The aim of the research was to determine the number of teeth, their arrangement in the lower and upper dental arches and the manner of teeth placement in dental alveoli of alveolar processes respective for facial bones in brachycephalic dogs. Investigations were conducted on 45 adult dogs of various age and both sexes. Morphotype qualification was based on skull index ZyZy × 100/AP. The pattern of canine permanent dentition that is most common and widely approved as correct was described as 3142/3143. The total number of permanent teeth amounts to 42. Only in one (2.22%) out of 45 observed dogs a complete dentition in both dental arches was present, as in the formula above. Full dentition in the lower dental arch - was observed only in 6.67% of studied specimen and in the upper dental arch in 42.22% of dogs. The accepted number of permanent cheek teeth in dogs is 6 in the upper dental arch and 7 in the lower dental arch. The studies performed show that in brachycephalic specimen the reduction of these teeth and rotation related to alveolar processes are common. Own observations suggest that the following 3132/3132 should be recognized as a correct formula of permanent teeth in this morphotype.
The goal of this study was to determine the frequency of anomalies in incisor teeth depending on the horse’s age, sex, diet, diseases and floating frequency. A total of 255 horses from three Polish voivodeships, Kuyavian-Pomeranian, Greater Poland and Upper Silesia, were examined. The testing of incisor teeth was non-invasive and protocol-based. The most common defects were sharp edges of incisors in the maxilla and mandible, as well as a shortened mandible in relation to the maxilla. A relationship was proved between incisor anomalies and the horses’ age, floating frequency and bad habits. Anomalies of incisors are a common problem in horses in Poland, but they do not cause serious problems in the use of these animals.
The close phylogenetic relatedness among eels and their many species often necessitates applying genetic studies (PCR-RFLP) to identify the various species within the order Anguilliformes. This article presents a method for differentiating between European and Japanese eel based on the dentition of the upper jaw and the mouth cavity vault (vomer section). In European eel the row of teeth at the edge of the jaw is wider and has more teeth in comparison to that of the Japanese eel. The lengths and widths of the middle strip of the mouth cavity vaults are longer and wider in European eel than in Japanese eel.
We describe a partially crushed skull and dentaries of a sub-adult individual of Daulestes nessovi sp. n., from the Coniacian of Uzbekistan. This is the earliest known eutherian skull (about 87 Ma) and the sixth genus of Cretaceous eutherians in which a skull is available. Because the skull of D. nessovi is sub-adult, certain plesiomorphic features may be ontogenetic and should be interpreted with caution. Four upper premolars and five lower premolariform teeth were in use (possibly to become four lowers when fully adult). The upper cheek-teeth have winged conules; M2 has large parastylar and small metastylar projections. Pre- and postcingula are lacking on DP4 and the upper molars. The talonids of dp4-m2 are about 90% as wide as the trigonids, with widely separated entoconid and hypoconulid. The skull has a large sphenorbital fissure, no foramen rotundum, and apparently no pterygoid process of the sphenoid. A large orbital wing of the palatine prevents maxilla-frontal contact within the orbit. The zygomatic arch is slender. The cochlea has one full turn, with an expanded apex, which suggests that a lagena might have been present. A large malleus with a robust anterior process, and a large promontorium may be due to young age of the individual or a primitive retention, as in the platypus. Because of the similarity to Asioryctidaem both cranial structure and dentition, we assign Daulestes tentatively to Asioryctitheria Novacek et al. 1997, family incertae sedis.
The present research is unique. Its purpose was to prove the suitability of X-ray techniques for diagnosis of pathological changes of wild ruminant skeletons. The most interesting cases were chosen, among which two had very similar changes visible in the submaxilla area. The macroscopic examination did not allow for a closer estimation of the character changes. The X-ray examination revealed a wide range of radiological symptoms by means of which the final diagnosis could be made. Cystis folicularis, despite great similarity of changes, clearly differed on X-ray pictures from the overgrowth of shank bone tissue caused by osteoblastic stimulation of bone tissue injury background. The third case showed typical radiological symptoms of the inflammatory state (ostitis), infection background, as well as a possibility of differential diagnosis.
Morphological analysis of horse teeth, which defines a universal dental scheme of changes occurring with age on the incisors, can be useful not only in determining the age of the horse, but also in estimating the somatic maturity of horses of various breeds. The aim of the study was to compare changes on the incisors of Arabian and Anglo-Arabian horses, and to establish the frequency of errors in age determination based on the appearance of teeth. It was found that the percentage of errors in age determination based on the appearance of teeth was higher for Arabian mares compared to Anglo-Arabian ones. The age of Arabian mares was more frequently overestimated than underestimated, and the difference was highly significant. The method used for age determination proved most reliable during the disappearance of cups. It was the least useful during the replacement of milk incisors by permanent incisors and during the change in the shape of their occlusal surface, when the age of Anglo-Arabian horses was significantly more frequently underestimated than overestimated. On the basis of changes in the dentition of these two breeds, it can be concluded that the processes of eruption, exchange, and abrasion of incisors in Arabian mares occurs faster, which shows that they reach somatic maturity earlier than Anglo-Arabian mares.