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Monica B. Martella - One of the best experts on this subject based on the ideXlab platform.
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Genetic identification of the ciliates from greater Rheas (Rhea americana) and lesser Rheas (Rhea pennata) as Balantioides coli
Parasitology Research, 2020Co-Authors: Juan José García-rodríguez, Joaquín Luis Navarro, Monica B. Martella, Rafael A. Martínez-díaz, Francisco Ponce-gordoAbstract:The ciliate species Balantioides coli can be cross-transmitted between humans and several animal species. Usually harmless, sometimes it can be pathogenic and cause the death of the host. In birds, B. coli has been confirmed in ostriches by genetic analysis, but the identification from South American greater Rheas ( Rhea americana ) and lesser Rheas ( Rhea pennata pennata ) is tentative. Since these species are reared for commercial purposes and for reintroduction into the wild, it is necessary to elucidate whether the ciliate from Rheas is B. coli to minimize health risks for humans and for other domestic and wild animals. Individual parasite cells are collected from Argentinean isolates of reared greater Rheas and of wild and reared lesser Rheas, and their ITS region was PCR amplified; the cloning products were sequenced and compared with sequences available in public databases. The results have shown that several sequence types are expressed at the same time in the parasite cells, and all correspond to B. coli , confirming the possibility of cross-transmission of the parasite between wild and reared South American Rheas and several mammal species and humans.
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distribution and concentration of maternal progesterone in the yolk of greater Rhea eggs Rhea americana
Journal of Experimental Zoology, 2017Co-Authors: N S Della Costa, Joaquín Luis Navarro, Juan Manuel Busso, R H Marin, Monica B. MartellaAbstract:Progesterone is the most concentrated maternal yolk steroid characterized to date in birds; however, no information about it is available in ratite eggs. We collected freshly laid eggs from zoo-housed Greater Rhea females (Rhea americana) bred under similar rearing conditions during two breeding seasons to characterize concentration and distribution of maternal yolk progesterone. After high-performance liquid chromatography analysis, yolk hormone was measured using a commercial electrochemiluminescence immunoassay. Progesterone concentrations were found to vary significantly among the yolk layers, supporting a follicular origin for this steroid in Greater Rhea eggs. Additionally, highly similar mean absolute yolk progesterone concentrations were detected between 2013 and 2015 breeding seasons (1,332.98 ± 82.59 and 1,313.59 ± 85.19 ng/g, respectively). These values are also comparable to those found in some domestic carinate species. Findings suggest that at population level, when rearing conditions are similar, mean absolute yolk maternal progesterone concentrations also appear bounded. Future research on the factors and mechanisms that regulate progesterone deposition in Greater Rhea eggs is needed to better understand whether its levels depend on different rearing conditions.
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influence of the rearing system on yolk corticosterone concentration in captive greater Rheas Rhea americana
Zoo Biology, 2016Co-Authors: N S Della Costa, Joaquín Luis Navarro, Juan Manuel Busso, Cristian Hansen, Raul Hector Marin, Monica B. MartellaAbstract:Many environmental conditions elevate plasma corticosterone in laying birds, leading to elevated hormone accumulation in the egg. We investigated whether maternal yolk corticosterone levels in Greater Rheas differ between fresh eggs collected from an intensive (IRS) and a semi-extensive (SRS) rearing system. After HPLC validation, yolk corticosterone was measured using a corticosterone (125) I radio-immunoassay kit. Results (mean ± SE) showed that eggs collected from the IRS exhibited a significantly higher corticosterone concentration than eggs from SRS (89.88 ± 8.93 vs. 45.41 ± 5.48 ng/g yolk, respectively). Our findings suggest that rearing conditions under an intensive scheme (e.g., small pens with bare ground, no direct foraging and handling) might be perceived as more stressful for Greater Rhea females than semi-extensive rearing conditions (e.g., low animal density distributed in extensive areas and direct foraging), which would result in the transfer of higher yolk corticosterone levels. A better understanding of environmental conditions and female traits that affect yolk corticosterone deposition provides a background for future studies concerning the roles of maternal corticosterone on offspring development. Zoo Biol. 35:246-250, 2016. © 2016 Wiley Periodicals, Inc.
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Gastrointestinal parasites in greater Rheas (Rhea americana) and lesser Rheas (Rhea pennata) from Argentina
Veterinary Parasitology, 2012Co-Authors: Rafael A. Martínez-díaz, Joaquín Luis Navarro, Monica B. Martella, Francisco Ponce-gordoAbstract:Abstract Few data exist on the parasites of ratites, especially from regions within their natural range. It is only recently that extensive studies on the parasites of ostriches ( Struthio camelus ) have been published, mainly from European countries where commercial farming has expanded. Two species of ratites are native in South America: the lesser Rhea also known as Darwin's Rhea ( Rhea pennata ) and the greater Rhea ( Rhea americana ). Both species are considered near threatened by the IUCN and are included in the CITES’ Appendices I and II, respectively. Parasitological studies have conservation implications, as they allow us to assess the risk of transmission of pathogens from farmed ratites to wild populations. In this study 92 faecal samples from greater Rheas and 55 faecal samples from lesser Rheas from different localities in Argentine were analyzed to determine their gastrointestinal parasites. In greater Rheas the protozoa ( Balantidium coli -like and Entamoeba spp.) and helminths ( Fasciola hepatica and Deletrocephalus spp.). The protozoa had not previously been cited as parasites of greater Rheas in South America. Cysts and/or trophozoites of B. coli -like were found in 16.3% of the samples, while the prevalence of the remaining parasites was below 10%. Lesser Rheas harbored the protozoa B. coli -like, Entamoeba spp. and Chilomastix spp. as well as F. hepatica and nematode eggs and larvae. B. coli -like cysts were found in 20.0% of the samples, while the prevalence of the other parasites remained below 5%. Some of them had not been cited as infecting lesser Rheas yet.
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Non-invasive monitoring of adrenocortical activity in Greater Rhea (Rhea americana) by measuring fecal glucocorticoid metabolites
Journal of Ornithology, 2011Co-Authors: Alvina Leche, Joaquín Luis Navarro, Juan Manuel Busso, Cristian Hansen, Raul H. Marin, Monica B. MartellaAbstract:The Greater Rhea (Rhea americana) is a near-threatened species. Wild populations are affected by human activities, such as illegal hunting, egg harvesting and conversion of natural habitats to croplands. An indicator of disturbances is the increase of the glucocorticoid corticosterone, a stress hormone that helps to cope with life-threatening situations. Here, we evaluate and characterize adrenocortical function in the Greater Rhea by validating the use of a radioimmunoassay (RIA) to assess fecal glucocorticoid metabolite concentrations, and by comparing the time course of plasma corticosterone and fecal immunoreactive glucocorticoid metabolite excretion. An adrenocorticotropic hormone (ACTH) challenge was performed and serial blood and fecal (cecal and rectal) samples were collected and analyzed by a corticosterone RIA. High-performance liquid chromatography (HPLC) was employed to characterize fecal immunoreactive glucocorticoid metabolites. HPLC analysis revealed the presence of two immunoreactive glucocorticoid metabolites in rectal and cecal Rhea feces. Greater Rheas responded to the ACTH challenge with a 30-fold increase in plasma corticosterone concentration 2 h post-injection, and a 30- to 40-fold increase in concentrations of glucocorticoid metabolites from rectal feces 4–6 h post-injection. In cecal feces, ACTH challenge produced an 11-fold increase. Therefore, collection of rectal feces would be more appropriated to ensure detection of minor increases in adrenocortical activity in this species. The adrenocortical response to ACTH found in Rhea was higher than what is usually observed in other birds and might be associated with their flightless condition and the use of running as an antipredator strategy.
Joaquín Luis Navarro - One of the best experts on this subject based on the ideXlab platform.
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Genetic identification of the ciliates from greater Rheas (Rhea americana) and lesser Rheas (Rhea pennata) as Balantioides coli
Parasitology Research, 2020Co-Authors: Juan José García-rodríguez, Joaquín Luis Navarro, Monica B. Martella, Rafael A. Martínez-díaz, Francisco Ponce-gordoAbstract:The ciliate species Balantioides coli can be cross-transmitted between humans and several animal species. Usually harmless, sometimes it can be pathogenic and cause the death of the host. In birds, B. coli has been confirmed in ostriches by genetic analysis, but the identification from South American greater Rheas ( Rhea americana ) and lesser Rheas ( Rhea pennata pennata ) is tentative. Since these species are reared for commercial purposes and for reintroduction into the wild, it is necessary to elucidate whether the ciliate from Rheas is B. coli to minimize health risks for humans and for other domestic and wild animals. Individual parasite cells are collected from Argentinean isolates of reared greater Rheas and of wild and reared lesser Rheas, and their ITS region was PCR amplified; the cloning products were sequenced and compared with sequences available in public databases. The results have shown that several sequence types are expressed at the same time in the parasite cells, and all correspond to B. coli , confirming the possibility of cross-transmission of the parasite between wild and reared South American Rheas and several mammal species and humans.
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distribution and concentration of maternal progesterone in the yolk of greater Rhea eggs Rhea americana
Journal of Experimental Zoology, 2017Co-Authors: N S Della Costa, Joaquín Luis Navarro, Juan Manuel Busso, R H Marin, Monica B. MartellaAbstract:Progesterone is the most concentrated maternal yolk steroid characterized to date in birds; however, no information about it is available in ratite eggs. We collected freshly laid eggs from zoo-housed Greater Rhea females (Rhea americana) bred under similar rearing conditions during two breeding seasons to characterize concentration and distribution of maternal yolk progesterone. After high-performance liquid chromatography analysis, yolk hormone was measured using a commercial electrochemiluminescence immunoassay. Progesterone concentrations were found to vary significantly among the yolk layers, supporting a follicular origin for this steroid in Greater Rhea eggs. Additionally, highly similar mean absolute yolk progesterone concentrations were detected between 2013 and 2015 breeding seasons (1,332.98 ± 82.59 and 1,313.59 ± 85.19 ng/g, respectively). These values are also comparable to those found in some domestic carinate species. Findings suggest that at population level, when rearing conditions are similar, mean absolute yolk maternal progesterone concentrations also appear bounded. Future research on the factors and mechanisms that regulate progesterone deposition in Greater Rhea eggs is needed to better understand whether its levels depend on different rearing conditions.
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influence of the rearing system on yolk corticosterone concentration in captive greater Rheas Rhea americana
Zoo Biology, 2016Co-Authors: N S Della Costa, Joaquín Luis Navarro, Juan Manuel Busso, Cristian Hansen, Raul Hector Marin, Monica B. MartellaAbstract:Many environmental conditions elevate plasma corticosterone in laying birds, leading to elevated hormone accumulation in the egg. We investigated whether maternal yolk corticosterone levels in Greater Rheas differ between fresh eggs collected from an intensive (IRS) and a semi-extensive (SRS) rearing system. After HPLC validation, yolk corticosterone was measured using a corticosterone (125) I radio-immunoassay kit. Results (mean ± SE) showed that eggs collected from the IRS exhibited a significantly higher corticosterone concentration than eggs from SRS (89.88 ± 8.93 vs. 45.41 ± 5.48 ng/g yolk, respectively). Our findings suggest that rearing conditions under an intensive scheme (e.g., small pens with bare ground, no direct foraging and handling) might be perceived as more stressful for Greater Rhea females than semi-extensive rearing conditions (e.g., low animal density distributed in extensive areas and direct foraging), which would result in the transfer of higher yolk corticosterone levels. A better understanding of environmental conditions and female traits that affect yolk corticosterone deposition provides a background for future studies concerning the roles of maternal corticosterone on offspring development. Zoo Biol. 35:246-250, 2016. © 2016 Wiley Periodicals, Inc.
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Gastrointestinal parasites in greater Rheas (Rhea americana) and lesser Rheas (Rhea pennata) from Argentina
Veterinary Parasitology, 2012Co-Authors: Rafael A. Martínez-díaz, Joaquín Luis Navarro, Monica B. Martella, Francisco Ponce-gordoAbstract:Abstract Few data exist on the parasites of ratites, especially from regions within their natural range. It is only recently that extensive studies on the parasites of ostriches ( Struthio camelus ) have been published, mainly from European countries where commercial farming has expanded. Two species of ratites are native in South America: the lesser Rhea also known as Darwin's Rhea ( Rhea pennata ) and the greater Rhea ( Rhea americana ). Both species are considered near threatened by the IUCN and are included in the CITES’ Appendices I and II, respectively. Parasitological studies have conservation implications, as they allow us to assess the risk of transmission of pathogens from farmed ratites to wild populations. In this study 92 faecal samples from greater Rheas and 55 faecal samples from lesser Rheas from different localities in Argentine were analyzed to determine their gastrointestinal parasites. In greater Rheas the protozoa ( Balantidium coli -like and Entamoeba spp.) and helminths ( Fasciola hepatica and Deletrocephalus spp.). The protozoa had not previously been cited as parasites of greater Rheas in South America. Cysts and/or trophozoites of B. coli -like were found in 16.3% of the samples, while the prevalence of the remaining parasites was below 10%. Lesser Rheas harbored the protozoa B. coli -like, Entamoeba spp. and Chilomastix spp. as well as F. hepatica and nematode eggs and larvae. B. coli -like cysts were found in 20.0% of the samples, while the prevalence of the other parasites remained below 5%. Some of them had not been cited as infecting lesser Rheas yet.
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Non-invasive monitoring of adrenocortical activity in Greater Rhea (Rhea americana) by measuring fecal glucocorticoid metabolites
Journal of Ornithology, 2011Co-Authors: Alvina Leche, Joaquín Luis Navarro, Juan Manuel Busso, Cristian Hansen, Raul H. Marin, Monica B. MartellaAbstract:The Greater Rhea (Rhea americana) is a near-threatened species. Wild populations are affected by human activities, such as illegal hunting, egg harvesting and conversion of natural habitats to croplands. An indicator of disturbances is the increase of the glucocorticoid corticosterone, a stress hormone that helps to cope with life-threatening situations. Here, we evaluate and characterize adrenocortical function in the Greater Rhea by validating the use of a radioimmunoassay (RIA) to assess fecal glucocorticoid metabolite concentrations, and by comparing the time course of plasma corticosterone and fecal immunoreactive glucocorticoid metabolite excretion. An adrenocorticotropic hormone (ACTH) challenge was performed and serial blood and fecal (cecal and rectal) samples were collected and analyzed by a corticosterone RIA. High-performance liquid chromatography (HPLC) was employed to characterize fecal immunoreactive glucocorticoid metabolites. HPLC analysis revealed the presence of two immunoreactive glucocorticoid metabolites in rectal and cecal Rhea feces. Greater Rheas responded to the ACTH challenge with a 30-fold increase in plasma corticosterone concentration 2 h post-injection, and a 30- to 40-fold increase in concentrations of glucocorticoid metabolites from rectal feces 4–6 h post-injection. In cecal feces, ACTH challenge produced an 11-fold increase. Therefore, collection of rectal feces would be more appropriated to ensure detection of minor increases in adrenocortical activity in this species. The adrenocortical response to ACTH found in Rhea was higher than what is usually observed in other birds and might be associated with their flightless condition and the use of running as an antipredator strategy.
Robert J. Young - One of the best experts on this subject based on the ideXlab platform.
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impacts of food based enrichment on behaviour and physiology of male greater Rheas Rhea americana rheidae aves
Papéis Avulsos de Zoologia, 2019Co-Authors: Marcia Fontes Figueiredo Lima, Cristiano Schetini De Azevedo, Robert J. Young, Priscila ViauAbstract:Distress can be defined as a biological response of an individual to long-term threats to its homeostasis and it should be avoided from an animal welfare perspective. High levels of stress hormones and the expression of abnormal behaviours are responses normally observed in distressed animals. Captive environments can provoke distress, especially when inappropriate stimuli are provided to the animals. The concomitant use of behavioural and non-invasive hormonal measures is a means to evaluate captive animal welfare. Environmental enrichment is a tool that can reduce distress and minimize the expression of abnormal behaviour in captive animals. The aim of this study was to evaluate greater Rheas’ responses (behavioral and hormonal) to food-based enrichment. Three birds from the Belo Horizonte Zoo, Brazil were studied. The study was divided into three phases (baseline, enrichment and post-enrichment): fruits scattered around the birds’ enclosure were used as enrichment. Behaviour and faecal sampling were undertaken in all phases of the study. Abnormal behaviours and faecal glucocorticoid metabolites (GCM) levels showed significant reduction during the environmental enrichment phase, and a significative positive correlation between GCM production and abnormal pacing was observed. From the results of this study, we conclude that the use of food as environmental enrichment should be encouraged because of its positive effects on animal welfare. Besides, studies with larger groups of greater Rheas, with individuals of both sexes, should also be encouraged to evaluate if the results found in this pilot study are consistent and can be generalized to the species.
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The fi shing Rhea: a new food item in the diet of wild greater Rheas (Rhea americana, Rheidae, Aves)
Revista Brasileira de Ornitologia - Brazilian Journal of Ornithology, 2013Co-Authors: Cristiano Schetini De Azevedo, Herlandes Penha Tinoco, João Bosco Ferraz, Robert J. YoungAbstract:The fi shing Rhea: a new food item in the diet of wild greater Rheas (Rhea americana, Rheidae, Aves)
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visitor influence on the behavior of captive greater Rheas Rhea americana rheidae aves
Journal of Applied Animal Welfare Science, 2012Co-Authors: Cristiano Schetini De Azevedo, Robert J. Young, Marcia Fontes Figueiredo Lima, Vitor Caetano Alves Da Silva, Marcos RodriguesAbstract:Visitors can affect and reduce the welfare of nonhuman animals. The Belo Horizonte Zoo, Brazil, had a group of greater Rheas intended for reintroduction to the wild. Because this group received public visitation, evaluating its effect on the birds' behavior and welfare was important. The study conducted 60 hr of behavioral observations: 30 with, and 30 without, visitors in front of the birds' enclosure. The study, conducted April–December 2009, collected data using scan sampling with instantaneous recording of behavior every minute. The study collected data on public behavior, visitor density, and time spent observing the birds. More than 4,000 persons visited the birds' enclosure: 9.86 s average time spent. Public behaviors most expressed were walking-watching-talking and stopped-watching-talking; visitors or not, greater Rheas' most expressed behaviors (inversed between treatments) were foraging and walking alert; defecating/urinating and other behaviors differed statistically between treatments. Walkin...
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visitor influence on the behavior of captive greater Rheas Rhea americana rheidae aves
Journal of Applied Animal Welfare Science, 2012Co-Authors: Cristiano Schetini De Azevedo, Robert J. Young, Marcia Fontes Figueiredo Lima, Vitor Caetano Alves Da Silva, Marcos RodriguesAbstract:Visitors can affect and reduce the welfare of nonhuman animals. The Belo Horizonte Zoo, Brazil, had a group of greater Rheas intended for reintroduction to the wild. Because this group received public visitation, evaluating its effect on the birds' behavior and welfare was important. The study conducted 60 hr of behavioral observations: 30 with, and 30 without, visitors in front of the birds' enclosure. The study, conducted April-December 2009, collected data using scan sampling with instantaneous recording of behavior every minute. The study collected data on public behavior, visitor density, and time spent observing the birds. More than 4,000 persons visited the birds' enclosure: 9.86 s average time spent. Public behaviors most expressed were walking-watching-talking and stopped-watching-talking; visitors or not, greater Rheas' most expressed behaviors (inversed between treatments) were foraging and walking alert; defecating/urinating and other behaviors differed statistically between treatments. Walking alert was most expressed in the presence of visitors; defecating/urinating and other behaviors were most expressed in their absence. Greater Rheas seemed to habituate to visitors. Birds' behaviors differed little in visitors' presence or absence.
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Failure of captive-born greater Rheas (Rhea americana, Rheidae, Aves) to discriminate between predator and nonpredator models
Acta Ethologica, 2012Co-Authors: Cristiano Schetini De Azevedo, Robert J. Young, Marcos RodriguesAbstract:The capacity to recognize and respond to preda- tors can be lost by captive animals. Habituation to humans caused by the captive environment can be transferred to other stimuli, such as predators, a situation that conservation biologists wish to avoid. Greater Rheas are threatened South American birds, for which there are plans for reintroduction programs in Brazil. The goal of this study was to evaluate the behavioral responses of captive-born greater Rheas to different models of predators and nonpredators. Seventeen captive-born greater Rheas, divided into four groups, from the Belo Horizonte Zoo, Brazil were studied. Three predator and three nonpredator models were presented to the birds and their behavioral responses recorded. Predators versus nonpredator models and the behavior of Rheas in three experimental phases (baseline, models, and postmodels) were analyzed. Captive-born greater Rheas modified their behaviors in the presence of both predator/nonpredator models, increasing alert and wary behaviors (alert, observ- ing, and pacing behaviors: P 0.05). In conclusion, antipredator training should be implemented to develop the expression of this behavior before reintroductions are attempted.
Cristiano Schetini De Azevedo - One of the best experts on this subject based on the ideXlab platform.
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Impacts of food-based enrichment on behaviour and physiology of male greater Rheas (Rhea Americana, Rheidae, Aves)
Universidade de São Paulo (USP). Museu de Zoologia (MZUSP)., 2019Co-Authors: Lima, Márcia Fontes Figueiredo, Cristiano Schetini De Azevedo, Young, Robert John, Viau PriscilaAbstract:Distress can be defined as a biological response of an individual to long-term threats to its homeostasis and it should be avoided from an animal welfare perspective. High levels of stress hormones and the expression of abnormal behaviours are responses normally observed in distressed animals. Captive environments can provoke distress, especially when inappropriate stimuli are provided to the animals. The concomitant use of behavioural and non-invasive hormonal measures is a means to evaluate captive animal welfare. Environmental enrichment is a tool that can reduce distress and minimize the expression of abnormal behaviour in captive animals. The aim of this study was to evaluate greater Rheas’ responses (behavioral and hormonal) to food-based enrichment. Three birds from the Belo Horizonte Zoo, Brazil were studied. The study was divided into three phases (baseline, enrichment and post-enrichment): fruits scattered around the birds’ enclosure were used as enrichment. Behaviour and faecal sampling were undertaken in all phases of the study. Abnormal behaviours and faecal glucocorticoid metabolites (GCM) levels showed significant reduction during the environmental enrichment phase, and a significative positive correlation between GCM production and abnormal pacing was observed. From the results of this study, we conclude that the use of food as environmental enrichment should be encouraged because of its positive effects on animal welfare. Besides, studies with larger groups of greater Rheas, with individuals of both sexes, should also be encouraged to evaluate if the results found in this pilot study are consistent and can be generalized to the species
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impacts of food based enrichment on behaviour and physiology of male greater Rheas Rhea americana rheidae aves
Papéis Avulsos de Zoologia, 2019Co-Authors: Marcia Fontes Figueiredo Lima, Cristiano Schetini De Azevedo, Robert J. Young, Priscila ViauAbstract:Distress can be defined as a biological response of an individual to long-term threats to its homeostasis and it should be avoided from an animal welfare perspective. High levels of stress hormones and the expression of abnormal behaviours are responses normally observed in distressed animals. Captive environments can provoke distress, especially when inappropriate stimuli are provided to the animals. The concomitant use of behavioural and non-invasive hormonal measures is a means to evaluate captive animal welfare. Environmental enrichment is a tool that can reduce distress and minimize the expression of abnormal behaviour in captive animals. The aim of this study was to evaluate greater Rheas’ responses (behavioral and hormonal) to food-based enrichment. Three birds from the Belo Horizonte Zoo, Brazil were studied. The study was divided into three phases (baseline, enrichment and post-enrichment): fruits scattered around the birds’ enclosure were used as enrichment. Behaviour and faecal sampling were undertaken in all phases of the study. Abnormal behaviours and faecal glucocorticoid metabolites (GCM) levels showed significant reduction during the environmental enrichment phase, and a significative positive correlation between GCM production and abnormal pacing was observed. From the results of this study, we conclude that the use of food as environmental enrichment should be encouraged because of its positive effects on animal welfare. Besides, studies with larger groups of greater Rheas, with individuals of both sexes, should also be encouraged to evaluate if the results found in this pilot study are consistent and can be generalized to the species.
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The fi shing Rhea: a new food item in the diet of wild greater Rheas (Rhea americana, Rheidae, Aves)
Revista Brasileira de Ornitologia - Brazilian Journal of Ornithology, 2013Co-Authors: Cristiano Schetini De Azevedo, Herlandes Penha Tinoco, João Bosco Ferraz, Robert J. YoungAbstract:The fi shing Rhea: a new food item in the diet of wild greater Rheas (Rhea americana, Rheidae, Aves)
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visitor influence on the behavior of captive greater Rheas Rhea americana rheidae aves
Journal of Applied Animal Welfare Science, 2012Co-Authors: Cristiano Schetini De Azevedo, Robert J. Young, Marcia Fontes Figueiredo Lima, Vitor Caetano Alves Da Silva, Marcos RodriguesAbstract:Visitors can affect and reduce the welfare of nonhuman animals. The Belo Horizonte Zoo, Brazil, had a group of greater Rheas intended for reintroduction to the wild. Because this group received public visitation, evaluating its effect on the birds' behavior and welfare was important. The study conducted 60 hr of behavioral observations: 30 with, and 30 without, visitors in front of the birds' enclosure. The study, conducted April–December 2009, collected data using scan sampling with instantaneous recording of behavior every minute. The study collected data on public behavior, visitor density, and time spent observing the birds. More than 4,000 persons visited the birds' enclosure: 9.86 s average time spent. Public behaviors most expressed were walking-watching-talking and stopped-watching-talking; visitors or not, greater Rheas' most expressed behaviors (inversed between treatments) were foraging and walking alert; defecating/urinating and other behaviors differed statistically between treatments. Walkin...
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visitor influence on the behavior of captive greater Rheas Rhea americana rheidae aves
Journal of Applied Animal Welfare Science, 2012Co-Authors: Cristiano Schetini De Azevedo, Robert J. Young, Marcia Fontes Figueiredo Lima, Vitor Caetano Alves Da Silva, Marcos RodriguesAbstract:Visitors can affect and reduce the welfare of nonhuman animals. The Belo Horizonte Zoo, Brazil, had a group of greater Rheas intended for reintroduction to the wild. Because this group received public visitation, evaluating its effect on the birds' behavior and welfare was important. The study conducted 60 hr of behavioral observations: 30 with, and 30 without, visitors in front of the birds' enclosure. The study, conducted April-December 2009, collected data using scan sampling with instantaneous recording of behavior every minute. The study collected data on public behavior, visitor density, and time spent observing the birds. More than 4,000 persons visited the birds' enclosure: 9.86 s average time spent. Public behaviors most expressed were walking-watching-talking and stopped-watching-talking; visitors or not, greater Rheas' most expressed behaviors (inversed between treatments) were foraging and walking alert; defecating/urinating and other behaviors differed statistically between treatments. Walking alert was most expressed in the presence of visitors; defecating/urinating and other behaviors were most expressed in their absence. Greater Rheas seemed to habituate to visitors. Birds' behaviors differed little in visitors' presence or absence.
Francisco Ponce-gordo - One of the best experts on this subject based on the ideXlab platform.
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Genetic identification of the ciliates from greater Rheas (Rhea americana) and lesser Rheas (Rhea pennata) as Balantioides coli
Parasitology Research, 2020Co-Authors: Juan José García-rodríguez, Joaquín Luis Navarro, Monica B. Martella, Rafael A. Martínez-díaz, Francisco Ponce-gordoAbstract:The ciliate species Balantioides coli can be cross-transmitted between humans and several animal species. Usually harmless, sometimes it can be pathogenic and cause the death of the host. In birds, B. coli has been confirmed in ostriches by genetic analysis, but the identification from South American greater Rheas ( Rhea americana ) and lesser Rheas ( Rhea pennata pennata ) is tentative. Since these species are reared for commercial purposes and for reintroduction into the wild, it is necessary to elucidate whether the ciliate from Rheas is B. coli to minimize health risks for humans and for other domestic and wild animals. Individual parasite cells are collected from Argentinean isolates of reared greater Rheas and of wild and reared lesser Rheas, and their ITS region was PCR amplified; the cloning products were sequenced and compared with sequences available in public databases. The results have shown that several sequence types are expressed at the same time in the parasite cells, and all correspond to B. coli , confirming the possibility of cross-transmission of the parasite between wild and reared South American Rheas and several mammal species and humans.
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Gastrointestinal parasites in greater Rheas (Rhea americana) and lesser Rheas (Rhea pennata) from Argentina
Veterinary Parasitology, 2012Co-Authors: Rafael A. Martínez-díaz, Joaquín Luis Navarro, Monica B. Martella, Francisco Ponce-gordoAbstract:Abstract Few data exist on the parasites of ratites, especially from regions within their natural range. It is only recently that extensive studies on the parasites of ostriches ( Struthio camelus ) have been published, mainly from European countries where commercial farming has expanded. Two species of ratites are native in South America: the lesser Rhea also known as Darwin's Rhea ( Rhea pennata ) and the greater Rhea ( Rhea americana ). Both species are considered near threatened by the IUCN and are included in the CITES’ Appendices I and II, respectively. Parasitological studies have conservation implications, as they allow us to assess the risk of transmission of pathogens from farmed ratites to wild populations. In this study 92 faecal samples from greater Rheas and 55 faecal samples from lesser Rheas from different localities in Argentine were analyzed to determine their gastrointestinal parasites. In greater Rheas the protozoa ( Balantidium coli -like and Entamoeba spp.) and helminths ( Fasciola hepatica and Deletrocephalus spp.). The protozoa had not previously been cited as parasites of greater Rheas in South America. Cysts and/or trophozoites of B. coli -like were found in 16.3% of the samples, while the prevalence of the remaining parasites was below 10%. Lesser Rheas harbored the protozoa B. coli -like, Entamoeba spp. and Chilomastix spp. as well as F. hepatica and nematode eggs and larvae. B. coli -like cysts were found in 20.0% of the samples, while the prevalence of the other parasites remained below 5%. Some of them had not been cited as infecting lesser Rheas yet.
