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1.
J Anat ; 243(5): 842-859, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37278321

RESUMO

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.


Assuntos
Chifres de Veado , Reabsorção Óssea , Cervos , Animais , Chifres de Veado/anatomia & histologia , Cervos/anatomia & histologia , Osso e Ossos , Minerais
2.
Mol Ecol ; 31(4): 1281-1298, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34878674

RESUMO

Sexually selected traits show large variation and rapid evolution across the animal kingdom, yet genetic variation often persists within populations despite apparent directional selection. A key step in solving this long-standing paradox is to determine the genetic architecture of sexually selected traits to understand evolutionary drivers and constraints at the genomic level. Antlers are a form of sexual weaponry in male red deer (Cervus elaphus). On the island of Rum, Scotland, males with larger antlers have increased breeding success, yet there has been no evidence of any response to selection at the genetic level. To try and understand the mechanisms underlying this observation, we investigate the genetic architecture of ten antler traits and their principal components using genomic data from >38,000 SNPs. We estimate the heritabilities and genetic correlations of the antler traits using a genomic relatedness approach. We then use genome-wide association and haplotype-based regional heritability to identify regions of the genome underlying antler morphology, and an empirical Bayes approach to estimate the underlying distributions of allele effect sizes. We show that antler morphology is highly repeatable over an individual's lifetime, heritable and has a polygenic architecture and that almost all antler traits are positively genetically correlated with some loci identified as having pleiotropic effects. Our findings suggest that a large mutational target and genetic covariances among antler traits, in part maintained by pleiotropy, are likely to contribute to the maintenance of genetic variation in antler morphology in this population.


Assuntos
Chifres de Veado , Cervos , Animais , Chifres de Veado/anatomia & histologia , Chifres de Veado/fisiologia , Teorema de Bayes , Cervos/genética , Estudo de Associação Genômica Ampla , Genômica , Masculino
3.
Cells ; 10(5)2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33947050

RESUMO

In polyandrous species, males face reproductive competition both before and after mating. Sexual selection thus shapes the evolution of both pre- and postcopulatory traits, creating competing demands on resource allocation to different reproductive episodes. Traits subject to strong selection exhibit accelerated rates of phenotypic divergence, and examining evolutionary rates may inform us about the relative importance and potential fitness consequences of investing in traits under either pre- or postcopulatory sexual selection. Here, we used a comparative approach to assess evolutionary rates of key competitive traits in two artiodactyl families, bovids (family Bovidae) and cervids (family Cervidae), where male-male competition can occur before and after mating. We quantified and compared evolutionary rates of male weaponry (horns and antlers), body size/mass, testes mass, and sperm morphometrics. We found that weapons evolve faster than sperm dimensions. In contrast, testes and body mass evolve at similar rates. These results suggest strong, but differential, selection on both pre- and postcopulatory traits in bovids and cervids. Furthermore, we documented distinct evolutionary rates among different sperm components, with sperm head and midpiece evolving faster than the flagellum. Finally, we demonstrate that, despite considerable differences in weapon development between bovids and cervids, the overall evolutionary patterns between these families were broadly consistent.


Assuntos
Evolução Molecular , Preferência de Acasalamento Animal , Ruminantes/genética , Animais , Chifres de Veado/anatomia & histologia , Tamanho Corporal , Masculino , Ruminantes/fisiologia , Espermatozoides/citologia , Testículo/anatomia & histologia
4.
PLoS One ; 15(11): e0239865, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33170859

RESUMO

The systematic use of antlers and other osseous materials by modern humans marks a set of cultural and technological innovations in the early Upper Paleolithic, as is seen most clearly in the Aurignacian. Split-based points, which are one of the most common osseous tools, are present throughout most regions where the Aurignacian is documented. Using results from recent and ongoing excavations at Geißenklösterle, Hohle Fels and Vogelherd, we nearly tripled the sample of split-based points from 31 to 87 specimens, and thereby enhance our understanding of the technological economy surrounding the production of osseous tools. Aurignacian people of the Swabian Jura typically left spit-based points at sites that appear to be base camps rich with numerous examples of personal ornaments, figurative art, symbolic imagery, and musical instruments. The artifact assemblages from SW Germany highlight a production sequence that resembles that of SW France and Cantabria, except for the absence of tongued pieces. Our study documents the life histories of osseous tools and demonstrates templates for manufacture, use, recycling, and discard of these archetypal artifacts from the Aurignacian. The study also underlines the diversified repertoire of modern humans in cultural and technological realms highlighting their adaptive capabilities.


Assuntos
Chifres de Veado/anatomia & histologia , Fósseis/anatomia & histologia , Atividades Humanas/história , Animais , Arqueologia , Características Culturais , Alemanha , História Antiga , Humanos
5.
Sci Rep ; 10(1): 8910, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32488122

RESUMO

Recent molecular phylogeny of deer revealed that the characters of antlers previously focused on are homoplasious, and antlers tend to be considered problematic for classification. However, we think antlers are important tools and reconsidered and analysed the characters and structures to use them for classification. This study developed a method to describe the branching structure of antlers by using antler grooves, which are formed on the antlers by growth, and then projecting the position of the branching directions of tines on the burr circumference. By making diagrams, comparing the branching structure interspecifically, homologous elements (tines, beams, and processes) of the antlers of 25 species of 16 genera were determined. Subsequently, ancestral state reconstruction was performed on the fixed molecular phylogenetic tree. It was revealed that Capreolinae and Cervini gained respective three-pointed antlers independently, and their subclades gained synapomorphous tines. We found new homologous and synapomorphous characters, as the antler of Eld's deer, which has been classified in Rucervus, is structurally close to that of Elaphurus rather than that of Rucervus, consistent with molecular phylogeny. The methods of this study will contribute to the understanding of the branching structure and phylogeny of fossil species and uncover the evolutionary history of Cervidae.


Assuntos
Chifres de Veado/anatomia & histologia , Evolução Biológica , Cervos/anatomia & histologia , Animais , Cervos/classificação , Cervos/genética , Masculino , Cervo Muntjac/anatomia & histologia , Cervo Muntjac/classificação , Cervo Muntjac/genética , Filogenia , Rena/anatomia & histologia , Rena/classificação , Rena/genética
6.
Biol Rev Camb Philos Soc ; 95(4): 986-1019, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32338826

RESUMO

This review describes the formation, structure, and function of bony compartments in antlers, horns, ossicones, osteoderm and the os penis/os clitoris (collectively referred to herein as AHOOO structures) in extant mammals. AHOOOs are extra-skeletal bones that originate from subcutaneous (dermal) tissues in a wide variety of mammals, and this review elaborates on the co-development of the bone and skin in these structures. During foetal stages, primordial cells for the bony compartments arise in subcutaneous tissues. The epithelial-mesenchymal transition is assumed to play a key role in the differentiation of bone, cartilage, skin and other tissues in AHOOO structures. AHOOO ossification takes place after skeletal bone formation, and may depend on sexual maturity. Skin keratinization occurs in tandem with ossification and may be under the control of androgens. Both endochondral and intramembranous ossification participate in bony compartment formation. There is variation in gradients of density in different AHOOO structures. These gradients, which vary according to function and species, primarily reduce mechanical stress. Anchorage of AHOOOs to their surrounding tissues fortifies these structures and is accomplished by bone-bone fusion and Sharpey fibres. The presence of the integument is essential for the protection and function of the bony compartments. Three major functions can be attributed to AHOOOs: mechanical, visual, and thermoregulatory. This review provides the first extensive comparative description of the skeletal and integumentary systems of AHOOOs in a variety of mammals.


Assuntos
Chifres de Veado/fisiologia , Cervos/anatomia & histologia , Cornos/fisiologia , Mamíferos/anatomia & histologia , Mamíferos/fisiologia , Ruminantes/anatomia & histologia , Animais , Chifres de Veado/anatomia & histologia , Chifres de Veado/crescimento & desenvolvimento , Tatus/anatomia & histologia , Tatus/crescimento & desenvolvimento , Osso e Ossos/embriologia , Clitóris/anatomia & histologia , Cervos/crescimento & desenvolvimento , Feminino , Girafas/anatomia & histologia , Girafas/crescimento & desenvolvimento , Cornos/anatomia & histologia , Cornos/crescimento & desenvolvimento , Masculino , Mamíferos/crescimento & desenvolvimento , Pênis/anatomia & histologia , Ruminantes/crescimento & desenvolvimento , Pele/embriologia , Pele/crescimento & desenvolvimento , Tela Subcutânea/anatomia & histologia , Tela Subcutânea/embriologia
7.
PLoS One ; 15(3): e0229339, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130253

RESUMO

The Kura-Araxes cultural tradition (ca. 3500-2200 BCE) was one of the most widespread archaeological horizons in Southwest Asian prehistory, spanning from the Caucasus to the southern Levant. Although several decades of research have considerably increased our knowledge about this Early Bronze Age tradition, the social and economic organization of its communities remains a matter of much debate. Interpretations of the organization of Kura-Araxes craft economies range from need-based household production to extra-household specialized production for exchange and elite consumption. This issue stems from the absence of a systematic approach to studying the spatial organization of craft production; that is the study of the spatial distribution of archaeological material across multiple contexts to reconstruct the location of various activities involved in craft production. Extensive evidence for craft production at Köhne Shahar (KSH)-one of the largest Kura-Araxes sites ever discovered-provides an opportunity for such a study. Faunal remains are among the most abundant types of remains recovered at KSH Phases IV and V (ca. 2800-2500 BCE), where bone and antler were cached and then shaped into tools that were used to manufacture other objects like beads. We use zooarchaeology to study the spatial distribution of worked and unworked animal remains to analyze the function of several structures and spaces in the craft production areas to ultimately gain better insight into the organization of labor and the social organization of the community. We identify evidence for two antler storage units, numerous waste dumps, and several workshops. Some workshops manufactured a similar range of small, possibly ornamental objects, while others specialized in the manufacture of certain goods, textiles, and objects made of animal horn. When combined with other lines of evidence, our observations point to a community-wide production economy with little direct evidence for a stratified social organization. We argue that the absence of a strict social hierarchy at KSH and across the Kura-Araxes world is not evidence of the absence of social complexity, but the presence of a horizontal or heterarchical social order.


Assuntos
Arqueologia , Análise Espacial , Animais , Chifres de Veado/anatomia & histologia , Irã (Geográfico)
8.
Dokl Biol Sci ; 487(1): 115-118, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31571079

RESUMO

The giant deer Arvernocerosverestchagini David, 1992, authochtonous species of the Early Pleistocene biota of North Black Sea coastal area, is discovered in Crimea. The giant deer was a member of fossil fauna of vertebrates from the Pleistocene deposits of Taurida karst cave. According to biochronological data, this fauna is dated to 1.8-1.5 Ma.


Assuntos
Cervos/anatomia & histologia , Fósseis/anatomia & histologia , Animais , Chifres de Veado/anatomia & histologia , Cavernas
9.
J Morphol ; 280(7): 1071-1090, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31095779

RESUMO

In Ruminantia, the lacrimal bone forms a considerable part of the facial skeleton, and the morphology of its facial facet is highly variable when compared to other mammals. In this study, we quantify the species-specific variability in size and shape of the lacrimal facial facet in species of Cervidae (deer) and relate it to systematics and various aspects of their ecology and behavior. We sampled 143 skull specimens from 10 genera; 12 Moschus and 3 Tragulus specimens were used as outgroups. We find that size and shape of the lacrimal facial facet allow differentiating most species analyzed here, except for Mazama gouazoubira and Capreolus capreolus. Size and shape of the lacrimal facial facet vary widely across Cervidae regardless of their systematic relationships, ecology or behavior. Thus, we could not detect a unique signature of adaptational criteria in lacrimal morphology. Our data indicate that the lacrimal facial facet scales allometrically with skull size, in particular, the lacrimojugal length scales positively and the lacrimomaxillar length scales negatively. However, correlation analyses did not reveal any differences in the integration of the lacrimal bone with any specific skull module in any of the species compared. Lastly, we could not ascertain any correlation between the size and position of the preorbital depression with the size and shape of the lacrimal facial facet. We conclude that the lacrimal facial facet is highly flexible and may rapidly adjust to its surrounding bones. Its allometric growth appears to be an example of exaptation: changes in size and shape in the context of the increase of the skull length provide lacrimal contacts, in particular, a lacrimojugal one, which may serve to reduce mechanical loads resulting from increasingly larger antlers in large cervids.


Assuntos
Cervos/anatomia & histologia , Face/anatomia & histologia , Pontos de Referência Anatômicos , Animais , Chifres de Veado/anatomia & histologia , Biodiversidade , Tamanho Corporal , Masculino , Análise de Componente Principal , Crânio/anatomia & histologia , Especificidade da Espécie
10.
PLoS One ; 14(2): e0212545, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30794631

RESUMO

Evaluation of harvest data remains one of the most important sources of information in the development of strategies to manage regional populations of white-tailed deer. While descriptive statistics and simple linear models are utilized extensively, the use of artificial neural networks for this type of data analyses is unexplored. Linear model was compared to Artificial Neural Networks (ANN) models with Levenberg-Marquardt (L-M), Bayesian Regularization (BR) and Scaled Conjugate Gradient (SCG) learning algorithms, to evaluate the relative accuracy in predicting antler beam diameter and length using age and dressed body weight in white-tailed deer. Data utilized for this study were obtained from male animals harvested by hunters between 1977-2009 at the Berry College Wildlife Management Area. Metrics for evaluating model performance indicated that linear and ANN models resulted in close match and good agreement between predicted and observed values and thus good performance for all models. However, metrics values of Mean Absolute Error and Root Mean Squared Error for linear model and the ANN-BR model indicated smaller error and lower deviation relative to the mean values of antler beam diameter and length in comparison to other ANN models, demonstrating better agreement of the predicted and observed values of antler beam diameter and length. ANN-SCG model resulted in the highest error within the models. Overall, metrics for evaluating model performance from the ANN model with BR learning algorithm and linear model indicated better agreement of the predicted and observed values of antler beam diameter and length. Results of this study suggest the use of ANN generated results that are comparable to Linear Models of harvest data to aid in the development of strategies to manage white-tailed deer.


Assuntos
Chifres de Veado , Bases de Dados Factuais , Cervos , Modelos Biológicos , Redes Neurais de Computação , Animais , Chifres de Veado/anatomia & histologia , Chifres de Veado/crescimento & desenvolvimento , Cervos/anatomia & histologia , Cervos/fisiologia , Masculino
11.
Nature ; 563(7732): S86-S88, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30464288
12.
J Anat ; 232(1): 72-79, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29023690

RESUMO

Horns are permanent structures projecting from the head of bovids, consisting of a bony horncore covered with a layer of skin and then a sheath of keratinous material showing variability of growth intensity based on nutrition. From the point of view of the horn's mechanical properties, the keratin sheath has been widely studied, but only a few studies have considered the complete structure of the horn and fewer studies have focused on the bony horncore and its characteristics. The latter showed the important role of the bony core, when cranial appendages are subject to mechanical stress (as happens during fighting). The mechanical properties of bone material, along with its mineral profile, are also important, because they can show effects of different factors, such as nutrition and mineral deficiencies in diet. For this reason, eight horncores of captive common eland male were sampled at four positions along the vertical axis of the horn. The main aim was to study variation in mechanical properties and the mineral content along the vertical axis of the horncores. We further analysed whether the spiral bony ridge present on eland horncores differs in any of the studied properties from adjacent parts of the horncore. In other antelopes, spiral ridges on the horns have been proposed to increase grip during wrestling between males. Cross-sections of the horncores were performed at four positions along the longitudinal axis and, for each position, two bone bars were extracted to be tested in impact and bending. Moreover, in the first sampling position (the closest position to the base) two bars were extracted from the spiralled bony area. The resulting fragments were used to measure ash content, bone density and mineral content. Results showed that horn bone decreased along the vertical axis, in ash (-36%), density (-32%), and in impact work 'U' (marginally significant but large effect: -48%). The concentration of several minerals decreased significantly (Mg, Cr, Mn and Tl by -33%, -25%, -31%, -43%, respectively) between the basal and the uppermost sampling site. The bone tissue of the horncore spiral compared with non-spiral bone of the same position showed a lower ash content (53% vs. 57%), Mg and Mn; in addition to showing approximately half values in work to peak force 'W', bending strength 'BS' and 'U', but not in Young's modulus of elasticity 'E'. In conclusion, similarly to the results in a totally different fighting bony structure, the antlers, the horncore of eland shows advantageous parameters in bone tissue of the base in respect to the tip, with higher values for mechanical properties, density and mineral profile. Moreover, the spiral bone tissue showed lower material mechanical properties. Probably the spiral tissue of the horn may have a role in deflecting potential cross-sectional fractures during wrestling. In addition, it may serve to improve the grip during wrestling, and we propose that it may also prevent risk of rotation of sheath with respect to internal bone not only in this, but also in other straight bovid horns.


Assuntos
Chifres de Veado/anatomia & histologia , Chifres de Veado/fisiologia , Animais , Chifres de Veado/química , Bovinos , Estresse Mecânico
13.
J Vis Exp ; (126)2017 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-28809837

RESUMO

Cervid phenotype can be placed into one of two categories: efficiency, which promotes survival over extravagant morphometric growth, and luxury, which promotes growth of large weaponry and body size. Populations of the same species display each phenotype depending on environmental conditions. Although antler and body size of male white-tailed deer (Odocoileus virginianus) varies by physiographic region in Mississippi, USA and is strongly correlated with regional variation in nutritional quality, the effects of population-level genetics from native stocks and previous re-stocking efforts cannot be disregarded. This protocol describes how we designed a controlled study, where other factors that influence phenotype, such as age and nutrition, are controlled. We brought wild-caught pregnant females and six-month-old fawns from three distinct physiographic regions in Mississippi, USA to the Mississippi State University Rusty Dawkins Memorial Deer Unit. Deer from the same region were bred to produce a second generation of offspring, allowing us to assess generational responses and maternal effects. All deer ate the same high-quality (20% crude protein deer pellet) diet ad libitum. We uniquely marked each neonate and recorded body mass, hind foot, and total body length. Each subsequent fall, we sedated individuals via remote injection and sampled the same morphometrics plus antlers of adults. We found that all morphometrics increased in size from first to second generation, with full compensation of antler size (regional variation no longer present) and partial compensation of body mass (some evidence of regional variation) evident in the second generation. Second generation males that originated from our poorest quality soil region displayed about a 40% increase in antler size and about a 25% increase in body mass when compared to their wild harvested counterparts. Our results suggest phenotypic variation of wild male white-tailed deer in Mississippi are more related to differences in nutritional quality than population-level genetics.


Assuntos
Chifres de Veado/crescimento & desenvolvimento , Cervos/crescimento & desenvolvimento , Cervos/genética , Fenômenos Fisiológicos da Nutrição Animal , Animais , Chifres de Veado/anatomia & histologia , Tamanho Corporal/genética , Dieta , Ecossistema , Feminino , Masculino , Mississippi , Fenótipo , Solo , Telemetria/instrumentação , Telemetria/métodos
14.
Front Biosci (Landmark Ed) ; 22(10): 1622-1633, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28410135

RESUMO

Deer antlers can be developed into multiple novel models to study growth and development of tissues for biomedical research. To facilitate this process, we have invented and further refined five custom-built tools through three decades of antler research. These are: 1. Pedicle growth detector to pinpoint the timing when pedicle growth is initiated, thus stimuli for pedicle and first antler formation can be investigated and identified. 2. Thin periosteum slice cutter to thinly slice (0.2mm or 0.7 mm thick) a whole piece of antlerogenic periosteum (AP) or pedicle periosteum (PP), which facilitates gene delivery into cells resident in these tissues, thus making transgenic antlers possible. 3. The porous periosteum multi-needle punch to effectively loosen the dense AP or PP tissue. This allows most cells of the periosteum to come into direct contact with treating solutions, thus making artificial manipulation of antler development possible. 4. The intra-dermal pocket maker to cut the thin dermal tissue (less than 2 mm in thickness) of a male deer calf horizontally into two layers to make an intra-dermal pocket. This allows loading of AP tissue intra-dermally to test the theory of "antler stem cell niche" in vivo. 5. The sterile periosteum sampling system to allow aseptic collection of the AP, PP or the antler growth centre tissue on farm, thus allowing antler generation, regeneration or rapid growth to be investigated in vitro. Overall, we believe the application of contemporary cellular and molecular biological techniques coupled with these custom-built tools would greatly promote the establishment of this unique and novel model for the benefits of biomedical research, and hence human health.


Assuntos
Chifres de Veado/fisiologia , Cervos/fisiologia , Periósteo/fisiologia , Regeneração , Manejo de Espécimes/instrumentação , Manejo de Espécimes/métodos , Animais , Chifres de Veado/anatomia & histologia , Cervos/anatomia & histologia , Dissecação/instrumentação , Dissecação/métodos , Masculino , Microtomia/instrumentação , Microtomia/métodos , Modelos Animais , Periósteo/anatomia & histologia , Medicina Regenerativa/instrumentação , Medicina Regenerativa/métodos , Medicina Regenerativa/tendências , Pesquisa/tendências
15.
Animal ; 11(8): 1312-1320, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28069103

RESUMO

The main factors affecting the mechanical (and other) properties of bone, including antler, are the proportions of ash (especially Ca and P) and collagen content. However, some trace minerals may also play more important roles than would be expected, given their low levels in bone and antler. One such trace mineral is Cu. Here, we studied the effects of Cu supplementation on the mechanical and structural characteristics, and mineral content of antlers from yearling and adult (4 years of age) red deer fed a balanced diet. Deer (n=35) of different ages (21 yearlings and 14 adults) were studied. A total of 18 stags (11 yearlings and 7 adults) were injected with Cu (0.83 mg Cu/kg BW) every 42 days, whereas the remaining 17 (10 yearlings and 7 adults) were injected with physiological saline solution (control group). The Cu content of serum was analysed at the beginning of the trial and 84 days after the first injection to assess whether the injected Cu was mobilized in blood. Also, the mechanical and structural properties of antlers and the mineral content in their cortical walls were examined at three (yearlings) or four (adults) points along the antler beam. The effect of Cu supplementation was different in yearlings and adults. In yearlings, supplementation increased the Cu content of serum by 28%, but did not affect antler properties. However, in adults, Cu supplementation increased the Cu content of serum by 38% and tended to increase the cortical thickness of antlers (P=0.06). Therefore, we conclude that, even in animals receiving balanced diets, supplementation with Cu could increase antler cortical thickness in adult deer, although not in yearlings. This may improve the trophy value of antlers, as well as having potential implications for bones in elderly humans, should Cu supplementation have similar effects on bones as those observed in antlers.


Assuntos
Cobre/administração & dosagem , Cervos/anatomia & histologia , Suplementos Nutricionais , Minerais/análise , Animais , Chifres de Veado/anatomia & histologia , Chifres de Veado/química , Chifres de Veado/efeitos dos fármacos , Osso e Ossos/anatomia & histologia , Osso e Ossos/química , Osso e Ossos/efeitos dos fármacos , Cálcio/análise , Colágeno/análise , Masculino , Fósforo/análise
16.
J Morphol ; 278(2): 182-202, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27859491

RESUMO

Antlers are unique appendages. They are shed and rebuilt at intervals, and are synapomorphic for all living Cervidae (except for the Chinese water deer, Hydropotes inermis, in which they have presumably been lost). The antlerogenic process is controlled by a complex interaction of fluctuating levels of several hormones, most importantly testosterone. The oldest antler remains are recorded from the early Miocene; these have been interpreted as non-deciduous appendages because of supposed permanent skin coverage and the lack of a burr (a well-developed osseous protuberance around the base of the antler, which is always present in extant cervids). The aim of this study is to test the hypothesis that antler shedding was possible in these early Miocene cervids. Antlers of all extant and eight Miocene cervid genera, including burr-less antler fragments of the earliest cervids Procervulus, Ligeromeryx, and Lagomeryx were studied. An extensive comparative morphological analysis of external features of the antler, and of the abscission area and the base of the antler in particular, was undertaken. The results indicate that a regular, porous, and rugose abscission surface at the proximal end of the antler indicates antler shedding in both living and fossil cervids. The antler shedding mechanism must therefore have already been present in all early/mid Miocene cervid genera included in this study. On this basis, it is suggested that the presence of a burr is not prerequisite in order to shed antlers, that the presence of perpetual antlers has not yet been verified, and that the process of shedding and regeneration developed with the first appearance of these organs. This insight is particularly important for the systematic classification of early Miocene species as Cervidae, because the absence of the antler shedding and rebuilding mechanism would exclude them from the taxon Cervidae and from any relationship with extant cervids. J. Morphol. 278:182-202, 2017. © 2016 Wiley Periodicals,Inc.


Assuntos
Chifres de Veado/anatomia & histologia , Chifres de Veado/fisiologia , Cervos/anatomia & histologia , Cervos/fisiologia , Regeneração/fisiologia , Animais , Masculino
17.
Folia Morphol (Warsz) ; 76(2): 269-276, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27813624

RESUMO

BACKGROUND: Antlers are lined by soft velvet tissue during antler growth. Later, the velvet is shed before rut onset. There are no detailed histological descriptions of the growing velvet, nor whether the velvet changes according to stag age. Our aims were to: 1) describe the basic histology of pampas deer antler velvet from adult and yearling males; and 2) determine the influence of age and time of antler growth on velvet's tissues morphometry. MATERIALS AND METHODS: Samples were collected from 10 stags allocated in two groups, either adult (3-5 years old, n = 5) or yearling males (2 years old, n = 5). The day of antler cast was recorded for each animal. In spring, the stags were anaesthetised and velvet samples were collected from the third tine's distal end. Samples were described qualitatively and a restricted morphometrical analysis of the antler velvet was performed. RESULTS: The number of keratinocyte layers and the thicknesses of: total epidermis, corneum, intermediate and basale epidermal strata, total dermis, superficial and deep dermis were determined. Age and days after antler casting positively influenced in conjunction epidermal thickness (p = 0.037), and tended to influence both stratum intermedium (p = 0.076) and stratum corneum (p = 0.1) thicknesses. Age influenced stratum corneum thickness (p = 0.04). The pampas deer antler velvet lacked both sweat glands and arrector pili muscles. CONCLUSIONS: The deep dermis was densely irrigated but displayed abundant and well developed collagen bundles. Both total epidermal and stratum corneum thicknesses related positively to the age of the animals but were not to the time since antler cast.


Assuntos
Envelhecimento/fisiologia , Chifres de Veado/anatomia & histologia , Chifres de Veado/citologia , Cervos/anatomia & histologia , Animais , Derme/citologia , Epiderme/anatomia & histologia
18.
Vet Res Commun ; 40(3-4): 141-147, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27618827

RESUMO

There is a resurgence of interest in the study of deer antlers. Recent research advocates their potential for use in bone xenografts. Using this working hypothesis, we can formulate many questions: do antlers really present unique or interesting mechanical properties, and if so, which factors affect these properties? Many other issues, including tissue compatibility, could be discussed; however, this article will focus on the biomechanical features of antlers. This paper reviews some answers found within current published material, and could help determine the optimal selection of some antlers for further experimental studies and clinical trials. Some general elements like anatomy and histology of deer antlers are briefly summarised. This paper will attempt to define the fundamental differences between skeletal bone and antler bone in terms of their organic and mechanical properties. We will then compare the previously published data, which details the mechanical properties of antlers from different species of Cervidae, by reviewing several aspects such as: sex; geographical situation; morphology; hydration state; and mineral composition. Some findings emerge: mechanical properties do not vary with gender or latitude, and the most important determining factor appears to be the species, alongside morphology and use of antlers. The state of hydration and mineral composition also has an influence on the mechanical properties of Cervidae antlers.


Assuntos
Chifres de Veado/anatomia & histologia , Fenômenos Biomecânicos , Cervos/anatomia & histologia , Animais , Osso e Ossos/anatomia & histologia , Cervos/fisiologia
19.
J Evol Biol ; 29(3): 617-32, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26687843

RESUMO

The Hamilton-Zuk hypothesis proposes that the genetic benefits of preferences for elaborated secondary sexual traits have their origins in the arms race between hosts and parasites, which maintains genetic variance in parasite resistance. Infection, in turn, can be reflected in the expression of costly sexual ornaments. However, the link between immune genes, infection and the expression of secondary sexual traits has rarely been investigated. Here, we explored whether the presence and identity of functional variants (supertypes) of the highly polymorphic major histocompatibility complex (MHC), which is responsible for the recognition of parasites, predict the load of lung and gut parasites and antler development in the red deer (Cervus elaphus). While we found MHC supertypes to be associated with infection by a number of parasite species, including debilitating lung nematodes, we did not find support for the Hamilton-Zuk hypothesis. On the contrary, we found that lung nematode load was positively associated with antler development. We also found that the supertypes that were associated with resistance to certain parasites at the same time cause susceptibility to others. Such trade-offs may undermine the potential genetic benefits of mate choice for resistant partners.


Assuntos
Chifres de Veado/crescimento & desenvolvimento , Cervos/genética , Cervos/parasitologia , Complexo Principal de Histocompatibilidade/genética , Animais , Chifres de Veado/anatomia & histologia , Tamanho Corporal/genética , Variação Genética , Interações Hospedeiro-Parasita/genética , Pulmão/parasitologia , Masculino , Polônia , Seleção Genética
20.
Anim Sci J ; 87(8): 989-96, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26608104

RESUMO

For this study, we aimed to assess the dose-response antiosteoporotic effects of the middle section of velvet antlers (VAs) from sika deers (Cervus nippon) fed with different types of fodders. VAs prepared from farmed sika deers fed with feed mixtures containing sorghum distillery residue (VA-SDR) or without SDR (SDR replaced with hay, VA-Hay) were divided into upper (VAU), middle (VAM) and basal (VAB) sections. The chemical constituents of the middle sections obtained from each VA type were compared, and their antiosteoporotic activities were evaluated using rats with ovaries removed surgically (ovariectomy, OVX). The VA-Hay exhibited markedly increased iron and cysteine levels, whereas the VA-SDR exhibited markedly increased level of alcoholic extract and testosterone. Both VA-Hay- and VA-SDR-treated rats exhibited increased femur strength compared with the control group. However, VA-SDR exhibited greater bone-strengthening effects than did VA-Hay. The serum osteocalcin and estradiol levels were significantly moderated in the VA-Hay group alone. These results suggest that VA-SDR and VA-Hay prevent the loss of bone strength, and preserve trabecular architecture connectivity in an estrogen-deficient state. However, differences in the chemical compositions of different forages may be responsible for the varying antiosteoporotic mechanisms observed. Thus, the addition of SDR in deer forage may enhance antiosteoporosis activity in VAs, and confer considerable economic and ecological benefits.


Assuntos
Ração Animal/classificação , Chifres de Veado/anatomia & histologia , Chifres de Veado/química , Conservadores da Densidade Óssea , Cervos , Osteoporose Pós-Menopausa/tratamento farmacológico , Extratos de Tecidos/isolamento & purificação , Extratos de Tecidos/farmacologia , Ração Animal/análise , Animais , Força Compressiva/efeitos dos fármacos , Cisteína/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Estradiol/sangue , Feminino , Fêmur/fisiologia , Humanos , Ferro/metabolismo , Osteocalcina/sangue , Osteoporose Pós-Menopausa/metabolismo , Ratos , Ratos Sprague-Dawley , Testosterona/metabolismo
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