Age estimation in the harbour seal (Phoca vitulina) based on the closure of skull sutures and synchondroses.

Age estimation of individuals is an important tool for the management of marine mammals and is mostly done by microscopic analysis of growth layer groups (GLGs) in teeth (cementum and dentin) and bone. The present study evaluated the use of sutural and synchondrosal closure in the skull of the harbour seal (Phoca vitulina) as a potential non-destructive alternative for age estimation. For that, we scored the ectocranial closure of 12 selected sutures and synchondroses in a sample of 303 Eastern Atlantic harbour seals (P.

Age-related changes in size, bone microarchitecture and volumetric bone mineral density of the mandible in the harbor seal (Phoca vitulina).

Detailed knowledge of age-related changes in the structure and mineralization of bones is important for interpreting osseous changes in wild mammals caused by exposure to environmental contaminants. This study analyzed mandibular size, microarchitecture and volumetric bone mineral density (vBMD) in harbor seals (n = 93, age range 0.5 months to 25 years) from the German North Sea.

Dental pulp exposure, periapical inflammation and suppurative osteomyelitis of the jaws in juvenile Baltic grey seals (Halichoerus grypus grypus) from the late 19th century.

The systematic analysis of museum collections can provide important insights into the dental and skeletal pathology of wild mammals. Here we present a previously unreported type of dental defect and related skull pathology in five juvenile Baltic grey seals that had been collected in the course of a seal culling program along the Danish coast in 1889 and 1890. All five skulls exhibited openings into the pulp cavities at the crown tips of all (four animals) or two (one animal) canines as well as several incisors and (in one animal) also some anterior premolars.

Dental anomalies and lesions in Eastern Atlantic harbor seals, Phoca vitulina vitulina (Carnivora, Phocidae), from the German North Sea.

Skulls of 1,901 Eastern Atlantic harbor seals (Phoca vitulina vitulina) were systematically studied for externally visible dental anomalies and lesions. The sample comprised 927 males and 974 female individuals, with age at death ranging between 1 week and 25 years. Most of the skulls originated from animals collected in 1988, when the population suffered from a mass mortality event caused by the phocine distemper virus (PDV).

Osteoarthritis of the temporomandibular joint in the Eastern Atlantic harbour seal (Phoca vitulina vitulina) from the German North Sea: a study of the lesions seen in dry bone.

Background: Pathological changes and resulting functional impairment of the temporomandibular joint (TMJ) can substantially affect physical condition, morbidity, and mortality of wildlife species. Analysis of TMJ disorders is therefore of interest for the characterization of the health status of populations of wild mammals. This paper, for the first time, analyses the prevalence of TMJ osteoarthritis (TMJ-OA) and the spectrum of osteoarthritic bone lesions of the TMJ in the Eastern Atlantic harbour seal (Phoca vitulina vitulina), applying a standardized scoring system.

Mineral Apposition Rates in Coronal Dentine of Mandibular First Molars in Soay Sheep: Results of a Fluorochrome Labeling Study.

We studied the spatio-temporal variation of mineral apposition rate (MAR) in postnatally formed coronal dentine of mandibular first molars from Soay sheep repeatedly injected with different fluorochromes. MAR declined along the cuspal to cervical crown axis, and from early to late formed dentine, that is, from the dentine at the enamel-dentine-junction (EDJ) to the dentine adjacent to the dentine-pulp-interface (DPI). Highest mean MARs (about 21 µm/day) were recorded in cuspal dentine formed in the period of 28-42 days after birth.