RESUMO
Emotions are omnipresent in many animals' lives. It is a complex concept that encompasses physiological, subjective, behavioural and cognitive aspects. While the complex relationship between emotion and cognition has been well studied in humans and in some nonhuman primates, it remains rather unexplored for other nonhuman primate species, such as lemurs. In our study, we evaluated the performance of N = 48 grey mouse lemurs (Microcebus murinus) in a discrimination learning task using visual emotional stimuli. We tested whether the type of visual stimulus (positive, negative or neutral) influenced the cognitive performance of mouse lemurs. Individuals had to learn to discriminate between two platforms according to the associated visual stimuli and to jump to the target platform (leading to a reward). Our main finding was that emotional stimuli, whether positive or negative in valence, impaired cognitive performance when used as a target. Specifically, the lowest success rate occurred when the target was associated with the emotional stimuli, and the highest success rate occurred when it was associated with neutral stimuli. Our results show a similar pattern to that found in other primate species and support the adaptive role of emotion. Our results also support that individual differences could be a factor impacting the relation between emotion and cognition. This study is the first to explore how emotions interfere with the cognitive abilities of a lemur species and highlights the importance of acknowledging emotion in mouse lemurs as well as studying the emotion-cognition interaction in a wider range of primate species.
Assuntos
Cheirogaleidae , Cognição , Aprendizagem por Discriminação , Emoções , Animais , Cheirogaleidae/fisiologia , Cheirogaleidae/psicologia , Masculino , Feminino , Estimulação LuminosaRESUMO
We diagnosed Mycobacterium tuberculosis in captive lemurs and a fossa in Antananarivo, Madagascar. We noted clinical signs in the animals and found characteristic lesions during necropsy. The source of infection remains unknown. Our results illustrate the potential for reverse zoonotic infections and intraspecies transmission of tuberculosis in captive wildlife.
Assuntos
Lemur , Mycobacterium tuberculosis , Tuberculose , Animais , Madagáscar/epidemiologia , Tuberculose/veterinária , Animais Selvagens , Animais de ZoológicoRESUMO
Red Book Challenge Conservation Education Madagascar is a small-scale, arts-based, conservation education initiative founded in 2012 by two Lemur catta researchers working in the Berenty Reserve and incorporated as a nonprofit organization in 2022. The target demographic is children and adults living in Southern Madagascar. The Red Book Challenge program initially consisted of providing supplementary conservation education through classroom visits at the elementary schools in Berenty village. The school children created small conservation booklets with red covers, giving the project its name. Today, the program has expanded to include the village of Besakoa Ambany and the city of Fort Dauphin, while remaining a small-scale program. To date, the Red Book Challenge has completed seven outreach projects aimed at generating goodwill in the local community, community development, and conservation education. This retrospective analysis functions as a formative evaluation of the feasibility of future projects. This paper will focus on four projects that fall under the category of conservation education: (1) Using films to promote conservation topics (2) field trips to observe lemurs (3) a Malagasy-run conservation club, and (4) a coloring book. These projects have been funded through small grants from the International Conservation Fund of Canada, and private donations. This paper includes the Red Book Challenge's history, results from the participant surveys, and the successes and failures in each stage of our work. Six shifts in thinking occurred: (1) use of Malagasy talent to create educational conservation films (2) more formal assessment before and after field trips (3) improvement of recruitment, training and supervision of staff to keep the conservation club self-sufficient (4) enlistment of Malagasy illustrators and adaptation of environmentally friendly printing practices for the coloring books (5) disseminate study outcomes to international community though publication (6) reframe the program from spare-time volunteer work to full-time research work.
Assuntos
Lemur , Lemuridae , Strepsirhini , Animais , Madagáscar , Estudos RetrospectivosRESUMO
Microsatellites have been a workhorse of evolutionary genetic studies for decades and are still commonly in use for estimating signatures of genetic diversity at the population and species level across a multitude of taxa. Yet, the very high mutation rate of these loci is a double-edged sword, conferring great sensitivity at shallow levels of analysis (e.g. paternity analysis) but yielding considerable uncertainty for deeper evolutionary comparisons. For the present study, we used reduced representation genome-wide data (restriction site-associated DNA sequencing (RADseq)) to test for patterns of interspecific hybridization previously characterized using microsatellite data in a contact zone between two closely related mouse lemur species in Madagascar (Microcebus murinus and Microcebus griseorufus). We revisit this system by examining populations in, near, and far from the contact zone, including many of the same individuals that had previously been identified as hybrids with microsatellite data. Surprisingly, we find no evidence for admixed nuclear ancestry. Instead, re-analyses of microsatellite data and simulations suggest that previously inferred hybrids were false positives and that the program NewHybrids can be particularly sensitive to erroneously inferring hybrid ancestry. Combined with results from coalescent-based analyses and evidence for local syntopic co-occurrence, we conclude that the two mouse lemur species are in fact completely reproductively isolated, thus providing a new understanding of the evolutionary rate whereby reproductive isolation can be achieved in a primate.
Assuntos
Cheirogaleidae , Lemur , Animais , Evolução Biológica , Cheirogaleidae/genética , Hibridização Genética , Lemur/genética , Madagáscar , Repetições de Microssatélites , Análise de Sequência de DNARESUMO
Madagascar's lemurs are threatened by forest loss, fragmentation, and degradation. Many species use flexible behaviors to survive in degraded habitat, but their ability to persist in very small areas may be limited. Insular lemurs, like those found on Nosy Be, an island off the northwestern coast of Madagascar, are at heightened risk of sudden population declines and extirpation. Nosy Be is home to two Critically Endangered species-the endemic Nosy Be sportive lemur (Lepilemur tymerlachsoni) and Claire's mouse lemur (Microcebus mamiratra)-as well as the Endangered black lemur (Eulemur macaco). Most of the remaining forest on Nosy Be is protected by the 862-ha Lokobe National Park. To document how Nosy Be lemurs use their restricted habitat, we conducted vegetation and reconnaissance surveys on 53 transects in and around Lokobe. We collected data on tree size, canopy cover, understory visibility, and elevation for 248 lemur sightings. We used a spatially explicit, multi-species occupancy model to investigate which forest-structure variables are important to lemurs. Our results represent some of the first data on habitat use by insular lemurs. Black lemurs preferred significantly larger trees and areas with less dense understory. They also occurred significantly less outside of Lokobe National Park, even when accounting for sampling effort and geography. The distributions of the sportive and mouse lemurs were not related to the forest structure variables we documented, but they did negatively predict each other-perhaps because their habitat requirements differ. These results also underscore the importance of the national park to protecting the black lemur population on Nosy Be and raise questions about what factors do influence the distribution of Nosy Be's smaller lemurs. Close monitoring is needed to prevent these populations and the ecosystem services they provide from disappearing, as have other island lemurs.
Assuntos
Lemur , Lemuridae , Animais , Cheirogaleidae , Ecossistema , Madagáscar , ÁrvoresRESUMO
Madagascar is home to many threatened and endemic primate species, yet this island has seen dramatic declines in lemur habitat due to forest loss. This forest loss has resulted in an increasingly fragmented forest landscape, with fragments isolated from each other by grasslands (i.e., matrix). The grassland matrix is not entirely homogeneous containing matrix elements such as isolated trees and shrubs and linear features such as drainage lines. Because most lemurs are predominantly arboreal, they may preferentially use matrix elements to facilitate dispersal between fragments for access to mates or reduce feeding competition, allowing gene flow between fragments of habitat. Therefore, it is important to understand to what degree they use the matrix. We investigated matrix use in two mouse lemurs, the grey mouse lemur (Microcebus murinus) and the golden-brown mouse lemur (Microcebus ravelobensis) in a fragmented landscape in northwest Madagascar. We tested the predictions that: (1) lemurs use matrix less often than forest fragments, (2) if they use the matrix, then they will preferentially use matrix elements compared to grassland, and (3) M. murinus will disperse into the matrix further than M. ravelobensis. In 2011, we visually surveyed line transects in four areas containing matrix elements and four adjacent forest fragments during nocturnal walks. In 2017, we set up traplines in four areas of the matrix containing matrix elements, three areas that were grassland, and six traplines in adjacent fragments. We compared the relative abundance of mouse lemurs in matrix transects to fragmented forest transects, and the relative abundance of captured lemurs in matrix elements, grassland, and fragment traplines. We found that encounter rates of mouse lemurs did not significantly differ between the matrix and fragmented forest transects or traplines. Our sample size was too low to determine if the mean distance from the forest was greater for either Microcebus spp. Our study highlights that mouse lemurs do use matrix elements and there may be interspecific differences in use. Further research is needed to confirm species-specific matrix use, why mouse lemurs use matrix, and how much matrix elements facilitate movement for each species in fragmented landscapes.
Assuntos
Cheirogaleidae/fisiologia , Ecossistema , Animais , Comportamento Animal , Florestas , Pradaria , MadagáscarRESUMO
Traditional socio-ecological models consider that folivorous primates experience limited feeding competition due to the low quality, high abundance, and even distribution of leaves. Evidence from several folivorous species that experience similar constraints to frugivores does not support this hypothesis. The sympatric lemur genera Avahi (Indriidae) and Lepilemur (Lepilemuridae) are good models to understand how food availability constrains folivores since they are both nocturnal, folivorous, and have a comparable body mass. Here we investigate how two nocturnal folivorous primates, Avahi meridionalis and Lepilemur fleuretae, living in the lowland rain forest of Tsitongambarika, South-East Madagascar, partition their dietary niche and are influenced by seasonality of young leaves. To account for food availability, we collected annual phenological data on 769 trees from 200 species. We also collected behavioural data on 5 individuals per lemur species from August 2015 to July 2016 via continuous focal sampling. We found the phenological profile to be seasonal with peaks of leaf flushing, flowering, and fruiting occurring in the austral summer. The two species showed limited dietary overlap (37% rich period, 6% lean period), and A. meridionalis showed higher feeding time and longer daily distances travelled during the rich period. Lepilemur fleuretae showed a dietary shift during the lean period, relying more on mature leaves (73.3% during the lean period, 13.5% during the rich period) but maintaining similar activity levels between seasons. The time spent feeding on food items by A. meridionalis was positively correlated with the nitrogen content and negatively correlated with polyphenols during the rich period. We highlighted a clear effect of the seasonality of young leaves on the diet, nutritional content, activity patterns, and daily distances travelled by two folivorous species, which can be linked to nutrient balancing and time-minimising versus energy-maximising strategies.
Assuntos
Dieta/veterinária , Folhas de Planta , Strepsirhini/fisiologia , Animais , Ecossistema , Feminino , Madagáscar , Masculino , Folhas de Planta/crescimento & desenvolvimento , Estações do Ano , Especificidade da EspécieRESUMO
OBJECTIVES: Phylogenies consistently group the folivorous Lepilemur species with the small-bodied insectivorous-frugivorous cheirogaleids. Juvenile lepilemurs and adult cheirogaleids share allometries in most aspects of skull morphology, except the palate. We investigated potential influences on palate shape in these taxa and several outgroups using geometric morphometrics. MATERIALS AND METHODS: Our sample included representatives of four extant strepsirrhine families, Cheirogaleidae (including Lepilemurinae), Lemuridae, Indriidae, and Galagidae, and one subfossil Megaladapis. Our dataset comprised 32 landmarks collected from 397 specimens representing 15 genera and 28 species, and was analyzed using generalized procrustes analyses and between group principal component analysis. We explored the influence of size, phylogeny, diet, and the propagation of loud vocalizations on palate shape. RESULTS: While congeneric species clustered within the morphospace, the phylomorphospace did not mirror molecular phylogenetic hypotheses of higher-order relationships. Four palate forms were distinguished within the Cheirogaleidae. Diet, strongly linked to body size, had the single greatest influence on palate shape. The production of long-distance advertisement calls was most often associated with positive scores on the PC1 axis. DISCUSSION: Our results suggest that the extensive variation in palate shape among Cheirogaleidae is related to dietary shifts that accompanied changes in body size during the clade's radiation. Molecular phylogenies indicate that cheirogaleid diversification involved repeated dwarfing events, which in turn drove dietary shifts from ancestral folivory-frugivory to frugivory, gummivory, and faunivory in the descendant species. The elongated Lepilemur palate is probably related to accelerated eruption of the cheek teeth to render juveniles competent to shear leaves upon weaning.
Assuntos
Comportamento Alimentar/fisiologia , Palato/anatomia & histologia , Strepsirhini/anatomia & histologia , Strepsirhini/classificação , Animais , Antropologia Física , Antropometria , Evolução Biológica , Tamanho Corporal/fisiologia , Cheirogaleidae/anatomia & histologia , Cheirogaleidae/classificação , Dieta , Feminino , Fósseis , Masculino , FilogeniaRESUMO
The rise in research investigating fragmentation and its impact on primates and other taxa reflects the growing presence of fragmented landscapes themselves. Although numerous studies report the negative effects of fragmentation on biodiversity, it is difficult to generalize responses to fragmentation for specific taxonomic groups, such as non-human primates, when studies have not employed a definitive concept of fragmentation or fragments themselves. Madagascar's high degree of fragmentation, wealth of endemic taxa, and extensive history of ecological research provide the opportunity to compare fragmentation studies across similar contexts. We conducted a literature search of peer-reviewed articles on fragmentation in Madagascar to characterize its trends. A total of 70 articles, 46 of which concentrated on lemurs, tested the impacts of fragmentation on Malagasy taxa, while additional sources conducted research in one or more fragments without testing its effects (n = 112 total, 79 on lemurs). Studies on lemurs most frequently tested fragmentation's impacts on genetics and biodiversity metrics (n = 16 and 15 studies, respectively), although health, modeling, behavioral, and cross-disciplinary techniques were also reported. Responses to fragmentation were reported for 49 lemur species, with most studies concentrated in eastern Madagascar (87%). Although there was variation in the metrics reported in studies testing the effects of fragmentation on Malagasy species, the most common measures were fragment area, isolation, or comparison to a control site. Landscape-scale approaches and examination of fragmentation per se were rarely employed. Characterizing trends of fragmentation research in Madagascar emphasizes the challenges of documenting fragmentation's effects while highlighting the benefits of research within fragmented landscapes, particularly when combined with consideration for how the matrix within human-modified landscapes may impact primate populations.
Assuntos
Ecossistema , Florestas , Lemuridae , Animais , Biodiversidade , MadagáscarRESUMO
Due to the impact of anthropogenic activities on forest extent and integrity across Madagascar, it is increasingly necessary to assess how endangered lemur populations inhabiting human-dominated forest fragments can effectively sustain themselves ecologically. Our research addresses this concern by exploring how the distribution patterns of a small population of crowned lemurs (Eulemur coronatus), occupying a degraded forest fragment at Oronjia Forest New Protected Area in northern Madagascar, are impacted by the availability of key ecological and anthropogenic factors. We hypothesize that the distribution of E. coronatus within the fragment is limited by the availability of critical ecological resources and conditions and the intensity of anthropogenic features and activities. To examine this, we used MaxEnt to develop a species distribution model using presence-only occurrence records and 10 independent background covariates detailing the site's ecological and anthropogenic aspects. The results indicate that the realized distribution patterns of E. coronatus within human-dominated forest fragments are strongly associated with sections of forest that contain sparsely and sporadically distributed resources, such as freshwater and continuous hardwood vegetation. We conclude that the distribution of E. coronatus at Oronjia is shaped by their need to maximize foraging opportunities in a degraded forest landscape where they are subject to both environmental and anthropogenic stressors.
Assuntos
Ecossistema , Florestas , Lemuridae , Distribuição Animal , Conservação dos Recursos Naturais , Água Doce , Atividades Humanas , MadagáscarRESUMO
Previous primate research has demonstrated social learning related to accepting novel foods, but little evidence suggests social learning of food avoidance. Ring-tailed lemurs (Lemur catta)have been observed to shake their heads rapidly in response to sour and bitter stimuli. This study investigated whether this head-shaking behavior may have a social function. The experiment presented a performing lemur with two items of the same type of fruit, one of which had been manipulated to take on a sour flavor, and the other which was not manipulated and served as a control. The performer could taste each of the stimuli while an observing lemur had the opportunity to watch the performer's behavior from an adjacent enclosure. The observer was then presented with two stimuli with the same qualities. This study evaluated whether a preceding head-shaking reaction by the performer improved the success rate of the observer avoiding bitter stimuli to greater than chance. Our results reveal that following a head shake by the performer in response to the sour stimuli, observer avoidance of sour stimuli was statistically greater than chance, indicating that there may be social influences on food avoidance in this species. Further research should focus on confirming this effect and characterizing the full set of socially influential food reaction behaviors.
Assuntos
Comportamento de Escolha , Lemur/fisiologia , Comportamento Social , Animais , Ácido Cítrico , Citrullus , Frutas , Aprendizagem , PaladarRESUMO
Cathemeral primates perform significant amounts of activity during the daylight and dark portions of the 24-h cycle. Most brown lemurs have been reported to be cathemeral. A previous study reported that brown lemurs in Ankarafantsika National Park (ANP) shift their activity pattern from being cathemeral in the dry season to being diurnal in the wet season. From July 2015 to March 2016, we collected data on active behaviour of brown lemurs over 46 full-day and 33 full-night observations, distributed evenly between the dry and wet seasons. This study examined the abiotic factors that potentially allow this seasonal shift from cathemeral to diurnal activity. We analysed the effects of day length (time from sunrise to sunset), nocturnal luminosity, and climatic factors on the diurnal and nocturnal activities of the brown lemurs in ANP using generalized linear mixed models. We found that the brown lemurs were cathemeral regardless of season. Their diurnal activity increased with increasing day length and at high humidity, but decreased on days of high temperature and low lunar luminosity. Their nocturnal activity increased with decreasing day length, during bright nights, at low temperature, and at low humidity. Their diurnal and nocturnal activities decreased during heavy rainfall. These data indicate that the photoperiodic variation entrained their activity rhythm. Bright nights may provide better visibility, advantageous for the detection of predators and food, although it may increase exposure to predators. The modification of activity level with temperature variation can be a behavioural thermoregulation. The high humidity during the wet season probably reduced evaporative cooling, inducing increased body temperature and stimulating water foraging as a potential response to dehydration and active heat dissipation. Investigation on physiological responses to environmental factors is needed to fully understand cathemerality in lemurs. These findings emphasize the flexibility of diurnal and nocturnal activity level of brown lemurs according to the great seasonal variation in tropical dry forests.
Assuntos
Ritmo Circadiano , Lemuridae/fisiologia , Fotoperíodo , Tempo (Meteorologia) , Animais , Feminino , Florestas , Madagáscar , Masculino , Estações do AnoRESUMO
Primate loud calls often encode information relating to species identity. A previous study of loud calls of fork-marked lemurs (genus Phaner) indicated differences among the calls of four populations that have been accorded species status on the grounds of morphology and biogeography: Phaner electromontis, P. parienti, P. furciferand P. pallescens. I made field recordings of two typical calls (kiu and kea) emitted by all four populations and conducted playback experiments in Kirindy Forest to investigate whether free-ranging P. pallescensindividuals could discriminate the loud calls of their own species from those of others. Individual response behaviour, social context and call type used in playback were analysed using a goodness-of-fit G test. The effect of specific call identity was significant, while the effects of context and call type were not. Individuals responded to P. pallescens calls by approaching the speaker, but not to the calls of other populations. P. pallescens individuals appear to be capable of distinguishing the loud calls of their conspecifics, but the fact that the habitat structure of the sites of recording and playback of P. pallescenscalls was similar sounds a note of caution. Future studies should repeat the experiments with the other populations of fork-marked lemurs.
Assuntos
Cheirogaleidae/fisiologia , Vocalização Animal , Animais , Feminino , Madagáscar , MasculinoRESUMO
Rarely observed in mammals, female dominance is documented in several of Madagascar's lemurs. Although dominance affects many aspects of primates' lives, studies have largely focused on dyadic agonistic interactions to characterise relationships. We explored the power structure of three diademed sifaka groups (Propithecus diadema) at Tsinjoarivo during the lean season (July-August, 325 h) using social behaviours, group leadership, displacements and feeding outcomes. Two groups had a hierarchy dominated by the breeding female, while the highest rank was held by the breeding male in the third; in dyadic interactions, breeding females dominated males in all groups. Inconsistencies in hierarchies suggest that groups vary, with rank related to kinship ties of breeders. Aggression and grooming were rare; adult females received aggression at lower frequencies than males. Group movements were led more by females and followed more by males, and female feeding priority was evident in displacements during feeding. However, males and females did not differ in feeding outcomes, as expected (particularly in the lean season) if female dominance (and/or male deference) serves to ensure better access for females. This unexpected pattern (female dominance despite rare aggression, clear female leadership and displacement, yet no observable benefit in grooming or feeding outcomes) defies easy explanation, and reinforces the fact that studies examining female power in lemurs should take a multifaceted approach. Further study is needed to understand this pattern, the physiological and reproductive consequences of female dominance (e.g. detecting subtler variation in food quality or intake rates) and exactly how (and when) the benefits of female dominance are manifested.
Assuntos
Indriidae/psicologia , Predomínio Social , Animais , Feminino , Asseio Animal , Madagáscar , Masculino , Fatores SexuaisRESUMO
The recognition that much biodiversity exists outside protected areas is driving research to understand how animals survive in anthropogenic landscapes. In Madagascar, cacao (Theobroma cacao) is grown under a mix of native and exotic shade trees, and this study sought to understand whether lemurs were present in these agroecosystems. Between November 2016 and March 2017, discussions with farmers, nocturnal reconnaissance surveys and camera traps were used to confirm the presence of lemurs in the Cokafa and Mangabe plantations near Ambanja, north-west Madagascar. Four species of lemur were encountered in nocturnal surveys: Mirza zaza, Phaner parienti, Microcebussp. and Cheirogaleussp. with encounter rates of 1.2, 0.4, 0.4 and 0.3 individuals/km, respectively. The presence of Lepilemur dorsalis was confirmed by camera trap. This is the first time lemurs have been studied in cacao plantations, and understanding how these threatened animals use anthropogenic landscapes is vital for their conservation.
Assuntos
Biodiversidade , Cacau , Cheirogaleidae , Conservação dos Recursos Naturais , Lemuridae , Animais , Madagáscar , Densidade Demográfica , ÁrvoresRESUMO
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/veterináriaRESUMO
Yersinia enterocolitica (YE) bioserotype 1B/O:8 (YE 1B/O:8) was identified in routine culture of a variety of zoo species housed at Omaha's Henry Doorly Zoo and Aquarium (OHDZA) from April to July 2011. Animal cases representing 12 species had YE detected from 34 cases during routine fecal monitoring and/or during postmortem examination: Coquerel's sifakas (Propithecus coquereli, two cases), black & white (BW) ruffed lemurs (Varecia variegata variegata, six cases), red ruffed lemurs (Varecia rubra, seven cases), white handed gibbon (Hylobates lar albimana, one case), black lemurs (Eulemur macaco, three cases), mongoose lemurs (Eulemur mongoz, two cases), African hunting dogs (Lycaon pictus, five cases), agile gibbons (Hylobates agilis, three cases), siamangs (Hylobates syndactylus, two cases), colobus monkey (Colobus angolensis palliates, one case), argus pheasant (Argusianus argus, one case), and orangutan (Pongo pygmaeus, one case). Most species were not symptomatic; however, three symptomatic cases in Coquerel's sifakas (two) and a white handed gibbon (one) showed clinical signs of diarrhea and lethargy that resulted in death for the Coquerel's sifakas. One unexpected death also occurred in a BW ruffed lemur. To the authors' knowledge, this is the first report of YE 1B/O:8 in such a large variety of zoo species. The source of the YE could not be identified, prompting the initiation of a diseases surveillance program to prevent further cases for the species that are sensitive to YE. To date, no additional cases have been identified, thus suggesting a single introduction of the YE 1B/O:8 strain into the zoo environment.
Assuntos
Carnívoros , Galliformes , Primatas , Yersiniose/veterinária , Yersinia enterocolitica/fisiologia , Doença Aguda/epidemiologia , Animais , Animais de Zoológico , Derrame de Bactérias , Nebraska/epidemiologia , Sorogrupo , Yersiniose/microbiologia , Yersiniose/mortalidade , Yersiniose/transmissão , Yersinia enterocolitica/genética , Yersinia enterocolitica/isolamento & purificaçãoRESUMO
Detecting the risk of infection and minimizing parasite exposure represent the first lines of host defence against parasites. Individuals differ in the expression of these behavioural defences, but causes of such variation have received little empirical attention. We therefore experimentally investigated the effects of several individual and environmental factors on the expression level of faecal avoidance in the context of feeding, drinking, sleeping and defecating in a wild primate population. We found a strong sex bias in the expression level of anti-parasite behaviours of grey mouse lemurs (Microcebus murinus), with only females strongly avoiding contaminated food, water and nests, and exhibiting selective defecation. Our results further suggest that individuals adapted their protective behaviours according to variation in intrinsic and ecological factors that may influence the cost-benefit balance of behavioural defences. Overall, individuals exhibited high consistency of investment in protective behaviours across behavioural contexts and time, suggesting that grey mouse lemurs exhibit different hygienic personalities. Finally, the global hygienic score was negatively correlated with faecal-orally transmitted parasite richness, suggesting that variation in behavioural defence has fitness consequences. We suggest that integrating inter-individual variation in behavioural defences in epidemiological studies should improve our ability to model disease spread within populations.
Assuntos
Aprendizagem da Esquiva , Cheirogaleidae/psicologia , Asseio Animal , Interações Hospedeiro-Parasita , Animais , Fezes , Feminino , Masculino , Personalidade , Fatores SexuaisRESUMO
Madagascar's lemurs display a diverse array of feeding strategies with complex relationships to seed dispersal mechanisms in Malagasy plants. Although these relationships have been explored previously on a case-by-case basis, we present here the first comprehensive analysis of lemuriform feeding, to our knowledge, and its hypothesized effects on seed dispersal and the long-term survival of Malagasy plant lineages. We used a molecular phylogenetic framework to examine the mode and tempo of diet evolution, and to quantify the associated morphological space occupied by Madagascar's lemurs, both extinct and extant. Using statistical models and morphometric analyses, we demonstrate that the extinction of large-bodied lemurs resulted in a significant reduction in functional morphological space associated with seed dispersal ability. These reductions carry potentially far-reaching consequences for Malagasy ecosystems, and we highlight large-seeded Malagasy plants that appear to be without extant animal dispersers. We also identify living lemurs that are endangered yet occupy unique and essential dispersal niches defined by our morphometric analyses.
Assuntos
Extinção Biológica , Florestas , Modelos Estatísticos , Dispersão de Sementes/fisiologia , Strepsirhini/fisiologia , Árvores/crescimento & desenvolvimento , Animais , Simulação por Computador , Madagáscar , Árvores/classificaçãoRESUMO
This article introduces the open-source Subject-Mediated Automatic Remote Testing Apparatus (SMARTA) for visual discrimination tasks, which aims to streamline and ease data collection, eliminate or reduce observer error, increase interobserver agreement, and automate data entry without the need for an internet connection. SMARTA is inexpensive and easy to build, and it can be modified to accommodate a variety of experimental designs. Here we describe the utility and functionality of SMARTA in a captive setting. We present the results from a case study of color vision in ruffed lemurs (Varecia spp.) at the Duke Lemur Center in Durham, North Carolina, in which we demonstrate SMARTA's utility for two-choice color discrimination tasks, as well as its ability to streamline and standardize data collection. We also include detailed instructions for constructing and implementing the fully integrated SMARTA touchscreen system.