Gross anatomy, histology and palatine prints of the hard palate of the Philippine carabao (Bubalus bubalis L.)

Eighty-one Philippine carabaos (Bubalus bubalis L.) were used to describe the gross anatomy and histology of the hard palate and the palatine prints obtained from it. The hard palate and its bony support formed the roof of the oral cavity proper. It was covered by a thick mucosa fashioned into a pair of dental pads rostrally and a variable number of transverse ridges caudally. A median palatine raphe separated the left from the right rows of palatine ridges. Generally, the mucosa of the rostral third, dental pads and incesive papilla were pigmented. Patches of pigmentation of variable sizes, shapes, and number were noted in the mucosa of the middle and caudal regions of the hard palate. No two hard palates had similar patterns of mucosal pigmentation. Except for the middle region of the hard palate and the encisive papilla which were wider (P0.05) in the female than in the male carabaos, the gross anatomy of the hard palate of male carabaos resembled those of females. Histologically, the hard palate was composed of tunica mucosa and a lamina propria-submucosa. The mucosa of the hard palate was lined by a thick, highly keratinized ephithelium. In both sexes, the epithelium and the stratum corneum appeared thickest in the dental pad. The lamina muscularis mucosae was absent. The tunica propria-submucosa was composed of a network of dense collagen fibers oriented in different directions. The palatine glands were present in the caudal region of the hard palate. They were simple tubuloacinar mixed glands with mucous acini predominating. The secretory adenomeres reacted strongly to mucicarmine, periodic acid-Schiff and alcian blue (pH 2.5), indicating the presence of mucin, sulfated mucopolysaccharides and acidic mucosubstances, respectively. However, only a weak reaction was observed with alcian blue (pH 1.0). The hard palates of male and female carabaos closely resembled each other histologically. A print similar to human fingerfrints and muzzle prints in the carabao and cattle was taken from the hard palate of the carabao. The palatine print showed almost all features seen in the hard palate of the carabao. No two prints were identical, which may suggest that it can be used as an alternative method for carabao identification