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151.
Performance and carcass characteristics of young cattle fed with soybean meal treated with tannins 下载免费PDF全文
Rafael Mezzomo Pedro Veiga Rodrigues Paulino Marcília Medrado Barbosa Taiane da Silva Martins Mario Fonseca Paulino Kaliandra Souza Alves Daiany Iris Gomes João Paulo Ismério dos Santos Monnerat 《Animal Science Journal》2016,87(6):775-782
This study aimed to evaluate the effects of replacement of soybean meal (SBM) with soybean meal treated with tannin (SBMT) on the intake, digestibility, performance and characteristics of the carcasses of young cattle fed a high‐concentrate diet. Forty‐two Nellore bulls with body weight of 244.5 ± 4.99 kg were used. Diets had the inclusion of 7.5% SBM, with a proportion of that SBM (0, 33, 66 or 100%) replaced for SBMT; and other treatment (SBMT + urea) just with 2.5% of SBM which was treated with tannins. Seven animals were randomly selected and slaughtered, and the remaining animals were distributed on treatments and remained for 112 days. After, all animals were slaughtered. There was a linear decline in dry matter intake (P = 0.026) when SBM was replaced with SBMT. No decrease in carcass weight (P > 0.05) was observed. The efficiency of carcass weight gain showed a quadratic function effect (P = 0.049). There were changes in carcass gain composition when SBMT was added (P < 0.05), with an increase in muscle and reduction in fat deposition. The use of SBMT in place of SBM causes changes in body gain composition in animals and reduces DM intake by the animals, achieving a better feed conversion efficiency. 相似文献
152.
Carolina Gonzales da Silva Carlos Frederico Martins Heidi Christina Bessler lvaro Moraes da Fonseca Neto Tereza Cristina Cardoso Maurício Machaim Franco Anelise dos Santos Mendona Ligiane de Oliveira Leme Jos Renato Junqueira Borges Juaci Vitoria Malaquias Snia Nair Bo 《Reproduction in domestic animals》2019,54(2):289-299
The aim of this work was to investigate the methylation and hydroxymethylation status of mesenchymal stem cells (MSC) from amniotic fluid (MSC‐AF), adipose tissue (MSC‐AT) and fibroblasts (FIB‐control) and to verify the effect of trichostatin A (TSA) on gene expression and development of cloned bovine embryos produced using these cells. Characterization of MSC from two animals (BOV1 and BOV2) was performed by flow cytometry, immunophenotyping and analysis of cellular differentiation genes expression. The cells were used in the nuclear transfer in the absence or presence of 50 nM TSA for 20 hr in embryo culture. Expression of HDAC1, HDAC3 and KAT2A genes was measured in embryos by qRT‐PCR. Methylation results showed difference between animals, with MSC from BOV2 demonstrating lower methylation rate than BOV1. Meanwhile, MSC‐AF were less hydroxymethylated for both animals. MSC‐AF from BOV2 produced 44.92 ± 8.88% of blastocysts when embryos were exposed to TSA and similar to embryo rate of MSC‐AT also treated with TSA (37.96 ± 15.80%). However, when methylation was lower in FIB compared to MSC, as found in BOV1, the use of TSA was not sufficient to increase embryo production. MSC‐AF embryos expressed less HDAC3 when treated with TSA, and expression of KAT2A was higher in embryos produced with all MSC and treated with TSA than embryos produced with FIB. The use of MSC less methylated and more hydroxymethylated in combination with embryo incubation with TSA can induce lower expression of HDAC3 and higher expression of KAT2A in the embryos and consequently improve bovine embryo production. 相似文献
153.
Gabriela Cardoso Dal Pont Emanuele Cristiny Goes Kariny Fonseca da Silva Simone Gisele de Oliveira Chayane da Rocha Alex Miorka 《Journal of animal physiology and animal nutrition》2019,103(5):1453-1461
Glycerol is one of the substrates used for glycogen production by the chicken embryo, which is the predominant energy source during the last days of incubation and during hatching. The objective of the present study was to evaluate the in ovo feeding (IOF) of glycerol in the light and heavy broiler eggs derived from breeders of two different ages. Two experiments, with 672 eggs each, were carried out. The only difference between the experiments was breeder age: 32 weeks old in Exp. I and 60 weeks old in Exp. II. A completely randomized experimental design in a 3 × 2 factorial arrangement was applied. Treatments consisted of three glycerol IOF doses (0, 6, or 12 mg/ml) and two egg weights (light or heavy). Incubation parameters, glycogen reserves and live performance parameters (1–7 days of age) were evaluated. Hatch of fertile eggs, embryo mortality after IOF and the number of early‐hatching chicks were not affected by the treatments in both experiments. Hatchlings from heavy eggs (68.03 ± 0.64 g) laid by young breeders and receiving 6 mg glycerol/ml showed higher liver glycogen levels than those injected with 0 or 12 mg/ml. Glycerol IOF of embryos from young breeders increased feed intake and weight gain at 7 days of age, independently of egg weight. However, different glycerol dosages had no effect on the performance of the progeny of 60‐week‐old breeders. These results show that glycerol may be used as an IOF ingredient without affecting incubation parameters. The chickens from young breeders had greater glycogen deposition with inoculation of 6 mg/ml of glycerol and better performance with glycerol administration. However, glycerol IOF did not improve the performance of the progeny of 60‐week‐old breeders. Therefore, glycogen IOF may be recommended for eggs laid by young breeders. 相似文献
154.
155.
Fernando Manuel Monteiro Maria Madalena Fonseca Manuel Armando Madeira Adrien J. Herbillon 《植物养料与土壤学杂志》2012,175(1):94-100
An evaluation of the factors determining the occurrence and the properties of soils with low permeability occurring in vast areas in S Portugal was carried out taking into account the terrain morphology and the geology of the region. This paper deals with the variation patterns of the physical and chemical characteristics of soils from several soil toposequences that occur under different gradient slopes and on different parent rocks. Spatial variation of soil properties mainly depends on the composition of their cation‐exchange complex, as the role of other factors, such as the mineralogy of the clay fraction, were of minor importance. There is often a stronger increment of Na and/or Mg than of Ca with depth, causing a variable degree of sodicity in some of these soils, to which waterlogging tendency of their upper horizons is related. Though the occurrence of these features is determined by the nature of the parent rock, their degree of expression varies primarily according to the topographic position of soils. Therefore, a catenary distribution including nonsodic Cambisols or Luvisols in the hillcrests and Stagnic Solonetz or Sodic Luvisols or Sodic Stagnosols in the topographic lows is common. Such soil characteristics are of utmost importance for irrigation suitability and management of these soils, and for environmental impacts assessment, as the region is vulnerable to desertification. 相似文献
156.
Sara C. Pé-Leve Santos Mariana Eloy Cruz António M. E. Barroso Catarina P. S. Fonseca Mauro Guerra Maria Luísa Carvalho José Paulo Santos 《Journal of Soils and Sediments》2014,14(4):778-784
Purpose
Mining activities represent a current source of pollution due to the large release of trace elements from mineral particles into the soil, atmosphere, and ecosystems. In active or abandoned metal-mining areas, direct discharge from mining deposits is one of the most common processes of contamination.Materials and methods
In this work, we calculated the elemental concentrations of plants, edible for cattle, which might contain high values of toxic elements, such as As, Cu, Zn, and W, originated from mining exploitation, especially wolframite. Several species of plants originating from the same contaminated place, close to the mine, were the subject of our study in order to compare the uptake of harmful elements, from the contaminated soils, in the different plants. We have used the energy-dispersive X-ray fluorescence technique to perform the analysis and quantification of the elements present in the collected samples. The quantification was based on the fundamental parameters method for plants and on the WinAxil compare mode using a standard reference material, for soils. Calibration against a series of standard samples has been carried out.Results and discussion
A comparison between contaminated and control samples, within the same species, was performed. The contamination of the two mining wash sites is assessed by comparing the elemental concentration of several plants in these places. Elemental content in soils was investigated, and a comparison between elemental levels in plants was performed.Conclusions
High concentrations of tungsten were found near the new wash site. Arsenic was found throughout the area in concentrations many times higher than those recommended by the World Health Organization. 相似文献157.
Larissa Alves Guimar?es Paula Christine Jimenez Thiciana da Silva Sousa Hozana Patrícia S. Freitas Danilo Damasceno Rocha Diego Veras Wilke Jesús Martín Fernando Reyes Otília Deusdênia Loiola Pessoa Letícia Veras Costa-Lotufo 《Marine drugs》2014,12(12):5839-5855
The present study highlights the biological effects of chromomycin A2 toward metastatic melanoma cells in culture. Besides chromomycin A2, chromomycin A3 and demethylchromomycin A2 were also identified from the extract derived from Streptomyces sp., recovered from Paracuru Beach, located in the northeast region of Brazil. The cytotoxic activity of chromomycin A2 was evaluated across a panel of human tumor cell lines, which found IC50 values in the nM-range for exposures of 48 and 72 h. MALME-3M, a metastatic melanoma cell line, showed the highest sensitivity to chromomycin A2 after 48h incubation, and was chosen as a model to investigate this potent cytotoxic effect. Treatment with chromomycin A2 at 30 nM reduced cell proliferation, but had no significant effect upon cell viability. Additionally, chromomycin A2 induced accumulation of cells in G0/G1 phase of the cell cycle, with consequent reduction of S and G2/M and unbalanced expression of cyclins. Chromomycin A2 treated cells depicted several cellular fragments resembling autophagosomes and increased expression of proteins LC3-A and LC3-B. Moreover, exposure to chromomycin A2 also induced the appearance of acidic vacuolar organelles in treated cells. These features combined are suggestive of the induction of autophagy promoted by chromomycin A2, a feature not previously described for chromomycins. 相似文献
158.
Bursaphelenchus fungivorus is reported for the first time in Portugal, identified as associated with Pinus pinaster bark and characterized on the basis of morphological and morphometrical characters for this species. Species identification was confirmed using restriction fragment length polymorphism analysis and sequencing of the internal transcribed spacer (ITS) regions of ribosomal DNA. Intraisolate genetic variability was detected among ITS sequences of the Portuguese B. fungivorus isolate. Phylogenetic analysis, obtained from multiple sequence alignment between ITS sequences of Bursaphelenchus species, revealed that the Portuguese B. fungivorus isolate clusters with other B. fungivorus isolates, forming a separate group close to B. seani highlighting a molecular proximity of these two species. 相似文献
159.
Jan Schwarzbauer Sven Sindern Larissa Dsikowitzky Gerd Liebezeit 《Journal of Soils and Sediments》2010,10(1):104-118
Purpose
The immediate time period after the Second World War (1945–1946) was characterised by an urgent need to dispose large amounts of ammunition residues. Although the environmental relevance of explosives released to soils is intensively investigated, to date, their fate and effects in marine ecosystems are not well known. Surface sediments from Lake Bant, Germany, for which deposition of an enhanced amount of ammunition after World War II has been reported, were analysed to identify organic and inorganic indicators for warfare residues. Additionally, samples of ammunition residues collected from the Wadden Sea, Germany, were analysed in order to obtain information on the long-term behaviour of explosives in undamaged ammunition left in the aquatic environment and to obtain first insights into the spectrum of organic substances which are possibly released to the aquatic environment by such ammunition residues. 相似文献160.
A. M. de Paula A. F. da Fonseca E. J. B. N. Cardoso A. J. Melfi 《Water, air, and soil pollution》2010,205(1-4):161-171
Agricultural reuse of treated sewage effluent (TSE) is an environmental and economic practice; however, little is known about its effects on the characteristics and microbial function in tropical soils. The effect of surplus irrigation of a pasture with TSE, in a period of 18 months, was investigated, considering the effect of 0% surplus irrigation with TSE as a control. In addition, the experiment consisted of three surplus treatments (25%, 50%, and 100% excess) and a nonirrigated pasture area (SE) to compare the soil microbial community level physiological profiles, using the Biolog method. The TSE application increased the average substrate consumption of the soil microbial community, based on the kinetic parameters of the average well color development curve fitting. There were no significant differences between the levels of surplus irrigation treatments. Surplus TSE pasture irrigation caused minor increases in the physiological status of the soil microbial community but no detectable damage to the pasture or soil. 相似文献