Neuron-specific enolase (NSE), a brain specific isoenzyme of the glycolytic enzyme, is characterized by its consistent occurrence in the cytoplasm of mature neurons. The purpose of the present study was to investigate the expression of NSE in the developing tongue of Korean native goats. The tongues of the fetuses were removed from 2- to 4-year-old female Korean native goats by caesarean section performed under general anesthesia. The expression of NSE in the developing tongue of goat fetuses (60, 90, 120, and 150 days) was studied using immunohistochemistry. In 60-day-old fetuses, NSE-immunoreactivity (IR) exhibited weak appearance in lamina propria of the basal portion and the apical epithelia of the tongue. In 90-day-old fetuses, NSE-nerve fibers were extended in the core part of connective tissue, and primordia of the taste buds was moderately positive. In 120-day-old fetuses, NSE-IR was strongly expressed in taste buds and gustatory nerve fibers. In neonates, the taste buds of vallate papillae were strongly positive for NSE, and development of nerve fibers was synapsed with connective tissue of well innervated taste buds. These results indicate that NSE expressions were associated with the sign of nerve innervation in prenatal development of goat tongues and NSE may be a useful neuronal marker to understand the development of gustatory nerve innervations.

The purpose of this study was to explore the morphologi- cal characteristics of developing lentiform papilla (LP) in Korean native goats by scanning electron microscopy (SAM). Tongues were removed from fetuses on days 90, 120, neonates, and juveniles on days 30, 60, 90, 120, 150, and 180. In prenatal development, the primordia of LP in 90-day-old fetuses were round and spotted on the inner most part of the torus linguae of the tongue. Primordia of LP in 120-day-old fetuses also had a lens-like shape. In neonates, LP displayed similar features as the adult one. In postnatal juveniles on days 30 and 60, LP continually increased in size without much difference in structure compared to that of neonates. By postnatal day 90, detached pieces of keratinized super- ficial epithelia were observed. Microridges and microplicae were well developed on the epithelial surface of LP in 60- to 120-day-old goats. The lengths of LP were 476~514 μm in neonates, 687~962 μm in the weaning period of 60-day- old goats, and 1,068~1,567 μm in the maturing period of 180-day-old goats. These findings indicate that goat LP has different sizes and shapes from those of other species during development.

The aim of this study was to investigate the morphological development pattern of conical papilla (CP) during prenatal and postnatal periods in native Korean goats by scanning electron microscopy. Tongues were removed from fetuses on days 90, 120, and neonates and from juveniles on days 30, 50, 60, 75, 90, 120, 150, and 180 after birth. The lengths of CP were 194~240 μm in neonates, 335~485 μm in the weaning period of 60-day-old goats, and 526~662 μm in the maturing period of 180-day-old goats. The primordia of CP in 90-day-old fetuses, shaped like mountain berry, were sprouted. The CP of 120-day-old fetuses was a cylinder shape with an apex whose center was slightly concave and the margin was sticking up like a low fence. The CP of neonates was empty inside and the secondary papillae were irregularly arranged fence-like structures on it. In 60-day-old goats, CP was an obliquely sectioned cylinder shape compacted in inner surface; the shapes of CP varied in 120-day-old goats, and had a smooth surface. A low elevation of CP was observed in 150- and 180-day-old goats. The microridges, microplicae, and micropits were well developed on the epithelial surface of lingual papillae in 60- to 120-day-old goats. These findings indicate that CP of goats has a variety of sizes and shapes during development.

The purpose of the present study was to investigate the morphological characteristics of the developing vallate papillae (VP) of Korean native goats using scanning electron microscopy. In prenatal development of the VP, primordia of the VP were observed and the moat was shallowly spread in 60-day-old fetuses. The moat of the vallate papillae was shallowly spread and still undifferentiated in 90-day-old fetuses. The trench wall of the moat of the VP was well developed in 120-dayold fetuses. In neonates, the moat of the VP was more widely and deeply engraved and VP were developed as completely as those of adults. In postnatal development, VP were observed to have continually increased in size with slight morphological changes until 90-days after birth. Taste pores of the VP were shaped like flower leaves in 120-days after birth. The microridges and microplicaes were well developed on the epithelial surface of the VP in goats ranging from 120-day-old fetuses to 120-day-old postnatal animals. These results suppose that the sensing ability for gestation of VP was already well developed by the time of its birth and VP were differentiated into a variety of different shape and size during development.