We studied enamel defects in mandibular cheek teeth of fallow deer from an enclosed population th... more We studied enamel defects in mandibular cheek teeth of fallow deer from an enclosed population that had grown far beyond the carrying capacity of its habitat. Macroscopic inspection revealed a high frequency of pathological enamel alterations in the permanent premolars and the third molar, which form late during dental development, while earlier forming teeth (deciduous premolars and first molar) were generally not affected. Macroscopic enamel alterations comprised opacity and posteruptive discoloration, loss of occlusal enamel ridges, and presence of enamel surface lesions. Backscattered electron imaging in the SEM revealed a marked hypomineralization and related increased porosity of the outer compared to the central and inner enamel portions in the affected teeth. In contrast, the enamel of the unaffected first molars showed a homogeneous high degree of mineralization. Microindentation hardness testing demonstrated a significantly reduced and highly variable hardness of the outer...
We analyzed pedicle bone from roe bucks that had died around antler casting or shortly before or ... more We analyzed pedicle bone from roe bucks that had died around antler casting or shortly before or during the rutting period. Pedicles obtained around antler casting were highly porous and showed signs of intense osteoclastic activity that had caused the formation of an abscission line. Following the detachment of the antler plus a portion of pedicle bone, osteoclastic activity in the pedicles continued for some time, and new bone was deposited onto the separation plane of the pedicle stump, leading to partial pedicle restoration. Pedicles obtained around the rutting period were compact structures. The newly formed, often very large secondary osteons, which had filled the resorption cavities, exhibited a lower mineral density than the persisting older bone. The middle zones of the lamellar infilling frequently showed hypomineralized lamellae and enlarged osteocyte lacunae. This indicates a deficiency in mineral elements during the formation of these zones that occurred along with peak antler mineralization. We suggest that growing antlers and compacting pedicles compete for mineral elements, with the rapidly growing antlers being the more effective sinks. The competition between the two simultaneously mineralizing structures is probably more severe in Capreolus capreolus than in other cervids. This is because roe bucks regrow their antlers during late autumn and winter, a period of limited food and associated mineral supply. The pedicle is a heavily remodeled bone structure with distinct seasonal variation in porosity. Pedicle remodeling differs in several aspects from the normal bone remodeling process in the mammalian skeleton.
Environmental Science and Pollution Research, 2021
We studied heavy metal levels in floodplain soils of the Innerste River in northern Germany and i... more We studied heavy metal levels in floodplain soils of the Innerste River in northern Germany and in the leaves of wild blackberries (Rubus fruticosus L. agg.) growing within and in adjacent areas outside the river floodplain. Heavy metal contamination of the Innerste floodplain is a legacy of historical metal ore mining, processing, and smelting in the Harz Mountains. The heavy metal (Cd, Pb, Zn, Cu, Ni, and Cr) contents of previously studied soil samples from eleven floodplain sites along the Innerste River were re-analyzed statistically, and the levels of these metals in blackberry leaves were determined at five sites. Mean concentrations in the floodplain soils were elevated by factors of 4.59 to 28.5 for Cd, 13.03 to 158.21 for Pb, 5.66 to 45.83 for Zn, and 1.1–14.81 for Cu relative to the precautionary limits for soils stipulated by the German Federal Soil Protection and Contaminated Sites Ordinance. Cadmium, Pb, Zn, Cu, and Ni levels in floodplain soils decreased markedly downs...
Detailed knowledge of age-related changes in the structure and mineralization of bones is importa... more 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. Bone microarchitecture and vBMD were assessed using high-resolution peripheral quantitative computed tomography (HR-pQCT). Significant differences were observed between the analyzed age classes (i) young juveniles (0.5-10 months), (ii) yearlings (12-23 months), and (iii) adults (12-25 years) for several of the variables, indicating an overall increase in cortical and trabecular area, cortical thickness and total and cortical vBMD with age. Furthermore, for juvenile animals (� 23 months), significant positive correlations with age were observed for mandible length and perimeter, cortical area, cortical thickness, trabecular separation, and total and cortical vBMD. The findings demonstrate a rapid increase in overall size, cortical dimensions and the degree of mineralization of the harbor seal mandible during the first two years after birth. Negative correlations with age existed for trabecular number and thickness as well as for trabecular bone volume fraction in the juveniles. The findings suggest a reduction in trabecular bone volume fraction with age, due to the bone trabeculae becoming thinner, less numerous and more widely spaced. Given the strong age dependence of most analyzed parameters, it is recommended to standardize samples with respect to age in future studies comparing microarchitecture and mineralization of harbor seal mandibles from different populations or different collection periods.
The systematic analysis of museum collections can provide important insights into the dental and ... more 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. The affected teeth showed wide pulp cavities and thin dentin. Pulp exposure had caused infection, inflammation, and finally necrosis of the pulp. As was evidenced by the extensive radiolucency around the roots of the affected teeth, the inflammation had extended from the pulp into the periapical space, leading to apical periodontitis with extensive bone resorption. Further spreading of the inflammation into the surrounding bone regions had then caused suppurative osteomyelitis of the jaws. The postcanine teeth of the pathological individuals typically had dentin of normal thickness and, except for one specimen, did not exhibit pulp exposure. The condition may have been caused by a late onset of secondary and tertiary dentin formation that led to pulp exposure in anterior teeth exposed to intense wear. Future investigations could address a possible genetic causation of the condition in the studied grey seals.
Skulls of 1,901 Eastern Atlantic harbor seals (Phoca vitulina vitulina) were systematically studi... more 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). Mean age (± SD) of females (6.7 ± 6.4 years) was higher (p = 0.002) than that of males (5.9 ± 5.2 years). In 264 individuals, one or more teeth were missing either congenitally (n = 26 animals, 1.4%) or due to intravital loss (n = 238 animals, 12.5%). One male exhibited congenital absence of all teeth (anodontia). As this animal had been reported to be almost hairless, the condition was tentatively diagnosed as a case of hypohidrotic ectodermal dysplasia. Males were more frequently (p = 0.002) affected by intravital tooth loss (15.0%) than females (10.2%). Supernumerary teeth were found in 3.4% of the skulls, with females (4.7%) showing hyperodontia more frequently (p < 0.001) than males (1.9%). Fifty-nine individuals (3.1%; 28 males, 31 females, p = 0.84) exhibited abnormal tooth morphology. Tooth fractures were noted in 40 seals (2.1%), with males being more frequently affected than females (p = 0.017). Periapical lesions were diagnosed in 143 skulls, with a tendency (p = 0.05) for males (8.7%) to be more frequently affected than females (6.4%). Enamel hypoplasia was not observed in the study sample. Analyzing the occurrence of dental anomalies and lesions in wild mammals can substantially contribute to an assessment of population health and thereby broaden the basis for effective species conservation and informed management decisions.
Сумський державний університет Резюме. У статті опрацьовано та докладно розглянуто сучасний літер... more Сумський державний університет Резюме. У статті опрацьовано та докладно розглянуто сучасний літературний матеріал стосовно ролі води в організмі та дегідратаційних порушень водного балансу, а саме: детально описані позаклітинний (ізота гіпоосмолярний), внутрішньоклітинний (гіперосмо-лярний) та загальний (як наслідок першого і другого варіантів) види зневоднення.
Morphology and histological structure of antlers grown after castration (performed on March 25) w... more Morphology and histological structure of antlers grown after castration (performed on March 25) were studied in six young fallow bucks. In the year after castration, antlerogenesis occurred during the species-specific time span, and the shape of the antlers, which remained permanently in velvet, was normal. During a cold period in DecembedJanuary, the distal parts of the antlers suffered from frostbite and were subsequently detached. The process of sequestration was similar to that leading to normal antler casting. The sequestration sites were soon covered with skin, but (limited) regrowth of antler tissue from the stumps was not observed before late Aprillearly May, i.e., the time of normal antler regeneration. Simultaneously, growth of knobby protuberances started on the surface of the antlers. Histological analysis of biopsies taken on December 20 in the year after castration revealed that the central parts of the antlers consisted of cancellous lamellar bone with mainly secondary osteons. Peripheral to this, the bone tissue (forming the protuberances) was of a more immature nature and exhibited larger intertrabecular spaces. The outermost layer consisted of woven bone formed by intramembranous ossification from the periosteum and was undergoing active growth and remodeling at the time of biopsy. Thus, bone formation at these sites occurred during a period when no antler growth is observed in normal fallow bucks. The velvet covering the bony protuberances was of normal appearance.
The developmental conditions for the growth of primary cranial appendages and secondary or subseq... more The developmental conditions for the growth of primary cranial appendages and secondary or subsequent antlers are discussed with special regard to ortho- and heterotopic double-head formation. We hypothesize that the cells of the pedicle periosteum, being derivatives of the initial or antlerogenic periosteum which is determined for the formation of primary cranial appendages, are equally endowed with special antlerogenic tendencies. The hormonally controlled activation of these tendencies is possible even if previous casting of the old antlers has not taken place, and no casting wound arises at the top of the pedicle. The fact that antler regeneration occurs regardless of previous detachment of the old antlers indicates that the stimulus for regeneration is not antler casting but the death of the velvet antler. Antler regeneration, like sequestration of the old antler, is thus hormonally suppressed for some months after velvet shedding.
American journal of physical anthropology, Jan 18, 2015
Recently, a lower than expected number of perikymata between repetitive furrow-type hypoplastic d... more Recently, a lower than expected number of perikymata between repetitive furrow-type hypoplastic defects has been reported in chimpanzee canines from the Fongoli site, Senegal (Skinner and Pruetz: Am J Phys Anthropol 149 (2012) 468-482). Based on an observation in a localized enamel fracture surface of a canine of a chimpanzee from the Taï Forest (Ivory Coast), these authors inferred that a nonemergence of striae of Retzius could be the cause for the "missing perikymata" phenomenon in the Fongoli chimpanzees. To check this inference, we analyzed the structure of outer enamel in three chimpanzee canines. The teeth were studied using light-microscopic and scanning-electron microscopic techniques. Our analysis of the specimen upon which Skinner and Pruetz (Am J Phys Anthropol 149 (2012) 468-482) had made their original observation does not support their hypothesis. We demonstrate that the enamel morphology described by them is not caused by a nonemergence of striae of Retzius ...
The relationships between age (range: 3 to 14 yr), mandibular bone fluoride level (marker of accu... more The relationships between age (range: 3 to 14 yr), mandibular bone fluoride level (marker of accumulated internal dose, range: 597 to 4680 mg F − kg −1 dry wt) and intensity of dental fluorosis (reflecting fluoride exposure during enamel formation) were studied in a sample of 53 fluorosed red deer from a fluoride-polluted area in the Czech-German border region (Ore mountains and their southern foreland). Assessment of the severity of dental fluorosis was performed for the 3 permanent premolars and 3 molars of one hemimandible per animal by using an ordinal measurement scale. For statistical analysis, the maximum tooth score of fluorosis (MTS) and the dental lesion index of fluorosis (DLI, sum of the six tooth scores per individual) were used. In the sample, both MTS (r s = 0.850) and DLI (r s = 0.813) were highly significantly (p <0.00001) correlated with bone fluoride content. A weaker correlation existed between age and bone fluoride content (r s = 0.322, p <0.05). The results demonstrate that in case of regional, long-term fluoride pollution, dental fluorosis (measured as MTS or DLI) can be used as a sensitive biomarker of fluoride exposure in deer and thus as an indicator of the level of environmental contamination by fluorides. In many countries, skulls and mandibles of wild deer are regularly and continuously collected by hunters. Assessment of the prevalence and severity of dental fluorosis in this material offers the opportunity for an efficient large-scale biomonitoring of environmental pollution by fluorides at very low cost.
only three males (two in period 1, one in period 4) stayed in the day roost all night. the other ... more only three males (two in period 1, one in period 4) stayed in the day roost all night. the other tracked animals left their day-roost for the first time between 25 and 220 minutes after sunset, and their last arrival at the day-roost occurred between 2 and 545 minutes before sunrise. Bats spent most of their nocturnal activity time foraging (overall mean: 79.7 % of nocturnal activity time). duration of nocturnal activity and nightly foraging time varied considerably over the four observation periods and were most extended in midsummer (period 3). this is a time of high spermatogenetic activity and steep increase in body mass (built-up of fat reserves), which leads to a particularly high food demand of male daubenton's bats during this period of the year. our results of an increased foraging activity during midsummer provide evidence in support of the view that food demand of male daubenton's bats is indeed highest during this time of the year.
ENCARNAÇÃO, J. A., U. KIERDORF, V. WOLTERS: Effects of age and season on body mass and reproducti... more ENCARNAÇÃO, J. A., U. KIERDORF, V. WOLTERS: Effects of age and season on body mass and reproductive condition in male Daubenton's bats (Myotis daubentonii). Vet. arhiv 76, S239-S249, 2006. ABSTRACT We analyzed the effects of age and season on body mass and reproductive condition in male Daubenton's bats (Myotis daubentonii) from a study area in central Germany, which were captured during April to October of the years 1998-2003. On first capture, animals (n=336) were banded and classified as either young of the year or adults (i.e. males ≥ 1 year of age). On recapture, animals first caught as young of the year could be assigned an exact age in years. Epididymal distension in young of the year indicated that some males had reached sexual maturity (defined as onset of spermatogenesis) already in their year of birth, while others did so in their second summer. Body mass and epididymal distension showed pronounced variation related to age and season, with highest values reached...
The periodic replacement of antlers is an exceptional regenerative process in mammals, which in g... more The periodic replacement of antlers is an exceptional regenerative process in mammals, which in general are unable to regenerate complete body appendages. Antler regeneration has traditionally been viewed as an epimorphic process closely resembling limb regeneration in urodele amphibians, and the terminology of the latter process has also been applied to antler regeneration. More recent studies, however, showed that, unlike urodele limb regeneration, antler regeneration does not involve cell dedifferentiation and the formation of a blastema from these dedifferentiated cells. Rather, these studies suggest that antler regeneration is a stemcell-based process that depends on the periodic activation of, presumably neural-crest-derived, periosteal stem cells of the distal pedicle. The evidence for this hypothesis is reviewed and as a result, a new concept of antler regeneration as a process of stem-cell-based epimorphic regeneration is proposed that does not involve cell dedifferentiation or transdifferentiation. Antler regeneration illustrates that extensive appendage regeneration in a postnatal mammal can be achieved by a developmental process that differs in several fundamental aspects from limb regeneration in urodeles.
We studied age-related variation in body mass and epididymal distension in male Daubenton's bats.... more We studied age-related variation in body mass and epididymal distension in male Daubenton's bats. Examination of data on epididymal distension in young of the year indicates that some reach sexual maturity by the year of birth, whereas others do so in their 2nd summer. Body mass and epididymal distension were positively correlated in young of the year and adults, suggesting that early sexual maturation and reproductive condition during later life are dependent on body condition. Older males tended to be heavier and in better reproductive condition than younger ones. Examination of our data suggests that physical and reproductive condition of males increase after the initial onset of fertility until 3 years of age. This late physical maturation is in line with other life-history traits characterizing long-lived bats as K-strategists among small mammals.
The study investigated developmental defects of the dental hard tissues and postmortem changes in... more The study investigated developmental defects of the dental hard tissues and postmortem changes in archaeological pig molars from Fais Island, Micronesia. The developmental defects of enamel were indicative of a disturbance of the secretory stage (accentuation of the incremental pattern, occurrence of Wilson bands and of hypoplastic defects) and the maturation stage of amelogenesis (hypomineralisation). Presence of coronal cementum in
Prevalence and intensity of enamel hypoplasia have been used as markers of generalized physiologi... more Prevalence and intensity of enamel hypoplasia have been used as markers of generalized physiological stress during dental development in a wide range of mammalian taxa. We studied cattle (Bos taurus) cheek teeth exhibiting morphological characteristics that are of relevance to the diagnosis of enamel hypoplasia in this and other bovid species. These characteristics were multiple, more or less horizontally arranged
Enamel is the most highly mineralized and durable tissue of the mammalian body. As enamel does no... more Enamel is the most highly mineralized and durable tissue of the mammalian body. As enamel does not undergo remodeling or repair, disturbances of enamel formation leave a permanent record in the tissue that can be used for life history reconstruction. This study reports light and scanning electron microscope findings on hypoplastic enamel defects, and on the chronology of crown growth in the molars of sheep and goats. A marked reduction of enamel extension rates in cervical compared with more cuspal crown portions of sheep and goat molars was recorded, with formation of the cervical 25% of the crown taking about the same time as that of the upper 75% of the crown. This explains the more frequent occurrence of enamel hypoplasia in cervical compared with upper and middle crown portions. Regarding the identification of hypoplastic enamel defects by external inspection, our results suggest a dependence on the type of defect and the associated presence of smaller or larger amounts of coronal cementum. Defects considered to reflect a slight to moderate impairment of secretory ameloblast function can normally be correctly diagnosed as they are not occluded by thick layers of cementum. In contrast, defects denoting a severe impairment of enamel matrix secretion can typically not be correctly identified because they are occluded by large amounts of cementum, so that neither depth nor extension of the defects can be assessed on external inspection. In these cases, microscopic analysis of tooth sections is required for a correct diagnosis of the hypoplastic enamel defects.
We studied enamel defects in mandibular cheek teeth of fallow deer from an enclosed population th... more We studied enamel defects in mandibular cheek teeth of fallow deer from an enclosed population that had grown far beyond the carrying capacity of its habitat. Macroscopic inspection revealed a high frequency of pathological enamel alterations in the permanent premolars and the third molar, which form late during dental development, while earlier forming teeth (deciduous premolars and first molar) were generally not affected. Macroscopic enamel alterations comprised opacity and posteruptive discoloration, loss of occlusal enamel ridges, and presence of enamel surface lesions. Backscattered electron imaging in the SEM revealed a marked hypomineralization and related increased porosity of the outer compared to the central and inner enamel portions in the affected teeth. In contrast, the enamel of the unaffected first molars showed a homogeneous high degree of mineralization. Microindentation hardness testing demonstrated a significantly reduced and highly variable hardness of the outer...
We analyzed pedicle bone from roe bucks that had died around antler casting or shortly before or ... more We analyzed pedicle bone from roe bucks that had died around antler casting or shortly before or during the rutting period. Pedicles obtained around antler casting were highly porous and showed signs of intense osteoclastic activity that had caused the formation of an abscission line. Following the detachment of the antler plus a portion of pedicle bone, osteoclastic activity in the pedicles continued for some time, and new bone was deposited onto the separation plane of the pedicle stump, leading to partial pedicle restoration. Pedicles obtained around the rutting period were compact structures. The newly formed, often very large secondary osteons, which had filled the resorption cavities, exhibited a lower mineral density than the persisting older bone. The middle zones of the lamellar infilling frequently showed hypomineralized lamellae and enlarged osteocyte lacunae. This indicates a deficiency in mineral elements during the formation of these zones that occurred along with peak antler mineralization. We suggest that growing antlers and compacting pedicles compete for mineral elements, with the rapidly growing antlers being the more effective sinks. The competition between the two simultaneously mineralizing structures is probably more severe in Capreolus capreolus than in other cervids. This is because roe bucks regrow their antlers during late autumn and winter, a period of limited food and associated mineral supply. The pedicle is a heavily remodeled bone structure with distinct seasonal variation in porosity. Pedicle remodeling differs in several aspects from the normal bone remodeling process in the mammalian skeleton.
Environmental Science and Pollution Research, 2021
We studied heavy metal levels in floodplain soils of the Innerste River in northern Germany and i... more We studied heavy metal levels in floodplain soils of the Innerste River in northern Germany and in the leaves of wild blackberries (Rubus fruticosus L. agg.) growing within and in adjacent areas outside the river floodplain. Heavy metal contamination of the Innerste floodplain is a legacy of historical metal ore mining, processing, and smelting in the Harz Mountains. The heavy metal (Cd, Pb, Zn, Cu, Ni, and Cr) contents of previously studied soil samples from eleven floodplain sites along the Innerste River were re-analyzed statistically, and the levels of these metals in blackberry leaves were determined at five sites. Mean concentrations in the floodplain soils were elevated by factors of 4.59 to 28.5 for Cd, 13.03 to 158.21 for Pb, 5.66 to 45.83 for Zn, and 1.1–14.81 for Cu relative to the precautionary limits for soils stipulated by the German Federal Soil Protection and Contaminated Sites Ordinance. Cadmium, Pb, Zn, Cu, and Ni levels in floodplain soils decreased markedly downs...
Detailed knowledge of age-related changes in the structure and mineralization of bones is importa... more 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. Bone microarchitecture and vBMD were assessed using high-resolution peripheral quantitative computed tomography (HR-pQCT). Significant differences were observed between the analyzed age classes (i) young juveniles (0.5-10 months), (ii) yearlings (12-23 months), and (iii) adults (12-25 years) for several of the variables, indicating an overall increase in cortical and trabecular area, cortical thickness and total and cortical vBMD with age. Furthermore, for juvenile animals (� 23 months), significant positive correlations with age were observed for mandible length and perimeter, cortical area, cortical thickness, trabecular separation, and total and cortical vBMD. The findings demonstrate a rapid increase in overall size, cortical dimensions and the degree of mineralization of the harbor seal mandible during the first two years after birth. Negative correlations with age existed for trabecular number and thickness as well as for trabecular bone volume fraction in the juveniles. The findings suggest a reduction in trabecular bone volume fraction with age, due to the bone trabeculae becoming thinner, less numerous and more widely spaced. Given the strong age dependence of most analyzed parameters, it is recommended to standardize samples with respect to age in future studies comparing microarchitecture and mineralization of harbor seal mandibles from different populations or different collection periods.
The systematic analysis of museum collections can provide important insights into the dental and ... more 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. The affected teeth showed wide pulp cavities and thin dentin. Pulp exposure had caused infection, inflammation, and finally necrosis of the pulp. As was evidenced by the extensive radiolucency around the roots of the affected teeth, the inflammation had extended from the pulp into the periapical space, leading to apical periodontitis with extensive bone resorption. Further spreading of the inflammation into the surrounding bone regions had then caused suppurative osteomyelitis of the jaws. The postcanine teeth of the pathological individuals typically had dentin of normal thickness and, except for one specimen, did not exhibit pulp exposure. The condition may have been caused by a late onset of secondary and tertiary dentin formation that led to pulp exposure in anterior teeth exposed to intense wear. Future investigations could address a possible genetic causation of the condition in the studied grey seals.
Skulls of 1,901 Eastern Atlantic harbor seals (Phoca vitulina vitulina) were systematically studi... more 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). Mean age (± SD) of females (6.7 ± 6.4 years) was higher (p = 0.002) than that of males (5.9 ± 5.2 years). In 264 individuals, one or more teeth were missing either congenitally (n = 26 animals, 1.4%) or due to intravital loss (n = 238 animals, 12.5%). One male exhibited congenital absence of all teeth (anodontia). As this animal had been reported to be almost hairless, the condition was tentatively diagnosed as a case of hypohidrotic ectodermal dysplasia. Males were more frequently (p = 0.002) affected by intravital tooth loss (15.0%) than females (10.2%). Supernumerary teeth were found in 3.4% of the skulls, with females (4.7%) showing hyperodontia more frequently (p < 0.001) than males (1.9%). Fifty-nine individuals (3.1%; 28 males, 31 females, p = 0.84) exhibited abnormal tooth morphology. Tooth fractures were noted in 40 seals (2.1%), with males being more frequently affected than females (p = 0.017). Periapical lesions were diagnosed in 143 skulls, with a tendency (p = 0.05) for males (8.7%) to be more frequently affected than females (6.4%). Enamel hypoplasia was not observed in the study sample. Analyzing the occurrence of dental anomalies and lesions in wild mammals can substantially contribute to an assessment of population health and thereby broaden the basis for effective species conservation and informed management decisions.
Сумський державний університет Резюме. У статті опрацьовано та докладно розглянуто сучасний літер... more Сумський державний університет Резюме. У статті опрацьовано та докладно розглянуто сучасний літературний матеріал стосовно ролі води в організмі та дегідратаційних порушень водного балансу, а саме: детально описані позаклітинний (ізота гіпоосмолярний), внутрішньоклітинний (гіперосмо-лярний) та загальний (як наслідок першого і другого варіантів) види зневоднення.
Morphology and histological structure of antlers grown after castration (performed on March 25) w... more Morphology and histological structure of antlers grown after castration (performed on March 25) were studied in six young fallow bucks. In the year after castration, antlerogenesis occurred during the species-specific time span, and the shape of the antlers, which remained permanently in velvet, was normal. During a cold period in DecembedJanuary, the distal parts of the antlers suffered from frostbite and were subsequently detached. The process of sequestration was similar to that leading to normal antler casting. The sequestration sites were soon covered with skin, but (limited) regrowth of antler tissue from the stumps was not observed before late Aprillearly May, i.e., the time of normal antler regeneration. Simultaneously, growth of knobby protuberances started on the surface of the antlers. Histological analysis of biopsies taken on December 20 in the year after castration revealed that the central parts of the antlers consisted of cancellous lamellar bone with mainly secondary osteons. Peripheral to this, the bone tissue (forming the protuberances) was of a more immature nature and exhibited larger intertrabecular spaces. The outermost layer consisted of woven bone formed by intramembranous ossification from the periosteum and was undergoing active growth and remodeling at the time of biopsy. Thus, bone formation at these sites occurred during a period when no antler growth is observed in normal fallow bucks. The velvet covering the bony protuberances was of normal appearance.
The developmental conditions for the growth of primary cranial appendages and secondary or subseq... more The developmental conditions for the growth of primary cranial appendages and secondary or subsequent antlers are discussed with special regard to ortho- and heterotopic double-head formation. We hypothesize that the cells of the pedicle periosteum, being derivatives of the initial or antlerogenic periosteum which is determined for the formation of primary cranial appendages, are equally endowed with special antlerogenic tendencies. The hormonally controlled activation of these tendencies is possible even if previous casting of the old antlers has not taken place, and no casting wound arises at the top of the pedicle. The fact that antler regeneration occurs regardless of previous detachment of the old antlers indicates that the stimulus for regeneration is not antler casting but the death of the velvet antler. Antler regeneration, like sequestration of the old antler, is thus hormonally suppressed for some months after velvet shedding.
American journal of physical anthropology, Jan 18, 2015
Recently, a lower than expected number of perikymata between repetitive furrow-type hypoplastic d... more Recently, a lower than expected number of perikymata between repetitive furrow-type hypoplastic defects has been reported in chimpanzee canines from the Fongoli site, Senegal (Skinner and Pruetz: Am J Phys Anthropol 149 (2012) 468-482). Based on an observation in a localized enamel fracture surface of a canine of a chimpanzee from the Taï Forest (Ivory Coast), these authors inferred that a nonemergence of striae of Retzius could be the cause for the "missing perikymata" phenomenon in the Fongoli chimpanzees. To check this inference, we analyzed the structure of outer enamel in three chimpanzee canines. The teeth were studied using light-microscopic and scanning-electron microscopic techniques. Our analysis of the specimen upon which Skinner and Pruetz (Am J Phys Anthropol 149 (2012) 468-482) had made their original observation does not support their hypothesis. We demonstrate that the enamel morphology described by them is not caused by a nonemergence of striae of Retzius ...
The relationships between age (range: 3 to 14 yr), mandibular bone fluoride level (marker of accu... more The relationships between age (range: 3 to 14 yr), mandibular bone fluoride level (marker of accumulated internal dose, range: 597 to 4680 mg F − kg −1 dry wt) and intensity of dental fluorosis (reflecting fluoride exposure during enamel formation) were studied in a sample of 53 fluorosed red deer from a fluoride-polluted area in the Czech-German border region (Ore mountains and their southern foreland). Assessment of the severity of dental fluorosis was performed for the 3 permanent premolars and 3 molars of one hemimandible per animal by using an ordinal measurement scale. For statistical analysis, the maximum tooth score of fluorosis (MTS) and the dental lesion index of fluorosis (DLI, sum of the six tooth scores per individual) were used. In the sample, both MTS (r s = 0.850) and DLI (r s = 0.813) were highly significantly (p <0.00001) correlated with bone fluoride content. A weaker correlation existed between age and bone fluoride content (r s = 0.322, p <0.05). The results demonstrate that in case of regional, long-term fluoride pollution, dental fluorosis (measured as MTS or DLI) can be used as a sensitive biomarker of fluoride exposure in deer and thus as an indicator of the level of environmental contamination by fluorides. In many countries, skulls and mandibles of wild deer are regularly and continuously collected by hunters. Assessment of the prevalence and severity of dental fluorosis in this material offers the opportunity for an efficient large-scale biomonitoring of environmental pollution by fluorides at very low cost.
only three males (two in period 1, one in period 4) stayed in the day roost all night. the other ... more only three males (two in period 1, one in period 4) stayed in the day roost all night. the other tracked animals left their day-roost for the first time between 25 and 220 minutes after sunset, and their last arrival at the day-roost occurred between 2 and 545 minutes before sunrise. Bats spent most of their nocturnal activity time foraging (overall mean: 79.7 % of nocturnal activity time). duration of nocturnal activity and nightly foraging time varied considerably over the four observation periods and were most extended in midsummer (period 3). this is a time of high spermatogenetic activity and steep increase in body mass (built-up of fat reserves), which leads to a particularly high food demand of male daubenton's bats during this period of the year. our results of an increased foraging activity during midsummer provide evidence in support of the view that food demand of male daubenton's bats is indeed highest during this time of the year.
ENCARNAÇÃO, J. A., U. KIERDORF, V. WOLTERS: Effects of age and season on body mass and reproducti... more ENCARNAÇÃO, J. A., U. KIERDORF, V. WOLTERS: Effects of age and season on body mass and reproductive condition in male Daubenton's bats (Myotis daubentonii). Vet. arhiv 76, S239-S249, 2006. ABSTRACT We analyzed the effects of age and season on body mass and reproductive condition in male Daubenton's bats (Myotis daubentonii) from a study area in central Germany, which were captured during April to October of the years 1998-2003. On first capture, animals (n=336) were banded and classified as either young of the year or adults (i.e. males ≥ 1 year of age). On recapture, animals first caught as young of the year could be assigned an exact age in years. Epididymal distension in young of the year indicated that some males had reached sexual maturity (defined as onset of spermatogenesis) already in their year of birth, while others did so in their second summer. Body mass and epididymal distension showed pronounced variation related to age and season, with highest values reached...
The periodic replacement of antlers is an exceptional regenerative process in mammals, which in g... more The periodic replacement of antlers is an exceptional regenerative process in mammals, which in general are unable to regenerate complete body appendages. Antler regeneration has traditionally been viewed as an epimorphic process closely resembling limb regeneration in urodele amphibians, and the terminology of the latter process has also been applied to antler regeneration. More recent studies, however, showed that, unlike urodele limb regeneration, antler regeneration does not involve cell dedifferentiation and the formation of a blastema from these dedifferentiated cells. Rather, these studies suggest that antler regeneration is a stemcell-based process that depends on the periodic activation of, presumably neural-crest-derived, periosteal stem cells of the distal pedicle. The evidence for this hypothesis is reviewed and as a result, a new concept of antler regeneration as a process of stem-cell-based epimorphic regeneration is proposed that does not involve cell dedifferentiation or transdifferentiation. Antler regeneration illustrates that extensive appendage regeneration in a postnatal mammal can be achieved by a developmental process that differs in several fundamental aspects from limb regeneration in urodeles.
We studied age-related variation in body mass and epididymal distension in male Daubenton's bats.... more We studied age-related variation in body mass and epididymal distension in male Daubenton's bats. Examination of data on epididymal distension in young of the year indicates that some reach sexual maturity by the year of birth, whereas others do so in their 2nd summer. Body mass and epididymal distension were positively correlated in young of the year and adults, suggesting that early sexual maturation and reproductive condition during later life are dependent on body condition. Older males tended to be heavier and in better reproductive condition than younger ones. Examination of our data suggests that physical and reproductive condition of males increase after the initial onset of fertility until 3 years of age. This late physical maturation is in line with other life-history traits characterizing long-lived bats as K-strategists among small mammals.
The study investigated developmental defects of the dental hard tissues and postmortem changes in... more The study investigated developmental defects of the dental hard tissues and postmortem changes in archaeological pig molars from Fais Island, Micronesia. The developmental defects of enamel were indicative of a disturbance of the secretory stage (accentuation of the incremental pattern, occurrence of Wilson bands and of hypoplastic defects) and the maturation stage of amelogenesis (hypomineralisation). Presence of coronal cementum in
Prevalence and intensity of enamel hypoplasia have been used as markers of generalized physiologi... more Prevalence and intensity of enamel hypoplasia have been used as markers of generalized physiological stress during dental development in a wide range of mammalian taxa. We studied cattle (Bos taurus) cheek teeth exhibiting morphological characteristics that are of relevance to the diagnosis of enamel hypoplasia in this and other bovid species. These characteristics were multiple, more or less horizontally arranged
Enamel is the most highly mineralized and durable tissue of the mammalian body. As enamel does no... more Enamel is the most highly mineralized and durable tissue of the mammalian body. As enamel does not undergo remodeling or repair, disturbances of enamel formation leave a permanent record in the tissue that can be used for life history reconstruction. This study reports light and scanning electron microscope findings on hypoplastic enamel defects, and on the chronology of crown growth in the molars of sheep and goats. A marked reduction of enamel extension rates in cervical compared with more cuspal crown portions of sheep and goat molars was recorded, with formation of the cervical 25% of the crown taking about the same time as that of the upper 75% of the crown. This explains the more frequent occurrence of enamel hypoplasia in cervical compared with upper and middle crown portions. Regarding the identification of hypoplastic enamel defects by external inspection, our results suggest a dependence on the type of defect and the associated presence of smaller or larger amounts of coronal cementum. Defects considered to reflect a slight to moderate impairment of secretory ameloblast function can normally be correctly diagnosed as they are not occluded by thick layers of cementum. In contrast, defects denoting a severe impairment of enamel matrix secretion can typically not be correctly identified because they are occluded by large amounts of cementum, so that neither depth nor extension of the defects can be assessed on external inspection. In these cases, microscopic analysis of tooth sections is required for a correct diagnosis of the hypoplastic enamel defects.
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