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1.
Front Vet Sci ; 10: 1288451, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026662

RESUMO

An adult male ring-tailed lemur (Lemur catta) from a biopark of northern Italy was submitted to necropsy. A multi-organ parasitic infection was macroscopically evident. Abundant sero-hemorrhagic fluid with larval parasites was present in all cavities. The microscopic evaluation of parasites and the molecular characterization revealed the presence of Cysticercus longicollis (the larval stage of Taenia crassiceps). Histology of liver, lungs, intestine and urinary bladder revealed several larval parasites surrounded by a severe lymphocytic infiltrate, fibrous tissue and hemorrhages. This is the first report of a ring-tailed lemur with an infection of C. longicollis in Italy. The source of infection is still not known however, the discovery of this parasite in a captive lemur poses more attention on the control of parasitic diseases implementing monitoring tests and biosecurity measures.

2.
Vet Parasitol Reg Stud Reports ; 41: 100876, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37208075

RESUMO

Toxoplasmosis is caused by the ubiquitous Apicomplexan protozoan Toxoplasma gondii. This pathogen affects domestic and wildlife species, but prosimians including ring-tailed lemurs (Lemur catta) are highly susceptible to infection with high mortality rates. Avian species are considered resistant to infection and are often used in surveillance efforts to determine genotypes of T. gondii present in geographical areas. This study describes the gross and histologic lesions of an outbreak of toxoplasmosis in a university-run zoological collection involving three ring-tailed lemurs and a peahen (Pavo cristatus). DNA was extracted from the liver of the lemurs and peahen to determine the genotype of T. gondii by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP), which revealed that all samples were ToxoDB PCR-RFLP genotype #5 (haplogroup 12) that is common in wildlife in North America.


Assuntos
Lemur , Toxoplasma , Toxoplasmose Animal , Animais , Animais Selvagens , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Genótipo
3.
Acta Parasitol ; 68(2): 468-472, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37099074

RESUMO

BACKGROUND: Different rodent species serve as natural intermediate hosts for carnivore tapeworm Taenia crassiceps. However, this cestode occasionally infects various dead-end hosts including humans and other primates and may cause serious pathological implications with potentially fatal outcome. In this paper, we present subcutaneous cysticercosis caused by T. crassiceps, found in a previously healthy 17-years-old male ring-tailed lemur (Lemur catta) in a Serbian Zoo. CASE PRESENTATION: The animal was presented to a veterinarian with a history of periarticular subcutaneous swelling in medial right knee region. After fine needle aspiration revealed cycticerci-like structures, a surgery was performed for complete extraction of the incapsulated multicystic mass containing numerous cysticerci. Collected material was sent for parasitological, histological and molecular analysis. One month after surgery, the lemur died due to respiratory failure unrelated to cysticercosis. Based on morphological features of large and small hooks and characteristic proliferation of cysticerci, a metacestode of T. crassiceps was identified, which was confirmed after sequencing of obtained amplicons and comparing them to the GenBank database. CONCLUSIONS: This is one of the few reported cases of T. crassiceps cysticercosis in a ring-tailed lemur, and the first one in Serbia. This endangered species seem to be more sensitive for T. crassiceps than other non-human primates, which represents serious conservation challenge for captive animals. Due to zoonotic nature of the parasite, challenging diagnosis, severity of the disease, difficult treatment and possible fatalities, high biosecurity measures are of particular importance, especially in endemic regions.


Assuntos
Cisticercose , Lemur , Taenia , Animais , Masculino , Taenia/genética , Lemur/parasitologia , Sérvia , Cisticercose/diagnóstico , Cisticercose/veterinária , Cisticercose/parasitologia , Cysticercus , Roedores
4.
Zoo Biol ; 42(1): 26-37, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35614574

RESUMO

To robustly study zoo animal cognition and provide effective enrichment, we must provide animals with carefully designed apparatus made from appropriate (safe, attractive, practical) materials. However, all too often, this design phase is overlooked or omitted from the literature. We evaluated how a troop of 12 ring-tailed lemurs (Lemur catta) explored a range of novel materials and whole foods during outdoor social testing. These items were not intended to test cognition or be enriching; rather we viewed them as the potential "building blocks" from which to build our future apparatus. Lemurs preferred to explore wooden surfaces, but had no preference for manipulanda made from different materials. Large amounts of metal and untreated wood should be avoided in the future; metal produced too much heat and glare, and wood was damaged by biting/chewing. Lemurs used one or two hands to explore manipulanda, and simple touching was more common than twisting or pulling. However, lemurs were most likely to explore by smell than touch or by mouth. Social testing preserved "normal" conditions for the lemurs, including natural food stealing and scrounging in high- and low-ranking individuals, respectively. Our findings culminated in the development of a static, low-level cognitive task apparatus, constructed from modular plastic units. We encourage other researchers to report how they develop cognitive and enrichment apparatuses and consider a similar preference-testing approach.


Assuntos
Lemur , Lemuridae , Strepsirhini , Animais , Animais de Zoológico , Cognição
5.
Animals (Basel) ; 14(1)2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38200871

RESUMO

In the setting of the recent COVID-19 pandemic, transmission of SARS-CoV-2 to animals has been reported in both domestic and wild animals and is a matter of concern. Given the genetic and functional similarities to humans, non-human primates merit particular attention. In the case of lemurs, generally considered endangered, they are believed to be susceptible to SARS-CoV-2 infection. We have conducted a study for evidence of SARS-CoV-2 infection among the 43 lemurs of Mundomar, a zoological park in Benidorm, Spain. They belong to two endangered lemur species, 23 black-and-white ruffed lemurs (Varecia variegata) and 20 ring-tailed lemurs (Lemur catta). Health assessments conducted in 2022 and 2023 included molecular analyses for SARS-CoV-2 RNA of oral and rectal swabs using two different RT-qPCR assays, always with negative results for SARS-CoV-2 in all animals. The assessment also included serological testing for antibodies against the receptor-binding domain (RBD) of the spike protein (S) of SARS-CoV-2, which again yielded negative results in all animals except one black-and-white ruffed lemur, supporting prior infection of that animal with SARS-CoV-2. Our data, while not indicating a high susceptibility of lemurs to SARS-CoV-2 infection, show that they can be infected, adding to the existing information body on potential ways for SARS-CoV-2 virus spreading in zoos, highlighting the need for animal surveillance for the virus.

6.
Vet Pathol ; 59(1): 169-172, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34493121

RESUMO

The cestode Hymenolepis nana is a common parasite of humans and mice. Fecal shedding in the absence of clinical disease has previously been reported in ring-tailed lemurs (Lemur catta). This report describes fatal, disseminated H. nana cestodiasis infection in an aged ring-tailed lemur in a zoological collection. The parasites were associated with severe multifocal to coalescing and regionally extensive pyogranulomatous hepatitis and moderate multifocal pneumonia. The morphology of the parasites was highly unusual. Profiles were variably sized, ellipsoid to irregularly serpiginous, lined by a thin tegument, and filled with lightly eosinophilic fibrillar stroma and numerous, round basophilic cells. Polymerase chain reaction targeting a portion of the 18S rRNA gene and DNA sequencing of the amplicon showed 100% homology with H. nana.


Assuntos
Hymenolepis nana , Lemur , Animais , Fezes , Camundongos
7.
Animals (Basel) ; 11(11)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34827806

RESUMO

Responses to stress are unavoidable, adaptive mechanisms in humans and non-human animals. However, in humans, chronic stress has been linked to poor health outcomes and early mortality. Allostatic load, the physiologic dysregulation that occurs when an organism is exposed to chronic stressors, has been used to assess stress in humans; less work has been done using non-human primates. Our aim was to determine the relationship between allostatic load in ring-tailed lemurs (Lemur catta) under human care and potentially stressful individual, social, medical and husbandry factors, as well a sex and age. An allostatic load index (ALI) was calculated for 38 lemurs using six biomarkers measured in serum (albumin, cortisol, dehydroepiandrosterone-sulfate, DNA damage, glucose and prostaglandin E2). Potentially stressful factors were recorded over the lifetime of each lemur using medical and husbandry records. Animals with a higher percentage of time spent indoors, those kept in smaller average group sizes, and those with fewer minor group composition changes had, or tended to have, higher ALI. There was no relationship between ALI and sex or age. Some social and husbandry factors were associated with allostatic load in lemurs, indicating that this index may be a useful tool in assessing and determining factors contributing to stress of lemurs and other animals under human care.

8.
Animals (Basel) ; 11(10)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34679832

RESUMO

The mobility of the primate tongue allows for the manipulation of food, but, in addition, houses both general sensory afferents and special sensory end organs. Taste buds can be found across the tongue, but the ones found within the fungiform papillae on the anterior two thirds of the tongue are the first gustatory structures to come into contact with food, and are critical in making food ingestion decisions. Comparative studies of both the macro and micro anatomy in primates are sparse and incomplete, yet there is evidence that gustatory adaptation exists in several primate taxa. One is the distally feathered tongues observed in non-destructive nectar feeders, such as Eulemur rubriventer. We compare both the macro and micro anatomy of three lemurid species who died of natural causes in captivity. We included the following two non-destructive nectar feeders: Varecia variegata and Eulemur macaco, and the following destructive flower feeder: Lemur catta. Strepsirrhines and tarsiers are unique among primates, because they possess a sublingua, which is an anatomical structure that is located below the tongue. We include a microanatomical description of both the tongue and sublingua, which were accomplished using hematoxylin-eosin and Masson trichrome stains, and scanning electron microscopy. We found differences in the size, shape, and distribution of fungiform papillae, and differences in the morphology of conical papillae surrounding the circumvallate ones in all three species. Most notably, large distinct papillae were present at the tip of the tongue in nectar-feeding species. In addition, histological images of the ventro-apical portion of the tongue displayed that it houses an encapsulated structure, but only in Lemur catta case such structure presents cartilage inside. The presence of an encapsulated structure, coupled with the shared morphological traits associated with the sublingua and the tongue tip in Varecia variegata and Eulemur macaco, point to possible feeding adaptations that facilitate non-destructive flower feeding in these two lemurids.

9.
Primates ; 62(2): 417-430, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33459940

RESUMO

Vocalizations are used by group-living animals as aggressive and submissive signals during agonistic interactions, and are also used to maintain dominance hierarchies in many species. For gregarious strepsirrhines with large vocal repertoires and differentiated dominance ranks like the ring-tailed lemur (Lemur catta), agonistic vocalization use is important to study to better understand their social adaptations.To determine whether ring-tailed lemur vocalizations such as the yip, cackle, twitter, chutter, and plosive bark were used as aggressive or submissive signals during agonism and uttered at different rates by males of differing dominance ranks and ages, 565 h of focal data were collected on 31 individual males aged ≥ 1 year from Beza Mahafaly Special Reserve, Madagascar. Yip, cackle, and twitter vocalizations were consistently used during agonistic submissive interactions with both males and females, chutter vocalizations were used during aggressive agonistic interactions with males and submissive agonistic interactions with males and females, and plosive bark vocalizations were used across behavioural contexts but not particularly during agonism. Males of all ages employed all vocalizations, and while low-ranking males uttered yip calls at higher rates, males of all dominance ranks uttered cackle, twitter, chutter, and plosive bark vocalizations. These results advance our knowledge of how male lemurs utilize agonistic vocalizations to maintain inter-individual relationships with males and females, and improve our overall understanding of the function of different agonistic vocalizations in wild lemurs.


Assuntos
Comportamento Agonístico , Lemur/fisiologia , Vocalização Animal , Animais , Feminino , Masculino , Comportamento Social , Predomínio Social
10.
Folia Primatol (Basel) ; 91(6): 575-594, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756063

RESUMO

Affiliative vocalizations occur across primate taxa and may be used to maintain spatial cohesion and/or to regulate social interactions in group-living species. For gregarious strepsirhines like the ring-tailed lemur (Lemur catta), with large vocal repertoires and several distinct affiliative vocalizations including the chirp and wail, it is important to understand behavioural usage of these vocalizations to gain insight into their social interactions. To determine whether chirp and wail vocalizations facilitate group cohesion, regulate interactions to achieve socially positive outcomes, and are correlated with differences in individual characteristics such as dominance rank and age, I collected 565 h of focal data on 31 males aged ≥1 year at Beza Mahafaly Special Reserve, Madagascar, from March to July 2010. I found that chirp and wail vocalizations occurred at the highest rates during group-wide travel compared to other behaviours. Although nearest neighbour distance did not influence calling rate, focal animals maintained the same distance or were located closer to nearest neighbours after calling. Both chirp and wail calls were heard in behavioural contexts without agonism rather than agonistic contexts. No relationship was found between male calling rate and dominance rank or age, although the chirp showed a non-significant tendency to be produced at higher rates by younger males. Overall, my results indicated that ring-tailed lemur males of all ages and dominance ranks used both chirp and wail vocalizations as contact calls during group-wide travel events, helping individuals maintain proximity to other group members during movement. Chirp and wail vocalizations may additionally help regulate the caller's social interactions and promote increased tolerance from conspecifics. These findings add to our understanding of the breadth of communication behaviour in wild lemurs, thus furthering our knowledge of the social lives and cognitive abilities of strepsirhines. Through examining the complexity of vocalization use by a living lemur species with a communication system much like early social primates, we gain broad insight into the evolution of primate sociality.


Assuntos
Comunicação Animal , Lemur/fisiologia , Comportamento Social , Fatores Etários , Animais , Locomoção , Madagáscar , Masculino , Predomínio Social
11.
Physiol Behav ; 226: 113125, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32771504

RESUMO

The aim of the present study was to assess the occurrence of spontaneous food preferences in zoo-housed ring-tailed lemurs and to analyze whether these preferences correlate with nutrient composition. Using a two-alternative choice test three female and one male Lemur catta were repeatedly presented with all possible binary combinations of 12 types of food which are part of their diet in captivity and found to display the following rank order of preference: apple > sweet potato > melon > beetroot > carrot > egg > eggplant > pumpkin > cucumber > tomato > cabbage > mealworm. Correlational analyses revealed a highly significant positive correlation between this food preference ranking and the total carbohydrate and sucrose contents of the foods (p < 0.01, respectively). No other significant correlations with any other macro- or micronutrient were found. These results suggest that zoo-housed ring-tailed lemurs are not opportunistic, but selective feeders with regard to maximizing their net gain of energy as only the content of carbohydrates, but not the contents of total energy, proteins or lipids significantly correlated with the displayed food preferences. Further, we found that ring-tailed lemurs that were raised on a vegetable-based diet did not significantly differ in their food preferences, and in particular in their predilection for food items high in carbohydrates, from animals that had previously been fed a fruit-based diet. This suggests that the lemurs' preference for carbohydrate-rich food items may be innate and not affected by experience with different diets.


Assuntos
Preferências Alimentares , Lemur , Animais , Dieta/veterinária , Carboidratos da Dieta , Feminino , Masculino , Nutrientes
12.
J Zoo Wildl Med ; 51(2): 308-320, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32549560

RESUMO

Cardiac disease has been recognized as a major cause of death in captive nonhuman primates, which necessitates diagnostic (imaging) techniques to screen for and diagnose preclinical and clinical stages of possible cardiac conditions. Echocardiography is currently the most commonly used diagnostic tool for evaluation of cardiac anatomy and function. Complete with thoracic radiography and blood levels of two cardiac biomarkers, N-terminal probrain natriuretic peptide (NT-proBNP) and cardiac troponin T (cTnT), it gives an extensive examination of the cardiorespiratory system. The purpose of this cross-sectional cohort study is to describe normal thoracic anatomy using thoracic radiography, and to provide normal values for echocardiographic measurements in 20 ring-tailed lemurs (Lemur catta). Additionally, cardiac biomarkers were determined. Three radiographic projections of the thoracic cavity and a complete transthoracic echocardiography were performed in 20 clinically healthy ring-tailed lemurs during their annual health examinations. Similar standard right parasternal and left apical echocardiographic images were obtained as described in dogs and cats and normal values for routine two-dimensional (2D-), time-motion (M-) and Doppler mode measurements were generated. Furthermore, a noninvasive smartphone base ECG recording and blood concentrations of cardiac biomarkers were obtained. Other radiographic measurements are provided for the skeletal and respiratory systems such as the trachea to inlet ratio and tracheal inclination. Knowledge of the normal radiographic thoracic and echocardiographic anatomy and function are fundamental for the diagnosis and follow-up of cardiac disease in affected individuals and for species screening, and will be of added value in future research in and conservation of this endangered species.


Assuntos
Coração/diagnóstico por imagem , Lemur/anatomia & histologia , Cavidade Torácica/diagnóstico por imagem , Animais , Ecocardiografia/veterinária , Espécies em Perigo de Extinção , Feminino , Masculino , Radiografia Torácica/veterinária
13.
Ir Vet J ; 73: 9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32551091

RESUMO

BACKGROUND: There is very little data on the optimal anaesthetic management of ring-tailed lemurs, and the available information is mostly based on extrapolation from other species. In addition, a thorough pre-anaesthetic assessment of lemurs might not be possible without prior chemical immobilization, making a safe immobilization protocol essential. CASE PRESENTATION: Three ring-tailed lemurs (Lemur catta) were immobilized using a combination of intramuscular alfaxalone (5 mg/kg), butorphanol (0.2 mg/kg), and midazolam (0.2 mg/kg), at the University College Dublin Veterinary Hospital. One lemur was anaesthetised once, two lemurs twice, amounting to five anaesthetic events. Conversion to general anaesthesia was warranted in all five occasions, and anaesthesia was maintained with either sevoflurane in oxygen or alfaxalone infusion. The immobilization protocol provided an adequate duration of deep sedation for diagnostic procedures and in some occasions allowed the intubation of the trachea. Analgesia was also provided for minor procedures. No major complications were noted with the protocol used. CONCLUSIONS: The combination of intramuscular alfaxalone, butorphanol and midazolam provided a clinically useful sedation/immobilization in ring-tailed lemurs with only minor complications such as mild hypothermia, hypotension, hypoventilation and bradycardia. This protocol could be considered in ring-tailed lemurs that need to be immobilized for minor procedures, or as a pre-anaesthetic premedication, especially if a full pre-anaesthetic clinical exam is not possible.

14.
Am J Primatol ; 82(4): e23095, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32003047

RESUMO

Habitat fragmentation is an increasingly serious issue affecting primates in most regions where they are found today. Populations of Lemur catta (ring-tailed lemur) in Madagascar's south-central region are increasingly restricted to small, isolated forest fragments, surrounded by grasslands or small-scale agriculture. Our aim was to evaluate the potential for population viability of L. catta in nine forest fragments of varying sizes (2-46 ha, population range: 6-210 animals) in south-central Madagascar, using a set of comparative, quantitative ecological measures. We used Poisson regression models with a log link function to examine the effects of fragment size, within-fragment food availability, and abundance of matrix resources (food and water sources) on L. catta population sizes and juvenile recruitment. We found a strong association between overall population size and (a) fragment size and (b) abundance of key food resources Melia azedarach and Ficus spp. (per 100 m along transect lines). Juvenile recruitment was also associated with fragment size and abundance of the two above-mentioned food resources. When the largest population, an outlier, was removed from the analysis, again, the model containing fragment size and abundance of M. azedarach and Ficus spp. was the best fitting, but the model that best predicted juvenile recruitment contained only fragment size. While our results are useful for predicting population presence and possible persistence in these fragments, both the potential for male dispersal and the extent of human disturbance within most fragments play crucial roles regarding the likelihood of long-term L. catta survival. While seven of the nine fragments were reasonably protected from human disturbance, only three offered the strong potential for male dispersal, thus the long-term viability of many of these populations is highly uncertain.


Assuntos
Ecossistema , Florestas , Lemur/fisiologia , Animais , Conservação dos Recursos Naturais , Dieta , Feminino , Ficus , Frutas , Atividades Humanas , Madagáscar , Masculino , Melia azedarach , Densidade Demográfica
15.
Zoo Biol ; 38(3): 281-291, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30888079

RESUMO

The ring-tailed lemur (Lemur catta), one of the most iconic and widely recognized primates in the world, is threatened in its native range and classified as endangered by the International Union for Conservation of Nature. The global conservation strategy for the species includes ex situ conservation efforts led by zoological institutions in the framework of regional captive breeding programs. To maximize the conservation of genetic diversity and optimize breeding programs, an accurate pedigree must be established in captive populations. Our study documents the formation and subsequent monitoring of a large ring-tailed lemur group in a French zoological institution. Based on staff's behavioral observations and DNA analyses using 11 microsatellite markers, we were able to document the survival and reproduction rates of the lemurs in this situation and reconstruct the pedigree of infants born in the institution. In total, 22 of the 28 imported animals as well as 4 locally born individuals gave birth to 58 infants of which 28 survived. The consistent genotypes obtained from the 53 sampled animals allowed us to identify 25 of the sires and 27 of the dams for the 28 surviving infants. A total of 12 different females and 14 different males produced the 28 surviving infants, suggesting that no individual dominates reproduction. This pioneering study has practical applications for the captive management of the species, which can be raised to the individual level instead of the group level.


Assuntos
Cruzamento , Lemur/genética , Lemur/fisiologia , Animais , Animais de Zoológico/genética , Conservação dos Recursos Naturais , Feminino , França , Masculino , Repetições de Microssatélites , Linhagem
16.
Vet Anaesth Analg ; 45(3): 351-356, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29625917

RESUMO

OBJECTIVE: To evaluate the clinical effects and quality of sedation, induction, maintenance and recovery in Lemur catta after dexmedetomidine-butorphanol-midazolam sedation and alfaxalone anaesthesia. STUDY DESIGN: Prospective, observational study. ANIMALS: Six male L. catta weighing 3.0 ± 0.6 kg undergoing surgical castration. METHODS: Lemurs were sedated with intramuscular dexmedetomidine (0.015 mg kg-1), butorphanol (0.2 mg kg-1) and midazolam (0.2 mg kg-1). Anaesthesia was induced with intravenous alfaxalone 0.5 mg kg-1 over 60 seconds; further boluses were administered until tracheal intubation was feasible and final dose recorded. Alfaxalone continuous infusion was used to maintain anaesthesia. Atipamezole (0.15 mg kg-1) was administered during recovery. The quality of sedation, induction, intubation, maintenance and recovery was assessed using a scoring system. Physiological parameters were recorded during sedation, maintenance and recovery. RESULTS: Sedation was achieved in 13.6 ± 5.6 minutes and no reactions were observed during handling or venepuncture. The mean dose of alfaxalone required for induction and maintenance was 2.09 ± 0.65 and 0.08 ± 0.02 mg kg-1 minute-1, respectively. Quality of induction, intubation and maintenance was good in almost all animals. Mild self-limiting muscle twitching was observed after alfaxalone administration in three animals. Cardiorespiratory function was stable in all animals but one. One lemur showed respiratory depression and required oxygen administration and manual ventilation. The mean maintenance time was 29.2 ± 7.4 minutes. The mean times from the end of alfaxalone administration to extubation, atipamezole administration and full recovery were: 15.3 ± 8.0, 22.2 ± 4.6 and 60.0 ± 8.4 minutes, respectively. Recovery was considered good in all animals. CONCLUSIONS AND CLINICAL RELEVANCE: Dexmedetomidine-butorphanol-midazolam combination provided reliable sedation and adequate muscle relaxation in L. catta. Alfaxalone proved to be a useful drug for induction and maintenance of anaesthesia and might be considered an option for injectable anaesthesia in lemurs.


Assuntos
Anestesia Intravenosa/veterinária , Anestésicos Combinados/administração & dosagem , Anestésicos , Butorfanol/administração & dosagem , Sedação Profunda/veterinária , Dexmedetomidina/administração & dosagem , Lemur/cirurgia , Midazolam/administração & dosagem , Pregnanodionas , Anestésicos/administração & dosagem , Animais , Sedação Profunda/métodos , Injeções Intramusculares/veterinária , Intubação Intratraqueal/veterinária , Masculino , Orquiectomia/veterinária , Pregnanodionas/administração & dosagem
17.
Curr Biol ; 28(8): 1306-1310.e2, 2018 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-29628372

RESUMO

Strong relationships exist between social connections and information transmission [1-9], where individuals' network position plays a key role in whether or not they acquire novel information [2, 3, 5, 6]. The relationships between social connections and information acquisition may be bidirectional if learning novel information, in addition to being influenced by it, influences network position. Individuals who acquire information quickly and use it frequently may receive more affiliative behaviors [10, 11] and may thus have a central network position. However, the potential influence of learning on network centrality has not been theoretically or empirically addressed. To bridge this epistemic gap, we investigated whether ring-tailed lemurs' (Lemur catta) centrality in affiliation networks changed after they learned how to solve a novel foraging task. Lemurs who had frequently initiated interactions and approached conspecifics before the learning experiment were more likely to observe and learn the task solution. Comparing social networks before and after the learning experiment revealed that the frequently observed lemurs received more affiliative behaviors than they did before-they became more central after the experiment. This change persisted even after the task was removed and was not caused by the observed lemurs initiating more affiliative behaviors. Consequently, quantifying received and initiated interactions separately provides unique insights into the relationships between learning and centrality. While the factors that influence network position are not fully understood, our results suggest that individual differences in learning and becoming successful can play a major role in social centrality, especially when learning from others is advantageous.


Assuntos
Lemur/psicologia , Comportamento Social , Rede Social , Animais , Comportamento Animal/fisiologia , Feminino , Conhecimento , Aprendizagem/fisiologia , Masculino
18.
J Comp Pathol ; 157(2-3): 85-89, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28942309

RESUMO

Naturally occurring mammary tumours are uncommon in prosimians. A 20-year-old female ring-tailed lemur (Lemur catta) developed bilateral enlargement of the mammary glands. Surgical removal revealed that both masses were comprised of multiple nodules and cystic areas that entirely replaced the normal glands. Histologically, a benign neoplastic biphasic cellular proliferation, composed of luminal-epithelial and basal-myoepithelial components, was identified. Immunohistochemical analysis for expression of cytokeratin (CK) AE1/AE3, CK7, CK5 + 8, CK14, vimentin, p63 and 14-3-3σ highlighted the biphasic nature of the neoplasm. A low mitotic count, low Ki67 labelling index, expression of oestrogen receptor-α, lack of expression of human epidermal growth factor receptor and a 3-year disease-free period without recurrence supported the benign nature of the tumour. Macroscopically, histologically and immunohistochemically this neoplasm resembled benign adenomyoepithelioma of the breast in women. This is the first complete report of a naturally occurring mammary tumour in a ring-tailed lemur.


Assuntos
Adenomioepitelioma/veterinária , Lemur , Neoplasias Mamárias Animais/patologia , Animais , Feminino
19.
Vet Parasitol ; 241: 1-4, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28579023

RESUMO

Here we describe fatal pulmonary cysticercosis caused by Cysticercus longicollis, the larval stage of Taenia crassiceps in a 15-year-old female ring-tailed lemur (Lemur catta) from Sarajevo Zoo. After sudden death, the lemur was subjected to necropsy and large multicystic structure, subdivided with fibrous septa and filled with numerous translucent, oval to ellipsoid bladder-like cysts (cysticerci), almost completely replacing right lung lobe was observed. In addition, numerous free and encysted cysticerci were found in the thoracic cavity. Histopathology revealed connective tissue outlined cavities that compress lung parenchyma. Each cavity contained several thin walled cysticerci with single inverted protoscolex, one or more suckers and rostelum with two rows of hooks. In many of the cysticerci one or several exogenous buds of daughter cysticerci were observed. Based on morphology and microscopic appearance the parasite was identified as C. longicollis. Subsequent molecular analysis and sequencing confirmed presumptive diagnosis. To our knowledge, this case represents the first report of T. crassiceps and cysticercosis caused by C. longicollis in Bosnia and Herzegovina.


Assuntos
Cisticercose/veterinária , Cysticercus/classificação , Lemur/parasitologia , Animais , Animais de Zoológico , Cisticercose/patologia , Evolução Fatal , Feminino
20.
Curr Zool ; 63(4): 467-475, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29492006

RESUMO

Vocal individuality is widespread in social animals. Individual variation in vocalizations is a prerequisite for discriminating among conspecifics and may have facilitated the evolution of large complex societies. Ring-tailed lemurs Lemur catta live in relatively large social groups, have conspicuous vocal repertoires, and their species-specific utterances can be interpreted in light of source-filter theory of vocal production. Indeed, their utterances allow individual discrimination and even recognition thanks to the resonance frequencies of the vocal tract. The purpose of this study is to determine which distinctive vocal features can be derived from the morphology of the upper vocal tract. To accomplish this, we built computational models derived from anatomical measurements collected on lemur cadavers and compared the results with the spectrographic output of vocalizations recorded from ex situ live individuals. Our results demonstrate that the morphological variation of the ring-tailed lemur vocal tract explains individual distinctiveness of their species-specific utterances. We also provide further evidence that vocal tract modeling is a powerful tool for studying the vocal output of non-human primates.

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