Light and scanning electron microscopic study on the tongue and lingual papillae of the common raccoon, Procyon lotor

We observed the external surface and connective tissue cores (CTCs), after exfoliation of the epithelium of the lingual papillae (filiform, fungiform, foliate and vallate papillae) of the common raccoon (Procyon lotor) using scanning electron microscopy and light microscopy. The tongue was elongated and their two-third width was almost fixed. Numerous filiform papillae were distributed along the anterior two-thirds of the tongue and fungiform papillae were distributed between the filiform papillae. Eight vallate papillae that had a weak circumferential ridge were distributed in a V-shape in the posterior part of the tongue and numerous taste buds were observable in the circumferential furrows of vallate papillae. Weak fold-like foliate papillae were observable at the lateral edge in the posterior part of the tongue and a few salivary duct orifices were observable beneath the foliate papillae. An islet-like structure with numerous taste buds, was observable on the deep part of the salivary duct of foliate papillae. Large conical papillae were distributed at the posterior part and root of the tongue. After removal of epithelium, filiform papillae of CTCs were appeared to be a thumb or cone-like main core and associating several finger-like short accessory cores. These cores were surrounded an oval concavity. The main core was situated behind the concavity and associated with accessory cores. CTCs of fungiform papillae were cylinder-like with numerous vertically running ridges and with a few concavities seen at the top of the cores. CTCs of vallate papillae and their surrounded circumferential ridge were covered with numerous pimple-like protrusions. The lingual papillae of Common raccoon's tongue had morphological feature of carnivore species.

Light and scanning electron microscopic study on the tongue and lingual papillae of the Japanese badgers, Meles meles anakuma

We observed the three-dimensional structures of the external surface and connective tissue cores (CTCs), after exfoliation of the epithelium of the lingual papillae (filiform, fungiform and foliate papillae) of the Japanese badgers (Meles meles anakuma) using scanning electron microscopy and conventional light microscopy. Macroscopically, the tongue was elongated anterior-posteriorly and the apex rounded. Numerous filiform papillae and fungiform papillae were distributed all over the tongue except at the root. Seven vallate papillae were observed that had circumferential furrows and were arranged in V-shape. Numerous taste buds were observable in the furrows. Instead of foliate papillae, a lateral organ lacking taste buds was present on the lateral edge of the posterior tongue. Behind the vallate papillae, dome-like lingual tonsils that had globular tonsils were densely distributed in U-shaped arrangement. Rather long conical papillae were distributed around the vallate papillae. At the posterior end of the root of the tongue, lingual papillae were very much attenuated and only fold-like structure was seen. CTCs of filiform papillae had a main rod-like slender core and ovally arranged short accessory cores distributed around the main core. CTCs of fungiform papillae exhibited a columnar like appearance. The lingual papillae of Japanese badger's tongue fundamentally had morphological similarity with carnivore species, included the Pinnipedia.

Winter Hibernation and Body Temperature Fluctuation in the Japanese Badger, Meles meles anakuma

This study examined seasonal changes in body weight, hibernation period, and body temperature of the Japanese badger (Meles meles anakuma) from 1997 to 2001. Adult badgers showed seasonal changes in body weight. Between mid-December and February, badger activity almost ceased, as the animals remained in their setts most of the time. Adult male badgers were solitary hibernators; adult females hibernated either alone or with their cubs and/or yearlings. The total hibernation period of Japanese badgers ranged from 42 to 80 days, with a mean length of 60.1 days. Japanese badgers did not always spend the winters in the same sett, although they seldom changed setts during hibernation. I equipped a male cub with an intraperitoneally implanted data logger to record its body temperature between November and April, while the cub hibernated with its mother. Over the winter, the body weight of the cub decreased from 5.3 kg to 3.6 kg, a weight loss of 32.1%, and its body temperature ranged from 32.0 to 39.8 degrees C. The mean monthly body temperature was 35.1 degrees C in December, 34.8 degrees C in January, 35.9 degrees C in February, 37.1 degrees C in March, and 37.4 degrees C in April, so the monthly decrease in body temperature of this cub was not great. The results indicate that during hibernation, when body temperature is low, there is likely considerable economy of energy and a reduced demand for adipose reserves.