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221.
Priscila Teixeira de Souza Maria Gorete Flores Salles Antônio Nélson Lima da Costa Hilton Alexandre Vidal Carneiro Leonardo Peres de Souza Davide Rondina Airton Alencar de Araújo 《International journal of biometeorology》2014,58(7):1559-1567
The aim of this work was to determine the adaptability of Saanen and ½Saanen?×?½Anglo-Nubian (½S½AN) goats bred in tropical climates. The study included 30 goats, 15 Saanen and 15 ½S½AN. The data was collected during the rainy and dry seasons. During the whole experimental period, the environment variables were recorded, as well as rectal temperature (RT), superficial temperature (ST), respiratory rate (RR) and heart rate (HR) and milk production (MP). The adaptability coefficient (AC) was calculated for both genotypes. The averages were evaluated by ANOVA at 5 % probability. There was a genotype and period of year effect, as well as the interaction genotype?×?period of year. Pearson's simple correlation analysis was then carried out between milk production and physiological and environment variables. There was a statistical difference (p?0.05) between the seasons for RT, ST and RR. RT, RR and HR were lower for ½S½AN than Saanen goats, regardless of the season. MP was greater in the dry season (p?0.05) (2.52?±?0.50 kg/day for ½S½AN and 2.41?±?0.38 kg/day for Saanen) than the rainy season (2.17?±?0.27 kg/day for ½S½AN and 2.28?±?0.53 kg/day for Saanen). The MP correlations were very significant (p?0.05), however low and negative, where it was higher when correlated with RR in Saanen goats. Under the conditions of the present study, it is concluded that the goats were influenced by climatic factors, where the rainy period was more likely to cause thermal stress in the animals. 相似文献
222.
Ulysses Paulino de Albuquerque Thiago Antonio de Sousa Araújo Marcelo Alves Ramos Viviany Teixeira do Nascimento Reinaldo Farias Paiva de Lucena Júlio Marcelino Monteiro Nélson Leal Alencar Elcida de Lima Araújo 《Biodiversity and Conservation》2009,18(1):127-150
Ethnobotany is a relatively new discipline but its social and scientific roles are becoming more consistently defined and
its importance as a tool for complimenting management and conservation strategies at local and regional levels is now well
recognized by the scientific community throughout the world. In the present work we have collected information from four years
of ethnobotanical study in an area of caatinga vegetation in the semi-arid region of northeastern Brazil with the goal of defining a model for conservation and management
actions in the region. Drawing on ethnobotanical and ecological information obtained through traditional techniques of ethnobotanical
and vegetation surveys, we discuss the uses of 166 native and exotic plant species and suggest specific actions and specific
groups of species for conservation and sustainable use programs. We also discuss the limitations of our approach and indicate
what information must still be collected in order to construct robust and workable plans of action. 相似文献
223.
The noctuid moth Spodoptera frugiperda consists of two strains associated with different larval host plants (most notably corn and rice). These strains exhibit differential temporal patterns of female calling and copulation during scotophase, with the corn strain more active earlier in the night. We investigated strain‐specific constraints in reproductive timing, mating interactions between the two strains, and the mode of inheritance of timing of female calling, male calling, copulation and oviposition. We observed an allochronic shift of all reproductive behaviours by approximately 3 h and a parallel shift of nonreproductive locomotor activity, suggesting involvement of the circadian clock. The corn strain was more variable in the timing of calling and copulation than the rice strain. Rice strain females were more restricted in the timing of copulation than rice strain males, while such differences between the sexes were not apparent in the corn strain. There were significant interactions between the strains affecting onset times of copulation and male calling. The four investigated reproductive traits differed in their modes of inheritance: timing of female and male calling exhibited strong maternal effects, timing of copulation was controlled by a combination of maternal effects and corn strain dominant autosomal factors, and timing of oviposition was inherited in a corn strain dominant fashion. We conclude that the allochronic separation of reproduction between fall armyworm strains is asymmetric, less pronounced than previously thought, and under complex genetic control. 相似文献
224.
The Inclusion and Selection of Medicinal Plants in Traditional Pharmacopoeias—Evidence in Support of the Diversification Hypothesis 总被引:1,自引:0,他引:1
Nélson Leal Alencar Thiago Antonio de Sousa Araújo Elba Lúcia Cavalcanti de Amorim Ulysses Paulino de Albuquerque 《Economic botany》2010,64(1):68-79
The Inclusion and Selection of Medicinal Plants in Traditional Pharmacopoeias—Evidence in Support of the Diversification Hypothesis. An ethnobotanical study with phytochemical analyses was undertaken to examine the medicinal plants used by residents of a
small rural community in northeastern Brazil. The present work tested two ideas that attempt to explain the inclusion and
selection of medicinal plants in a given culture: the diversification hypothesis and the concept of versatility. The study
involved 101 people and used semistructured interviews. A total of 61 plants were selected, including 25 exotic and 36 native
species. Plants were classified according to their habit and analyzed for their phytochemical components. In addition, the
relative importance (RI) of these plants was calculated, and a chemical diversity index (CDI) was created and applied to each
of the species. Exotic and native plants were found to have significantly different occurrences of certain classes of compounds;
this result supports the diversification hypothesis. It was therefore concluded that exotic plants are included in traditional
pharmacopoeias to fill therapeutic vacancies that native plants cannot satisfy. 相似文献
225.
Veneroni-Gouveia G Meirelles SL Grossi DA Santiago AC Sonstegard TS Yamagishi ME Matukumalli LK Coutinho LL Alencar MM Oliveira HN Regitano LC 《Animal genetics》2012,43(5):518-524
Backfat thickness affects the preservation of the beef carcass after slaughter and confers organoleptic characteristics assessed by the consumer. One of the breeding goals for Canchim, a tropically adapted breed, is to comprehensively increase fat thickness. Our goals were to identify genomic regions associated with backfat in Canchim populations and validate the association of single nucleotide polymorphisms (SNPs) overlapping previously identified QTL regions known to affect fat deposition. Fifteen animals with lower and 15 animals with higher residues for backfat, according to a linear model using the SAS GLM procedure, were selected from a population of 1171 animals and genotyped using the BovineSNP50 BeadChip. Initial analysis revealed more than 100 SNPs that discriminated the tails of phenotypic distribution. One extended region of association included the centromeric region of chromosome (Chr) 14. Because this region overlapped with QTL from previous reports, we developed SNP assays to interrogate two linkage disequilibrium blocks, one in the centromeric region and another in the middle region of Chr 14 to confirm the association. The analysis validated the presence of specific haplotypes affecting fat thickness. 相似文献
226.
Meirelles SL Gouveia GV Gasparin G Alencar MM Gouveia JJ Regitano LC 《Genetics and molecular research : GMR》2011,10(2):1220-1226
Investigation of molecular marker effects on production traits is essential to define marker assisted selection strategies in beef cattle. We looked for a possible association of molecular markers and backfat thickness (BFT) and rib eye area (REA) in Canchim (5/8 Charolais + 3/8 Zebu) and MA (offspring of Charolais bulls and 1/2 Canchim + 1/2 Zebu cows) animals raised exclusively on pasture. Traits were measured on 987 individuals from seven herds from two Brazilian States (S?o Paulo and Goiás), in March and April from 2005 to 2007, when animals were, on average, 19 months of age. Five microsatellite markers lying in QTL regions for BFT and REA (BMS490 and ETH10 on chromosome 5, INRA133 and ILSTS090 on chromosome 6, and BMS2142 on chromosome 19) were genotyped and association analyses were performed under an animal model using the restricted maximum likelihood method. After correction for multiple tests, a significant effect of microsatellite BMS490 on REA was observed, suggesting that at least one QTL affecting carcass traits in this region of the BTA5. No significant effect on BFT was observed for these markers. 相似文献
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229.
Jorddy Neves Cruz Kauê Santana da Costa Tarcísio André Amorim de Carvalho Nelson Alberto Nascimento de Alencar 《Journal of biomolecular structure & dynamics》2020,38(5):1425-1434
AbstractCongenital adrenal hyperplasia is an inherited autosomal recessive disorder related to deficient cortisol synthesis. The deficiency of steroid 21-hydroxylase (cytochrome P450 21A2), an enzyme involved in cortisol synthesis, is responsible for ~95% of cases of congenital adrenal hyperplasia. This metabolic disease exhibits three clinical forms: salt-wasting, simple virilizing, and non-classical form, which are divided according to the degree of severity. In the present study, structural and mutational analyses were performed in order to identify the structural impact of mutations on cytochrome P450 21A2 and correlate them with patient clinical severity. The following mutations were selected: arginine-356 to tryptophan (R356W), proline-30 to leucine (P30L), isoleucine-172 to asparagine (I172N), valine-281 to leucine (V281L), and the null mutation glutamine-318 (Q318X). Our computational approach mapped the location of residues on P450 and identified their implications on enzyme electrostatic potential mapping to progesterone and heme binding pockets. Using molecular dynamics simulations, we analyzed the structural stability of ligand binding and protein structure, as well as possible conformational changes at the catalytic pocket that leads to impairment of enzymatic activity. Our study sheds light on the impact structural mutations have over steroid 21-hydroxylase structure-function in the cell.Communicated by Ramaswamy H. Sarma 相似文献