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1.
Parasitol Res ; 120(9): 3287-3296, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34374851

RESUMO

Literature data on toucans haemosporidians are scarce and all reports come from investigations in Brazil. Muniz et al. (Rev Bras Malariol 3: 339-356, Muniz et al., Rev Bras Malariol 3:339-356, 1951) and Muniz and Soares (Rev Bras Malar 611-617, Muniz J, Soares R de RL (1954) Nota sôbre um parasita do gênero Plasmodium encontrado no Ramphastos toco Müller, 1776, "Tucano-Açu", e diferente do Plasmodium huffi: Plasmodium pinottii n. sp. Rev Bras Malar 611 - 617.) described two Plasmodium species, P. huffi and P. pinottii, in Ramphastos toco. Later, Manwell and Sessler (J Protozol 18: 570-574, Manwell and Sessler, Malaria Parasites of Toucans J Protozol 18:570-574, 1971) established a new subspecies, P. nucleophilum toucani. In the last review on avian haemosporidians, Valkiunas (Valkiunas, Avian malaria parasites and other haemosporidia, CRC Press, New York, 2005) highlighted that P. huffi was insufficiently characterized, considering it a lost lineage. Also, the original description of P. huffi was considered insufficiently clear, due to a possible co-infection of the toucan hosts with a Novyella-like species. Here, we redescribed the species Plasmodium (Huffia) huffi based on morphological and molecular data, which were found in two toucan species, Ramphastos toco and Pteroglossus aracari from Brazil. Morphological features of the specimens are markedly the same as the original description. In R. toco, we observe two individuals infected, one infected only with P. huffi and one co-infected with P. huffi and the Novyella-like species, as observed in the original description. Also, we observe one R. toco infected only with the Novyella-like species, identified by morphological and molecular data as Plasmodium (Novyella) nucleophilum nucleophilum. In this way, it was possible to redescribe Plasmodium huffi in detail, without the doubt characters observed in the original description. Moreover, by applying species delimitation algorithms to a large Plasmodium phylogeny, we were able to identify new possible hosts for P. huffi and extend its geographic distribution to include North America.


Assuntos
Aves/parasitologia , Malária Aviária , Plasmodium , Animais , Brasil , Malária Aviária/parasitologia , Filogenia , Plasmodium/genética , Plasmodium/isolamento & purificação
2.
Parasitol Int ; 70: 70-76, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30726716

RESUMO

Plasmodium parasites can infect great variety of bird species around the world inflicting the so called avian malaria, an illness that could be fatal in some cases and consequently, should be monitored and widely included into conservation programs. The aim of this study was to characterize two lineages of Plasmodium (Haemamoeba) lutzi found in some birds in the Atlantic Forest of Minas Gerais - Brazil, that were morphologically identified after blood smears analyses under light microscopy and molecularly by sequencing the mitochondrial cytochrome b gene (cyt b). Besides these two lineages could be clearly morphologically identified as P.(H.) lutzi, some variations in comparison with its original description were noticed: absence of meronts and gametocytes (early and fully grown) in polychromatic erythrocytes, the larger size of pigment granules in meronts and gametocytes, and the presence of small vacuoles between pigment accumulation in fully grow macrogametocytes. Moreover, a certain degree of genetic intraspecific diversity was also observed across the lineages of P. (H.) lutzi, indicating the existence of polymorphisms within this taxon, which is uncommon in Haemosporida. These results allow discussion about species boundaries within avian hemosporidians and highlight the importance of multidisciplinary approaches for a more efficient species identification and characterization.


Assuntos
Doenças das Aves/parasitologia , Aves/parasitologia , Haemosporida/genética , Plasmodium/genética , Polimorfismo Genético , Animais , Animais Selvagens/parasitologia , Brasil , Citocromos b/genética , DNA de Protozoário/genética , Florestas , Haemosporida/isolamento & purificação , Malária Aviária , Microscopia , Filogenia , Plasmodium/isolamento & purificação
3.
Zootaxa ; 4500(4): 574-580, 2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30486051

RESUMO

The genus Metadinium includes ophryoscolecid ciliates, with two retractile ciliary zones in the anterior body portion, two broad skeletal plates, a lobed macronucleus and two contractile vacuoles. Species belonging to this genus were recorded in several geographical locations and in different host species. However, they were mostly described based on a single ciliatological technique, and until now, there is only one description of the infraciliary pattern in Metadinium ciliates (Metadinium medium). The present study performs the morphological and infraciliature characterization of four species belonging to Metadinium: M. esalqum, M. minorum, M. rotundatum and M. ypsilon; and presents taxonomic notes on the genus. The oral infraciliature in these four Metadinium species corresponds to the Diplodinium-type, pattern shared with genera Diplodinium, Diploplastron, Eudiplodinium, Eremoplastron and Polyplastron. A brief review conducted highlights the difficulty of delimiting Metadinium species due to the morphological similarity among them.


Assuntos
Cilióforos , Rúmen , Animais
4.
Zootaxa ; 4258(6): 581-585, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28609901

RESUMO

To date the genus Diploplastron comprised only one species of ophryoscolecid ciliate, Diploplastron affine, which is characterized by having two retractable ciliary zones in the anterior end of the body, two slender and juxtaposed skeletal plates on the right side, a rod shape macronucleus, and two contractile vacuoles. During study on the characterization of rumen ciliate community composition in Brazilian domestic sheep, we observed ciliates with atypical morphology but with diagnostic features of genus Diploplastron. This study describes Diploplastron dehorityi, a new species of ophryoscolecid ciliate, that differs from D. affine, primarily, in the morphology of skeletal plates, morphology of nuclear apparatus and body shape. In addition to the similarities between the new species and congener species, D. dehorityi has some morphological similarities to species of genus Eremoplastron.


Assuntos
Cilióforos , Animais , Brasil , Rúmen , Ovinos
5.
Parasitol Res ; 116(7): 1887-1897, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28477100

RESUMO

Haemosporidian blood parasites of the Plasmodium genus are the causative agents of avian malaria in many parts of the world. Despite the great diversity of Brazilian avifauna, few studies have been conducted to examine the haemosporidians of wild birds found in the Brazilian Atlantic Forest, especially those kept in captivity. This study aimed to re-examine and further characterize the South American avian parasite Plasmodium paranucleophilum using a multidisciplinary approach. Blood samples were collected from 68 captive birds representing 15 species found in the Atlantic Forest of southeastern Brazil. Morphometric and morphological characterization was performed, in addition to PCR and sequencing of the mitochondrial cytochrome b gene and subsequent phylogenetic analysis. The overall prevalence of P. paranucleophilum infection in the study was 13.23% (n = 9), with a mean parasitemia of 0.58%. We observed the highest parasitemia of 3.88% in Rupornis magnirostris. In our phylogenetic analysis, P. paranucleophilum and P lasmodium nucleophilum formed distinct, highly supported clades, with a mean genetic divergence of 2.48%. This study provides new morphological and molecular data, expanding our knowledge of the haemosporidians of wild birds in Brazil and highlighting the need for further investigation. The true depth of diversity in Brazilian avian haemosporidians remains largely unknown, and given the enormous variety of vectors and avian species, there may be many more species of these blood parasites yet to be described.


Assuntos
Malária Aviária/parasitologia , Plasmodium/classificação , Animais , Animais Selvagens , Aves , Brasil/epidemiologia , Citocromos b/genética , Florestas , Malária Aviária/epidemiologia , Parasitemia/veterinária , Filogenia , Plasmodium/citologia , Plasmodium/genética , Plasmodium/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA/veterinária
6.
Trop Anim Health Prod ; 49(4): 807-812, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28315137

RESUMO

A ciliate protozoa suppression can reduce methane production increasing the energy efficiency utilization by ruminants. The physicochemical characteristics of rumen fluid and the profile of the rumen protozoa populations were evaluated for sheep fed banana leaf hay in replacement of the Cynodon dactylon cv. vaqueiro hay. A total of 30 male sheep were raised in intensive system during 15 days of adaptation and 63 days of experimental period. The animals were distributed in a completely randomized design that included six replicates of five treatments with replacement levels (0, 25, 50, 75, and 100%) of the grass vaquero for the banana leaf hay. Samples of fluid were collected directly from the rumen with sterile catheters. Color, odor, viscosity, and the methylene blue reduction potential (MBRP) were evaluated and pH estimated using a digital potentiometer. After decimal dilutions, counts of genus protozoa were performed in Sedgewick Rafter chambers. The averages of pH, MBRP, color, odor, and viscosity were not influenced by the inclusion of the banana leaf hay. However, the total number of protozoa and Entodinium spp. population significantly decreased at 75 and 100% inclusions of banana leaf hay as roughage.


Assuntos
Cilióforos/isolamento & purificação , Musa , Rúmen/parasitologia , Carneiro Doméstico/parasitologia , Ração Animal/análise , Animais , Fermentação , Masculino , Folhas de Planta , Poaceae , Distribuição Aleatória , Ovinos
7.
Zootaxa ; 4088(2): 292-300, 2016 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-27394342

RESUMO

The species composition, prevalence, and average relative abundance of rumen ciliates were analyzed in 16 Brazilian sheep. 28 species of ciliates were identified belonging to 3 families: Isotrichidae, Ophryoscolecidae, and Parentodiniidae. Among these ciliates, Entodinium alces, Metadinium esalqum, and M. rotundatum were found for the first time in sheep, and other 12 species for the first time in Brazilian sheep. Different morphotypes of parentodiniid ciliates were identified in 7 of the 16 sheep analyzed and this is the second report of this family in ruminants. The species Entodinium contractum was redescribed based on the new data on the general morphological features; for the first time, we described the oral infraciliature, which in this species is of the Entodinium-type. In this species, it is noteworthy that the prominent vestibular polybrachykinety can be used as an important identifying characteristic.


Assuntos
Cilióforos/classificação , Rúmen/parasitologia , Animais , Tamanho Corporal , Brasil , Cilióforos/crescimento & desenvolvimento , Cilióforos/isolamento & purificação , Masculino , Ovinos/parasitologia
8.
Parasitol Res ; 115(1): 249-54, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26358101

RESUMO

Captive terrestrial tortoises of the species Chelonoidis carbonaria (n = 17) and Chelonoidis denticulata (n = 37) in the state of Minas Gerais, southeastern Brazil, were examined for hematozoans by using a combination of microscopic and molecular methods. Microscopic examination revealed young intra-erythrocytic forms in blood smears from both species of tortoises. The results of PCR, sequencing, and phylogenetic analysis indicated that these parasites belonged to the Haemoproteus spp., whose observed prevalence was 17.6 % in C. carbonaria and 13.5 % in C. denticulata. Phylogenetic analysis indicated that these sequences formed a clade that was grouped with other sequences of Haemoproteus spp. parasites in birds, separate from the clade formed by Haemoproteus spp. of reptiles. This study expands the information regarding the occurrence and distribution of hemosporidia in turtles and is the first study of blood parasites in C. carbonaria.


Assuntos
Haemosporida/classificação , Filogenia , Infecções Protozoárias em Animais/epidemiologia , Tartarugas/parasitologia , Animais , Sequência de Bases , Teorema de Bayes , Brasil/epidemiologia , DNA de Protozoário/sangue , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Feminino , Haemosporida/genética , Masculino , Prevalência , Infecções Protozoárias em Animais/sangue , Infecções Protozoárias em Animais/parasitologia , Análise de Sequência de DNA/veterinária
9.
Ciênc. rural ; 45(11): 2063-2068, Nov. 2015. tab
Artigo em Inglês | LILACS | ID: lil-762930

RESUMO

The aim of this study was to evaluate ruminal in situ degradability and in vitro digestibility of dry matter (DM) in concentrate supplements containing diverse potato flour pelletized with urea (0%, 4%, 8%, and 12% DM). Samples of feeds were incubated for 0, 2, 4, 8, 12, 24, 36, and 48h in the rumen of four fistulated sheep. Level of urea added had no significant effect (P>;0.05) on the soluble fraction (a) or potentially degradable fraction (b) of the pellets and ranged from 2.1% to 12.2% and 72.9% to 87.5%, respectively. Quadratic effects (P=0.03) of the rate of degradation of fraction "b" ranged from 4.75% h-1to 7.39% h-1; the estimated maximum value at 7.4% h-1was obtained when 5.9% urea was added to the pellet. Quadratic effects (P≤0.02) of the level of urea added to the pellets on the effective degradability (ED) of DM were evaluated after considering rumen passage rates of 2.5% h-1and 8% h-1; the maximum values of ED calculated under these rumen passage rates were estimated at 6.3% to 7.3% urea in the pellets. The in vitro digestibility of DM of the pellets showed a quadratic effect (P=0.02) at different levels of urea, with a maximum value of 96.9% achieved when 7.9% urea was added to the pellets. Our results suggest that the addition of 6-8% urea to pelleted feed promotes an increase in the in vitro digestibility and ED of DM.


Objetivou-se avaliar a degradação ruminal in situ da matéria seca (MS) e a digestibilidade in vitro de suplementos concentrados a base de farinha de batata diversa peletizada com ureia (0, 4, 8 e 12% da MS). Amostras de cada tratamento foram incubadas por 0, 2, 4, 8, 12, 24, 36 e 48 horas no rúmen de quatro ovinos fistulados. Não houve efeito (P>;0,05) do nível de inclusão de ureia sobre as frações solúvel ("a") e potencialmente degradável ("b") dos péletes, que variaram, respectivamente, de 2,1 a 12,1%, e de 72,9 a 87,5%. Foi observado efeito quadrático (P=0,03) para a taxa de degradação da fração "b", que variou de 4,75 a 7,39% h-1, sendo o valor máximo estimado em 7,4% h-1, obtido quando 5,9% de ureia foram incluídos no pélete. Foram observados efeitos quadráticos (P≤0,02) do nível de inclusão de ureia nos péletes sobre a degradabilidade efetiva (DE) da MS, considerando taxas de passagem no rúmen de 2, 5 e 8% h-1e os valores máximos de DE calculadas sob estas taxas de passagem no rúmen foram estimados com 6,3 a 7,3% de ureia nos péletes. A digestibilidade in vitro da MS dos péletes foi influenciada de forma quadrática (P=0,02) pelo nível de inclusão de ureia, com valor máximo de 96,9%, estimado quando 7,9% de ureia foram incluídos no pélete. A inclusão de 6 a 8% de ureia nos péletes promove incremento na digestibilidade in vitro e na degradabilidade efetiva da matéria seca.

10.
J Parasitol ; 101(6): 687-93, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26200719

RESUMO

Haemoproteid species have a wide global distribution, and they have been described in falcon species in several parts of the world. However, few studies in South America have focused on these birds. Haemoproteus spp. infections have been reported as the causative agents of serious histopathological changes, which can lead to the death of the host. Thus, this study aimed to molecularly and phylogenetically characterize Haemoproteus spp. in Caracara plancus, to characterize aspects of parasitism through clinical analysis and biochemical parameters, and to describe the histopathology of infection. To examine these aspects, 5 southern caracaras were examined clinically, and blood samples were collected. Blood smears were subsequently utilized in parasitemia calculations, PCR amplification, and serum biochemical investigations. Histological sections of the liver, kidneys, spleen, and heart were examined to check for possible histopathological changes. The birds showed clinical signs such as pallor and prostration that are consistent with Haemoproteus spp. infection. Moreover, the examination of the blood smears revealed 0.07% parasitemia in young gametocytes only. The PCR and sequencing results confirmed that the parasites belonged to Haemoproteus spp. The activity of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) enzymes, albumin, total serum proteins, and enzymatic urea were first described in C. plancus and serve as reference for future studies of bird species parasitized by Haemoproteus spp. Histopathology results showed signs of injury that were consistent with haemosporidian infection in the tissues of the analyzed organs. The present study is preliminary, and additional studies of Haemoproteus spp. infections in other bird species are needed to better understand the relationship between parasites and hosts, because despite the low parasitemia recorded, biochemical and histopathological changes in various organs were observed.


Assuntos
Doenças das Aves/parasitologia , Falconiformes/parasitologia , Haemosporida/genética , Infecções Protozoárias em Animais/parasitologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Sequência de Bases , Doenças das Aves/metabolismo , Doenças das Aves/patologia , Proteínas Sanguíneas/análise , DNA de Protozoário/sangue , DNA de Protozoário/química , Haemosporida/classificação , Haemosporida/patogenicidade , Rim/patologia , Fígado/patologia , Miocárdio/patologia , Parasitemia/veterinária , Filogenia , Infecções Protozoárias em Animais/metabolismo , Infecções Protozoárias em Animais/patologia , Alinhamento de Sequência/veterinária , Baço/patologia , Ureia/sangue
11.
Zoolog Sci ; 32(1): 8-15, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25660691

RESUMO

This review presents the principal methods used in taxonomic studies of rumen ciliates: live observation, Lugol staining, fixation and staining with methyl-green formalin saline (MFS) solution, protargol staining, silver carbonate impregnation, scanning electron microscopy and molecular techniques. Mastering these techniques is essential for successful research on the taxonomy of rumen ciliates. No single technique reveals all of the characteristics required for a complete description of a rumen ciliate; therefore, it is necessary to combine the use of these techniques as appropriate to the rumen ciliate group under study. Tables are provided to summarize: 1) morphological methods more appropriate for revealing morphological structures of interest, 2) morphological methods indicated for each group of rumen ciliates, and 3) main primers used for PCR amplification of the 18S rDNA of rumen ciliates.


Assuntos
Cilióforos/classificação , Rúmen/parasitologia , Animais , Cilióforos/ultraestrutura , Classificação , Coloração e Rotulagem
12.
J Eukaryot Microbiol ; 62(5): 584-90, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25712321

RESUMO

The 18S rDNA was used to infer oral ciliature patterns of evolution within the family Ophryoscolecidae, with the addition of five new sequences of ciliates from the genus Ostracodinium. Our data confirmed the monophyly of the subfamilies Entodiniinae and Ophryoscolecinae, but more analysis would be required for the definition of the status of the subfamily Diplodiniinae. The oral infraciliature patterns reflect evolutionary divergence in the family Ophryscolecidae, observing monophyly on Entodinium-type, Diplodinium-type, Ostracodinium-type, Epidinium-type, and Ophryoscolex-type. The ancestral infraciliature of Entodinium-type cannot be proven, however, the position of Entodinium-type showed closer of Diplodinium-type than Ophryoscolex-type, corroborating previous studies using morphological characters. The observed inconsistencies reflect the need to increase the number of 18S rDNA sequences to family Ophryoscolecidae and investigate the evolution of this group using other molecular markers.


Assuntos
Cilióforos/classificação , Cilióforos/genética , DNA Ribossômico/genética , Dados de Sequência Molecular , Filogenia
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