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51.
Saulo da Luz e Silva Paulo Roberto Leme Soraia Marques Putrino Anglica Simone Cravo Pereira Amaury Camilo Valinote Jos Carlos Machado Nogueira Filho Dante Pazzanese Duarte Lanna 《Livestock Science》2009,122(2-3):290-295
The purpose of this work was to evaluate the fatty acid composition of the Longissimus muscle from carcasses of Nellore steers fed diets with calcium salts of fatty acids (CSFA) and high moisture corn. Forty eight steers were fed during 70 days four diets containing dry corn (DC), high moisture corn (HM), dry corn plus CSFA (DC-CSFA) or high moisture corn plus CSFA (HM-CSFA). Fatty acid composition of the Longissimus muscle was determined by gas chromatography. Corn type had no effect on the ether extract percentage and in the content of the majority of the fatty acids, although steers fed HMC showed higher levels of polyunsaturated fatty acids and polyunsaturated/saturated ratio. Feeding CSFA increased ether extract percentage but had no effect on total of saturated, unsaturated and saturated: unsaturated ratio. Both high moisture corn and calcium salts of fatty acids increased CLA (cis9, trans11) and total CLA concentrations in intramuscular fat. 相似文献
52.
A multiplex PCR assay for differentiating strongyle eggs from cattle has recently been described; however, the egg disruption and DNA extraction procedures, though effective, are inadequate for large studies or clinical application. The purpose of this research was to evaluate methods for disrupting trichostrongyle eggs, then assess commercial kits for extracting egg DNA using Ostertagia ostertagi as a model species. Egg disruption procedures tested included probe sonication, bath sonication, bead beating, boiling, microwaving, proteinase K/SDS digestion, freezing, and various combinations of the above with the incorporation of sodium dodecyl sulfate. These procedures were evaluated in conjunction with four commercial DNA extraction kits: DNA Stool mini kit and DNeasy Plant kit (Qiagen), Fast DNA kit (QBiogene), and the MAP extraction kit (Tetracore). Results showed that egg disruption was best accomplished with the bead beater and ceramic beads, resulting in 100% disruption within 1min. When DNA extraction was preceded by the isolation of eggs from feces, all procedures except the Fast DNA kit produced PCR-ready DNA from at least two eggs. The DNeasy Plant kit allowed consistent detection of DNA released from one egg. Due to the morphological similarities among trichostrongyle eggs in ruminants, strongyle eggs in equids, and hookworm eggs, the methods described herein may have broad application to other nematodes. 相似文献
53.
Delphine Sciama Laurent Augusto Jean-Luc Dupouey Maya Gonzalez Concepción Moares Domínguez 《Forest Ecology and Management》2009
The aim of this work was to investigate differences in soil chemistry and understory composition between recent forests (sites afforested in the last 170 years) and ancient forests growing on non-acidic soils. The study was carried out on hardwood forests at moderate elevation (400–600 m asl) in the Jura Mountains (N.E. France) on four main pedological substrates with different characteristics. The floristic composition of 127 stands from recent forests (n = 65) or ancient forests (n = 62) was surveyed. Some functional traits and the Ellenberg indicator values of the surveyed species were recorded. In addition, the topsoil from 30 stands was analysed. The composition of the flora was analysed by Detrended Correspondence Analysis and the species which were typical of one class of forest age were identified using a chi-square (χ2) test. The difference between forest classes for plant traits, their indicator values, or soil chemistry was tested using the generalized linear model and Bonferroni t-tests (or Kruskall–Wallis tests). The floristic composition of the ancient forests was significantly different from that of the recent forests and was characterized by a high occurrence of shrub species in recent forests. These differences were associated with higher specific leaf area, low-range seeds dispersal, and some life forms like geophytes. There was no clear difference in soil chemistry between the two classes of forests, except for δ15N values. The weakness of the difference in the soil between ancient and recent forests suggested that changes in soil chemistry caused by a former agricultural land use were not responsible for the differences in understory composition recorded. The differences in functional traits between the two forest classes supported this conclusion. We finally concluded that (i) past land use modifies the vegetation composition of current forests, even on neutral soils and that (ii) in our context, biological filters were probably responsible for these changes. 相似文献
54.
Eduardo Antônio Sanches Giovano Neumann César Pereira Rebechi de Toledo Robie Allan Bombardelli Pitágoras Augusto Piana Elizabeth Romagosa 《Aquaculture Research》2013,44(4):534-541
The aim of this work was to evaluate the spermatic parameters of jundia, Rhamdia quelen, semen stored for short periods under different temperatures. Fifteen males were used in a time factorial experimental design (13 × 3 × 3 × 3). The sperm was stored at: 15; 25 and 35°C and activated in water at: 15; 25 and 35°C each, respectively, within storage periods of: 0; 2; 4; 6; 8; 10; 12; 16; 20; 24; 32; 40 and 48 h after collection. The treatments were performed in triplicates and in sequential protocols every 50 h. The motility parameters were evaluated using Pearson's correlation analysis and the significant parameters (P < 0.05) were summarized using principal component analysis forming two predicted groups. Group 01 composed the following parameters: curvilinear velocity, wobble and linearity; group 02 comprised average path velocity, straight line velocity, beating cross frequency and motility rate. Effects (P < 0.05) of treatments were observed only in group 02, with interaction between time and temperature of exposure and between exposure time and water temperature. Superior results of spermatic parameters of group 02 were observed right after collection. However, the exposure and spermatic activation at 15°C assured significant results 48 h after collection when compared with 25 and 35°C. 相似文献
55.
Caique Carvalho Medauar Samuel de Assis Silva Luis Carlos Cirilo Carvalho Rafael Augusto Soares Tibúrcio Julião Soares de Souza Lima Paullo Augusto Silva Medauar 《Journal of Sustainable Forestry》2018,37(7):739-752
This study evaluated the effectiveness of chemical control for eradicating eucalyptus sprouts using images obtained with Unmanned Aerial Vehicle (UAV). The study was carried out in eucalyptus plantations in Itabela, BA, in replanting areas during pre-planting application of herbicide. Aerial images obtained by a UAV were used to evaluate the effectiveness of the herbicide application for sprouts control. After the images were acquired, they were processed to calculate the normalized difference vegetation index (NDVI) and submitted to a supervised classification to quantify the percentage reduction of sprout green matter. The percentage data were submitted to analysis of variance and the means were compared by Tukey test at 5%. The differences, both visual and average percentages were observed only during the evaluation period with no evident effect of the treatments on sprout control. The images provided by the UAV allowed to monitor and identify visually the plots where biomass reduced or increased and to evaluate the effectiveness of chemical control of eucalyptus sprouts, indicating areas where it was nonexistent, partial or total. 相似文献
56.
Leonel Lopez-Toledo Margarita Heredia-Hernández Dante Castellanos-Acuña Arnulfo Blanco-García Cuauhtémoc Saénz-Romero 《New Forests》2017,48(6):867-881
Climate varies along altitudinal gradients and species performance may be affected in response to these variations. Climate change can modify these gradients and, at the lower limit of species distributions, individuals may become stressed and their general health and reproductive performance may decrease. Study and prediction of the effects of climate change on the distribution of species along these gradients is therefore necessary. Our model study species, Pinus pseudostrobus, is a widely distributed pine in Mexico, ranging from 1600 to 3200 masl in altitude. In order to explore changes in health condition and reproductive investment along an altitudinal gradient, ten reproductive trees were selected in each of four populations (at 2300, 2400, 2700 and 2900 masl). As a proxy of individual health, we conducted a rapid visual assessment for each tree, based on crown defoliation, dead branches and foliage discoloration. This stress condition index (SCI) ranges from zero to fifteen, and lower values indicate low stress and therefore better health conditions. We also evaluated reproductive (cone weight, number/weight of seeds) and progeny (germination/seedling growth) traits. In addition, the relationships between SCI and the reproductive/progeny traits were assessed. The lowest altitude population presented poor health, with higher values of SCI (mean ± SE = 6.3 ± 0.9) that reduced up to 4.8-fold in higher-altitude populations. Cone weight also differed among altitudes, with lighter cones in the lower population (mean ± SE = 38.2 ± 4.3 g), and 1.5-fold heavier cones found in the higher populations. In general, all of the reproductive/progeny traits differed among altitudes. The population of intermediate altitude (2700 masl) presented the highest values for all traits evaluated, indicating higher performance at this altitude. Finally, a negative relationship was found between stress condition and cone weight. Based on our results and climate change models and their predictions, an increase in physiological stress can be expected in individuals of low altitude populations. Furthermore, possible increases in pests and pathogens are likely to contribute to the decline of this population. It is therefore necessary to maintain efforts of stress condition assessment and population dynamics, as well as to permanently monitor the climate along altitudinal gradients. 相似文献
57.
José Zilton Lopes Santos Bruno Fernando Faria Pereira José Augusto Figueira da Silva Carlos Alberto Franco Tucci Sílvio Vieira da Silva Tainah Manuela Benlolo Barbosa 《Communications in Soil Science and Plant Analysis》2017,48(11):1280-1290
We evaluated the effects of macronutrient and micronutrient omission, and of liming, on Jatropha curcas (JC) in greenhouse study. The experimental design was a factorial combination of 2 liming treatments (nil or 4.5 t. ha?1 of dolomitic lime) x 7 combinations of fertility status, with five replications. The concentrations and uptake of nutrients by JC plants follow the order: nitrogen > potassium > calcium ≥ Magnesium > sulfur > phosphorus > iron > boron > manganese > zinc > copper (N > K > Ca ≥ Mg > S > P > Fe > B > Mn > Zn > Cu), but the growth of JC plants was negatively affected mainly by omission of macronutrients, in the following order: P > N = K = S, on limed soil. Phosphorus is the most critical element for development. JC is responsive to micronutrients only when applied together with macronutrients. Potassium chloride is not recommended as K+ source for JC crop. Lime is recommended to improve growth and nutritional status of JC plants. 相似文献
58.
Hernández Juan Augusto Lepe Marissa Macedo Rafael Arredondo Victalina Cortez Carlos Eliseo García Luis Jorge Prado Omar 《Tropical animal health and production》2017,49(1):173-178
Tropical Animal Health and Production - A study was conducted with the objective to characterize the morphology of Socorro Island Merino sheep. A total of 67 sheep, 62 females, 26 purebred and 36... 相似文献
59.
Carlos Alberto Scapim Cleso Antônio Patto Pacheco Antônio Teixeira do Amaral Júnior Rafael Augusto Vieira Ronald José Barth Pinto Thiago Vincenzi Conrado 《Euphytica》2010,174(2):209-218
In plant breeding, correlations between the statistics of stability and adaptability of popcorn cultivars are not yet well
understood. Therefore, the objectives of the present experiment was to investigate the correlations between sdi2 \sigma_{\rm di}^{2} and bi \beta_{\rm i} from Eberhart and Russell, ωi from Wricke,
\textS\texti(1) {\text{S}}_{\text{i}}^{(1)} ,
\textS\texti(2) {\text{S}}_{\text{i}}^{(2)} and
\textS\texti(3) {\text{S}}_{\text{i}}^{(3)} from Huehn, Pi from Lin and Binns and the rank-sum from Kang, and indicate the most reliable method for selecting popcorn cultivars. These
statistics were estimated by data of crop yield from 19 Brazilian genotypes under 21 environments and popping expansion under
16 environments. The ωi,
\textS\texti(1) {\text{S}}_{\text{i}}^{(1)} ,
\textS\texti(2) {\text{S}}_{\text{i}}^{(2)} ,
\textS\texti(3) {\text{S}}_{\text{i}}^{(3)} and sdi2 \sigma_{\rm di}^{2} were positively and significantly correlated indicating that just one in these five statistics is sufficient for selecting
stable genotypes although they were not correlated with the means of crop yield and popping expansion. The bi \beta_{\rm i} was negatively and significantly correlated with Pi for crop yield indicating that the most adaptable genotypes tend to have the lowest estimates of Pi. Although Pi was not correlated with ωi,
\textS\texti(1) {\text{S}}_{\text{i}}^{(1)} ,
\textS\texti(2) {\text{S}}_{\text{i}}^{(2)} ,
\textS\texti(3) {\text{S}}_{\text{i}}^{(3)} , or sdi2 \sigma_{\rm di}^{2} statistics, it displayed positive correlation with the Index 1 (crop yield and popping expansion +
\textS\texti(1) {\text{S}}_{\text{i}}^{(1)} rank) and Index 2 (crop yield and popping expansion + Wi) indicating that superior popcorn genotypes are also stable. Finally, both Pi and the rank-sum are useful statistics in breeding programmes where crop yield, popping expansion and stability are essential
traits for selecting genotypes. 相似文献
60.
Dante Augusto Blauth Jorge Ricardo Ducati 《Computers and Electronics in Agriculture》2010,71(2):182-188
A Web-based system is presented, integrating spatial information from remote sensing images, GPS measurements and inventory data. Monitoring, research and management of the grape production at Rio Grande do Sul State, Brazil (624,000 metric tons in 2006) can be done through a system entirely based in open-source codes. Information from three different sources are integrated: Information on production comes from the State’s Viticultural Inventory, detailing the regional yearly grape production; positional information comes from field GPS measurements of vine parcels and the system’s capabilities of making maps; imagery information comes from aerial or satellite images. Further capabilities on image classification leads to the identification of vine areas; this allows crossing this data with information provided by owners. This system allows both the monitoring of grape production for administrative purposes and investigations either on regional land and soil cover, or in other applications derived from image classification. The system concept can be readily extended to other applications in land use monitoring. 相似文献