RESUMO
Gene-gene interactions cause hidden genetic variation in natural populations and could be responsible for the lack of replication that is typically observed in complex traits studies. This study aimed to identify gene-gene interactions using the empirical Hilbert-Schmidt Independence Criterion method to test for epistasis in beef fatty acid profile traits of Nellore cattle. The dataset contained records from 963 bulls, genotyped using a 777 962k SNP chip. Meat samples of Longissimus muscle, were taken to measure fatty acid composition, which was quantified by gas chromatography. We chose to work with the sums of saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA), omega-3 (OM3), omega-6 (OM6), SFA:PUFA and OM3:OM6 fatty acid ratios. The SNPs in the interactions where P < 10 - 8 were mapped individually and used to search for candidate genes. Totals of 602, 3, 13, 23, 13, 215 and 169 candidate genes for SFAs, MUFAs, PUFAs, OM3s, OM6s and SFA:PUFA and OM3:OM6 ratios were identified respectively. The candidate genes found were associated with cholesterol, lipid regulation, low-density lipoprotein receptors, feed efficiency and inflammatory response. Enrichment analysis revealed 57 significant GO and 18 KEGG terms ( P < 0.05), most of them related to meat quality and complementary terms. Our results showed substantial genetic interactions associated with lipid profile, meat quality, carcass and feed efficiency traits for the first time in Nellore cattle. The knowledge of these SNP-SNP interactions could improve understanding of the genetic and physiological mechanisms that contribute to lipid-related traits and improve human health by the selection of healthier meat products.
Assuntos
Bovinos/genética , Epistasia Genética , Estudo de Associação Genômica Ampla/veterinária , Genoma , Metabolismo dos Lipídeos/genética , Carne Vermelha/análise , Animais , MasculinoRESUMO
Here, we describe Araucariocladus amfractus sp. nov., and compare it to the previously monotypic type-species, A. hiems. The new species can be distinguished from A. hiems by the following combination: colour pattern overall dark-brown; pedicel three times shorter than antennomere III and slightly wider than long; distance between antennal sockets as wide as 3/5 clypeal width; labial palpomere III with sides divergent towards apex, apical margin longer than dorsal and shorter than ventral margin; pronotum 1.5x wider than long, anterior margin somewhat sinuose, with a shallow angle anteriad, posterior margin almost straight. A. amfractus sp. nov. is, prima facie, endemic to the Itatiaia Massif, part of the Mantiqueira Mountain Range, Southeastern Brazil. We provide illustrations of the diagnostic features, and an occurrence map for the Araucariocladus species. Finally, we report a previously unrecognized intra-specific variation in the antennomere numbers of A. hiems, a feature also present in Araucariocladus amfractus sp. nov., and adjust the generic diagnosis to include species with 17 or 18 antennomeres. [Zoobank LSID: urn:lsid:zoobank.org:act:C335B064-FBD4-4256-983D-B17DF06BAA0D].
Assuntos
Besouros , Vaga-Lumes , Animais , Brasil , CorRESUMO
Cracids are medium to large frugivorous birds that are endemic to the Neotropics. Because of deforestation and overhunting, many species are threatened. The conservation of several species has relied on captive breeding and reintroduction in the wild, but captive populations may be inbred. Microsatellite tools can permit the construction of genetic pedigrees to reduce inbreeding, but only a few loci are available for this group of birds. Here, we present 10 novel polymorphic microsatellite loci and the cross-amplification of these and of 10 additional loci available in the literature in a panel of 5 cracid species, including 3 species with high conservation concern. We provide the first polymorphic loci for the jacutinga, Aburria jacutinga (N = 8), and red-billed curassow, Crax blumenbachii (N = 9), and additional loci for bare-faced curassow, C. fasciolata (N = 8), Alagoas curassow, Pauxi mitu (N = 5), and razor-billed curassow, P. tuberosa (N = 5). The average number of alleles was 2.9 for A. jacutinga, 2.7 for C. blumenbachii, 3.5 for C. fasciolata, 2.6 for P. mitu, and 5.7 for P. tuberosa. The mean expected heterozygosities were 0.42, 0.40, 0.48, 0.37, and 0.59, respectively. The average probabilities that the set of loci would not exclude a pair of parents of an arbitrary offspring were 2.9% in A. jacutinga, 1% in C. blumenbachii, 0.5% in C. fasciolata, 0.4% in P. mitu, and 0.002% in P. tuberosa suggesting that these loci may be adequate for parentage analysis and to implement ex situ genetic management plans.
Assuntos
Conservação dos Recursos Naturais , Galliformes/genética , Repetições de Microssatélites/genética , Alelos , Animais , Loci Gênicos , HeterozigotoRESUMO
The identification of ecological and evolutionary mechanisms that might account for the elevated biotic diversity in tropical forests is a central theme in evolutionary biology. This issue is especially relevant in the Neotropical region, where biological diversity is the highest in the world, but where few studies have been conducted to test factors causing population differentiation and speciation. We used mtDNA sequence data to examine the genetic structure within white-backed fire-eye (Pyriglena leuconota) populations along the Tocantins River valley in the south-eastern Amazon Basin, and we confront the predictions of the river and the Pleistocene refuge hypotheses with patterns of genetic variation observed in these populations. We also investigated whether these patterns reflect the recently detected shift in the course of the Tocantins River. We sampled a total of 32 individuals east of, and 52 individuals west of, the Tocantins River. Coalescent simulations and phylogeographical and population genetics analytical approaches revealed that mtDNA variation observed for fire-eye populations provides little support for the hypothesis that populations were isolated in glacial forest refuges. Instead, our data strongly support a key prediction of the river hypothesis. Our study shows that the Tocantins River has probably been the historical barrier promoting population divergence in fire-eye antbirds. Our results have important implications for a better understanding of the importance of large Amazonian rivers in vertebrate diversification in the Neotropics.
Assuntos
DNA Mitocondrial/genética , Passeriformes/genética , Rios , Animais , Biodiversidade , Evolução Biológica , Brasil , Ecossistema , Feminino , Variação Genética , Filogeografia , Clima TropicalRESUMO
O ácaro rajado é uma das pragas mais importantes em culturas no Brasil. O uso do controle químico de forma descontrolada leva a sérias consequências, como a presença de resíduos em frutos e surgimento de populações resistentes. Faz-se necessário o uso de alternativas de manejo do ácaro, como o controle biológico, que vem sendo utilizado como ferramenta no manejo de di versas pragas de importância agrícola no mundo. Para a realização dos bioensaios, foram avaliadas 120 cepas de Bacillus thuringiensis Berliner quanto à patogenicidade para Tetranychus urticae Koch. Foram preparadas suspensões das diferentes cepas contendo 3 × 108 esporos viáveis/mL de água destilada, aplicadas em discos de folhas de feijão de porco (Canavalia ensiformes DC). Cada cepa constituiu-se em um tratamento, com 8 repetições, cada uma contendo 10 fêmeas adultas do ácaro. Os testes em condições de laboratório mostraram que a mortalidade foi significativa, variando de 6,7% (cepa LMJ7A) a 54,9% (cepas 1077B e 886F).
The two-spotted spider mite is the most important pest to Brazilian crops. The incorrect use of chemical control leads to serious consequences, such as the presence of residues in fruits and the emergence of resistant populations. There is a need for alternative methods for managing the mite, such as biological control, which has been used as a tool in the management of various pests of agricultural importance in the world. Bioassays were carried out to analyze 120 strains of Bacillus thuringiensis Berliner in regard to their pathogenicity to Tetranychus urticae Koch. Suspensions were prepared of the different strains, containing 3 × 108 spores/mL of distilled water, and applied on Jack-bean (Canavalia ensiformes DC) leaf disks. Each strain constituted a treatment, with 8 repetitions, each containing 10 adult Tetranychus urticae females. The tests in laboratory conditions showed that mortality was significantly, ranging from 6.7% (strains LMJ7A) to 54.9% (strains 1077B and 886f).
Assuntos
Bacillus thuringiensis/isolamento & purificação , Controle Biológico de Vetores , Pragas da AgriculturaRESUMO
ABSTRACT The two-spotted spider mite is the most important pest to Brazilian crops. The incorrect use of chemical control leads to serious consequences, such as the presence of residues in fruits and the emergence of resistant populations. There is a need for alternative methods for managing the mite, such as biological control, which has been used as a tool in the management of various pests of agricultural importance in the world. Bioassays were carried out to analyze 120 strains of Bacillus thuringiensis Berliner in regard to their pathogenicity to Tetranychus urticae Koch. Suspensions were prepared of the different strains, containing 3 × 108 spores/mL of distilled water, and applied on Jack-bean (Canavalia ensiformes DC) leaf disks. Each strain constituted a treatment, with 8 repetitions, each containing 10 adult Tetranychus urticae females. The tests in laboratory conditions showed that mortality was significantly, ranging from 6.7% (strains LMJ7A) to 54.9% (strains 1077B and 886f).
RESUMO O ácaro rajado é uma das pragas mais importantes em culturas no Brasil. O uso do controle químico de forma descontrolada leva a sérias consequências, como a presença de resíduos em frutos e surgimento de populações resistentes. Faz-se necessário o uso de alternativas de manejo do ácaro, como o controle biológico, que vem sendo utilizado como ferramenta no manejo de di versas pragas de importância agrícola no mundo. Para a realização dos bioensaios, foram avaliadas 120 cepas de Bacillus thuringiensis Berliner quanto à patogenicidade para Tetranychus urticae Koch. Foram preparadas suspensões das diferentes cepas contendo 3 × 108 esporos viáveis/mL de água destilada, aplicadas em discos de folhas de feijão de porco (Canavalia ensiformes DC). Cada cepa constituiu-se em um tratamento, com 8 repetições, cada uma contendo 10 fêmeas adultas do ácaro. Os testes em condições de laboratório mostraram que a mortalidade foi significativa, variando de 6,7% (cepa LMJ7A) a 54,9% (cepas 1077B e 886F).