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1.
Trypanosoma (Megatrypanum) melophagium is a parasite of sheep transmitted by sheep keds, the sheep-restricted ectoparasite Melophagus ovinus (Diptera: Hippoboscidae). Sheep keds were 100% prevalent in sheep from five organic farms in Croatia, Southeastern Europe, whereas trypanosomes morphologically compatible with T. melophagium were 86% prevalent in the guts of the sheep keds. Multilocus phylogenetic analyses using sequences of small subunit rRNA, glycosomal glyceraldehyde-3-phosphate dehydrogenase, spliced leader, and internal transcribed spacer 1 of the rDNA distinguished T. melophagium from all allied trypanosomes from other ruminant species and placed the trypanosome in the subgenus Megatrypanum. Trypanosomes from sheep keds from Croatia and Scotland, the only available isolates for comparison, shared identical sequences. All biologic and phylogenetic inferences support the restriction of T. melophagium to sheep and, especially, to the sheep keds. The comparison of trypanosomes from sheep, cattle, and deer from the same country, which was never achieved before this work, strongly supported the host-restricted specificity of trypanosomes of the subgenus Megatrypanum. Our findings indicate that with the expansion of organic farms, both sheep keds and T. melophagium may re-emerge as parasitic infections of sheep.  相似文献   

2.
From April 1984 to March 1985, a Trypanosoma lewisi prevalence of 21.7% was found in 429 Rattus norvegicus trapped in Belo Horizonte, State of Minas Gerais, Brazil. The infection rates were higher in male and young rats and could be attributed to ecological and behavioral factors. T. lewisi was observed in rats measuring between 60 and 250 mm. Data about monthly T. lewisi infections throughout the year are presented for the first time in Brazil, with the highest prevalences observed in the warm-rainy season (October to March).  相似文献   

3.
Aerobiologia - Primary biological aerosol particles (PBAPs) are involved in multiple phenomena ranging from seasonal allergies to pandemic diseases. Furthermore, PBAPs that act as ice nuclei, might...  相似文献   

4.
Congenital Neospora caninum infection was diagnosed in two Saanen goat kids from two distinct herds with a history of abortion and weak newborn goat kids in the Southern region of the State of Minas Gerais, Brazil. The first kid was weak at birth, had difficulty to rise and was unable to nurse. Gross lesions of porencephaly and hydrocephalus ex vacuo were seen. Multifocal necrosis, gliosis and non-supurative encephalitis were observed in the brain. Several parasitic cysts with a thick wall that reacted strongly only with polyclonal antiserum to Neospora caninum were seen in the cerebral cortex, brain stem and cerebellum. The second kid was born from a Neospora caninum seropositive mother that aborted in the last pregnancy. It was born without clinical signs. The diagnosis of neosporosis was based on antibody titer of 1:800 to N. caninum by indirect fluorescence antibody test obtained from blood collected before the goat kid ingested the colostrum and Neospora caninum DNA was detected by polymerase chain reaction and sequenced from placenta. This is the first report of neosporosis in goats in the southeast region of Brazil.  相似文献   

5.
Published and unpublished observations on geographical distribution of Biomphalaria snails in the State of Minas Gerais, Brazil, were compiled. This work is aimed at knowing the present occurrence of Biomphalaria species in this region, and at contributing to the elaboration of the planorbid chart of Minas Gerais. In malacological surveys, performed by several researchers, the presence of seven species of this genus was recorded. Those planorbids were found in 12 mesoregions, in 283 (33.1%) municipalities out of 853 with the following distribution: B. glabrata (185 municipalities), B. straminea (125), B. tenagophila (58), B. peregrina (57), B. schrammi (26), B. intermedia (20) and B. occidentalis (2). B. glabrata and B. tenagophila are found naturally infected by Schistosoma mansoni in Minas Gerais. In 24 municipalities the three snail hosts of S. mansoni in Brazil, B. glabrata, B. tenagophila and B. straminea, are present.  相似文献   

6.
The stingless bee Melipona rufiventris is an important pollinator in several Brazilian ecosystems. Originally widely distributed in Minas Gerais (MG) state, this species is becoming very rare. Therefore this species was included in the endangered species list of MG. We used isoenzyme data for a better understanding of the genetic structure of several M. rufiventris colonies. Samples of 35 colonies were collected from 12 localities and evaluated by nine enzymatic systems, which yielded 17 loci. M. rufiventris genetic variation was found to be low, typical of an endangered species. The proportion of polymorphic loci was 5.88% in both ecosystems. Only Est-4 was polymorphic in colonies from the Forest and Mdh-1 in colonies from the Cerrado. The expected heterozygosity ranged from 0.0068 in the Cerrado to 0.0078 in the Forest. Despite this, enzyme electrophoretic analyses provided a good idea of the diversity between samples from Cerrado and Forest which reinforce the existence of two different forms of M. rufiventris in MG, one present in the Cerrado and the other in Forest. This information is of great importance for the conservation of, M. rufiventris in MG.  相似文献   

7.
Anthracnose disease of common bean (Phaseolus vulgaris), caused by Colletotrichum lindemuthianum, is responsible for extensive yield losses worldwide. This pathogen is known to vary greatly in its pathogenicity. Control strategies include chemical control and, mainly, the development of resistant cultivars, taking into account the population structure of C. lindemuthianum. The objective of this study was to investigate the pathogenic and genetic diversity and population structure among C. lindemuthianum isolates collected in Minas Gerais state, Brazil. When these isolates were inoculated on 12 differential cultivars, a total of 10 races were identified within a series of 48 isolates collected in Minas Gerais, Brazil. Races 65, 81 and 73 were the most frequent races and occurred in most of the regions. This study also detected race 337, which had not been reported previously in the literature. Random amplified polymorphic DNA (RAPD) analysis performed on the same 48 isolates revealed great genetic diversity, clustering the series into five groups at a maximum similarity value of 89.6%. There was no clear relationship between the loci sampled by RAPD markers and the pathogenic characterization. Analysis of molecular variance showed that 96.06% of the variability was contained within regions and 3.94% among regions, indicating a high exchange of genetic material among the regions of the State. Most of the variability was detected within races (75.24%). The pathogenicity and RAPD assays corroborated the broad genetic diversity of the pathogen and the results have been useful in breeding for resistance to anthracnose.  相似文献   

8.
Rabies is a viral zoonosis affecting mammal species and causes large economic losses. Included among the neglected diseases, it is still insufficiently addressed by governments and the international community, despite formal surveillance and control programs. This study used a dataset of 10,112 rabies diagnoses in animals provided by the Brazilian passive surveillance system from 2001 to 2012. The positivity rate of the tested samples was 26.4%, and a reduction in the total samples sent during the last six years was observed. The kernel density map indicated case concentration in the south region and a decrease in density of rabies cases in the second period studied (2007 to 2012). The directional trend of positive rabies diagnoses remained in the south region, as shown by the standard deviational ellipse. The spatial scan statistic identified three large clusters of positive diagnoses, one in the first period (2001-2006) and two in the second period (2007-2012), indicating an expansion of risk areas. The decrease in rabies cases from 2006 to 2012 does not necessarily reflect lower viral circulation or improvement in actions by epidemiological surveillance; this decrease could indicate a deficiency in epidemiological surveillance during the observation period due to the increase in the silent areas. Surveillance should maintain an increasing or constant number of tests during the years in addition to a reduction in the number of outbreaks of rabies, which would indicate a lower positivity rate. The findings in this study indicate deterioration in the effectiveness of the passive surveillance for rabies. The number of rabies cases, total number of tests performed and positivity rate are good indicators for evaluating passive surveillance. This paper can function as a guide for the assessment and improvement of the actions in passive surveillance of rabies.  相似文献   

9.
The concept of ecological niche, considered by the food dimension point of view, was used to characterize a small farmers community from the south of Minas Gerais State (Brazil). Ten small farmer families and 76 different meals eaten by them were evaluated in this study, during three different periods: September 1995 (end of the dry season), December 1995 (rainy season) and April 1996 (end of the rainy season). The analysed community appeared to depend markedly on certain food items showing little seasonal variation in their diet and appeared also to be self-sufficient in food supply, with satisfactory nutritional status. The food niche breadth for the studied small farmer families was always below 50%, with high seasonal overlap of the food niche, around 72% to 80%. The results are discussed based on social-cultural, economical and agrarian context.  相似文献   

10.
The aim of this paper was to verify the sand fly species collected with Malaise trap in the cities of Divinópolis and Pedra do Indaiá, both located in Minas Gerais state. Collections were carried out between November 2003 and October 2004. Thirty two specimens were captured belonging to seven species: Pintomyia monticola (Costa Lima), Nyssomyia whitmani (Antunes & Coutinho), Pintomyia christenseni (Young & Duncan), Evandromyia cortelezzii (Brèthes), Sciopemyia sordellii (Shannon & Del Ponte), Pintomyia pessoai (Coutinho & Barretto) and Psathyromyia aragaoi (Costa Lima).  相似文献   

11.
Quantifying diversity is an old challenge for ecologists and is also a social demand given the increasing threats to natural areas. We sought to work on these issues by using data from 158 vegetation remnants (over 350,000 trees) in southeastern Brazil (Minas Gerais State—MG, nearly 600,000 km2). Specifically, we sought to answer the following questions. (1) How many trees and tree species currently exist in MG vegetation remnants? (2) How much of such biodiversity is present in each vegetation domain (Atlantic Forest, Cerrado and Caatinga) and vegetation type (Seasonally Dry tropical forest “semideciduous”, Seasonally Dry tropical forest “deciduous”, Rain Forest, Swamp, Cerrado and Cerradão) in MG? (3) How much has been lost in regards to tree amount and tree species? We built a 0.1-degree cell grid to estimate the number of trees via spatial regression and used Fisher’s alpha and Fisher’s log series to provide estimates on how many tree species there are and were in MG. We found the number of trees in Minas Gerais to be approximately 24.5 × 109, and the number of tree species to be between 3592 and 3743. The most abundant species distribution among the vegetation domains and vegetation types followed inversely the environmental heterogeneity of the classes. Consequently, the most abundant species in MG belonged to the Cerrado domain, where there was less environmental heterogeneity. The numbers of trees and tree species lost were estimated at 68.54 and 4.03–8.42% of the original values, respectively. We discuss that due to the consequences of human impacts that go back in the region for over a thousand years, other processes not considered in this study, such as habitat degradation by isolation, alterations of food webs, unsustainable use, and climate change, might have caused local extinctions and potentially increased the number of species lost. We believe our results may guide conservation initiatives by providing a base for future environmental laws, parks planning, and the development of more appropriate vegetation management techniques in MG. In addition, our results may inspire future quantitative ecological studies in the tropics.  相似文献   

12.
Eight streblid species were collected from eight phyllostomid bat species, from April to November 1997, at or near the Reserve "Parque Estadual do Rio Doce", Minas Gerais, Southeastern Brazil. In total, 48 specimens of streblid were removed from 57 phyllostomid bats. Most of batflies species were associated with a single species of the host, and only Paratrichobius longicrus (Miranda Ribeiro) and Trichobius joblingi Wenzel were recorded on three bat species. Trichobius lonchophyllae Wenzel represents a new record for the Brazilian Southeastern region.  相似文献   

13.
Partamona is a Neotropical genus of stingless bees that comprises 33 species distributed from Mexico to southern Brazil. These bees are well-adapted to anthropic environments and build their nests in several substrates. In this study, 66 colonies of Partamona helleri from five localities in the Brazilian state of Minas Gerais (São Miguel do Anta, Teixeiras, Porto Firme, Viçosa and Rio Vermelho) were analyzed using nine microsatellite loci in order to assess their genetic variability. Low levels of observed (Ho = 0.099-0.137) and expected (H e = 0.128-0.145) heterozygosity were encountered and revealed discrete genetic differentiation among the populations (F ST = 0.025). AMOVA further showed that most of the total genetic variation (94.24%) in P. helleri was explained by the variability within local populations.  相似文献   

14.
We report the isolation of Histoplasma capsulatum from a culture of the viscera of Didelphis albiventris, one of the marsupial species found in Brazil. To our knowledge, this is the first report of the isolation of this fungus from this mammalian species. This finding confirms the ubiquitous presence of H. capsulatum in nature.  相似文献   

15.
A species ofPseudolaelia (Orchidaceae) from Minas Gerais, Brazil, is described as new to science.  相似文献   

16.
Two new species of Vellozia from the Espinhaco range in the State of Minas Gerais, Brazil, are described and their taxonomic relationships are considered. A discussion of their geographical distribution and an account of their leaf anatomy is provided.  相似文献   

17.
Aims: To evaluate the antiviral activity of Bignoniaceae species occurring in the state of Minas Gerais, Brazil. Methods and Results: Ethanol extracts of different anatomical parts of bignoniaceous plant species have been evaluated in vitro against human herpesvirus type 1 (HSV‐1), vaccinia virus (VACV) and murine encephalomyocarditis virus (EMCV) by the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay. A total of 34 extracts from 18 plant species selected according to ethnopharmacological and taxonomic criteria were screened. Fifteen of the 34 extracts (44·1%) have disclosed antiviral activity against one or more of the viruses assayed with EC50 values in the range of 23·2 ± 2·5–422·7 ± 10·9 μg ml?1. Conclusions: Twelve of the 34 extracts (35·3%) might be considered promising sources of antiviral natural products, as they have shown EC50 ≤ 100 μg ml?1. The present screening discloses the high potential of the Bignoniaceae family as source of antiviral agents. Significance and Impact of the Study: Active extracts were identified and deserve bioguided studies for the isolation of antiviral compounds and studies on mechanism of action.  相似文献   

18.
In the present study the tick prevalence, mean intensity of infestation and species were recorded on birds captured between January 2009 and December 2010 in the Ecological Station Pirapitinga-ESEC from Minas Gerais State, Brazil. A total of 967 birds, from 15 families and 40 species were captured and 165 (17.1 %) individuals were parasitized by ticks. Of these 160 (97 %) belonged to the order Passeriformes. Five tick species were identified: Amblyomma longirostre (n = 274) was the most common species followed by Amblyomma parvum (n = 43), Amblyomma nodosum (n = 39), Amblyomma ovale (n = 24) and Riphicephalus sanguineus (n = 7). None of 61 unengorged larvae molted to nymph. The mean intensity of infestation was 2.7 ± 2.4 ticks per bird (448 ticks/165 birds) ranging from 1 to 10. Only 19 (11.4 %) birds were infested with one species of tick. The remaining birds were infested by two, three or four species of ticks. Also new hosts for all five ticks were recorded. Only nymphs were recorded throughout the year with two similar peaks during autumn and winter 2009 and 2010.  相似文献   

19.
In the last few years the number of human cases of American visceral leishmaniasis in the Metropolitan Region of Belo Horizonte (MRBH), Minas Gerais, Brazil has increased, indicating an elevation in the transmission rate of the disease. The total number of notified human cases in the MRBH since 1994, when the first case was identified, up to 1999 was 345 of which 223 (65%) were from the city itself, indicating an urbanization of the disease in this region of Minas Gerais. The age distribution of visceral leishmaniasis cases in the MRBH shows a higher prevalence in children from 0-4 years old, responsible for 28.9% of the notifications. Clinical and immunological findings from dogs infected with Leishmania chagasi are described. The majority of these animals showed no sign of the disease. Sera from all infected dogs showed detectable Leishmania-induced high titles of antibodies based on the results of an indirect fluorescent antibody test. Samples of isolated Leishmania from human and dogs were characterized as L. (L.) chagasi by biochemical and molecular techniques.  相似文献   

20.
Passiflora boticarioana, a new species of subgen.Passiflora, supersect.Stipulata, sect.Dysosmia, from the state of Minas Gerais, Brazil, is described, illustrated, and compared with morphologically similar species.  相似文献   

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