be supposed that morphological variability of these papillae is found in the carnivores. Summing up the results of our observations, it may be stated that in the silver fox the distribution and types of lingual papillae are similar to those in the other species of the Carnivora belonging to the family Canidae.
References
Fig. 7. A higher magnification of the opening of the lingual glands (arrow). On the cornified cells of the surface of the lingual epithelium (C) a delicate pattern of microridges were observed, x 2240 Fig. 8. Scanning electron micrograph of the foliate papilla (+-Fo--+) on the margin of the body of the tongue in the silver fox. The 5 laminae of the papilla are divided by an elongated grooves. In the dorsal part of the papilla the laminae fuse with the base of the conical papillae (Co). x 111
Boshell JL, Wilborn WH, Singh BB (1982) Filiform papillae of cat tongue. Acta Anat 114:97-105 Chamorro CA, Sandoval J, Fernandez JG, Fernandez y P de Paz G (1987) Estudio comparado de las Papillas linguales del Gato (Felis catus) y del Conjeo (Oryctolagus cuniculus ) mediante el Microscopio electronico de barrido. Anat Histol Embryol 16:37--47 Emura S, Tamada A, Hayakawa D, Chen H, Shoumura S (2000) Morphology of the dorsal lingual papillae in the bush dog (Speothos venaticus). Okajimas Folia Anat Jpn 77:137-141 Emura S, Hayakawa D, Chen H, Shoumura S (2001) Morphology of the dorsal lingual papillae in the newborn panther and asian black bear. Okajimas Folia Anat Jpn 78:173-178 Iwasaki S, Sakata K (1985) Scanning electron microscopy of the lingual dorsal surface of the beagle dog. Okajimas Folia Anat Jpn 62:1-14 Iwasaki S, Miyata K (1989) Fine structure of the filfform papilla of beagle dog. J Morphol 201:235-242 Iwasaki S (2002) Evolution of the structure and function of the vertebrate tongue. J Anat 201:1-13 Iwasaki S (1992) Fine structure of the dorsal lingual epithelium of the domestic, newborn kitten, Felis catus. Anat Anz 174: 293-300 Kobayashi K, Miyata K, Iino T (1987) Three-dimensional structures of the connective tissue papillae of the tongue in newborn dogs. Arch Histol Jpn 50:347-357 Kobayashi K, Miyata K, Iwasaki S, Takahashi K (1988) Three dimensional structure of the connective tissue papillae of cat lingual papillae. Jpn J Oral Biol 63:719-731
182
Kobayashi K (1992) Stereo architecture of the interface of the epithelial cell layer and connective tissue core of the foliate papillae in the rabbit tongue. Acta Anat 143:109-117 Kobayashi K, Kamakura M, Takahashi M (1995) Comparative observations on lingual papillae and their connective tissue cores in three primates. A scanning electron microscopic study. It J Anat Embryol 100:340-358 Kobayashi K, Kumakura M, Yoshimura K (1997) Stereo structural differences of lingual papillae and their connective tissue
cores in three kinds of artiodactyls. In: Recent Advances in Microscopy of Cells, Tissues and Organs. Motta PM (Ed), pp 357-361 Thome H (1999) Mundh6hle und Schlundkopf. In: Nickel R, Schummer A, Seiferle E. Lehrbuch der Anatomie der Hanstiere. Bd II, 8. Aufl., Parey Buchverlag: Berlin, pp 20-102
Accepted October 20, 2003
183