Wildfires disproportionately affected jaguars in the Pantanal.

The Pantanal wetland harbours the second largest population of jaguars in the world. Alongside climate and land-use changes, the recent mega-fires in the Pantanal may pose a threat to the jaguars' long-term survival. To put these growing threats into perspective, we addressed the reach and intensity of fires that have affected jaguar conservation in the Pantanal ecoregion over the last 16 years. The 2020 fires were the most severe in the annual series, burned 31% of the Pantanal and affected 45% of the estimated jaguar population (87% of these in Brazil); 79% of the home range areas, and 54% of the protected areas within home ranges. Fires consumed core habitats and injured several jaguars, the Pantanal's apex predator. Displacement, hunger, dehydration, territorial defence, and lower fecundity are among the impacts that may affect the abundance of the species. These impacts are likely to affect other less mobile species and, therefore, the ecological stability of the region. A solution to prevent the recurrence of mega-fires lies in combating the anthropogenic causes that intensify drought conditions, such as implementing actions to protect springs, increasing the number and area of protected areas, regulating fire use, and allocating fire brigades before dry seasons.

Record-breaking wildfires in the world's largest continuous tropical wetland: Integrative fire management is urgently needed for both biodiversity and humans.

In the Brazilian Pantanal, wildfire occurrence has increased, reaching record highs of over 40,000 km2 in 2020. Smoke from wildfires worsened the situation of isolated, as well as urban communities, already under an increasing toll of COVID-19. Here we review the impacts and the possible causes of the 2020 mega-fires and recommend improvements for public policies and fire management in this wetland. We calculated the amount of area burnt annually since 2003 and describe patterns in precipitation and water level measurements of the Paraguay River. Our analyses revealed that the 2020 wildfires were historically unprecedented, as 43% of the area (over 17,200 km2) had not been burnt previously in the last two decades. The extent of area affected in 2020 represents a 376% increase compared to the annual average of the area burnt annually in the last two decades, double than the value in 2019. Potential factors responsible for this increase are (i) severe drought decreased water levels, (ii) the fire corridor was located in the Paraguay River flood zone, (iii) constraints on firefighters, (iv) insufficient fire prevention strategy and agency budget reductions, and (v) recent landscape changes. Climate and land use change will further increase the frequency of these extreme events. To make fire management more efficient and cost-effective, we recommend the implementation of an Integrated Fire Management program in the Pantanal. Stakeholders should use existing traditional, local ecological, and scientific knowledge to form a collective strategy with clear, achievable, measurable goals, considering the socio-ecological context. Permanent fire brigades, including indigenous members, should conduct year-round fire management. Communities should cooperate to create a collaborative network for wildfire prevention, the location and characteristics (including flammability) of infrastructures should be (re)planned in fire-prone environments considering and managing fire-catalysed transitions, and depending on the severity of wildfires. The 2020 wildfires were tackled in an ad-hoc fashion and prioritisation of areas for urgent financial investment, management, protection, and restoration is necessary to prevent this catastrophe from happening again.

NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics.

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data.

Puberty and oestral cycle length in captive female jaguars Panthera onca.

Habitat loss and fragmentation have been leading jaguars to constant conflicts with humans, and as a result, jaguar populations have been declining over the last decades. Captive breeding is often a tool for species conservation, and it is not different for jaguars. However, success is far from optimal due to the lack of basic knowledge about species' reproductive biology. In the present study, we assessed gonadal hormonal profiles of natural oestral cycles and puberty and compared our data to those of other wild felids. We collected faecal samples from two to seven times per week for 18 months from two adults and three pre-pubertal females. We defined baseline levels for progestins and oestrogens in order to estimate oestrous cycle length and age at puberty. We compared our data with 16 other species through generalized linear model, using weight and genus as two explanatory variables. Cycle length was 38.28 ± 2.52 days, ranging from 25 to 44 days, while sexual maturity was attained within 22 months. Due to our analysis of both hormonal and behavioural data, there is a variation between this research from other studies that employed only behavioural observations. Such difference may be caused by the absence of behavioural oestrous at the peri-pubertal period. When compared to wild felids of similar size, puberty and oestral cycle durations of the jaguar females fell within the same range. Our modelling showed that age at maturity was influenced mostly by size and only Leopardus partially explained the observed variation. Conversely, oestral cycle length did not differ among genera or size categories. Our study adds to the body literature in the reproductive endocrinology of wild felids, and because female gametes are more challenging to collect and preserve, a strong understanding on the female reproductive physiology is essential to assisted reproduction and wild population viability assessment.

Neotropical carnivores: a data set on carnivore distribution in the Neotropics

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non‐detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non‐governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peerreviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non‐detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio‐temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other largescale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data.

Comparison of semen samples collected from wild and captive jaguars (Panthera onca) by urethral catheterization after pharmacological induction.

This study was designed to evaluate the efficiency of medetomidine anesthesia for semen collection through urethral catheter in wild and captive jaguars. Six captive and five wild jaguars were chemically restrained with a combination of medetomidine (0.08-0.1 mg/kg) and ketamine (5 mg/kg). After medetomidine administration the urethra was catheterized using a urinary tomcat catheter (1 mm diameter × 130 mm length) to collect semen from all animals. By using this technique, we could collect an average of 347.2 µl of semen containing 2,635.2 sperm/ml. Forward progressive motility, sperm progressive motility, and sperm morphology analysis demonstrated that the methodology did not affect sperm quality. Thus, urethral catheterization after medetomidine administration is a practical and efficient method to collect high-quality semen from wild and captive jaguars; this will enable the development of reproductive assisted technologies for jaguars.

Detection of Leptospira spp. and Brucella abortus antibodies in free-living jaguars (Panthera onca) in two protected areas of northern Pantanal, Brazil.

This study aimed to assess the exposure of free-living jaguars (Panthera onca) to Leptospira spp. and Brucella abortus in two conservation units in the Pantanal of Mato Grosso, Brazil. The presence of antibodies in blood samples of eleven jaguars was investigated using autochthonous antigens isolated in Brazil added to reference antigen collection applied to diagnosis of leptospirosis by Microscopic Agglutination Test (MAT). The Rose Bengal test was applied for B. abortus antibodies. Two (18.2%) jaguars were seroreactive for the Leptospira spp. antigen and the serovar considered as most infective in both animals was a Brazilian isolate of serovar Canicola (L01). All jaguars were seronegative for B. abortus. These data indicate that the inclusion of autochthonous antigens in serological studies can significantly increase the number of reactive animals, as well as modify the epidemiological profile of Leptospira spp. infection.

Carrapatos (Acari: Ixodidae) em mamíferos silvestres do Parque Nacional da Serra da Canastra e arredores, Minas Gerais, Brasil / Ticks (Acari: Ixodidae) on wild mammals in the Serra da Canastra National Park and surrounding areas, Minas Gerais, Brazil

O presente estudo relata ixodídeos em mamíferos silvestres no Parque Nacional da Serra da Canastra e arredores, no estado de Minas Gerais, Brasil. De julho de 2005 a junho de 2014, foram coletadas 58 larvas, 133 ninfas e 43 carrapatos adultos em 40 eventos de captura de mamíferos de vida livre do Parque e arredores. Nos hospedeiros da ordem Carnivora, foram identificados Amblyomma ovale Koch, 1844, Amblyomma sculptum Berlese, 1888, Amblyomma tigrinum Koch, 1844, Dermacentor nitens Neumann, 1897 e Rhipicephalus microplus (Canestrini, 1888). Em hospedeiros da ordem Xenarthra, foram identificados espécimes de Amblyomma pseudoconcolor Aragão, 1908 e A. sculptum. Este estudo relata os primeiros registros dos ixodídeos D. nitens e R. microplus parasitando Lycalopex vetulus, e A. ovale em Leopardus tigrinus no país. Os achados do presente estudo indicam a proximidade entre os animais domésticos e silvestres causada pela expansão agropecuária no território brasileiro.

This research­­­­­ reports ticks on wild mammals from the Serra da Canastra National Park and surrounding areas, in Minas Gerais state, Brazil. From July 2005 to June 2014, 58 larvae, 133 nymphs and 43 adult ticks were collected in 40 capture events of free-living mammals at the Park and surrounding areas. The tick species Amblyomma ovale Koch, 1844, Amblyomma sculptum Berlese, 1888, Amblyomma tigrinum Koch, 1844, Dermacentor nitens Neumann, 1897, and Rhipicephalus microplus (Canestrini, 1888) were identified on hosts of the order Carnivora. Specimens of Amblyomma pseudoconcolor Aragão, 1908 and A. sculptum were identified on the hosts of the order Xenarthra. We provide the first records of D. nitens and R. microplus ticks parasitizing Lycalopex vetulus, and A. ovale on Leopardus tigrinus in Brazil. The findings of this research indicate the sharing of environment by domestic and wild animals caused by agricultural expansion in the Brazilian landscape.

Exposure of free-living jaguars to Toxoplasma gondii, Neospora caninum and Sarcocystis neurona in the Brazilian Pantanal.

Toxoplasma gondii, Neospora caninum and Sarcocystis neurona are related apicomplexan parasites that cause reproductive and neurological disorders in a wide range of domestic and wild animals. In the present study, the immunofluorescence antibody test (IFAT) was used to investigate the presence of antibodies against T. gondii, N. caninum and S. neurona in the sera of 11 free-living jaguars (Panthera onca) in two protected areas in the Pantanal region of Mato Grosso state, Brazil. Ten jaguars (90.9%) showed seropositivity for T. gondii, eight (72.7%) for S. neurona, and seven (63.6%) for N. caninum antigens. Our findings reveal exposure of jaguars to these related coccidian parasites and circulation of these pathogens in this wild ecosystem. To the best of our knowledge, this is the first serological detection of N. caninum and S. neurona in free-living jaguars.

Exposure of free-living jaguars to Toxoplasma gondii, Neospora caninum and Sarcocystis neurona in the Brazilian Pantanal / Exposição de onças-pintadas a Toxoplasma gondii, Neospora caninum e Sarcocystis neurona no Pantanal brasileiro

Toxoplasma gondii, Neospora caninum and Sarcocystis neurona are related apicomplexan parasites that cause reproductive and neurological disorders in a wide range of domestic and wild animals. In the present study, the immunofluorescence antibody test (IFAT) was used to investigate the presence of antibodies against T. gondii, N. caninum and S. neurona in the sera of 11 free-living jaguars (Panthera onca) in two protected areas in the Pantanal region of Mato Grosso state, Brazil. Ten jaguars (90.9%) showed seropositivity for T. gondii, eight (72.7%) for S. neurona, and seven (63.6%) for N. caninum antigens. Our findings reveal exposure of jaguars to these related coccidian parasites and circulation of these pathogens in this wild ecosystem. To the best of our knowledge, this is the first serological detection of N. caninum and S. neurona in free-living jaguars.

Toxoplasma gondii, Neospora caninum e Sarcocystis neurona são coccídios relacionados responsáveis por causar desordens reprodutivas e neurológicas em uma ampla variedade de animais domésticos e selvagens. No presente estudo, a Reação de Imunofluorescência Indireta (RIFI) foi utilizada para investigar a presença de anticorpos contra T. gondii, N. caninum e S.neurona em soros de 11 onças-pintadas de vida livre (Panthera onca), provenientes de duas áreas protegidas na região do Pantanal do Estado de Mato Grosso, Brasil. Dez (90,9%), sete (63,6%) e oito (72,7%) onças amostradas foram soropositivas para T. gondii, N. caninum e S. neurona, respectivamente. Os resultados indicam a exposição a esses coccídios relacionados entre as onças-pintadas e a circulação ambiental desses patógenos nesse ecossistema selvagem. Este é o primeiro relato da detecção sorológica de N. caninum e S. neurona em onças-pintadas de vida livre.

Identification of priority conservation areas and potential corridors for jaguars in the Caatinga biome, Brazil.

The jaguar, Panthera onca, is a top predator with the extant population found within the Brazilian Caatinga biome now known to be on the brink of extinction. Designing new conservation units and potential corridors are therefore crucial for the long-term survival of the species within the Caatinga biome. Thus, our aims were: 1) to recognize suitable areas for jaguar occurrence, 2) to delineate areas for jaguar conservation (PJCUs), 3) to design corridors among priority areas, and 4) to prioritize PJCUs. A total of 62 points records of jaguar occurrence and 10 potential predictors were analyzed in a GIS environment. A predictive distributional map was obtained using Species Distribution Modeling (SDM) as performed by the Maximum Entropy (Maxent) algorithm. Areas equal to or higher than the median suitability value of 0.595 were selected as of high suitability for jaguar occurrence and named as Priority Jaguar Conservation Units (PJCU). Ten PJCUs with sizes varying from 23.6 km2 to 4,311.0 km2 were identified. Afterwards, we combined the response curve, as generated by SDM, and expert opinions to create a permeability matrix and to identify least cost corridors and buffer zones between each PJCU pair. Connectivity corridors and buffer zone for jaguar movement included an area of 8.884,26 km2 and the total corridor length is about 160.94 km. Prioritizing criteria indicated the PJCU representing c.a. 68.61% of the total PJCU area (PJCU # 1) as of high priority for conservation and connectivity with others PJCUs (PJCUs # 4, 5 and 7) desirable for the long term survival of the species. In conclusion, by using the jaguar as a focal species and combining SDM and expert opinion we were able to create a valid framework for practical conservation actions at the Caatinga biome. The same approach could be used for the conservation of other carnivores.

Microbiota and anthropic interference on antimicrobial resistance profile of bacteria isolated from Brazilian maned-wolf (Chrysocyon brachyurus)

Both the study of Brazilian wild mammal fauna and the conditions that foster the preservation of endangered species, such as Brazilian Maned-wolf (Chrysocyon brachyurus), in wild life are of extreme importance. In order to study the resistance profile of microbiota bacterial colonizing Brazilian Maned-wolf, this work investigated samples from eight male captive and free roaming animals originating from different Brazilian geographical regions. Samples for microbiological purposes were collected with swabs and kept in appropriate transport medium. Using routine microbiological techniques, the isolated bacteria were tested toward antimicrobial drugs by the agar disk diffusion method. Results showed that all samples from wild animals were sensitive toward all drugs tested. Conversely, the resistance profile of bacteria isolated from captive animals varied among strains and animal body site location. Escherichia coli samples from prepuce, anus and ear showed multi-resistance toward at least four drugs, especially against erythromycin and tetracycline, followed by Proteus mirabilis and P. vulgaris strains isolated from anus and ear. Among Gram-positive bacteria, strains of coagulase-negative staphylococci showed multi-resistance mainly toward erythromycin and amoxicillin. The work discusses these findings and suggests that profile of multi-resistance bacteria from captive subjects may be attributed to direct contact with human or through lifestyle factors such as feeding, predation or contact of animals with urban animals such as birds, rodents, and insects from surrounding environments.

Microbiota and anthropic interference on antimicrobial resistance profile of bacteria isolated from Brazilian Maned-wolf (Chrysocyon brachyurus).

Both the study of Brazilian wild mammal fauna and the conditions that foster the preservation of endangered species, such as Brazilian Maned-wolf (Chrysocyon brachyurus), in wild life are of extreme importance. In order to study the resistance profile of microbiota bacterial colonizing Brazilian Maned-wolf, this work investigated samples from eight male captive and free roaming animals originating from different Brazilian geographical regions. Samples for microbiological purposes were collected with swabs and kept in appropriate transport medium. Using routine microbiological techniques, the isolated bacteria were tested toward antimicrobial drugs by the agar disk diffusion method. Results showed that all samples from wild animals were sensitive toward all drugs tested. Conversely, the resistance profile of bacteria isolated from captive animals varied among strains and animal body site location. Escherichia coli samples from prepuce, anus and ear showed multi-resistance toward at least four drugs, especially against erythromycin and tetracycline, followed by Proteus mirabilis and P. vulgaris strains isolated from anus and ear. Among Gram-positive bacteria, strains of coagulase-negative staphylococci showed multi-resistance mainly toward erythromycin and amoxicillin. The work discusses these findings and suggests that profile of multi-resistance bacteria from captive subjects may be attributed to direct contact with human or through lifestyle factors such as feeding, predation or contact of animals with urban animals such as birds, rodents, and insects from surrounding environments.

Detection of rabies virus antibodies in Brazilian free-ranging wild carnivores.

Rabies virus is a pathogen of major concern in free-ranging wild carnivores in several regions of the world, but little is known about its circulation in Brazilian wild carnivores. Sera from 211 free-ranging wild carnivores, captured from 2000 to 2006 in four locations of two Brazilian biomes (Pantanal and Cerrado), were tested for rabies antibodies. Twenty-six individuals (12.3%) had neutralizing antibody titers ≥0.10 IU/ml. The four sampled locations had antibody-positive animals, suggesting that Rabies virus circulates in all of these regions. Results underscore the risk posed by rabies for conservation of Brazilian carnivores and the possibility of the animals acting as reservoirs for the Rabies virus.

Padrão de atividade de onças pintadas (Panthera onca Linnaeus, 1758) mantidas em cativeiro: manejo e comportamento / Activity pattern of jaguars (Panthera onca Linnaeus, 1758) in captytity: handle and behavior

O estudo do comportamento e do bem estar de onças pintadas (Panthera onca) mantidas em cativeiro é vital para o seu manejo e reprodução. Avaliamos as condições dos recintos e o manejo de 9 animais em 5 zoológicos (SP), correlacionando-os com as observações obtidas pelo etograma que foi estabelecido visando avaliar a duração dos comportamentos destes animais. Os resultados corroboram a visão de que os tratadores dos zoológicos apresentaram uma percepção consonante com nossos achados. No entanto, as diferenças comportamentais observadas entre zoológicos, com distintos regimes de manejo, indicam que estudos futuros serão necessários. Este estudo propõe-se a contribuir para o desenvolvimento de um modelo para aplicação das técnicas de quantificação comportamental na avaliação dos diferentes efeitos das condições de manutenção sobre o padrão de atividade das espécies de felídeos mantidas em cativeiro

Padrão de atividade de onças pintadas (Panthera onca Linnaeus, 1758) mantidas em cativeiro: manejo e comportamento / Activity pattern of jaguars (Panthera onca Linnaeus, 1758) in captytity: handle and behavior

O estudo do comportamento e do bem estar de onças pintadas (Panthera onca) mantidas em cativeiro é vital para o seu manejo e reprodução. Avaliamos as condições dos recintos e o manejo de 9 animais em 5 zoológicos (SP), correlacionando-os com as observações obtidas pelo etograma que foi estabelecido visando avaliar a duração dos comportamentos destes animais. Os resultados corroboram a visão de que os tratadores dos zoológicos apresentaram uma percepção consonante com nossos achados. No entanto, as diferenças comportamentais observadas entre zoológicos, com distintos regimes de manejo, indicam que estudos futuros serão necessários. Este estudo propõe-se a contribuir para o desenvolvimento de um modelo para aplicação das técnicas de quantificação comportamental na avaliação dos diferentes efeitos das condições de manutenção sobre o padrão de atividade das espécies de felídeos mantidas em cativeiro (AU)

Seasonal variation in the endocrine-testicular function of captive jaguars (Panthera onca).

Captive adult male jaguars (Panthera onca) from two locations in southeast Brazil were studied to evaluate the effects of season on endocrine and testicular function. For assessment of testicular steroidogenic activity, androgen metabolite concentrations were measured in fecal samples collected one to three times per week over 14 ( n=14 ), 9 ( n=1 ) or 7 months ( n=1 ). To assess seasonality, data were grouped by season (summer: December-February; autumn: March-May; winter: June-August; spring: September-November). Additionally, samples collected in the dry season (March-August) were compared with those collected in the wet season (September-February). There were no differences ( P>0.05 ) in fecal androgen concentrations in samples collected in spring, summer, autumn, and winter ( 480.8+/-50.4 ng/g, 486.4+/-42.0 ng/g, 335.4+/-37.7 ng/g, and 418.6+/-40.4 ng/g dry feces). However, there were differences ( P<0.05 ) in fecal androgen concentrations between the dry and wet seasons ( 380.5+/-28.0 ng/g versus 483.9+/-32.3 ng/g dry feces). Sperm samples, collected from all males twice (approximately 6 months apart) were similar; mean (+/-S.E.M.) motility, concentration and morphology were 57.0 %4.5%, 6.3+/-2.4 x 10(6) ml(-1), and 60.8+/-3.1 %, respectively. In conclusion, androgen metabolite concentrations in the captive male jaguar were not affected by season, but there was a difference between the wet and dry periods. Further research is needed to verify these results.

Avaliaçäo da capacidade de penetraçäo de sêmen congelado de onça pintada (Panthera onca) em oócitos heterólogos / Penetration assay of frozen jaguar (Panthera onca) sperm in heterologous oocytes

A aplicaçäo de técnicas de reproduçäo assistida em espécies selvagens ameaçadas de extinçäo surge como método alternativo com o intuito de minimizar a diminuiçäo da variabilidade genética das populaçöes. Com o objetivo de determinar a fertilidade de onças pintadas (Panthera onca) mantidas em cativeiro e avaliar a eficácia dos meios de capacitaçäo espermática, foi realizado o ensaio de penetraçäo em oócitos de hamster livres de zona pelúcida. Para a realizaçäo do experimento, foi utilizado sêmen congelado de 3 animais do Bosque dos Jequitibás, Campinas/SP. Foram testadas 3 técnicas: Percoll, Swim-up e Swim-up + 1 hora em estufa de CO2 a 38§C, considerando como oócitos penetrados aqueles que apresentaram no seu interior a descondensaçäo da cabeça do espermatozóide. A média de penetraçöes da técnica Percoll (26,5 por cento) foi significativamente maior comparada à técnica Swim-up (8,1 por cento), sendo que näo houve penetraçäo utilizando a técnica Swim-up + 1 hora em estufa de CO2 a 38ºC (x2 = 19,93; p < 0,05). Analisando os resultados, concluímos que as técnicas Percoll e Swim-up foram eficientes para a realizaçäo do ensaio de penetraçäo, comprovando a capacidade de penetraçäo dos espermatozóides de onças pintadas (Panthera onca), pós-descongelamento, em oócitos de hamster livres de zona pelúcida. Porém, houve uma baixa porcentagem de penetraçäo, a qual pode estar associada ao elevado índice de espermatozóides morfologicamente anormais. Mais estudos devem ser conduzidos com a finalidade de avaliar a fertilidade destes animais e até que ponto a variabilidade da espécie pode estar comprometida

Reproductive characteristics of captive male jaguars (Panthera onca)

Ejaculate traits, testicular volume and plasma testosterone levels were determined once every two months for one year in 4 adult male jaguars (Panthera onca) housed at the Säo Paulo Zoo, SP, Brazil. Semen samples was collected by electroejaculation and analyzed for pH, total volume, motility (0-100 per cent), status (0-5), total spermatozoa count and morphology. Blood samples was obtained by cephalic venipuncture immediately before the onset of electroejaculation and stored at -20§C until assay of testosterone by RIA. Using a calliper, the length and width of each testis was measured and the values were combined to determine the testicular volume. Semen analyses demonstrated a high percentage of structurally abnormal sperm (mean = 51 per cent) and low rates of motility (50.6 per cent) and status (2.2). No correlation was found between semen traits, plasma testosterone and testicular volume (Spearman's test). No season variation was detected throughout the year for semen traits, plasma testosterone and testicular volume (p>0.05, Friedman's test). The results of this study suggest that the captive jaguars in Brazil are not seasonal, and that semen collections can be performed throughout the year without a perturbation in overall ejaculate quality. However, underlying causes of high percentages of structurally abnormal sperm, found in captive jaguars, need to be investigated mainly to improve semen quality