Studies on the Skeleton of Japanese Serows (Capricornis crispus) IV. Bones of the Head (cranial and facial bones)

The bones of the head were investigated, following the reports on the skeleton of the appendicular and the trunk of the Japanese serow (J. Fac. Agric., Shinshu Univ. vol. 20, 173;1983, vol. 21, 59 and 119;1984). 1. The Nomina Anatomica Veterixiaria 2nd Ed. (1972) divides the skull into the cranial and the facial bones. The cranial bones of the Japanese serow were composed of the occipital, interparietal, basisphenoid, presphenoid, pterygoid, temporal, parietal, frontal, ethomoid and vomer. The facial bones of the animal were composed of the nasal, ventral nasal concha, maxilla, lacrimal, incisive (premaxilla), palatine, zygomatic, mandibule and hyoid. 2. In both male and femal Japanese serows, the skull had relatively small paired horns (cornual process of the frontal bones). The cranial vault of the Japanese serow was very thin dipoe, while that of the domestic goat was thick. The breath across the zygomatic arch was the widest in the skull of the Japanese serow. The position of the orbital cavity in the skull of the Japanese serow was more rostral part than that of the domestic sheep. The sutures in the skull of the Japanese serow were a more serrated appearance than they did in the domestic goat and sheep. 3. The cranial bones of the Japanese serow were distinguished from those of the domestic goat and sheep in the following points: Occipital Bone; squamous part, nuchal crest, external occipital protuberance, external occipital crest, foramen magnum, occipital condyles, paracondyloid process (jugular process was used on many anatomical textbooks of the domestic animals), muscular tubercles. Presphenoid and Basisphenoid Bones; ala, optic groove, optic canal, sella turcica, dorsum sellae, foramen ovale, foramen orbitorotundum. Pterygoid Bone; pterygoid incisure, hamulus. Temporal Bone; petrous part, mastoid process, tympanic bulla, external acoustic meatus, foramen lacerum, temporal crest, zygomatic process, mandibula fossa. Parietal Bone; temporal line, sulcus sinus sagittalis dorsalis. Frontal Bone; cornual process, nasal margin. Ethmoid Bone; crista galli, middle nasal concha. Vomer; length. 4. The facial bones of the Japanese serow were distinguished from those of the domestic goat and sheep in the following points: Nasal Bone; length, suture with maxilla, occasionally two parts by deep notch in the anterior end. Lacrimal Bone; external lacrimal fossa (infraorbital fossa), lacrimal bulla. Maxilla; facial tuberosity, foramen infraorbitale, suture with incisi bone, palatine process. Ventral Nasal Conchal Bone; size. Incisi Bone; palatine process. Palatine Bone; sphenopalatine notch, major and minor palatine foramina. Zygomatic Bone; antero-ventral border of orbita. Mandibula; mental foramen, mandibular tuberosity (near the junction of the body and the rami), mandibular rami, coronoid process, condyloid process, mandibular head (caput mandibulae), mandibular foramen. 5. The canals and foramina in the skull of the Japanese serow were investigated as follows: Occipital Bone; foramen magnum, canalis nervi hypoglossi, canalis condylaris, foramen mastoideum, foramen jugulare. Presphenoid and Basisphenoid Bones; foramen ovale, foramen orbitorotundum, canalis opticus. Temporal Bone; foramen lacerum, meatus temporalis, foramen retroarticulare, porus acusticus externus, porus acusticus internus, canalis musculotubarius, foramen stylomastoideum, canalis facialis, canaliculus tympanicus. Frontal Bone; foramen ethmoidale, foramen supraorbitale, canalis supraorbitalis. Ethmoid Bone; lamina cribrosa (cribriform foramina). Lacrimal Bone; foramen lacrimale, canalis lacrimalis. Maxilla; foramen infraorbitale, canalis infraorbitalis, canalis alveolaris, foramina alveolaria, foramen maxillare. Palatine Bone; foramen palatinum caudale, foramen palatinum majus, canalis palatinus major, choanae, canalis nasolacrimalis, foramen sphenopalatinum, foramina palatina minora. Mandibula; foramen mandibulae, canalis mandibulae, foramen mentale. The foramen lacerum in the skull of the Japanese serow was presented obviously, while the foramen was absent in the domestic goat, sheep and cattle on the Nomina Anatomica Veterinaria. In this study, an anatomical investigation and the first skeletal atlas of the Japanese serow were completed. The nomenclature was based on the Nomina Anatomica Veterinaria Japonica (1981).