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51.
Thiago Batista Firmato de Almeida Hilário Júnior de Almeida Renato de Mello Prado Deyvid Diego Carvalho Maranhão Lucas Sanches Politi 《Communications in Soil Science and Plant Analysis》2017,48(13):1616-1625
Soy is to one of the main crops in the world. However, there are aspects related to its management that should be explained, especially regarding its mineral nutrition, because a proper nutritional balance is associated with productivity levels. The objective of this study was to evaluate the accumulation of nutrients in the tissues related to the deficiency of nutrients and its effects on plant development. In addition, nutritional disorder symptoms were evaluated according to the deficiency of macronutrients. For this, seven treatments were evaluated. They comprised a complete nutrient solution followed by deficiency of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S) in a completely randomized design with three replications. Plant height, number of leaves, leaf area, stem diameter, relative chlorophyll content, and production of dry matter of soybean plants were evaluated. The deficiency of any macronutrient affects biometric variables, especially the production of dry matter. The nutrients that limited the most the production of dry matter were Ca>N>K>Mg>P > S. With the exception of S, all other macronutrients, when suppressed, caused nutritional disorder symptoms. The plants presented an accumulation of K > N>Ca>P>Mg>S in leaves. In the present study, soybean plants had a high nutritional requirement of K followed by N. This requires care in the development of fertilization programs in view of the essential roles these nutrients play in the life cycle of plants.
Abbreviations: N_Nitrogen; P_Phosphorus; K_Potassium; Ca_Calcium; Mg_Magnseium; S_Sulfur; DM_Dry matter; NL_number of leaves; H_plant height; SD_stem diameter; RCI_Relative chlorophyll index; AP_Aerial part; R_Roots; EP_Entire plant; DMS_significant mean difference; CV_Coefficient of variation; pH_hydrogen potential; NaOH_sodium hydroxide; HCl_hydrochloric acid. 相似文献
52.
Gabriel Henrique de Morais Fernandes Renato Farias do Valle Junior Maytê Maria Abreu Pires de Melo Silva Rafaella Gouveia Mendes Luís Filipe Sanches Fernandes António Carlos Pinheiro Fernandes Fernando António Leal Pacheco Teresa Cristina Tarlé Pissarra Marília Carvalho de Melo Carlos Alberto Valera 《Land Degradation u0026amp; Development》2023,34(6):1778-1794
Land degradation is a worldwide problem with natural and anthropogenic causes. An important anthropogenic cause of land degradation is land uses that deviate from land capability, which is the “natural” use. Despite the conscience of scientists about this issue, studies are lacking that set up a quantitative nexus between land capability and related drivers. This nexus is essential because it allows anticipating changes in the drivers that promote or recede degradation. In this study, a partial least squares–path model (PLS–PM) was used to help closing this gap. The pilot study occurred in seven Paraopeba River sub-basins located in the State of Minas Gerais (Brazil), where capability is dominated by mosaics of forests and pastures. Land capability was assessed by the ruggedness number, being inversely proportional to it. Among multiple potential drivers of land capability initially included in the model, collinearity and other consistency and performance analyses indicated the percentage of latosols and (re)forested areas, annual rainfall, and water-related processes (e.g., weathering, nutrient leaching) as prominent in the studied region. The results linked increases of latosol and forest occupation to runoff reduction [runoff = latosol × (−0.640) + forest × (−0.156) + reforestation × (−0.379)], suggesting an attenuation of erosion by these parameters, namely gully erosion that impacts on the ruggedness number and land capability in the sequel. The weathering of carbonate rocks was also related to land capability changes because the PLS–PM model exposed a relationship between the ruggedness number and products of carbonate rock dissolution: ruggedness number = alkalinity × (−0.578) + total magnesium × (0.462) + dissolved oxygen × (−0.418). In addition to highlighting processes capable of changing land capability overtime, the model equations brought attention to measures that could improve it in the region thus preventing degradation. The measures included management practices capable to raise the soil's dissolved oxygen (e.g., through aeration) or preventing soil's magnesium deficiency (e.g., through foliar sprays). The network of cause-and-effect relationships set up by the PLS–PM model was finally used to elucidate about potential land use changes that would bring capability in the Paraopeba River basin towards a better status, such as conversions to pasture land. Future work is expected to further elucidate about the benefits for land capability of specific land use changes, through the testing of expected socioeconomic development scenarios. 相似文献
53.
Denis Rogrio Sanches Alves Suzana Raquel de Oliveira Thiago Gabriel Luczinski Wilson Rogrio Boscolo Fbio Bittencourt Altevir Signor Denise Trevisoli Detsch 《Aquaculture Research》2020,51(4):1681-1688
The experiment was conducted with the aim of determining the attractability and palatability of liquid protein hydrolysates for Nile tilapia. Five experimental diets were formulated containing 5% inclusion of fishmeal (FPE; positive control), 5% inclusion of liquid protein hydrolysate of porcine mucosa (PHM), 5% inclusion of liquid protein hydrolysate of poultry (PHF), 5% inclusion of liquid fish oil (OPE) and a diet without fishmeal (negative control). Five juveniles (2.51 ± 0.13 g) were distributed in 10 L tanks, and the animals were fed five times a day, with a previous draw being made of the offered diets. The same amount of pellets was offered and the following feeding behaviours were evaluated with the aid of three‐minute footages per feeding: time to capture first pellet, number of rejections, number of approaches without capturing the pellet and number of consumed pellets. None of the observed parameters displayed significant differences (p > .05), and all diets presented negative palatability indexes in comparison to FPE. The SPE diet provided a attractability and palatability index of 6.17%, while OPE index was 2.87%, PHM 2.82% and PHF 2.74%. Both PHF and PHM reduced the final consumption of pellets in comparison to FPE in approximately 28% and 20%, respectively, although it did not present significant values. 相似文献
54.
Luana Barbosa Pires Eduardo Antonio Sanches Elizabeth Romagosa Ruy Alberto Caetano Corrêa Filho Danilo Pedro Streit Junior Rosiane Araujo Rodrigues Nass Jayme Aparecido Povh 《Aquaculture Research》2017,48(9):5104-5110
The objective of this work was to evaluate the semen characteristics of C. macropomum fish from three successive semen sample collections taken during the same reproductive cycle. Six breeders (6.4 ± 1.5 kg) induced with crude carp pituitary extract (2.5 mg kg?1) were used. Samples of semen were collected in graduated syringes after a period of 260 degree‐hours. The semen was collected from the same males in September 2014 (sample 1), December 2014 (64 days after the first collection – sample 2) and February 2015 (86 days after the second collection – sample 3). The semen volume was higher (P < 0.05) in the sample 1 (6.7 mL) and sample 2 (3.4 mL) than in the sample 3 (1.0 mL). Sperm concentration and normal sperm did not significantly differ between samples. Likewise, sperm motility, curvilinear velocity, displacement velocity, oscillation and beat cross frequency did not vary, whereas straight‐line velocity, straightness and progression were higher (P < 0.05) in sample 2 (December). In general, despite lower amounts, the semen appeared to be of good quality for all three samples collected during the same reproductive period. 相似文献
55.
Salgado JM Rodrigues BS Donado-Pestana CM dos Santos Dias CT Morzelle MC 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(4):384-390
Cupuassu (Theobroma grandiflorum) is a fruit tree native to the Brazilian Amazon. Cupuassu beans are extensively used in the Brazilian food industry. Fat
from cupuassu beans, which are a rich source of triacylglycerols and fatty acids, is used extensively in the production of
candies and confectionery in the northern and northeastern regions of Brazil. The potential use of the agro-industrial by-products
of cupuassu has only slightly been addressed by the scientific community. Often, such by-products are sources of bioactive
compounds with functional properties. Thus, the aims of this study were to characterize the use of cupuassu peel flour (CPF)
and to examine the potential of CPF as a partial replacement in the preparation of breads through various means: chemical
analyses, determination of protein digestibility, tannins, phytic acid and phenolic contents, pH, color, volume, and acceptance
tests. The results show that CPF is a potential source of dietary fiber (79.81%), mainly insoluble fiber (78.29%), and breads
made with added CPF present high dietary fiber content (5.40 and 6.15 g/100 g for inclusions with 6 and 9% CPF, respectively)
and phytochemical values. The use of this by-product did not produce substantial changes in the physical, chemical or rheological
characteristics of breads. Therefore, breads enhanced with CPF may be a convenient functional food, offering a good source
of dietary fiber and phytochemicals. Breads prepared with 6% added CPF presented an acceptable overall quality to consumers. 相似文献
56.
EOS Batista GG Macedo RV Sala MDDV Ortolan MF Sá Filho TA Del Valle EF Jesus RNVR Lopes FP Rennó PS Baruselli 《Reproduction in domestic animals》2014,49(3):448-452
In Bos taurus cattle, antimullerian hormone (AMH) has been demonstrated to have a high degree of correlation with ovarian antral follicle count and the number of healthy follicles and oocytes. To document the correlation between the plasma concentration of AMH and follicular number in Bos indicus and Bos taurus heifers, Nelore (Bos indicus, n = 16) and Holstein heifers (Bos taurus, n = 16) had their ovarian follicular waves synchronized. After synchronization, ovarian antral follicular population (AFP) was evaluated three times at 60‐day (d) intervals (T‐120 d, 120 days before plasma AMH determination; T‐60 d, 60 days before; and T0, at the time of plasma AMH determination). The plasma AMH concentration was positively correlated with the number of ovarian follicles on the day of the follicular wave emergence in Bos indicus (Nelore) and Bos taurus (Holstein) heifers at each evaluation time (p < 0.05). The AFP was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.05). Similarly, the AMH concentration was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.0001). When heifers were classified as to present high or low AFP according to the mean of the AFP within each genetic group, high‐AFP heifers presented a greater (p < 0.0001) AMH concentration than low‐AFP heifers, regardless of the genetic group. In conclusion, the AFP is positively correlated with plasma AMH concentration in both Bos indicus (Nelore) and Bos taurus (Holstein) heifers. Furthermore, Bos indicus (Nelore) heifers presented both greater plasma AMH concentrations and AFP than Bos taurus (Holstein) heifers. 相似文献
57.
Soares TS Watanabe RM Tanaka-Azevedo AM Torquato RJ Lu S Figueiredo AC Pereira PJ Tanaka AS 《Veterinary parasitology》2012,187(3-4):521-528
Rhipicephalus (Boophilus) microplus is an ectoparasite responsible for an important decrease in meat, milk and leather production, caused both by cattle blood loss and by the transmission of anaplasmosis and babesiosis. R. microplus is a rich source of serine protease inhibitors, including the trypsin inhibitors BmTI-A and BmTI-6, the subtilisin inhibitor BmSI, and the recently described thrombin inhibitor, boophilin. Boophilin is a double Kunitz-type thrombin inhibitor, with the unusual ability to form a ternary complex with a second (non-thrombin) serine proteinase molecule. The large-scale expression and purification of boophilin and of its isolated N-terminal (D1) domain in Pichia pastoris, its expression profile, and the effect of RNAi-mediated gene silencing in tick egg production are reported. Full-length boophilin and D1 were expressed at 21 and 37.5mg/L of culture, respectively. Purified boophilin inhibited trypsin (K(i) 0.65 nM), neutrophil elastase (K(i) 21 nM) and bovine thrombin (K(i) 57 pM), while D1 inhibited trypsin and neutrophil elastase (K(i) of 2.0 and 129 nM, respectively), but not thrombin. Boophilin gene silencing using RNAi resulted in 20% reduction in egg weight production, suggesting that the expression of boophilin in this life stage would be important but not vital, probably due to functional overlap with other serine proteinase inhibitors in the midgut of R. microplus. Considering our data, Boophilin could be combining with other antigen in a vaccine production for tick control. 相似文献
58.
Twenty-four beef steers (predominantly Angus x Hereford, 14 to 18 mo of age, 403 +/- 3 kg of BW), were housed and fed in individual pens for about 122 d. Twelve steers came from a herd that had been selected for growth (high growth; HG) and the other 12 from a herd with no selection program (low growth; LG). Another 6 steers (3 from each group) were slaughtered at the beginning to obtain the initial composition. All steers were fed the same corn-based diet (3.06 Mcal of ME/kg of DM, 13.6% CP) on an ad libitum basis. Two weeks before slaughter, total urine was collected for 5 d for estimation of 3-methylhistidine excretion and myofibrillar protein breakdown rates. Compared with LG steers, HG steers had less initial BW but greater final BW, DMI (7.52 vs. 6.37 kg/d), ADG (1.33 vs. 0.853 kg/d), G:F (0.176 vs. 0.133 kg/kg), ME intake (0.233 vs. 0.201 Mcal x kg of BW(0.75) x d(-1)), and retained energy (RE; 0.0711 vs. 0.0558 Mcal x kg of BW(0.75) x d(-1)); gained more fat (676 vs. 475 g/d); and tended to gain more whole body protein (100 vs. 72 g/d), with no difference in residual feed intake (RFI). Estimated net energetic efficiency of gain (k(g)) and ME for maintenance (ME(m)) did not differ between the 2 groups, averaging 0.62 and 0.114, respectively. The HG steers had greater HCW (350 vs. 329 kg), backfat (16.1 vs. 11.6 mm), and yield grades (3.53 vs. 2.80), with a similar dressing percent, KPH fat, LM area, and marbling score. Skeletal muscle protein gain (70.2 vs. 57.6 g/d) and fractional protein accretion rate (0.242 vs. 0.197%/d) tended to be greater in HG than in LG steers. Steers were classified into low (-0.367 kg/d) and high (0.380 kg/d) RFI classes. Compared with the high RFI steers, low RFI steers consumed less DM (6.61 vs. 7.52 kg/d) and ME (0.206 vs. 0.234 Mcal x kg of BW(0.75) x d(-1)) and tended to gain less fat (494 vs. 719 g/d), but were similar for initial and final BW, ADG, G:F, protein gain, HCW, dressing percent, backfat, KPH fat, LM area, marbling score, and yield grade, as well as for all observations related to myofibrillar protein metabolism. Residual feed intake may be positively [corrected] correlated with ME for maintenance. The maintenance energy requirement increased by 0.0166 Mcal x kg(-0.75) x d(-1) for each percentage increase in fractional protein degradation rate, confirming the importance of this process in the energy economy of the animal. 相似文献
59.
Otvio Mesquita de Sousa Nayara Yoshimini de Oliveira Vanessa Villanova Kuhnen Eduardo Gomes Sanches 《Aquaculture Research》2019,50(10):3009-3016
Salt‐water recirculation systems using automatic feeders are a new frontier for marine aquaculture. The definition of the feed frequency is fundamental for the correct use of automatic feeders. Different feeding frequencies (1, 3, 6, 12 and 18 times a day) using automatic feeders were evaluated in two experiments on the performance of the dusky grouper (Epinephelus marginatus) in salt‐water recirculation system. In the first experiment, three feeding frequencies were evaluated: feeding once a day; three times a day and six times a day. In the second experiment, three feeding frequencies were evaluated: feeding six times a day; 12 times a day and 18 times a day. Waters parameters (temperature, salinity, oxygen level, total ammonia, pH and oxidation‐reduction potential) were maintained at specific ranges for the species. Among all the evaluated frequencies, 12 times a day provided the best productive performance, obtaining superior results for final weight, final biomass, specific growth rate and daily weight gain. For juveniles of the dusky grouper, the ideal feeding frequency is regular feedings every 2 hours, which is impractical to run without the use of automatic feeders. 相似文献
60.