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1.
Anim Genet ; 52(4): 492-504, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34087001

RESUMO

Brazilian hair sheep constitute a genetic diversity hotspot. These animals are found in the harsh environments of the Brazilian Northwest (semi-arid) region. Genotypes (50K SNP chip) from seven Brazilian sheep breeds (five hair and two coarse wool types) and 87 worldwide breeds were used to test for population structure, admixture and genetic diversity. Moreover, phylogenetic trees evaluating migration events between genetic groups were built. Brazilian Somali, a fat-tailed breed, had a close relationship with East African breeds and clustered distinctly from other Brazilian breeds. Brazilian Blackbelly and Barbados Blackbelly had a close relationship. The Morada Nova breed did not show close relationships with European or African breeds, revealing a single migration event from an Algerian hair breed. Brazilian Fat-tail and Morada Nova share a common ancestor, but the former showed introgressions from Brazilian Somali and Afrikaner breeds, explaining the fat-tail phenotype. The Santa Inês breed received a substantial contribution from Brazilian Bergamasca and showed an admixed origin with recent introgressions from other breeds, mainly from Suffolk. Furthermore, Brazilian Somali and Brazilian Fat-tail are the most endangered sheep genetic resources in Brazil and should be the focus for ex situ conservation programs. In conclusion, Brazilian hair sheep show an African origin and are characterized by diverse genetic composition, reinforcing the need for conservation of these genetic resources, and at the same time, this highly diverse group has variability that can be used in breeding programs.


Assuntos
Pelo Animal , Cruzamento , Genoma , Genótipo , Carneiro Doméstico/genética , Pelo Animal/fisiologia , Animais , Brasil , Filogenia
2.
Genet Mol Res ; 16(1)2017 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-28363006

RESUMO

The aim of this study was to access the genetic diversity and relatedness between Canindé and British Alpine goat breeds in the States of Piauí and Ceará using microsatellite markers. Genomic DNA was isolated from hair samples of 99 goats belonging to six different flocks. A panel of polymorphic heterologous microsatellite loci was used to genotype individuals. The microsatellite markers resulted in a total number of 145 alleles, with an average of 8.5 alleles per locus. The observed and expected heterozygosities were ≥0.687 and ≥0.627, respectively, for all loci. The polymorphic information content showed that all loci were highly informative with an overall mean of 0.757. Overall FST across all populations and loci was 18%, which was consistent with the coefficient of gene differentiation (GST = 0.104). AMOVA revealed that 12.8% of the variation was captured between breeds. The Bayesian STRUCTURE clustering detected the maximum likelihood for a model of two genetically distinct groups, in agreement with the number of predefined studied breeds and the two-dimensional plot from the PCoA analysis. The exotic British Alpine breed and the naturalized Brazilian Canindé breed were clearly differentiated by the microsatellite markers, indicating that these two breeds have distant genetic identities, despite the phenotypic similarity.


Assuntos
Cabras/genética , Repetições de Microssatélites , Alelos , Animais , Brasil , Cruzamento , Mapeamento Cromossômico , DNA/genética , Deriva Genética , Variação Genética , Genética Populacional , Genótipo , Heterozigoto
3.
Chemosphere ; 164: 271-277, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27592316

RESUMO

Soil management may affect selenium (Se) adsorption capacity. This study investigated adsorption and desorption of Se (VI) in selected Brazilian soils from the Cerrado biome, an area of ever increasing importance for agriculture expansion in Brazil. Soil samples were collected from cultivated and uncultivated soils, comprising clayed and sandy soils. Following chemical and mineralogical characterization, soil samples were subjected to Se adsorption and desorption tests. Adsorption was evaluated after a 72-h reaction with increasing concentrations of Se (0-2000 µg L-1) added as Na2SeO4 in a NaCl electrolyte solution (pH 5.5; ionic strength 15 mmol L-1). Desorption, as well as distribution coefficients (Kd) for selenate were also assessed. Soil management affected Se adsorption capacity, i.e., Se adsorbed amounts were higher for uncultivated soils, when compared to cultivated ones. Such results were also supported by data of Kd and maximum adsorption capacity of Se. This fact was attributed mainly to the presence of greater amounts of competing anions, especially phosphate, in cultivated soils, due to fertilizer application. Phosphate may compete with selenate for adsorption sites, decreasing Se retention. For the same group of soils (cultivated and uncultivated), Se adsorption was greater in the clayed soils compared to sandy ones. Our results support the idea that adding Se (VI) to the soil is a good strategy to increase Se levels in food crops (agronomic biofortification), especially when crops are grown in soils that have been cultivated over the time due to their low Se adsorption capacity (high Se availability).


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Ácido Selênico/análise , Poluentes do Solo/análise , Solo/química , Adsorção , Brasil , Ecossistema , Fosfatos/análise , Fosfatos/química , Ácido Selênico/química , Poluentes do Solo/química , Clima Tropical
4.
J Anim Sci ; 93(10): 4629-36, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26523555

RESUMO

The objective of this study was to assess genetic diversity among 5 Brazilian (155 animals) and 5 U.S. goat (120 animals) breeds using 23 microsatellite markers. Samples from the United States represented a broad geographic distribution whereas Brazilian samples were from the northeast region. Samples from Boer were common to each country's breed count. Expected and observed heterozygosity among breeds ranged from 0.55 to 0.72, suggesting ample genetic diversity in the breeds evaluated. United States Angora, U.S. Spanish, and Brazilian Nambi ranked highest for allelic richness, averaging 6.1, 7.1, and 6.5 alleles per locus, respectively. Angora and Spanish also ranked highest in private alleles (7 and 9, respectively). Using STRUCTURE, the U.S. Spanish were also found to share a common cluster assignment with Brazilian Nambi, suggesting that progenitor breeds may have been the same and passed through the Canary Islands or Cape Verde in route to the New World. When non-Boer breeds were pooled by country, the effect of the subpopulation compared with total population () = 0.05, suggesting minor genetic differences exist between countries. The lack of genetic structure among goat breeds when compared with other species (e.g., vs. ) suggests goat breeds may exhibit a plasticity that facilitates productivity across a wide range of countries and environments. Taken a step further, the concept of breed for meat goats may not be as relevant for goat production.


Assuntos
Variação Genética , Cabras/genética , Repetições de Microssatélites , Alelos , Distribuição Animal , Animais , Brasil , Cruzamento , Heterozigoto , Estados Unidos
5.
Neotrop Entomol ; 42(6): 600-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27193278

RESUMO

Sexual dichromatism and sexual dimorphism of body size are reasonably well studied in butterflies. Sexual size dimorphism of color pattern elements, however, is much less explored. The object of this study is Heliconius, a genus of butterflies well known for the coevolution between mate color preferences and mimicry. Given the sexual role of wing coloration, we investigated the existence of sexual size dimorphism in the wing color elements of a mimetic pair-Heliconius erato phyllis Fabricius and Heliconius besckei Ménétriés-and analyzed the allometric patterns of these traits. Correlation between size of elements in the dorsal and ventral wing surfaces were also estimated. In both species, three out of four elements were larger in males, but the non-dimorphic element was not the same. With regard to the allometric patterns, our most important finding was that smaller males of one species have proportionally larger yellow bars. This is the first study specifically concerning quantitative sexual dimorphism in the coloration of this well-known genus of butterflies and it opens new prospects to investigate sex-related natural selection and sexual selection of color pattern elements.


Assuntos
Borboletas , Cor , Caracteres Sexuais , Asas de Animais , Animais , Feminino , Masculino , Fenótipo
6.
Arq. Inst. Biol ; 80(1): 91-97, jan.-mar.2013.
Artigo em Português | LILACS, VETINDEX | ID: biblio-1462207

RESUMO

Objetivou-se testar a atividade inseticida de pós vegetais em Sitophilus zeamais. Foram testados os pós de Anadenanthera colubrina (folhas); Annona muricata (sementes); Azadirachta inidica (folhas e flores); Caesalpinia pyramidalis (folhas), Chenopodium ambrosioides (folhas e flores); Cymbopogon sp.(folhas); Cymbopogon citratus (folhas); Momordica charantia (folhas e frutos); Piper nigrum (sementes); e Ricinus communis (folhas). Além disso, avaliou-se o potencial inseticida de folhas e flores de C. ambrosioides em diferentes dosagens. Na avaliação de repelência foi estabelecido um índice de preferência, e utilizado o teste t para comparação das médias das espécies vegetais. Também foi realizada a comparação das médias das plantas que foram classificadas como repelentes. Para avaliação da mortalidade, procedeu-se a análise de variância e a comparação das médias pelo teste de Tukey e também o teste t para comparação das médias dos tratamentos C. ambrosioides e P. nigrum. Os dados de emergência foram analisados pelo teste de Tukey. Para avaliar os dados de mortalidade, ocasionados por C. ambrosioides, determinou-se a CL50 utilizando a análise de Probit. Os dados de emergência foram verificados pela análise de regressão. As plantas que provocaram repelência foram Cymbopogon sp., C. citratus e C. ambrosioides. A planta que mais afetou a sobrevivência da praga foi C. ambrosioides, que provocou mortalidade total dos insetos infestantes e nenhuma emergência. Adultos de S. zeamais são mais suscetíveis a concentração de 0,125 g do pó de C. ambrosioides.


Effect of plant powders on Sitophilus zeamais (Mots., 1855) (Coleoptera: Curculionidae). The objective of the present study was to test the insecticidal activity of vegetable powders on Sitophilus zeamais. Powders of Anadenanthera colubrina (leaves); Annona muricata (seed); Azadirachta inidica(leaves and flowers);Caesalpinia pyramidalis(leaves);Chenopodium ambrosioides (leaves and flowers);Cymbopogon sp. (leaves);Cymbopogon citratus (leaves); Momordica charantia (leaves and fruits);Piper nigrum (seed); andRicinus communis (leaves) were evaluated. In addition, we evaluated the insecticidal potential of leaves and flowers of C. ambrosioidesat different dosages. In the evaluation of repellency a preference index was established, and the t test was used to compare the means of plant species. The means of plants that were classified as repellent were also compared. To assess mortality, we proceeded with the analysis of variance and comparison of means by Tukey test and also the t test for comparing the means of the C. ambrosioides and P. nigrum treatments. The emergence data were analyzed by Tukey test. To evaluate the data on mortality caused by C. ambrosioides, the CL50 was determined using Probit analysis. The emergence data were verified by regression analysis. Plants that caused repellency were Cymbopogon sp., C. citratusand C. ambrosioides. The plant that most affected the survival of the pest wasC. ambrosioides, which caused total mortality of insect infestations and no adult emergence. Adults of S. zeamaisare most susceptible to the concentration of 0.125 g ofC. ambrosioides powder.


Assuntos
Inseticidas/análise , Pragas da Agricultura , Zea mays/classificação , Plantas
7.
Arq. Inst. Biol. ; 80(1): 91-97, jan.-mar. 2013.
Artigo em Português | VETINDEX | ID: vti-325498

RESUMO

Objetivou-se testar a atividade inseticida de pós vegetais em Sitophilus zeamais. Foram testados os pós de Anadenanthera colubrina (folhas); Annona muricata (sementes); Azadirachta inidica (folhas e flores); Caesalpinia pyramidalis (folhas), Chenopodium ambrosioides (folhas e flores); Cymbopogon sp.(folhas); Cymbopogon citratus (folhas); Momordica charantia (folhas e frutos); Piper nigrum (sementes); e Ricinus communis (folhas). Além disso, avaliou-se o potencial inseticida de folhas e flores de C. ambrosioides em diferentes dosagens. Na avaliação de repelência foi estabelecido um índice de preferência, e utilizado o teste t para comparação das médias das espécies vegetais. Também foi realizada a comparação das médias das plantas que foram classificadas como repelentes. Para avaliação da mortalidade, procedeu-se a análise de variância e a comparação das médias pelo teste de Tukey e também o teste t para comparação das médias dos tratamentos C. ambrosioides e P. nigrum. Os dados de emergência foram analisados pelo teste de Tukey. Para avaliar os dados de mortalidade, ocasionados por C. ambrosioides, determinou-se a CL50 utilizando a análise de Probit. Os dados de emergência foram verificados pela análise de regressão. As plantas que provocaram repelência foram Cymbopogon sp., C. citratus e C. ambrosioides. A planta que mais afetou a sobrevivência da praga foi C. ambrosioides, que provocou mortalidade total dos insetos infestantes e nenhuma emergência. Adultos de S. zeamais são mais suscetíveis a concentração de 0,125 g do pó de C. ambrosioides. (AU)


Effect of plant powders on Sitophilus zeamais (Mots., 1855) (Coleoptera: Curculionidae). The objective of the present study was to test the insecticidal activity of vegetable powders on Sitophilus zeamais. Powders of Anadenanthera colubrina (leaves); Annona muricata (seed); Azadirachta inidica(leaves and flowers);Caesalpinia pyramidalis(leaves);Chenopodium ambrosioides (leaves and flowers);Cymbopogon sp. (leaves);Cymbopogon citratus (leaves); Momordica charantia (leaves and fruits);Piper nigrum (seed); andRicinus communis (leaves) were evaluated. In addition, we evaluated the insecticidal potential of leaves and flowers of C. ambrosioidesat different dosages. In the evaluation of repellency a preference index was established, and the t test was used to compare the means of plant species. The means of plants that were classified as repellent were also compared. To assess mortality, we proceeded with the analysis of variance and comparison of means by Tukey test and also the t test for comparing the means of the C. ambrosioides and P. nigrum treatments. The emergence data were analyzed by Tukey test. To evaluate the data on mortality caused by C. ambrosioides, the CL50 was determined using Probit analysis. The emergence data were verified by regression analysis. Plants that caused repellency were Cymbopogon sp., C. citratusand C. ambrosioides. The plant that most affected the survival of the pest wasC. ambrosioides, which caused total mortality of insect infestations and no adult emergence. Adults of S. zeamaisare most susceptible to the concentration of 0.125 g ofC. ambrosioides powder.(AU)


Assuntos
Inseticidas/análise , Zea mays/classificação , Pragas da Agricultura , Plantas
8.
Water Sci Technol ; 59(9): 1841-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19448321

RESUMO

The market for coconut water causes environmental problems as it is one of the major agro-industrial solid wastes in some developing countries. With the aim of reusing the coconut husk, Embrapa developed a system for processing this raw material. During the dewatering stage Coconut Husk Liquor (CHL) is generated with chemical oxygen demand (COD) varying from 60 to 70 g/L due to high concentrations of sugars and tannins. The present study evaluated the feasibility of anaerobic treatment of CHL through Anaerobic Toxicity Assay and the operation of a lab-scale Upflow Anaerobic Sludge Blanket (UASB) reactor. Results showed that CHL can be treated through a UASB reactor operating with an OLR that reaches up to 10 kg/m3.d and that is maintained stable during the whole operation. With this operational condition, the removal efficiency was higher than 80% for COD and approximately 78% for total tannins, and biogas production was 20 m3 of biogas or 130 KWh per m3 of CHL. Seventy-five percent of the biogas composition was methane and toxicity tests demonstrated that CHL was not toxic to the methanogenic consortia. Conversely, increasing the concentration of CHL leads to increased methanogenic activity.


Assuntos
Reatores Biológicos , Cocos , Eliminação de Resíduos Líquidos/métodos , Anaerobiose
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