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1.
PLoS One ; 16(1): e0244661, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33513144

RESUMO

Amphimoschus is an extinct Eurasian ruminant genus, mostly recorded in Europe, without a close living relative and, hence, an unknown systematic position. This genus is known from around 50 localities from the late early to the middle Miocene. Two species were described during 180 years, but since their first description during the late 19th century and early 20th century, hardly any detailed taxonomic work has been done on the genus. Over the years, extensive collecting and excavating activities have enriched collections with more and more complete material of this still rare and enigmatic animal. Most interestingly, a number of skull remains have been unearthed and are promising in terms of providing phylogenetic information. In the present paper, we describe cranial material, the bony labyrinth, the dentition through 780 teeth and five skulls from different ontogenetic stages. We cannot find a clear morphometric distinction between the supposedly smaller and older species Amphimoschus artenensis and the supposedly younger and larger species A. ponteleviensis. Accordingly, we have no reason to retain the two species and propose, following the principle of priority (ICZN chapter 6 article 23), that only A. ponteleviensis Bourgeois, 1873 is valid. Our studies on the ontogenetic variation of Amphimoschus does reveal that the sagittal crest may increase in size and a supraorbital ridge may appear with age. Despite the abundant material, the family affiliation is still uncertain.


Assuntos
Artiodáctilos/anatomia & histologia , Fósseis/anatomia & histologia , Ruminantes/anatomia & histologia , Animais , Artiodáctilos/genética , Evolução Biológica , Dentição , Orelha Interna/anatomia & histologia , Orelha Interna/metabolismo , Europa (Continente) , Filogenia , Ruminantes/genética , Crânio/anatomia & histologia , Crânio/metabolismo
2.
Vet Clin North Am Food Anim Pract ; 37(1): 75-92, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33358313

RESUMO

Ultrasound imaging is the mainstay of urinary and reproductive imaging in small ruminants, assisted by the relatively superficial location of the urinary and reproductive tracts in these species. Radiography can provide an excellent overview of the abdomen, but is often limited by a lack of adequate penetration. Computed tomography scans provide summation-free imaging of the urinary and reproductive tracts in addition to information about the excretion of contrast agent by the kidneys, but can be limited by availability and cost.


Assuntos
Genitália/diagnóstico por imagem , Cabras/anatomia & histologia , Ovinos/anatomia & histologia , Sistema Urinário/diagnóstico por imagem , Animais , Feminino , Doenças das Cabras/diagnóstico por imagem , Masculino , Testes Imediatos , Reprodução , Ruminantes/anatomia & histologia , Doenças dos Ovinos/diagnóstico por imagem , Tomografia Computadorizada por Raios X/veterinária , Ultrassonografia/veterinária
3.
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
4.
Vet Ophthalmol ; 23(3): 472-479, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32012413

RESUMO

PURPOSE: To investigate the relationship between phylogeny and amount of shade in a species' habitat regarding the presence or absence of an iridal granula iridica (GI) in a large sample of Artiodactyl and Perissodactyl clades and using online resources. METHODS: The Comparative Ocular Pathology Laboratory of Wisconsin (COPLOW) archives were searched for glass slide material from Artiodactyl (even-toed) and Perissodactyl (odd-toed) ungulates. The slides were examined, and the presence or absence of the GI was noted. The phylogenetic tree of the ungulate species was inferred using TimeTree (http://www.timetree.org), and the habitat data are derived from Animal Diversity Web (https://animaldiversity.org/). We assessed the probability of the presence of GI occurring given the amount of shade in a species' environment using phylogenetic logistic regression. RESULTS: Forty-eight artiodactyl species were able to be evaluated and tabulated. Nine perissodactyl species were able to be evaluated. The phylogenetic logistic regression showed that the probability of GI presence was lower in artiodactyl species that inhabited shaded environments (ßshaded  = -1.774). Arctiodacyl species inhabiting a nonshaded environment were slightly more probable to have the GI present (ßnonshaded  = 0.023), with species inhabitating ambiguously shaded environments having a high probability of GI presence (ßambiguous  = 2.214). CONCLUSIONS: Our results suggest that the GI may be a common morphological feature to shade the pupil in nonshaded environments, and, in its absence, increase the amount of light reaching the retina to improve vision in shaded environments for hooved mammals. Further research on the functional optics of the GI and studies that include additional ungulate species would further elucidate phylogenetic and ecological factors influencing the occurrence of GI in hooved mammals.


Assuntos
Iris/anatomia & histologia , Ruminantes/anatomia & histologia , Animais , Ecossistema , Filogenia , Ruminantes/classificação , Ruminantes/fisiologia , Especificidade da Espécie
5.
J Hum Evol ; 140: 102383, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-28992952

RESUMO

We update here our recent revision of the Kanapoi ruminants and describe recently collected material. We now regard the occurrence of reduncins as doubtful, we revise the identification of a large raphicerin as being more probably Gazella, and we add Gazella cf. janenschi and the Cephalophini to the faunal list. New material of Tragelaphus kyaloi suggests that this species held its head unlike other tragelaphins, and was not an exclusive dedicated browser, but Kanapoi pre-dates the Pliocene change of Sivatherium, Aepyceros, Alcelaphini, and even Tragelaphini toward more grazing diets. Kanapoi shares several ruminant taxa with sites in Ethiopia and Tanzania, attesting to latitudinal exchanges.


Assuntos
Dieta/veterinária , Fósseis/anatomia & histologia , Ruminantes/classificação , Animais , Biota , Feminino , Girafas/anatomia & histologia , Girafas/classificação , Quênia , Masculino , Ruminantes/anatomia & histologia
6.
Histol Histopathol ; 35(2): 185-202, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31271442

RESUMO

The accessory organs of the eye represent part of the protective system of the eyeball. In the present study, an examination of the accessory organs of the eye of three species of captive ruminants was performed using light microscopy. In the okapi, the superficial gland of the third eyelid and lacrimal gland were complex branched multilobar tubular glands formed by mucous units with tubular secretory portions and no plasma cells. The deep gland of the third eyelid was absent in the okapi and present in both the Père David's deer and the Philippine mouse-deer. In the Philippine mouse-deer, the deep gland had a very thick connective capsule and thick interlobar septae. It contained fewer lobes forming the gland parenchyma compared to Père David's deer and other ruminants. Organized lymphoid follicles were present within the upper and lower eyelids only in the okapi and Père David's deer, while diffuse lymphocytes were observed in the Philippine mouse-deer. The orbital glands in the Père David's deer had a multilobar tubuloacinar structure with numerous plasma cells and a mucoserous character. In contrast to the Philippine mouse-deer, these glands had a serous character. The presence of several macroscopic and microscopic structural differences of the examined accessory organs of the eye in the three captive ruminant species may be understood within an ecological context and may be associated with different habitat-specific environmental conditions.


Assuntos
Cervos/anatomia & histologia , Pálpebras/anatomia & histologia , Girafas/anatomia & histologia , Aparelho Lacrimal/anatomia & histologia , Ruminantes/anatomia & histologia , Animais
7.
Proc Biol Sci ; 286(1915): 20192199, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31718495

RESUMO

Cranial weapons of all shapes and sizes are common throughout the animal kingdom and are frequently accompanied by the evolution of additional traits that enhance the use of those weapons. Bovids (cattle, sheep, goats, antelope) and cervids (deer) within the mammal clade Ruminantia are particularly well known for their distinct and varied cranial appendages in the form of horns and antlers, which are used as weapons in intraspecific combat between males for access to mates. Combat in these species takes many forms, including head-on collisions (ramming); stabbing an opponent's head or body with horn tips (stabbing); rearing and clashing downwards with horns (fencing); or interlocking antlers or horns while vigorously pushing and twisting (wrestling). Some aspects of weapon and skull morphology have been linked to combat behaviours in bovid and cervid species, but the contribution of postcranial structures that support these weapons, such as the neck, has not been explored. To investigate the role of the neck in intraspecific combat, we quantified biomechanically relevant linear variables of the cervical vertebrae (C1-C7) from males and females of 55 ruminant species. We then used phylogenetic generalized least-squares regression to assess differences among species that display primarily ramming, stabbing, fencing and wrestling combat styles. In males, we found that wrestlers have longer vertebral centra and longer neural spines than rammers, stabbers or fencers, while rammers have shorter and wider centra and taller neural spine lever arms. These results suggest a supportive role for the cervical vertebrae in resisting forces generated by male-male combat in ruminant mammals and indicate that evolutionary forces influencing cranial weapons also play a role in shaping the supporting anatomical structures.


Assuntos
Agressão , Vértebras Cervicais/anatomia & histologia , Ruminantes/anatomia & histologia , Animais , Fenômenos Biomecânicos , Feminino , Masculino , Ruminantes/fisiologia
8.
Okajimas Folia Anat Jpn ; 96(1): 27-30, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31462622

RESUMO

We examined the dorsal lingual surfaces of an adult bharal (Pseudois nayaur) by scanning electron microscopy. The filiform papillae of the lingual apex and body consisted of a main papilla and smaller secondary papillae. The filiform papilla of the lingual body was big as compared to that of the lingual apex. The connective tissue cores of the filiform papillae consisted of several processes. The fungiform papilla was round in shape. The connective tissue cores of the fungiform papillae were flower-bud shaped. The lenticular papillae of large size were limited on the lingual prominence. The connective tissue cores of the lenticular papillae were hair-like in shape. The vallate papillae were located on both sides of the posterolateral aspects. The vallate papillae were flattened-oval shaped and the papillae were surrounded by an oval-shaped trench. The connective tissue cores of the vallate papillae were covered with numerous small spines The lingual surface of the bharal closely resembled that of the family Bovidae.


Assuntos
Ruminantes/anatomia & histologia , Animais
9.
J Morphol ; 280(9): 1254-1266, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31241799

RESUMO

While some descriptions of ruminants' dietary adaptations suggest that the length of the intestinal tract reflects the proportion of grass or browse in the diet, this assumption has been questioned. We collated data on body mass (BM), as well as small intestine, caecum, colon/rectum, large and total intestine length in 68 ruminant species, and, while accounting for the phylogenetic structure of the dataset, evaluated both allometric scaling and the potential influence of diet, digestive physiology or climate proxies on measures of intestine length. Intestinal length generally scaled to BM at an exponent higher than the 0.33 expected due to geometry. Diet or digestive physiology proxies did not have an influence on any intestinal length measures, though some proxies indicating more arid natural habitats were positively correlated with measures of the large intestine. The relative size of a forestomach compartment, the omasum, was negatively correlated with intestine length. The results indicate that intestine length measures provide little indication of feeding type or digestive physiology, but rather indicate adaptations to aridity. Higher-than-geometry scaling of intestinal length may be related to the necessity of maintaining geometric (or metabolic) scaling of intestinal surface area while keeping gut diameter, and hence the diffusion distances, small. The way in which space trade-offs determine the macroanatomy of different organs in the abdominal cavity, such as the omasum and the intestine, deserves further investigation.


Assuntos
Intestinos/anatomia & histologia , Filogenia , Ruminantes/anatomia & histologia , Animais , Colo/anatomia & histologia , Dieta , Fezes , Tamanho do Órgão , Reto/anatomia & histologia , Especificidade da Espécie
10.
Arq. bras. med. vet. zootec. (Online) ; 71(1): 340-344, jan.-fev. 2019. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1038588

RESUMO

The morphology of the ruminal and omasal mucosa and hepatic parenchyma of 44 young bulls submitted to four types of concentrates were evaluated by varying the inclusion level of crude Glycerin - CG (0, 6, 12 and 18%). The variables evaluated were number of ruminal papillae per cm² of wall; area of the papillae and total absorption surface per cm² of wall; Mitotic index - MI, height and area of ruminal and omasal papillae; and hepatic morphology. The samples processed for inclusion in paraffin and stained with Hematoxylin-Eosin. The different levels of inclusion of CG in the diet did not interfere either in the number of papillae per cm2 of rumen wall (P= 0,70) or in the ruminal absorptive surface area (P= 0,89). Animals that received diets with levels 12 and 18% had higher MI of the ruminal epithelium (P< 0.01), but higher cell proliferation wasn't reflected in height gain and papillary area (P= 0,82). The omasal mucosa wasn't influenced by the inclusion of CG (MI e height gain and papillary area, P= 0,43, P= 0,56 e P= 0,9, respectively). The inclusion of GB in up to 18% of diet dry matter didn't alter the morphology of the rumen and omaso mucosa; and the integrity hepatic parenchyma.(AU)


Assuntos
Animais , Bovinos , Omaso/anatomia & histologia , Rúmen/anatomia & histologia , Ruminantes/anatomia & histologia , Glicerol/administração & dosagem , Fígado/anatomia & histologia
11.
J Morphol ; 280(2): 259-277, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30615226

RESUMO

The omasum is the third forestomach compartment of pecoran ruminants. It is assumed that the re-absorption of fluid present in the forestomach digesta (that facilitates particle sorting, digestion, and harvest of microbes) is its main function, so that less diluted digesta is submitted to enzymatic digestion in the lower digestive tract. Here, we evaluate measures of omasum size (representing 84 ruminant species in the largest data set) against body mass and proxies of the natural diet (%grass) or forestomach physiology (fluid throughput), using phylogenetically controlled models. The origin of specimens (free-ranging or captive) did not have an effect in the data set. Models with the best support invariably either included %grass or a physiology proxy in addition to body mass. These effects were not necessarily additive (affecting the intercept of the allometric regression), but often indicated a change in the allometric body mass-exponent with diet or physiology. Only models that allowed an influence on the allometric exponent yielded basic exponents compatible with predictions derived from geometry. Species that include more grass in their natural diet, or that have a "cattle-type" physiology marked by a high forestomach fluid throughput, generally have larger omasa. However, the existence of outliers, as well as the overall data pattern, suggest that this is not an obligatory morphophysiological condition. Circumstantial evidence is presented leading to the hypothesis that the comparatively small and less complex omasa of "moose-type" species do not necessarily represent an "original" state, but may be derived from more complex states by ontogenetic reduction and fusion of omasal laminae.


Assuntos
Tamanho Corporal , Dieta , Fenômenos Fisiológicos do Sistema Digestório , Omaso/anatomia & histologia , Ruminantes/anatomia & histologia , Animais , Animais de Zoológico/anatomia & histologia , Peso Corporal , Trato Gastrointestinal/anatomia & histologia , Análise dos Mínimos Quadrados , Filogenia
12.
Mol Phylogenet Evol ; 129: 70-76, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30121342

RESUMO

The musk ox (Ovibos moschatus) is the only surviving member of a group of Pleistocene North American musk ox genera (Praeovibos, Ovibos, Bootherium, Euceratherium, and Soergelia) whose taxonomy is uncertain. The helmeted musk ox (Bootherium bombifrons) and the woodland musk ox (Symbos cavifrons) have been synonymised as male and female forms of a single Nearctic species found from Alaska, in the north, to Texas, in the south. However, this reclassification has not been tested using molecular data, despite the potential to use ancient DNA to examine these late Pleistocene taxa. In the present study, we sequenced mitochondrial genomes from seven subfossil musk ox specimens (originally identified as Bootherium and/or Symbos), allowing us to evaluate the identity of these muskoxen, explore their phylogeography, and estimate the timeline for their evolution. We also used nuclear genomic data to determine the sex of six of our seven samples. Ultimately, our molecular data support the synonymisation of the North American muskoxen Bootherium and Symbos.


Assuntos
Fósseis , Ruminantes/anatomia & histologia , Ruminantes/genética , Alaska , Animais , Teorema de Bayes , DNA Antigo , DNA Mitocondrial/genética , Feminino , Genoma Mitocondrial , Masculino , Filogenia , Texas
13.
Syst Biol ; 67(1): 145-157, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28637223

RESUMO

The Late Cretaceous appearance of grasses, followed by the Cenozoic advancement of grasslands as dominant biomes, has contributed to the evolution of a range of specialized herbivores adapted to new diets, as well as to increasingly open and arid habitats. Many mammals including ruminants, the most diversified ungulate suborder, evolved high-crowned (hypsodont) teeth as an adaptation to tooth-wearing diets and habitats. The impact of different causes of tooth wear is still a matter of debate, and the temporal pattern of hypsodonty evolution in relation to the evolution of grasslands remains unclear. We present an improved time-calibrated molecular phylogeny of Cetartiodactyla, with phylogenetic reconstruction of ancestral ruminant diets and habitats, based on characteristics of extant taxa. Using this timeline, as well as the fossil record of grasslands, we conduct phylogenetic comparative analyses showing that hypsodonty in ruminants evolved as an adaptation to both diet and habitat. Our results demonstrate a slow, perhaps constrained, evolution of hypsodonty toward estimated optimal states, excluding the possibility of immediate adaptation. This augments recent findings that slow adaptation is not uncommon on million-year time scales.


Assuntos
Adaptação Fisiológica/fisiologia , Evolução Biológica , Pradaria , Ruminantes/classificação , Animais , Dieta , Fósseis , Filogenia , Poaceae , Ruminantes/anatomia & histologia , Ruminantes/genética
14.
Pesqui. vet. bras ; 38(3): 444-449, mar. 2018. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-964461

RESUMO

Neospora caninum has been described as a parasite that sporadically causes reproductive problems in goats. Several aspects of the pathogenesis of neosporosis in naturally infected goats remain to be established. The aims of the present study were to characterize the placental lesions in goats naturally infected by N. caninum and to evaluate several diagnostic techniques for effective detection of this protozoan in the goat placenta. Some placentas in this study originated from abortion and stillbirth in which there were severe lesions. The lesions were characterized mainly by necrosis involving the mesenchyme of the chorionic villi and trophoblast cells often alongside mononuclear inflammation and in some cases with neutrophilic infiltration. N. caninum DNA was detected in these placentas, but parasite structures were not visualized through immunohistochemistry (IHC). However, five of 11 placentas from N. caninum-infected goats that gave birth to healthy kids had histological lesions characterized by mononuclear inflammation. Of these 11 placentas, N. caninum DNA was detected in seven, and N. caninum tachyzoites were detected in only one of these seven placentas using IHC. The present study demonstrates that severe lesions in the placenta are associated with abortion and stillbirth in caprine neosporosis and the placental alterations are likely involved in abortion pathogenesis. Moreover, the results highlight the importance of using more than one diagnostic technique for the detection of the protozoan in placentas because N. caninum cannot be reliably detected by histological and immunohistochemical tests.(AU)


Neospora caninum é descrito como um parasito que causa problemas reprodutivos esporádicos em cabras. Muitos aspectos da patogênese da neosporose em cabras naturalmente infectadas ainda precisam ser estabelecidos. Os objetivos deste trabalho foram caracterizar as lesões placentárias em cabras naturalmente infectadas por N. caninum e avaliar as técnicas diagnósticas para a detecção efetiva do protozoário na placenta. Algumas placentas deste estudo são originárias de abortos e natimortos, nas quais havia lesões graves. As lesões foram classificadas principalmente por necrose envolvendo o mesênquima das vilosidades coriônicas e células trofoblásticas, geralmente associadas a infiltrado inflamatório mononuclear e em alguns casos infiltrado neutrofílico. O DNA do N. caninum foi detectado nestas placentas, porém estruturas parasitárias não foram visualizadas na imuno-histoquímica (IHQ). Entretanto, cinco das onze placentas de cabras infectadas, que deram à luz a conceptos saudáveis, apresentaram lesões histológicas caracterizadas por infiltrado inflamatório mononuclear. Destas 11 placentas, foi detectado DNA de N. caninum em sete e taquizoítos foram encontrados em apenas uma por meio de imuno-histoquímica. O presente estudo demonstra que abortos e natimortos na espécie caprina, causados pelo N. caninum estão associados a lesões acentuadas nas placentas, sendo que as mesmas estão envolvidas na patogênese do aborto. Os resultados também ressaltam a importância do uso de mais de uma técnica diagnóstica para a detecção do protozoário em placentas, pois o N. caninum não pode ser confiavelmente detectado somente pelos exames de histopatologia e imuno-histoquímica.(AU)


Assuntos
Animais , Ruminantes/anatomia & histologia , Neospora/parasitologia , Aborto Animal/diagnóstico
15.
PLoS One ; 12(10): e0185679, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29036194

RESUMO

Moschids are enigmatic pecoran ruminants whose phylogeny is still not fully understood. So far we know only little of the family's early evolutionary history and the origin of the modern genus, Moschus. Here we present a comprehensive description of cranial material, including the ear region and the dentition, of fossil moschid material from the Middle Miocene locality Steinheim am Albuch (13.5 Ma; Germany). This study provides the first exhaustive dataset for the cranial osteology of Micromeryx flourensianus, the most likely oldest true moschid. It furthermore reveals the presence of a second, so far undescribed moschid species, we here name Micromeryx? eiselei, in the abundant material from the locality. The two taxa can be clearly distinguished by characters of the skull, the ear region, the dentition, as well as by size. This evidences the sympatric occurrence of two moschid species in the locality Steinheim am Albuch.


Assuntos
Fósseis/anatomia & histologia , Ruminantes/anatomia & histologia , Crânio/anatomia & histologia , Dente/anatomia & histologia , Animais , Evolução Biológica , Orelha , Feminino , Alemanha , Imageamento Tridimensional , Masculino , Modelos Anatômicos , Filogenia
16.
Placenta ; 57: 216-222, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28864014

RESUMO

Although the pronghorn (Antilocapra americana) resembles an antelope, its nearest relatives are the giraffe and okapi. In this study we have examined the placentae of 6 pronghorns using lectin- and immunocytochemistry to identify giraffid and bovid features. Binucleate cells (BNC) of the placenta exhibited features intermediate between those of the giraffe and bovine; Dolichos biflorus agglutinin binding - strong in the bovine BNC and absent in the giraffe - was evident in only a subpopulation of BNC while binding to blood vessels, as in the giraffe. Binding of Phytolacca americana agglutinin resembled that of the giraffe and okapi whereas many other glycans were found in all four clades. PAG antigens were similar to bovine and okapi but not giraffe. In summary, although the pronghorn outwardly resembles an antelope, placental BNC show giraffid features. Although each clade has its own individual characteristics, there are far more similarities than differences between them, emphasizing the common ancestry of all four clades.


Assuntos
Placenta/citologia , Ruminantes/anatomia & histologia , Animais , Bovinos , Feminino , Girafas/anatomia & histologia , Girafas/metabolismo , Glicosilação , Imuno-Histoquímica , Placenta/metabolismo , Gravidez , Ruminantes/metabolismo
17.
Am J Vet Res ; 78(1): 80-84, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28029294

RESUMO

OBJECTIVE To determine corneal thickness of eyes of healthy goats, sheep, and alpacas by use of a portable spectral-domain optical coherence tomography (SD-OCT) device and evaluate intraoperator reliability for measurements. ANIMALS 11 female goats, 10 female sheep, and 11 (4 males and 7 females) alpacas. PROCEDURES Each animal was sedated, and gentle manual restraint was used to ensure proper positioning of the head and globe. Corneal pachymetry was performed (in triplicate) with a portable SD-OCT device on both eyes of each animal. All corneal measurements were obtained manually by use of the integrated caliper function. Corneal epithelial thickness (CET), corneal stromal thickness (CST), Descemet membrane thickness (DMT), and total corneal thickness (TCT) were measured twice on each image, and a mean value was calculated. RESULTS Mean ± SD values for CET, CST, DMT, and TCT were 96.1 ± 5.0 µm, 486.0 ± 10.3 µm, 36.8 ± 4.8 µm, and 616.9 ± 7.1 µm, respectively, for the goats; 111.6 ± 5.7 µm, 599.8 ± 10.0 µm, 31.0 ± 4.5 µm, and 741.1 ± 9.9 µm, respectively, for the sheep; and 147.4 ± 5.7 µm, 446.1 ± 7.4 µm, 44.5 ± 5.0 µm, and 634.8 ± 6.2 µm, respectively, for the alpacas. Intraclass correlations ranged from 0.49 to 0.83 for CET, CST, and TCT and from 0.13 to 0.36 for DMT. CONCLUSIONS AND CLINICAL RELEVANCE SD-OCT provided manual measurement of corneal thickness (CET, CST, and TCT) with clinically acceptable intraoperator reliability for eyes of healthy goats, sheep, and alpacas.


Assuntos
Camelídeos Americanos/anatomia & histologia , Córnea/anatomia & histologia , Ruminantes/anatomia & histologia , Animais , Paquimetria Corneana/veterinária , Substância Própria/anatomia & histologia , Feminino , Cabras/anatomia & histologia , Masculino , Posicionamento do Paciente , Valores de Referência , Reprodutibilidade dos Testes , Ovinos/anatomia & histologia , Tomografia de Coerência Óptica/veterinária
18.
Sci Rep ; 6: 29803, 2016 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-27405690

RESUMO

Although the initial formulation of modern concepts of adaptive radiation arose from consideration of the fossil data, rigorous attempts to identify this phenomenon in the fossil record are largely uncommon. Here I focus on direct evidence of the diet (through tooth-wear patterns) and ecologically-relevant traits of one of the most renowned fossil vertebrates-the Miocene ruminant Hoplitomeryx from the island of Gargano-to deepen our understanding of the most likely causal forces under which adaptive radiations emerge on islands. Results show how accelerated accumulation of species and early-bursts of ecological diversification occur after invading an island, and provide insights on the interplay between diet and demographic (population-density), ecological (competition/food requirements) and abiotic (climate-instability) factors, identified as drivers of adaptive diversification. A pronounced event of overpopulation and a phase of aridity determined most of the rate and magnitude of radiation, and pushed species to expand diets from soft-leafy foods to tougher-harder items. Unexpectedly, results show that herbivorous mammals are restricted to browsing habits on small-islands, even if bursts of ecological diversification and dietary divergence occur. This study deepens our understanding of the mechanisms promoting adaptive radiations, and forces us to reevaluate the role of diet in the origins and evolution of islands mammals.


Assuntos
Evolução Biológica , Herbivoria/fisiologia , Ruminantes/fisiologia , Dente/fisiologia , Animais , Ilhas , Ruminantes/anatomia & histologia , Dente/anatomia & histologia
19.
J Anat ; 229(3): 422-35, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27245372

RESUMO

Despite its growing use in anatomical and ecological studies, the morphological variability and ontogenetic development of the bony labyrinth have very rarely been investigated in ruminants. Here we study its morphology in 15 adult and 10 juvenile specimens in the three extant tragulid ruminant genera. Intraspecific and interspecific variability is quantified using morphometric and 3D geometric morphometrics analyses. The bony labyrinth of Tragulus, Hyemoschus, and Moschiola is strikingly different, clustering in clearly different morphospaces despite similar ecological adaptations. Although the bony labyrinths within two species of the same genus cannot be distinguished from each other based on the chosen semi-landmarks, discrete interspecific differences exist. We were able to show for the first time that an artiodactyl mammal in a late fetal stage possesses an almost fully formed bony labyrinth similar to that of adults. No significant change either occurs in size or morphology after ossification of the petrosal bone. Some intraspecific variation is observed on the shape of the lateral semi-circular canal, the size and shape of the common crus, the coil of the cochlea or the stapedial ratio. Variable structures are expected to be highly informative characters for a large cladistic analysis. They can be used for phylogenetic studies in ruminants. Incorporating juvenile specimens in studies is not problematic, as they fall within the morphological range of adults.


Assuntos
Orelha Interna/anatomia & histologia , Ruminantes/anatomia & histologia , Animais , Evolução Biológica , Feminino , Imageamento Tridimensional , Masculino , Filogenia , Especificidade da Espécie
20.
Am Nat ; 187(5): 576-91, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27104991

RESUMO

Differences among clades in their diversification patterns result from a combination of extrinsic and intrinsic factors. In this study, I examined the role of intrinsic factors in the morphological diversification of ruminants, in general, and in the differences between bovids and cervids, in particular. Using skull morphology, which embodies many of the adaptations that distinguish bovids and cervids, I examined 132 of the 200 extant ruminant species. As a proxy for intrinsic constraints, I quantified different aspects of the phenotypic covariation structure within species and compared them with the among-species divergence patterns, using phylogenetic comparative methods. My results show that for most species, divergence is well aligned with their phenotypic covariance matrix and that those that are better aligned have diverged further away from their ancestor. Bovids have dispersed into a wider range of directions in morphospace than cervids, and their overall disparity is higher. This difference is best explained by the lower eccentricity of bovids' within-species covariance matrices. These results are consistent with the role of intrinsic constraints in determining amount, range, and direction of dispersion and demonstrate that intrinsic constraints can influence macroevolutionary patterns even as the covariance structure evolves.


Assuntos
Evolução Biológica , Ruminantes/anatomia & histologia , Crânio/anatomia & histologia , Animais , Feminino , Masculino , Fenótipo , Filogenia , Ruminantes/classificação
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