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1.
J Zoo Wildl Med ; 55(1): 42-47, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38453486

RESUMO

The Masai giraffe (Giraffa camelopardalis tippelskirchi) is endangered in the wild, and successful reproduction in managed care is important to help maintain assurance populations of this highly charismatic subspecies. Detection of pregnancy in giraffes using hormonal monitoring requires multiple samples and cannot distinguish pregnancy from pseudopregnancy. A novel enzyme-linked immunosorbent assay that can detect pregnancy-specific protein B (PSPB) for pregnancy diagnosis with a single serum sample was developed from a reticulated giraffe (Giraffa camelopardalis reticulata) placenta. Seventy-eight serum samples were analyzed from three female Masai giraffes before and during five gestation periods that resulted in live calf births. Using an optical density cutoff of 0.2, the assay showed a sensitivity of 93% and specificity of 100% for all samples tested. At 59 d of gestation, sensitivity increased to 100%. The earliest pregnancy detection was at 40 d of gestation. This study documents the successful development of a blood-based PSPB assay for pregnancy diagnosis in Masai giraffe, which can help advance conservation efforts in this endangered species.


Assuntos
Girafas , Receptores Fc , Gravidez , Feminino , Animais , Reprodução
2.
J Zoo Wildl Med ; 55(1): 67-72, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38453489

RESUMO

Growing resistance to current antiparasitic medications, both in livestock and in zoological species under human care, makes it imperative to evaluate available drugs on the market, such as eprinomectin. In this prospective study, five males and one female of reticulated (Giraffa reticulata; n = 2), Masai (Giraffa tippelskirchii; n = 1), Nubian (Giraffa camelopardalis; n = 2), and hybrid subspecies (n = 1) of giraffe, received 1.5 mg/kg eprinomectin topically along the dorsum. Using high-performance liquid chromatography, concentrations of eprinomectin in plasma samples collected at 0, 4, 24, and 48 h, and 7, 14, 21, and 28 d were evaluated following drug administration. Complete blood cell counts and biochemistry panels were performed before (n = 6) and after (n = 3) eprinomectin administration. Samples for modified double centrifugal fecal flotation (n = 6) were evaluated prior to eprinomectin administration to evaluate for endoparasites and were repeated after the study (n = 5). Noncompartmental pharmacokinetic analysis was applied to the data. The observed maximum plasma concentration was 11.45 ng/ml and the time of observed maximum concentration was 2.67 d. The mean terminal half-life was 5.16 d. No adverse effects were observed related to eprinomectin administration and no blood work changes were observed. Parasite loads decreased (n = 3) or did not change (n = 2) after eprinomectin administration. The mean peak plasma concentration of eprinomectin in giraffe was similar to that achieved in cattle, despite using three times the dose.


Assuntos
Anti-Helmínticos , Girafas , Ivermectina/análogos & derivados , Masculino , Humanos , Feminino , Animais , Bovinos , Anti-Helmínticos/uso terapêutico , Estudos Prospectivos , Administração Tópica , Ivermectina/uso terapêutico
3.
J Zoo Wildl Med ; 55(1): 13-21, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38453483

RESUMO

Identifying common causes of mortality in zoo giraffe (Giraffa spp.) and okapi (Okapia johnstoni) provides an opportunity to help improve welfare and population management for these endangered species. Mortality reports from 1,024 giraffe and 95 okapi in zoos were compiled from the Species 360 Zoological Information Management Software (ZIMS) utilizing the Morbidity & Mortality Analysis tool. Thirty years of mortality reports (1991-2020) were evaluated to help identify trends and evaluate the impacts, if any, of changes over time in husbandry and management practices. The most common causes of death for giraffe from 1991 to 2015 were neonatal issues (234/845, 27.7%), trauma (213/845, 25.2%), noninfectious disease (190/845, 22.5%), and infectious disease (188/845, 22.2%). In comparison, the most common causes of mortality for giraffe from 2016 to 2020, were noninfectious disease (78/179, 43.6%), trauma (39/179, 21.8%), neonatal issues (39/179, 21.8%), and infectious disease (17/179, 9.5%). The most common cause of death for okapi from 1991 to 2015 were neonatal issues (29/64, 45.3%), infectious disease (13/64, 20.3%), noninfectious disease (11/64, 17.2%), and trauma (10/64, 15.6%). In comparison, the most common cause of death for okapi from 2016 to 2020 was noninfectious disease (15/31, 48.4%), neonatal issues (8/31, 25.8%), and infectious disease (5/31, 16.1%). The results suggest that zoo giraffids have had a relative decrease in mortality from infectious diseases in recent years, whereas death from noninfectious causes has increased significantly. Trauma-related giraffe mortalities and neonatal mortality in both giraffe and okapi, although decreasing in prevalence between time periods, continue to be important causes of death in zoos. This is the first descriptive mortality review for the Giraffidae family and provides data on potential giraffe and okapi health issues that zoos could proactively address.


Assuntos
Doenças Transmissíveis , Girafas , Doenças não Transmissíveis , Animais , Doenças Transmissíveis/veterinária , Programas de Assistência Gerenciada , Doenças não Transmissíveis/veterinária , Estudos Retrospectivos , Ruminantes
4.
Viruses ; 16(2)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38399948

RESUMO

Lumpy skin disease virus (LSDV) has recently undergone rapid spread, now being reported from more than 80 countries, affecting predominantly cattle and to a lesser extent, water buffalo. This poxvirus was previously considered to be highly host-range restricted. However, there is an increasing number of published reports on the detection of the virus from different game animal species. The virus has not only been shown to infect a wide range of game species under experimental conditions, but has also been naturally detected in oryx, giraffe, camels and gazelle. In addition, clinical lumpy skin disease has previously been described in springbok (Antidorcas marsupialis), an African antelope species, in South Africa. This report describes the characterization of lumpy skin disease virus belonging to cluster 1.2, from field samples from springbok, impala (Aepyceros melampus) and a giraffe (Giraffa camelopardalis) in South Africa using PCR, Sanger and whole genome sequencing. Most of these samples were submitted from wild animals in nature reserves or game parks, indicating that the disease is not restricted to captive-bred animals on game farms or zoological gardens. The potential role of wildlife species in the transmission and maintenance of LSDV is further discussed and requires continuing investigation, as the virus and disease may pose a serious threat to endangered species.


Assuntos
Antílopes , Girafas , Doença Nodular Cutânea , Vírus da Doença Nodular Cutânea , Animais , Bovinos , Vírus da Doença Nodular Cutânea/genética , Doença Nodular Cutânea/epidemiologia , Animais Selvagens , África do Sul , Surtos de Doenças/veterinária
5.
Vet Rec ; 193(11): 432-433, 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38038304

RESUMO

Georgina Mills discusses new work from the University of Glasgow examining how sounds might keep giraffes entertained.


Assuntos
Girafas , Animais , Animais de Zoológico
6.
Monoclon Antib Immunodiagn Immunother ; 42(6): 209-215, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38150189

RESUMO

Immunohistochemistry staining is an essential method in pathological diagnoses. Podoplanin (PDPN) is a specific maker of alveolar epithelium, lymphatic vessels, and glomeruli. In this study, we established a novel anti-giraffe PDPN (girPDPN) mAb, PMab-301, using the Cell-Based Immunization and Screening (CBIS) method. PMab-301 (mouse IgG1, kappa) detected girPDPN in various applications, such as flow cytometry, western blot, and immunohistochemistry. PMab-301 specifically stained type-I alveolar cells using formalin-fixed paraffin-embedded giraffe lung tissues. Our findings suggest the potential usefulness of PMab-301 for the pathophysiological analyses of giraffe tissues.


Assuntos
Anticorpos Monoclonais , Girafas , Cricetinae , Camundongos , Animais , Imuno-Histoquímica , Epitopos , Cricetulus , Glicoproteínas de Membrana , Especificidade de Anticorpos , Células CHO , Fatores de Transcrição
7.
Glob Chang Biol ; 29(23): 6693-6712, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37819148

RESUMO

Megaherbivores play "outsized" roles in ecosystem functioning but are vulnerable to human impacts such as overhunting, land-use changes, and climate extremes. However, such impacts-and combinations of these impacts-on population dynamics are rarely examined using empirical data. To guide effective conservation actions under increasing global-change pressures, we developed a socially structured individual-based model (IBM) using long-term demographic data from female giraffes (Giraffa camelopardalis) in a human-influenced landscape in northern Tanzania, the Tarangire Ecosystem. This unfenced system includes savanna habitats with a wide gradient of anthropogenic pressures, from national parks, a wildlife ranch and community conservation areas, to unprotected village lands. We then simulated and projected over 50 years how realistic environmental and land-use management changes might affect this metapopulation of female giraffes. Scenarios included: (1) anthropogenic land-use changes including roads and agricultural/urban expansion; (2) reduction or improvement in wildlife law enforcement measures; (3) changes in populations of natural predators and migratory alternative prey; and (4) increases in rainfall as predicted for East Africa. The factor causing the greatest risk of rapid declines in female giraffe abundance in our simulations was a reduction in law enforcement leading to more poaching. Other threats decreased abundances of giraffes, but improving law enforcement in both of the study area's protected areas mitigated these impacts: a 0.01 increase in giraffe survival probability from improved law enforcement mitigated a 25% rise in heavy rainfall events by increasing abundance 19%, and mitigated the expansion of towns and blockage of dispersal movements by increasing abundance 22%. Our IBM enabled us to further quantify fine-scale abundance changes among female giraffe social communities, revealing potential source-sink interactions within the metapopulation. This flexible methodology can be adapted to test additional ecological questions in this landscape, or to model populations of giraffes or other species in different ecosystems.


Assuntos
Girafas , Animais , Humanos , Feminino , Ecossistema , Mudança Climática , Tanzânia
8.
BMC Biol ; 21(1): 215, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37833744

RESUMO

BACKGROUND: In the speciation continuum, the strength of reproductive isolation varies, and species boundaries are blurred by gene flow. Interbreeding among giraffe (Giraffa spp.) in captivity is known, and anecdotal reports of natural hybrids exist. In Kenya, Nubian (G. camelopardalis camelopardalis), reticulated (G. reticulata), and Masai giraffe sensu stricto (G. tippelskirchi tippelskirchi) are parapatric, and thus, the country might be a melting pot for these taxa. We analyzed 128 genomes of wild giraffe, 113 newly sequenced, representing these three taxa. RESULTS: We found varying levels of Nubian ancestry in 13 reticulated giraffe sampled across the Laikipia Plateau most likely reflecting historical gene flow between these two lineages. Although comparatively weaker signs of ancestral gene flow and potential mitochondrial introgression from reticulated into Masai giraffe were also detected, estimated admixture levels between these two lineages are minimal. Importantly, contemporary gene flow between East African giraffe lineages was not statistically significant. Effective population sizes have declined since the Late Pleistocene, more severely for Nubian and reticulated giraffe. CONCLUSIONS: Despite historically hybridizing, these three giraffe lineages have maintained their overall genomic integrity suggesting effective reproductive isolation, consistent with the previous classification of giraffe into four species.


Assuntos
Girafas , Animais , Girafas/genética , Quênia , Genômica , Genoma , Hibridização Genética
9.
BMC Vet Res ; 19(1): 168, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37735412

RESUMO

BACKGROUND: Q fever and toxoplasmosis are economically important zoonoses as they cause considerable losses in livestock (cattle, sheep and goats) and wildlife (antelopes, giraffes, lions, and cheetahs) through reproductive disorders such as abortions and stillbirths. Q fever and toxoplasmosis testing in South Africa is conducted by the Agricultural Research Council-Onderstepoort Veterinary Research (ARC-OVR). However, both zoonoses are understudied and not monitored in South Africa as they are not considered controlled or notifiable diseases in the Animal Disease Act 35 of 1984. A retrospective study was conducted on Q fever (2007-2009) and toxoplasmosis (2007-2017) using diagnostic laboratory data at the ARC-OVR. Also, we report on sporadic abortion and stillbirth cases in livestock from diagnostic tissue samples submitted for Coxiella burnetii polymerase chain reaction (PCR) detection at the ARC-OVR. RESULTS: During 2007 to 2009, 766 animal samples were tested for C. burnetii antibodies and seropositivity was 0.9% (95%CI: 0.3-1.7) with sheep (1.9%; 95%CI: 0.6-4.4) having the highest seropositivity followed by cattle (0.7%; 95%CI: 0.09-2.6), while all goats (0.0%; 95%CI: 0.0-4.2) and wildlife (0.0%; 95%CI: 0.0-2.5) tested were negative. From 2007 to 2017, 567 sera were tested for T. gondii antibodies; overall seropositivity was 12.2% (95%CI: 9.6-15). Wildlife had highest seropositivity to T. gondii antibodies (13.9%; 95%CI: 9.0-19.7) followed by goats (12.9%; 95%CI: 9.2-17.4) and sheep (12.3%; 95%CI: 5.1-23.8) while seropositivity in cattle was 2.4% (95%CI: 0.06-12.9). Of 11 animals tested by C. burnetii PCR detection (2021-2022), 10 (91.0%) were positive. The amplicon sequences showed similarity to Coxiella burnetii strain 54T1 transposase gene partial coding sequence. CONCLUSIONS: We have confirmed the occurrence of the causative agents of Q fever and toxoplasmosis in livestock and wildlife in South Africa, with data limitations. These zoonoses remain of importance with limited information about them in South Africa. This study provides baseline information for future studies on Q fever and toxoplasmosis in South African livestock and wildlife, as well other African countries. Due to limited data collection experienced in this study, it is recommended that improvements in data collection samples tested should include associated factors such as sex, age, and breed of the animals.


Assuntos
Acinonyx , Antílopes , Antígenos de Grupos Sanguíneos , Doenças dos Bovinos , Coxiella burnetii , Girafas , Doenças das Cabras , Febre Q , Doenças dos Ovinos , Feminino , Gravidez , Animais , Bovinos , Ovinos , Coxiella burnetii/genética , Natimorto/epidemiologia , Natimorto/veterinária , Animais Selvagens , Febre Q/epidemiologia , Febre Q/veterinária , Estudos Retrospectivos , Gado , África do Sul/epidemiologia , Zoonoses , Anticorpos , Cabras , Doenças dos Bovinos/epidemiologia , Doenças das Cabras/epidemiologia , Doenças dos Ovinos/epidemiologia
10.
BMC Ecol Evol ; 23(1): 44, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37648992

RESUMO

Neck elongation has appeared independently in several tetrapod groups, including giraffes and sauropod dinosaurs on land, birds and pterosaurs in the air, and sauropterygians (plesiosaurs and relatives) in the oceans. Long necks arose in Early Triassic sauropterygians, but the nature and rate of that elongation has not been documented. Here, we report a new species of pachypleurosaurid sauropterygian, Chusaurus xiangensis gen. et sp. nov., based on two new specimens from the Early Triassic Nanzhang-Yuan'an Fauna in the South China Block. The new species shows key features of its Middle Triassic relatives, but has a relatively short neck, measuring 0.48 of the trunk length, compared to > 0.8 from the Middle Triassic onwards. Comparative phylogenetic analysis shows that neck elongation occurred rapidly in all Triassic eosauropterygian lineages, probably driven by feeding pressure in a time of rapid re-establishment of new kinds of marine ecosystems.


Assuntos
Dinossauros , Animais , China , Ecossistema , Girafas , Filogenia , Répteis
11.
J Wildl Dis ; 59(3): 472-478, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37269548

RESUMO

Congenital deformities and neoplasia are poorly documented in wildlife, owing to the difficulty of detection in wild populations. Congenital deformities may lead to premature mortality, thus reducing the chances of thorough documentation. Importantly, neoplasia diagnoses depend on either sampling suspicious lesions from living individuals or access to fresh, undisturbed carcasses, which can prove challenging. We describe five cases of suspected congenital cranial deformities (midfacial cleft, wry nose, and brachygnathia inferior) and two possible cases of cranial neoplasia (orbital bone mass and a soft tissue mass) opportunistically observed in wild giraffe (Giraffa spp.) across their range in Africa. Although cases are largely limited to subjective description because physical examination is often not possible, it is critical to document such observations to help identify and track potential health concerns in wild giraffe populations.


Assuntos
Girafas , Neoplasias , Animais , Ruminantes , Crânio , Animais Selvagens , Neoplasias/veterinária
12.
Proc Biol Sci ; 290(2001): 20230912, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37357852

RESUMO

Animal movement behaviours are shaped by diverse factors, including resource availability and human impacts on the landscape. We generated home range estimates and daily movement rate estimates for 149 giraffe (Giraffa spp.) from all four species across Africa to evaluate the effects of environmental productivity and anthropogenic disturbance on space use. Using the continuous time movement modelling framework and a novel application of mixed effects meta-regression, we summarized overall giraffe space use and tested for the effects of resource availability and human impact on 95% autocorrelated kernel density estimate (AKDE) size and daily movement. The mean 95% AKDE was 359.9 km2 and the mean daily movement was 14.2 km, both with marginally significant differences across species. We found significant negative effects of resource availability, and significant positive effects of resource heterogeneity and protected area overlap on 95% AKDE size. There were significant negative effects of overall anthropogenic disturbance and positive effects of the heterogeneity of anthropogenic disturbance on daily movements and 95% AKDE size. Our results provide unique insights into the interactive effects of resource availability and anthropogenic development on the movements of a large-bodied browser and highlight the potential impacts of rapidly changing landscapes on animal space-use patterns.


Assuntos
Ecossistema , Girafas , Humanos , Animais , Efeitos Antropogênicos , Movimento , África
13.
Zoo Biol ; 42(5): 632-643, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37154219

RESUMO

To improve animal welfare based on suitable social housing conditions, it is important to understand the factors that trigger high-stress responses. Wild giraffes live in a fission-fusion society and males and females are rarely in the same herd for a long period. The captive condition of belonging to a herd with the same individuals for months or years is uncommon in nature. To understand the effect of male presence on female stress levels, fecal glucocorticoid metabolite (fGCM) levels and social interactions in two captive female giraffes were investigated. Additionally, the effect of enclosure size and temperature on fGCM level and social interactions were examined. The results showed no significant difference in the fGCM levels of females based on male presence. The frequency of agonistic behavior by the dominant female toward the subordinate female was significantly increased when a male was present. The subordinate female was significantly less likely to approach the dominant female and showed decreased affiliative and agonistic interactions toward the dominant female when a male was present. The frequencies of agonistic interactions between females were higher in the small enclosure regardless of male presence. Low temperature triggered higher fGCM levels and increased agonistic interaction in an aged female. The findings of this study suggest that these multiple factors should be considered individually to promote the welfare of captive giraffes.


Assuntos
Girafas , Humanos , Masculino , Animais , Feminino , Girafas/fisiologia , Temperatura , Animais de Zoológico/metabolismo , Glucocorticoides/metabolismo , Fezes
14.
Sci Rep ; 13(1): 5558, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37142606

RESUMO

The ability to make inferences based on statistical information has so far been tested only in animals having large brains in relation to their body size, like primates and parrots. Here we tested if giraffes (Giraffa camelopardalis), despite having a smaller relative brain size, can rely on relative frequencies to predict sampling outcomes. We presented them with two transparent containers filled with different quantities of highly-liked food and less-preferred food. The experimenter covertly drew one piece of food from each container, and let the giraffe choose between the two options. In the first task, we varied the quantity and relative frequency of highly-liked and less-preferred food pieces. In the second task, we inserted a physical barrier in both containers, so giraffes only had to take into account the upper part of the container when predicting the outcome. In both tasks giraffes successfully selected the container more likely to provide the highly-liked food, integrating physical information to correctly predict sampling information. By ruling out alternative explanations based on simpler quantity heuristics and learning processes, we showed that giraffes can make decisions based on statistical inferences.


Assuntos
Girafas , Animais , Alimentos , Aprendizagem
15.
BMJ Open ; 13(4): e070533, 2023 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055203

RESUMO

INTRODUCTION: Atopic dermatitis (AD) is a chronic, inflammatory skin condition significantly affecting quality of life. A small randomised trial showed an approximately one-third lower incidence of AD in goat milk formula-fed compared with cow milk formula-fed infants. However, due to limited statistical power, AD incidence difference was not found to be significant. This study aims to explore a potential risk reduction of AD by feeding a formula based on whole goat milk (as a source of protein and fat) compared with a formula based on cow milk proteins and vegetable oils. METHODS AND ANALYSIS: This two-arm (1:1 allocation), parallel, randomised, double-blind, controlled nutritional trial shall enrol up to 2296 healthy term-born infants until 3 months of age, if parents choose to start formula feeding. Ten study centres in Spain and Poland are participating. Randomised infants receive investigational infant and follow-on formulas either based on whole goat milk or on cow milk until the age of 12 months. The goat milk formula has a whey:casein ratio of 20:80 and about 50% of the lipids are milk fat from whole goat milk, whereas the cow milk formula, used as control, has a whey:casein ratio of 60:40 and 100% of the lipids are from vegetable oils. The energy and nutrient levels in both goat and cow milk formulas are the same. The primary endpoint is the cumulative incidence of AD until the age of 12 months diagnosed by study personnel based on the UK Working Party Diagnostic Criteria. The secondary endpoints include reported AD diagnosis, measures of AD, blood and stool markers, child growth, sleep, nutrition and quality of life. Participating children are followed until the age of 5 years. ETHICS AND DISSEMINATION: Ethical approval was obtained from the ethical committees of all participating institutions. TRIAL REGISTRATION NUMBER: NCT04599946.


Assuntos
Dermatite Atópica , Eczema , Hipersensibilidade Alimentar , Girafas , Animais , Feminino , Bovinos , Leite , Fórmulas Infantis , Dermatite Atópica/epidemiologia , Dermatite Atópica/prevenção & controle , Caseínas , Cabras , Qualidade de Vida , Eczema/epidemiologia , Eczema/prevenção & controle , Lipídeos , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
Anat Rec (Hoboken) ; 306(10): 2646-2651, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36929340

RESUMO

The giraffe juvenile has different proportions of head to neck from the adult. The head just about doubles in size from the juvenile to adult, whereas the neck increases almost 4.5× (roughly four times) in length. The T1 posterior dorsal vertebral width of the newborn is clearly wider than in the adult where it is narrow. In the okapi, the dorsal vertebral width is narrow in both juvenile and adult. The giraffe neck changes in ontogeny anisometrically. In the okapi the changes are more isometric. The giraffe juvenile vertebrae are shorter and do not have fused the cranial epiphyseal plates. That facilitates anterior elongation-growth. The ventral tubercles are undeveloped. The juvenile T1 is wide caudally unlike the adult. This may be a similarity to a gelocid (Gelocidae) ancestor of the giraffe.


Assuntos
Girafas , Animais , Pescoço , Coluna Vertebral
17.
Plast Reconstr Surg ; 152(3): 669-680, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36790779

RESUMO

BACKGROUND: Serendipitously, a dead giraffe provided opportunity to study its vascular anatomy. Comparative animal studies have revealed important information for designing new flaps and new microsurgical techniques. So, do giraffe's patches support a thermal window concept, do animals with similar markings and habitat have a similar thermoregulatory role, and could results offer new insight into human thermoregulation and free tissue transfer? METHODS: Previously described lead-oxide arterial-only injection studies, of a single giraffe, zebra, Africa wild dog, and spotted jaguar, all with wire-encircled pigmented patches; and archival human, pig, dog, cat, and rabbit studies, were compared. RESULTS: Each giraffe patch was supplied by just a single artery (angiosome) averaging 0.9 mm diameter, that divided near its center and sent dense, long, parallel, radiating spoke-wheel branches averaging 0.62 mm diameter to the patch margin, continuing as reduced-caliber choke anastomoses averaging 0.8 mm to link adjacent patch angiosomes. Uniquely arranged large veins, with an average of 1.66 mm, encircled the patches in the pale skin paralleled by arteriae comitantes averaging 0.22 mm. These arteries, connected to patch angiosomes, filled the veins intermittently by means of arteriovenous (A-V) shunts averaging 0.12 mm in diameter of magnitude never seen before in any species studied. None of the other three animals had angiosome territories matching their pigmented fur, or significant A-V filling. CONCLUSIONS: This study supports the "thermostatic" concept of the giraffe skin patches, with A-V shunts playing a major role. It affirms the need for further studies of these shunts in human thermoregulation and other flow regulations in physiology, pathology, and free tissue transfer.


Assuntos
Girafas , Humanos , Animais , Suínos , Coelhos , Regulação da Temperatura Corporal , Retalhos Cirúrgicos , Veias
18.
Science ; 379(6633): eade3392, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36795806

RESUMO

Hou et al. challenged the giraffoid affinity of Discokeryx and its ecology and behavior. In our response we reiterate that Discokeryx is a giraffoid that, along with Giraffa, shows extreme evolution of head-neck morphologies that were presumably shaped by selective pressure from sexual competition and marginal environments.


Assuntos
Aclimatação , Evolução Biológica , Girafas , Seleção Sexual , Seleção Genética , Animais , Girafas/genética , Girafas/fisiologia
19.
Science ; 379(6633): eadd9559, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36795824

RESUMO

Wang et al. (Research Articles, 3 June 2022, eabl8316) reported an early Miocene giraffoid that exhibited fierce head-butting behavior and concluded that sexual selection promoted head-neck evolution in giraffoids. However, we argue that this ruminant is not a giraffoid and thus that the hypothesis that sexual selection promoted giraffoid head-neck evolution is not sufficiently supported.


Assuntos
Adaptação Fisiológica , Evolução Biológica , Girafas , Seleção Sexual , Aclimatação , Adaptação Fisiológica/genética , Cabeça , Pescoço , Animais , Girafas/anatomia & histologia , Girafas/genética , Girafas/fisiologia
20.
Sci Rep ; 13(1): 1959, 2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737637

RESUMO

Giraffe skin disease (GSD), a condition that results in superficial lesions in certain giraffe (Giraffa spp.) populations, has emerged as a potential conservation threat. Preliminary findings suggested that individuals with GSD lesions move with greater difficulty which may in turn reduce their foraging efficiency or make them more vulnerable to predation. A current known threat to some giraffe populations is their mortality associated with entrapment in wire snares, and the morbidity and potential locomotor deficiencies associated with wounds acquired from snares. The goal of our study was to quantify the locomotor kinematics of free-ranging Nubian giraffe (G. camelopardalis camelopardalis) in Murchison Falls National Park (MFNP), Uganda, and compare spatiotemporal limb and neck angle kinematics of healthy giraffe to those of giraffe with GSD lesions, snare wounds, and both GSD lesions and snare wounds. The presence of GSD lesions did not significantly affect spatiotemporal limb kinematic parameters. This finding is potentially because lesions were located primarily on the necks of Nubian giraffe in MFNP. The kinematic parameters of individuals with snare wounds differed from those of healthy individuals, resulting in significantly shorter stride lengths, reduced speed, lower limb phase values, and increased gait asymmetry. Neck angle kinematic parameters did not differ among giraffe categories, which suggests that GSD neck lesions do not impair normal neck movements and range of motion during walking. Overall, MFNP giraffe locomotor patterns are largely conservative between healthy individuals and those with GSD, while individuals with snare wounds showed more discernible kinematic adjustments consistent with unilateral limb injuries. Additional studies are recommended to assess spatiotemporal limb kinematics of giraffe at sites where lesions are found predominantly on the limbs to better assess the potential significance of GSD on their locomotion.


Assuntos
Girafas , Dermatopatias , Animais , Dermatopatias/patologia , Ruminantes , Marcha , Locomoção
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