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Uwe Kierdorf - One of the best experts on this subject based on the ideXlab platform.
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multiple osteochondromas of the Antlers and cranium in a free ranging white tailed deer odocoileus virginianus
PLOS ONE, 2017Co-Authors: Uwe Kierdorf, Santiago Gomez, Karl V Miller, Stefan Flohr, Horst KierdorfAbstract:This paper reports a case of multiple osteochondromas affecting the Antlers and the left zygomatic bone of a free-ranging adult white-tailed buck (Odocoileus virginianus) from Georgia, USA. Along with a few postcranial bones, the antlered cranium of the individual was found in a severely weathered condition and devoid of any soft tissue. The Antlers exhibited five pedunculated exostoses that were composed of cancellous bone and, in their peripheral portions, also mineralized cartilage. The largest of the exostoses, located on the right antler, had a maximum circumference of 55 cm. The exostosis arising from the zygomatic bone was broad-based and much smaller than the exophytic outgrowths on the Antlers. Diagnosis of the exostoses as osteochondromas was based on their overall morphology, the normal bone structure in their stalk regions, and the continuity of their spongiosa and cortex with the respective components of the parent bones. Antleromas, i.e., pathological outgrowths developing on Antlers as a result of insufficient androgen production, were excluded in the differential diagnosis, based on (1) the apparent maturity and, except for the tumors, normal shape of the Antlers and (2) the fact that exostosis formation had also affected the zygomatic bone. Previously only a single case of solitary osteochondroma of an antler has been described in the scientific literature. The case presented here is the first report of multiple osteochondromas in a deer. As Antlers are regularly collected as trophies, and huge numbers of them are critically inspected each year, the fact that thus far only two cases of antler osteochondromas have been reported suggests that these tumors are very rare.
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labeling studies on cortical bone formation in the Antlers of red deer cervus elaphus
Bone, 2013Co-Authors: Santiago Gomez, Andrés J. Garcia, Laureano Gallego, Uwe Kierdorf, Horst Kierdorf, Tomas Landetecastillejos, Salvador LunaAbstract:The formation and mineralization process of Antlers, which constitute the fastest growing bones in vertebrates, is still not fully understood. We used oxytetracycline injections to label different stages of bone formation in Antlers of 14 red deer between days 28 and 156 of antler growth. Results show that initially a trabecular scaffold of woven bone is formed which largely replaces a pre-existing scaffold of mineralized cartilage. Lamellar bone is then deposited and from about day 70 onwards, primary osteons fill in the longitudinal tubes lined by the scaffold in a proximal to distal sequence. Mineral apposition rate (MAR) in early stages of primary osteon formation is very high (average 2.15 μm/d). Lower MARs were recorded for later stages of primary osteon formation (1.56 μm/d) and for the smaller secondary osteons (0.89 μm/d). Results suggest a peak in mineral demand around day 100 when the extent of mineralizing surfaces is maximal. A few secondary osteons were formed in a process of antler modeling rather than remodeling, as it occurred simultaneously with formation of primary osteons. The degree of cortical porosity reflects a reduction in MAR during later stages of osteonal growth, whereas cortical thickness is determined earlier. Injections given when the Antlers were largely or completely clean from velvet produced no labels in antler bone, strongly suggesting that Antlers are dead after velvet shedding. The rapidity of antler mineralization and the short lifespan of Antlers make them an extraordinary model to assess the effects of chemicals impairing or promoting bone mineralization.
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deer Antlers a model of mammalian appendage regeneration an extensive review
Gerontology, 2011Co-Authors: Uwe Kierdorf, Horst KierdorfAbstract:Background: Compared with other vertebrate taxa, mammals possess a very limited capacity for appendage regeneration. The Antlers of deer are an exception in that they are periodically lost and fully regenerated throughout the life of an individual. Objective: In this paper we compare certain aspects of antler regeneration with regenerative processes in other vertebrates. Methods: Review of the literature. Results: Recent studies suggest that antler regeneration is a stem cell-based process and that these stem cells are located in the pedicle periosteum. There is evidence that signaling pathways known to operate during appendage regeneration in other vertebrates are also activated during antler regeneration. There are, however, also differences between Antlers and other systems of epimorphic regeneration. Thus, contrary to amphibian limb regeneration, signaling from the wound epidermis appears not to be of crucial importance for antler regeneration. Healing of the casting wound typically involves no or only minor scarring, making Antlers interesting subjects for researchers attempting to reduce scar formation during wound healing in humans. The fact that despite their enormous growth rate the Antlers of intact and castrated deer appear to be resistant to malignant transformation furthermore offers research opportunities for cancer biology. Conclusions: Studying antler renewal as an example of mammalian appendage regeneration may provide crucial information for regenerative medicine to achieve its ultimate goal of stimulating limb regeneration in humans. A deeper understanding of the developmental mechanisms involved in antler renewal can also be useful for controlling induced regeneration processes in mammals.
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Antlers as biomonitors of environmental pollution by lead and fluoride: A review
European Journal of Wildlife Research, 2005Co-Authors: Uwe Kierdorf, Horst KierdorfAbstract:Antlers are periodically cast and re-grown cranial appendages of deer. Both endochondral and intramembranous ossification are involved in the formation of antler bone. After velvet shedding, Antlers are completely bony structures which are referred to as hard Antlers. Growing Antlers accumulate substances with an affinity to mineralized tissues. Among these substances are lead and fluoride. Due to the seasonally limited life span of Antlers, the concentrations of lead and fluoride in hard Antlers reflect uptake by the forming bone during a defined, species-specific period of some months. Antlers can thus be viewed as “naturally standardized” environmental samples that are well suited as biomonitors of environmental pollution by bone-seeking contaminants. Because hard Antlers are collected by hunters as trophies and kept in private or public collections, material for study can be obtained rather easily. So far, lead concentrations in hard Antlers have been reported only from Europe, whereas data for fluoride are available from both Europe and North America. Some studies compared contaminant concentrations in Antlers from different regions, while others analyzed time-trends in contaminant levels in Antlers from a single region. Using the latter approach, a pronounced drop of lead concentrations during recent decades has been reported for Antlers from various European countries. This indicates a marked decline of environmental lead levels that can be attributed mainly to the phase-out of leaded gasoline and, in addition, to a reduction of lead emissions also from stationary sources. In Germany, a corresponding drop has also been recorded for fluoride concentrations in Antlers, which is attributed to a decline of fluoride emissions from stationary sources due to improved emission-control measures. There is some evidence that exposure to higher levels of fluoride may lead to an impaired antler mineralization. Using Antlers as biomonitors has been shown to be an efficient method for assessing environmental pollution by lead and fluoride at low cost. Further studies using this now well established approach are therefore encouraged.
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histological structure of Antlers in castrated male fallow deer dama dama
Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology, 2004Co-Authors: Uwe Kierdorf, Horst Kierdorf, Michael Schultz, Hans J RolfAbstract:Antlers are periodically replaced cranial appendages that, except for the reindeer, are grown only by male deer. The annual antler cycle is controlled by seasonal fluctuations of sex steroid concentrations in the blood, and accordingly castration of male deer causes deviations from normal antler growth. The present study investigated antler histology of castrated fallow bucks (Dama dama). Castration in early spring was followed by casting of the hard Antlers carried by the bucks and the growth of a new set of Antlers, which remained in velvet permanently. In the following year, numerous bony protuberances developed from the original antler surface. Further growth of these protuberances, which were formed by subperiosteal intramembranous ossification, led to a marked increase in antler diameter in the affected areas. Compared to Antlers of intact bucks, the Antlers of the castrates showed histological signs of immaturity, suggestive of a reduced bone remodeling and an impairment of the mineralization process. These changes point to the dependence of the above processes on a stimulation by higher levels of sex steroids. Two years after castration, the Antlers also developed integumental thickening and showed an initial formation of skin outgrowths. Cystic structures were present in the skin, which were often filled with a presumably sebaceous and/or keratinous material. Formation of intradermal bone or cartilage was not observed in the Antlers of the castrated fallow bucks. The histological structure of the skin outgrowths suggested that they were caused by a hypertrophy of the dermal component of the velvet. Due to the localized bone overgrowth, resulting from the periosteal bone apposition onto the original antler surface, skin-lined infoldings originated, which reached deep into the newly formed bone. Our study revealed no indication of invasive/destructive bone growth in the Antlers, i.e., of a penetration of the newly formed bone tissue into the pre-existing bone. The hypertrophic bone growth in the Antlers of the castrates is compared with other forms of periosteally derived hypertrophic bone formation, including osteomas, in the mammalian skeleton. It is discussed whether the skin and bone outgrowths of the Antlers of castrated fallow bucks may be classified as benign tumors. © 2004 Wiley-Liss, Inc.
Laureano Gallego - One of the best experts on this subject based on the ideXlab platform.
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Effects of public vs. private management on deer antler composition, mechanical and structural variables
European Journal of Wildlife Research, 2013Co-Authors: Tomás Landete-castillejos, José A. Estevez, Francisco Ceacero, Andrés J. Garcia, Laureano GallegoAbstract:Previous studies have shown that antler mineral composition reflects diet. Thus, management involving diet can influence both the mineral composition and mechanical properties of Antlers. However, it is not known if reducing population density, which increases availability of food, can compensate mineral deficiencies arising from lack of minerals in plants and, ultimately, in the soil. The present study aimed at assessing if private management often involving a balanced food supplementation produced differences in antler properties compared to both public management and reference Antlers from deer farms. We also examined if low population density in a National Park could compensate for mineral deficiencies found in Antlers of other public reserves or else, Antlers still differed in antler characteristics compared to supplemented deer in private game estates. We used 120 Antlers from three public reserves, four private game estates and two deer farms as reference to assess antler composition, mechanical properties, size and structure. Public managed Antlers had shorter length compared to private and reference ones, thinner cortex (CT), were less dense, had lower second moment of area ( I ) and work to fracture ( W ). In addition, they had content in ash, Ca, Mg, Na, S and Zn lower than Antlers from private game estates. In contrast, Antlers from public reserves had greater values of Young’s modulus of elasticity ( E ), Fe, Mn and Si. In most cases, Antlers from private management and reference farms showed similar values. When comparing Antlers from low population density in a National Park with Antlers from private management, differences in antler length, CT, I and ash disappeared, but both differed still in density, E , bending strength, W and content in all minerals mentioned. In conclusion, low density can improve some structural variables, but it cannot compensate for mineral deficiencies whereas food supplementation can.
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labeling studies on cortical bone formation in the Antlers of red deer cervus elaphus
Bone, 2013Co-Authors: Santiago Gomez, Andrés J. Garcia, Laureano Gallego, Uwe Kierdorf, Horst Kierdorf, Tomas Landetecastillejos, Salvador LunaAbstract:The formation and mineralization process of Antlers, which constitute the fastest growing bones in vertebrates, is still not fully understood. We used oxytetracycline injections to label different stages of bone formation in Antlers of 14 red deer between days 28 and 156 of antler growth. Results show that initially a trabecular scaffold of woven bone is formed which largely replaces a pre-existing scaffold of mineralized cartilage. Lamellar bone is then deposited and from about day 70 onwards, primary osteons fill in the longitudinal tubes lined by the scaffold in a proximal to distal sequence. Mineral apposition rate (MAR) in early stages of primary osteon formation is very high (average 2.15 μm/d). Lower MARs were recorded for later stages of primary osteon formation (1.56 μm/d) and for the smaller secondary osteons (0.89 μm/d). Results suggest a peak in mineral demand around day 100 when the extent of mineralizing surfaces is maximal. A few secondary osteons were formed in a process of antler modeling rather than remodeling, as it occurred simultaneously with formation of primary osteons. The degree of cortical porosity reflects a reduction in MAR during later stages of osteonal growth, whereas cortical thickness is determined earlier. Injections given when the Antlers were largely or completely clean from velvet produced no labels in antler bone, strongly suggesting that Antlers are dead after velvet shedding. The rapidity of antler mineralization and the short lifespan of Antlers make them an extraordinary model to assess the effects of chemicals impairing or promoting bone mineralization.
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Factors affecting antler investment in Iberian red deer
Animal Production Science, 2012Co-Authors: José Gómez, Tomás Landete-castillejos, Francisco Ceacero, Andrés J. Garcia, E. Gaspar-lópez, Laureano GallegoAbstract:Antler constitutes such a costly trait that the skeleton of the deer undergoes a process similar to osteoporosis to meet the high demands of mineral deposition in the antler. The allometric relationship between antler and body size is one of the oldest known. However, no study has assessed the proportion that Antlers constitute with regard to the skeleton (from which most of the material is drawn), nor which factors influence this investment. To assess this, we studied 171 males (aged 1-5 years), determined their antler and bodyweights and scored their body condition. Then we calculated antler investment as antler weight relative to estimated skeletal weight. Results showed that antler investment in males 2 years old (i.e. excluding yearlings) depended on age rather than the whole bodyweight or body condition. Antler investment increased from 6% in yearlings to 35% in 5-year-old males, with a mean of 19%. A GLMM showed that in males 2 years old, within age, the heavier the male and the better the body condition at the start of antler growth, the greater the investment in Antlers. In yearlings, antler investment did not depend on bodyweight or body condition. In conclusion, antler weight relative to skeleton weight is a good method to assess antler investment. This investment is influenced by age and, in males 2 years old, also by bodyweight or condition at the start of antler growth.
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population management and bone structural effects in composition and radio opacity of iberian red deer cervus elaphus hispanicus Antlers
European Journal of Wildlife Research, 2008Co-Authors: Francisco Ceacero, Andrés J. Garcia, Tomas Landetecastillejos, J A Estevez, Laureano GallegoAbstract:Antlers are costly bone structures whose size and external characteristics are influenced by nutrition, climatic variability, and other factors. In this study, we examined the effects of a well-managed captive population vs unmanaged free-ranging herds (greatly differing in food availability and energetic and immunological expenditures) on antler structural characteristics of Iberian red deer. We assessed the effect of management and sample position in the antler on cortical bone depth, bone mineral and protein content, and radiographic bone opacity. Cortical bone depth and mineral percent was greater in captive animals on greater food availability and lower energetic and immunological expenditures. After removing the inverse relationship with mineral content in the model, protein percent was also higher in Antlers from captive than in those from free-ranging deer. Management system also influenced radio-opacity indirectly as interaction with other factors and cortical bone depth effects. Structural properties also differed between antler points that are very close in the antler and seem to differ only in the role they play. In conclusion, captive management can affect antler structure and composition, possibly as a result of different availability of food and immunological costs.
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baseline values for cast Antlers of iberian red deer cervus elaphus hispanicus
Zeitschrift Fur Jagdwissenschaft, 2002Co-Authors: Yolanda Fierro, Andrés J. Garcia, Christian Gortazar, Tomas Landetecastillejos, J Vicente, Laureano GallegoAbstract:Given that the introduction of allochthonous deer breeds in Spanish farms and hunting estates is becoming increasingly common, it is urgent to describe the morphology of Iberian red deer (Cervus elaphus hispanicus) Antlers. We use over 2,000 cast Antlers collected in Sierra Morena (southern Spain) to provide reference values for beam and first (brow) tine length, beam and burr circumference, and antler weight, depending on the number of antler points. In addition, this study includes a mean gross score of the trophy calculated according to the official formulae, as well as its correlation with the antler variables considered in this study. Beam length is the single most important factor for high score trophies, while factors such as antler weight or the number of antler points contribute little to the gross score. Management implications of these data are discussed.
Horst Kierdorf - One of the best experts on this subject based on the ideXlab platform.
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multiple osteochondromas of the Antlers and cranium in a free ranging white tailed deer odocoileus virginianus
PLOS ONE, 2017Co-Authors: Uwe Kierdorf, Santiago Gomez, Karl V Miller, Stefan Flohr, Horst KierdorfAbstract:This paper reports a case of multiple osteochondromas affecting the Antlers and the left zygomatic bone of a free-ranging adult white-tailed buck (Odocoileus virginianus) from Georgia, USA. Along with a few postcranial bones, the antlered cranium of the individual was found in a severely weathered condition and devoid of any soft tissue. The Antlers exhibited five pedunculated exostoses that were composed of cancellous bone and, in their peripheral portions, also mineralized cartilage. The largest of the exostoses, located on the right antler, had a maximum circumference of 55 cm. The exostosis arising from the zygomatic bone was broad-based and much smaller than the exophytic outgrowths on the Antlers. Diagnosis of the exostoses as osteochondromas was based on their overall morphology, the normal bone structure in their stalk regions, and the continuity of their spongiosa and cortex with the respective components of the parent bones. Antleromas, i.e., pathological outgrowths developing on Antlers as a result of insufficient androgen production, were excluded in the differential diagnosis, based on (1) the apparent maturity and, except for the tumors, normal shape of the Antlers and (2) the fact that exostosis formation had also affected the zygomatic bone. Previously only a single case of solitary osteochondroma of an antler has been described in the scientific literature. The case presented here is the first report of multiple osteochondromas in a deer. As Antlers are regularly collected as trophies, and huge numbers of them are critically inspected each year, the fact that thus far only two cases of antler osteochondromas have been reported suggests that these tumors are very rare.
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labeling studies on cortical bone formation in the Antlers of red deer cervus elaphus
Bone, 2013Co-Authors: Santiago Gomez, Andrés J. Garcia, Laureano Gallego, Uwe Kierdorf, Horst Kierdorf, Tomas Landetecastillejos, Salvador LunaAbstract:The formation and mineralization process of Antlers, which constitute the fastest growing bones in vertebrates, is still not fully understood. We used oxytetracycline injections to label different stages of bone formation in Antlers of 14 red deer between days 28 and 156 of antler growth. Results show that initially a trabecular scaffold of woven bone is formed which largely replaces a pre-existing scaffold of mineralized cartilage. Lamellar bone is then deposited and from about day 70 onwards, primary osteons fill in the longitudinal tubes lined by the scaffold in a proximal to distal sequence. Mineral apposition rate (MAR) in early stages of primary osteon formation is very high (average 2.15 μm/d). Lower MARs were recorded for later stages of primary osteon formation (1.56 μm/d) and for the smaller secondary osteons (0.89 μm/d). Results suggest a peak in mineral demand around day 100 when the extent of mineralizing surfaces is maximal. A few secondary osteons were formed in a process of antler modeling rather than remodeling, as it occurred simultaneously with formation of primary osteons. The degree of cortical porosity reflects a reduction in MAR during later stages of osteonal growth, whereas cortical thickness is determined earlier. Injections given when the Antlers were largely or completely clean from velvet produced no labels in antler bone, strongly suggesting that Antlers are dead after velvet shedding. The rapidity of antler mineralization and the short lifespan of Antlers make them an extraordinary model to assess the effects of chemicals impairing or promoting bone mineralization.
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deer Antlers a model of mammalian appendage regeneration an extensive review
Gerontology, 2011Co-Authors: Uwe Kierdorf, Horst KierdorfAbstract:Background: Compared with other vertebrate taxa, mammals possess a very limited capacity for appendage regeneration. The Antlers of deer are an exception in that they are periodically lost and fully regenerated throughout the life of an individual. Objective: In this paper we compare certain aspects of antler regeneration with regenerative processes in other vertebrates. Methods: Review of the literature. Results: Recent studies suggest that antler regeneration is a stem cell-based process and that these stem cells are located in the pedicle periosteum. There is evidence that signaling pathways known to operate during appendage regeneration in other vertebrates are also activated during antler regeneration. There are, however, also differences between Antlers and other systems of epimorphic regeneration. Thus, contrary to amphibian limb regeneration, signaling from the wound epidermis appears not to be of crucial importance for antler regeneration. Healing of the casting wound typically involves no or only minor scarring, making Antlers interesting subjects for researchers attempting to reduce scar formation during wound healing in humans. The fact that despite their enormous growth rate the Antlers of intact and castrated deer appear to be resistant to malignant transformation furthermore offers research opportunities for cancer biology. Conclusions: Studying antler renewal as an example of mammalian appendage regeneration may provide crucial information for regenerative medicine to achieve its ultimate goal of stimulating limb regeneration in humans. A deeper understanding of the developmental mechanisms involved in antler renewal can also be useful for controlling induced regeneration processes in mammals.
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Antlers as biomonitors of environmental pollution by lead and fluoride: A review
European Journal of Wildlife Research, 2005Co-Authors: Uwe Kierdorf, Horst KierdorfAbstract:Antlers are periodically cast and re-grown cranial appendages of deer. Both endochondral and intramembranous ossification are involved in the formation of antler bone. After velvet shedding, Antlers are completely bony structures which are referred to as hard Antlers. Growing Antlers accumulate substances with an affinity to mineralized tissues. Among these substances are lead and fluoride. Due to the seasonally limited life span of Antlers, the concentrations of lead and fluoride in hard Antlers reflect uptake by the forming bone during a defined, species-specific period of some months. Antlers can thus be viewed as “naturally standardized” environmental samples that are well suited as biomonitors of environmental pollution by bone-seeking contaminants. Because hard Antlers are collected by hunters as trophies and kept in private or public collections, material for study can be obtained rather easily. So far, lead concentrations in hard Antlers have been reported only from Europe, whereas data for fluoride are available from both Europe and North America. Some studies compared contaminant concentrations in Antlers from different regions, while others analyzed time-trends in contaminant levels in Antlers from a single region. Using the latter approach, a pronounced drop of lead concentrations during recent decades has been reported for Antlers from various European countries. This indicates a marked decline of environmental lead levels that can be attributed mainly to the phase-out of leaded gasoline and, in addition, to a reduction of lead emissions also from stationary sources. In Germany, a corresponding drop has also been recorded for fluoride concentrations in Antlers, which is attributed to a decline of fluoride emissions from stationary sources due to improved emission-control measures. There is some evidence that exposure to higher levels of fluoride may lead to an impaired antler mineralization. Using Antlers as biomonitors has been shown to be an efficient method for assessing environmental pollution by lead and fluoride at low cost. Further studies using this now well established approach are therefore encouraged.
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histological structure of Antlers in castrated male fallow deer dama dama
Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology, 2004Co-Authors: Uwe Kierdorf, Horst Kierdorf, Michael Schultz, Hans J RolfAbstract:Antlers are periodically replaced cranial appendages that, except for the reindeer, are grown only by male deer. The annual antler cycle is controlled by seasonal fluctuations of sex steroid concentrations in the blood, and accordingly castration of male deer causes deviations from normal antler growth. The present study investigated antler histology of castrated fallow bucks (Dama dama). Castration in early spring was followed by casting of the hard Antlers carried by the bucks and the growth of a new set of Antlers, which remained in velvet permanently. In the following year, numerous bony protuberances developed from the original antler surface. Further growth of these protuberances, which were formed by subperiosteal intramembranous ossification, led to a marked increase in antler diameter in the affected areas. Compared to Antlers of intact bucks, the Antlers of the castrates showed histological signs of immaturity, suggestive of a reduced bone remodeling and an impairment of the mineralization process. These changes point to the dependence of the above processes on a stimulation by higher levels of sex steroids. Two years after castration, the Antlers also developed integumental thickening and showed an initial formation of skin outgrowths. Cystic structures were present in the skin, which were often filled with a presumably sebaceous and/or keratinous material. Formation of intradermal bone or cartilage was not observed in the Antlers of the castrated fallow bucks. The histological structure of the skin outgrowths suggested that they were caused by a hypertrophy of the dermal component of the velvet. Due to the localized bone overgrowth, resulting from the periosteal bone apposition onto the original antler surface, skin-lined infoldings originated, which reached deep into the newly formed bone. Our study revealed no indication of invasive/destructive bone growth in the Antlers, i.e., of a penetration of the newly formed bone tissue into the pre-existing bone. The hypertrophic bone growth in the Antlers of the castrates is compared with other forms of periosteally derived hypertrophic bone formation, including osteomas, in the mammalian skeleton. It is discussed whether the skin and bone outgrowths of the Antlers of castrated fallow bucks may be classified as benign tumors. © 2004 Wiley-Liss, Inc.
Andrés J. Garcia - One of the best experts on this subject based on the ideXlab platform.
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Effects of public vs. private management on deer antler composition, mechanical and structural variables
European Journal of Wildlife Research, 2013Co-Authors: Tomás Landete-castillejos, José A. Estevez, Francisco Ceacero, Andrés J. Garcia, Laureano GallegoAbstract:Previous studies have shown that antler mineral composition reflects diet. Thus, management involving diet can influence both the mineral composition and mechanical properties of Antlers. However, it is not known if reducing population density, which increases availability of food, can compensate mineral deficiencies arising from lack of minerals in plants and, ultimately, in the soil. The present study aimed at assessing if private management often involving a balanced food supplementation produced differences in antler properties compared to both public management and reference Antlers from deer farms. We also examined if low population density in a National Park could compensate for mineral deficiencies found in Antlers of other public reserves or else, Antlers still differed in antler characteristics compared to supplemented deer in private game estates. We used 120 Antlers from three public reserves, four private game estates and two deer farms as reference to assess antler composition, mechanical properties, size and structure. Public managed Antlers had shorter length compared to private and reference ones, thinner cortex (CT), were less dense, had lower second moment of area ( I ) and work to fracture ( W ). In addition, they had content in ash, Ca, Mg, Na, S and Zn lower than Antlers from private game estates. In contrast, Antlers from public reserves had greater values of Young’s modulus of elasticity ( E ), Fe, Mn and Si. In most cases, Antlers from private management and reference farms showed similar values. When comparing Antlers from low population density in a National Park with Antlers from private management, differences in antler length, CT, I and ash disappeared, but both differed still in density, E , bending strength, W and content in all minerals mentioned. In conclusion, low density can improve some structural variables, but it cannot compensate for mineral deficiencies whereas food supplementation can.
-
labeling studies on cortical bone formation in the Antlers of red deer cervus elaphus
Bone, 2013Co-Authors: Santiago Gomez, Andrés J. Garcia, Laureano Gallego, Uwe Kierdorf, Horst Kierdorf, Tomas Landetecastillejos, Salvador LunaAbstract:The formation and mineralization process of Antlers, which constitute the fastest growing bones in vertebrates, is still not fully understood. We used oxytetracycline injections to label different stages of bone formation in Antlers of 14 red deer between days 28 and 156 of antler growth. Results show that initially a trabecular scaffold of woven bone is formed which largely replaces a pre-existing scaffold of mineralized cartilage. Lamellar bone is then deposited and from about day 70 onwards, primary osteons fill in the longitudinal tubes lined by the scaffold in a proximal to distal sequence. Mineral apposition rate (MAR) in early stages of primary osteon formation is very high (average 2.15 μm/d). Lower MARs were recorded for later stages of primary osteon formation (1.56 μm/d) and for the smaller secondary osteons (0.89 μm/d). Results suggest a peak in mineral demand around day 100 when the extent of mineralizing surfaces is maximal. A few secondary osteons were formed in a process of antler modeling rather than remodeling, as it occurred simultaneously with formation of primary osteons. The degree of cortical porosity reflects a reduction in MAR during later stages of osteonal growth, whereas cortical thickness is determined earlier. Injections given when the Antlers were largely or completely clean from velvet produced no labels in antler bone, strongly suggesting that Antlers are dead after velvet shedding. The rapidity of antler mineralization and the short lifespan of Antlers make them an extraordinary model to assess the effects of chemicals impairing or promoting bone mineralization.
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Factors affecting antler investment in Iberian red deer
Animal Production Science, 2012Co-Authors: José Gómez, Tomás Landete-castillejos, Francisco Ceacero, Andrés J. Garcia, E. Gaspar-lópez, Laureano GallegoAbstract:Antler constitutes such a costly trait that the skeleton of the deer undergoes a process similar to osteoporosis to meet the high demands of mineral deposition in the antler. The allometric relationship between antler and body size is one of the oldest known. However, no study has assessed the proportion that Antlers constitute with regard to the skeleton (from which most of the material is drawn), nor which factors influence this investment. To assess this, we studied 171 males (aged 1-5 years), determined their antler and bodyweights and scored their body condition. Then we calculated antler investment as antler weight relative to estimated skeletal weight. Results showed that antler investment in males 2 years old (i.e. excluding yearlings) depended on age rather than the whole bodyweight or body condition. Antler investment increased from 6% in yearlings to 35% in 5-year-old males, with a mean of 19%. A GLMM showed that in males 2 years old, within age, the heavier the male and the better the body condition at the start of antler growth, the greater the investment in Antlers. In yearlings, antler investment did not depend on bodyweight or body condition. In conclusion, antler weight relative to skeleton weight is a good method to assess antler investment. This investment is influenced by age and, in males 2 years old, also by bodyweight or condition at the start of antler growth.
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do drastic weather effects on diet influence changes in chemical composition mechanical properties and structure in deer Antlers
Bone, 2010Co-Authors: Francisco Ceacero, Andrés J. Garcia, Yolanda Fierro, Tomas Landetecastillejos, J A Estevez, J D Currey, A CalatayudAbstract:We attempted to determine why after an exceptionally hard winter deer Antlers fractured more often than usual. We assessed mechanical properties, structural variables and mineral composition of deer Antlers grown in a game estate (LM) after freezing temperatures (late winter frosts, LWF), which resulted in high incidence of antler fractures despite being grown later in the year, and those grown after a standard winter (SW). Within each year, specimens from broken and intact Antlers were assessed. LWF was associated with reduced impact energy (U) and somewhat reduced work to peak force (W), Young's modulus (E) and physical density, as well as cortical thickness. LWF was associated with considerably increased Si and reduced Na. In each year, broken Antlers had lower Mn, P and physical density, and they had more Na and B than unbroken Antlers. Because no such effect was found in farmed deer fed whole meal, and because freezing in plants usually produces an increase in Si content, which in turn reduces Mn, it is likely that LWF produced a diet rich in Si and low in Mn. Because Antlers are grown transferring calcium phosphate from the own skeleton and Ca/P levels were slightly reduced, it seems likely that Mn reduction may have increased antler fractures. A comparison between farm deer and those in another game estate (LI) also shows a link between lower Mn content and lower W. Thus, small changes in minor bone minerals, probably induced by diet, may have marked effects in mechanical properties of bone.
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population management and bone structural effects in composition and radio opacity of iberian red deer cervus elaphus hispanicus Antlers
European Journal of Wildlife Research, 2008Co-Authors: Francisco Ceacero, Andrés J. Garcia, Tomas Landetecastillejos, J A Estevez, Laureano GallegoAbstract:Antlers are costly bone structures whose size and external characteristics are influenced by nutrition, climatic variability, and other factors. In this study, we examined the effects of a well-managed captive population vs unmanaged free-ranging herds (greatly differing in food availability and energetic and immunological expenditures) on antler structural characteristics of Iberian red deer. We assessed the effect of management and sample position in the antler on cortical bone depth, bone mineral and protein content, and radiographic bone opacity. Cortical bone depth and mineral percent was greater in captive animals on greater food availability and lower energetic and immunological expenditures. After removing the inverse relationship with mineral content in the model, protein percent was also higher in Antlers from captive than in those from free-ranging deer. Management system also influenced radio-opacity indirectly as interaction with other factors and cortical bone depth effects. Structural properties also differed between antler points that are very close in the antler and seem to differ only in the role they play. In conclusion, captive management can affect antler structure and composition, possibly as a result of different availability of food and immunological costs.
Byoung Chul Park - One of the best experts on this subject based on the ideXlab platform.
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proteome analysis of red deer Antlers
Proteomics, 2004Co-Authors: Hee Jin Park, Sung Goo Park, Sang Chul Lee, Sayeon Cho, Ha Kun Kim, Jae Jong Kim, Hyunsu Bae, Do Hee Lee, Byoung Chul ParkAbstract:Deer Antlers are the only mammalian organs capable of repeated regeneration. Although Antlers are known to develop from pedicles, which arise from antlerogenic cells of cranial periosteum, their developmental process is not fully elucidated. For example, while endocrine and environmental factors influence the antler development, it is still unclear which signaling pathways are involved in the transduction of such stimuli. To study the developmental process of Antlers and identify proteins functioning in their growth, we have established proteome maps of red deer (Cervus elaphus) Antlers. With two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization mass spectrometry, we analyzed more than 800 protein spots and identified approximately 130 individual proteins derived from the growing tip of Antlers. The overall profile of the antler proteome was dissimilar to those of other types of tissue. Also comparison of proteomes derived from proximal bony tissue and the growing tip of Antlers revealed substantial differences. Moreover several cell growth or signaling-related proteins are expressed exclusively in the growing tip, suggesting that these proteins function in the growth and differentiation of Antlers. Currently, using the antler proteome maps, we are actively searching for the regulatory factor(s) that may control the antler development.
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Proteome analysis of red deer Antlers.
Proteomics, 2004Co-Authors: Hee Jin Park, Hee Lee, Sung Goo Park, Sang Chul Lee, Sayeon Cho, Ha Kun Kim, Jae Jong Kim, Hyunsu Bae, Byoung Chul ParkAbstract:Deer Antlers are the only mammalian organs capable of repeated regeneration. Although Antlers are known to develop from pedicles, which arise from antlerogenic cells of cranial periosteum, their developmental process is not fully elucidated. For example, while endocrine and environmental factors influence the antler development, it is still unclear which signaling pathways are involved in the transduction of such stimuli. To study the developmental process of Antlers and identify proteins functioning in their growth, we have established proteome maps of red deer (Cervus elaphus) Antlers. With two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization mass spectrometry, we analyzed more than 800 protein spots and identified ∼ 130 individual proteins derived from the growing tip of Antlers. The overall profile of the antler proteome was dissimilar to those of other types of tissue. Also comparison of proteomes derived from proximal bony tissue and the growing tip of Antlers revealed substantial differences. Moreover several cell growth or signaling-related proteins are expressed exclusively in the growing tip, suggesting that these proteins function in the growth and differentiation of Antlers. Currently, using the antler proteome maps, we are actively searching for the regulatory factor(s) that may control the antler development.