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Dental anomalies in wild and domestic Sus scrofa in Illinois

100%

Feldhamer G. A. , McCann B. E.

nr 1

The cleaned skulls of 39 wild and 30 domestic pigs from southern Illinois (USA) were assessed for dental anomalies including polydonty, oligodonty, misalignment, and rotation. Dental anomalies occurred in 16 wild and 15 domestic pigs. Oligodonty (either bilateral or unilateral) was the most common anomaly, occurring in 9 wild (23.1% of the sample) and 15 (50%) domestic pigs. In 22 of the 24 individuals exhibiting oligodonty, this anomaly involved the lower first premolar (P1. Given the placement of P1, oligodonty may reflect a trend toward reduction of the dental arcade from the primitive eutherian number. Domesticated species are reported to have more anomalies than wild counterparts because of inbreeding. We found no difference in the number of dental anomalies between domestic and wild pigs.

Loss of the third upper premolar in Suncus murinus and its relation to jaw size

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Natori M. , Shigehara N.

tom 42

nr 1

Musk shrew Suncus murinus (Linnaeus, 1766) has a very reduced P3, and it is often missing. Hanamura (1985), based on a sample from Okinawa Island, proposed that the high incidence in P3 loss was a distinguishing characteristic of musk shrew. However, while the Okinawa population lacked P3 in 26 of 95 individuals (27.4%), specimens from Taiwan showed no P3 loss. Thus, the high incidence of P3 loss is not one of distinguishing characteristic of musk shrews. In the Okinawa sample, P4-M3 length vs palatal length in the group with P3 on both sides was significantly greater than that without P3. The relationship between the P4-M3 and palatal lengths showed negative allometry (Okinawa population with P3: y = 0.18 + 0.67a:; Okinawa population without P3: y = 0.21 + 0.67x; Taiwan population: y = 0.15 + 0.68x). Taiwan population had a greater P4-M3 length relative to palatal length than did the Okinawa population because palatal length was greater in the former. These findings suggest that, as in the case of human third molars, a reduction in upper jaw size is responsible for the loss of the third molar in the Okinawa musk shrews.

Craniometrical characteristics and dental anomalies in wolves Canis lupus from Latvia

84%

Andersone Z. , Ozolins J.

Acta Theriologica

2000

tom 45

nr 4

A total of 187 skulls (115 adult males and 72 adult females) of the wolf Canis lupus Linnaeus, 1758 hunted in Latvia between 1975-1999 were measured, using 19 craniometrical parameters. General cranial characteristics were similar to those described from the wolf populations of Belarus and Poland (the difference was not statistically significant). Sexual dimorphism in skull size was determined. Most of the skull parameters from north and east Latvia appeared to be slightly larger than those from the Kurland Peninsula, being isolated by large cities, rivers and deforested lands. Also, anomalies in tooth formula were described. Deviations from the normal tooth pattern were found in 9.5% skulls. Congenital oligodonty and polydonty was found in 7.9% skulls. Polydonty was observed in 71.4% cases of tooth anomalies. Tooth anomalies were more common in males than in females.

A supernumerary tooth and an odontoma attributable to Mammuthus primigenius [Blumenbach, 1799] [Mammalia, Proboscidea] from The Netherlands, and various related finds

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Van E. H.

nr 1-2

Two dental anomalies referable to Mammuthus primigenius (BLUMENBACH, 1799) are described. The first is a unilateral supernumerary tooth in a mandible with M3 in advanced wear (part I). A mandible with two supernumerary teeth from Otterstadt (Germany) was published earlier, but interpreted as an anomalous replacement of M2 by M3 (ADAM 1994). The discussion therefore focuses on the implications of this alternative theory and the arguments against it. On the basis of specimens in mandibles, some isolated finds of mammoth teeth from various locations in western Europe are tentatively presented as supernumerary. The second anomaly is a compound odontoma that developed around a normal M3. Previously published elephantid odontomas are discussed and a preliminary survey of their macroscopic characteristics as opposed to those of supernumerary teeth is presented. Some terminological problems arising from the imperfect morphological analogy between anomalies in human and elephantid dentitions are discussed.