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991.
Souza Shenia O. Oliveira Luciana C. Cavagis Alexandre D. M. Botero Wander G. 《Water, air, and soil pollution》2014,225(12):1-13
Treated and untreated rice straw extensively exists in the soil. In order to elucidate its possible effect on the fate of organic pollutants, sorption of pyrene by rice straw and its main constituents (lignin, cellulose, and hemi-cellulose) were studied, as single solute and in the presence of other co-existing organic pollutants, phenanthrene (Phen), benzo[a]pyrene (BaP), phenol, and pentachlorophenol (PCP). Pyrene showed the greatest sorption on lignin with greater aromaticity and smaller polarity, and the sorption coefficient was almost two orders of magnitude greater than those on cellulose and hemi-cellulose. Bi-solute sorption results showed that Phen, BaP and PCP exhibited apparent competitive sorption with pyrene on the four sorbents; while the existence of phenol promoted the sorption of pyrene on rice straw and lignin but inhibited the sorption on cellulose and hemi-cellulose. For the two polycyclic aromatic hydrocarbon (PAH) co-solutes and PCP, hydrophobicity and molecular size played important roles in competition, suggesting the direct competition for hydrophobic sorption sites and pore blockage mechanisms. In contrast, the polar co-solute, phenol showed different effects on pyrene sorption onto the four sorbents, suggesting that multiple interactions between polar organic compounds and sorbents are involved in the sorption. 相似文献
992.
993.
994.
da Costa Christiane Almeida Veloso Josiene Silva de Oliveira Bruno Ferreira Lourenço Valdir Reis Ailton 《植物病害和植物保护杂志》2021,128(1):317-321
Journal of Plant Diseases and Protection - Mulberry (Morus spp.), represents a set of plants grown in Brazil for production of fruits, leaves for feeding silkworms and ruminant animals, and for... 相似文献
995.
Jitender Prakash Dubey Sarah Jane Casey Anne Marie Zajac Stephen Arthur Wildeus David Scott Lindsay Shiv Kumar Verma Solange Oliveira Oliver Chun Hung Kwok Chunlei Su 《Tropical animal health and production》2014,46(8):1503-1507
Alpacas are important to the economy of several countries. Little is known of Toxoplasma gondii infection in alpacas worldwide. In the present study, T. gondii was isolated and genetically characterized from alpacas for the first time. Alpacas (n?=?16) and rams (n?=?12) pastured on a farm in Virginia, USA, were examined at necropsy. Antibodies to T. gondii were determined by the modified agglutination test (MAT, 1:25) and found in 6 of 16 alpacas with titers of 1:100 (2 alpaca), 1:400 (2 alpacas), 1:800 (1 alpaca), and 1:1,600 (1 alpaca), and 5 of 12 rams in titers of 1:50 in one, 1:400 in one, 1:800 in one, 1:1,600 in one, and 1:3,200 in one. Tissues of all 16 alpacas were bioassayed in mice or in cats. Muscles (heart, skeletal muscle) of nine alpacas with MAT titers of 1:25 were fed to T. gondii-free cats; the cats did not shed oocysts. Viable T. gondii was isolated from tissues of two of six seropositive alpacas by bioassay in mice. Viable T. gondii was isolated from three of three seropositive sheep by bioassay in mice. Genotyping using cell-cultured tachyzoites revealed four genotypes, including one for ToxoDB PCR-RFLP genotype #2 (type III), one for genotype #3 (type II variant), one for genotype #170, and two for a new genotype designated as ToxoDB PCR-RFLP genotype #230. Thus, four of the five T. gondii isolates in the present study belonged to different genotypes. These results indicate a higher genetic diversity among T. gondii isolates circulating in the USA than previously realized. 相似文献
996.
Caroline Carvalho de Oliveira Severino Delmar Junqueira Villela Roberto Giolo de Almeida Fabiana Villa Alves Arthur Behling-Neto Paulo Gustavo Macedo de Almeida Martins 《Tropical animal health and production》2014,46(1):167-172
Our objective was to evaluate production, nutritive value and carrying capacity of piatã grass (Brachiaria brizantha cv. BRS Piatã), and performance of Nellore heifers in agrosilvopastoral systems (ASPS) with three eucalyptus (Eucalyptus urograndis) tree densities, during winter, spring, summer, and fall. Three integrated systems were evaluated: ASPS-1 (357 trees ha?1), ASPS-2 (227 trees ha?1), and CON (5 trees ha?1). In each system, two sward heights were evaluated: short and tall. A total of 80 11-month-old Nellore heifers were randomly allocated in a randomized split-plot block, 3?×?2 factorial. Greater dry matter availability was observed on CON pastures during the fall season. Greater percentage of leaf lamina was detected on ASPS-1 with short sward height and greater during summer, compared with other seasons. A greater forage production was observed between tree rows and for tall sward height. Spring was the season with less forage nutritive value. Average daily gain was greater during summer and fall. Gain per hectare and stocking rate were greater on CON system and on ASPS-2. Pastures with short sward height had greater gain per hectare and stocking rate. Agrosilvopastoral systems with intermediate tree density seem to be a good choice for producers willing to diversify their revenue sources without decreasing animal production. 相似文献
997.
Olinta Leone Cota Darcilene Maria de Figueiredo Renata Helena Branco Elaine Magnani Cleisy Ferreira do Nascimento Luiza Freitas de Oliveira Maria Eugênia Zerlotti Mercadante 《Tropical animal health and production》2014,46(7):1229-1234
The objective was to evaluate the emission of enteric methane by Nellore cattle subjected to different nutritional plans, as well as the intake and digestibility of nutrients from the diets supplied. Forty-seven animals in a confinement system (feedlot) were fed a corn silage-based diet for 35 days. Afterwards, these animals were evaluated in a grazing system during the rainy periods, in Urochloa brizantha cv Marandu paddocks, for 44 days. Chromic oxide was used as external marker to estimate the fecal production of animals. Samples of feces, ingredients, and pasture were collected and sampled for subsequent chemical analyses. The SF6 tracer gas technique was adopted to quantify the methane gas emitted by the animals. The experimental design was completely randomized, using procedure GLM of software SAS (9.2), including the fixed effects of sex and nutritional plan and the linear effect of the co-variable weights. Means were analyzed by Tukey’s test at 5 % probability. The intakes of total dry matter and organic matter were greater for the animals subjected to the feedlot diet (P?0.05). In this treatment, the animals showed greater dry matter digestibility, whereas the organic matter digestibility was lower (P?0.05). The digestibility of the dry matter was higher in confinement, whereas the digestibility of the organic matter was lower in this treatment (P?0.05). Emission of CH4/day (104.01 g) by the animals fed the feedlot diet (P?0.05) was greater, but the loss of consumed energy for methane production (CH4/CEB) and methane emission per dry matter consumed were lower in relation to the grazing treatment (3.75 vs 4.23 % and 11.67 vs 15.71 g/kg). The better quality of the diet in the feedlot promoted lower energy losses as methane. 相似文献
998.
Thaisa Campos Marques Karen Martins Leão Marco Antônio de Oliveira Viu Roberto Sartori 《Tropical animal health and production》2014,46(2):405-410
The objective of this study was to examine the effects of increasing circulating progesterone in multiparous Holstein cows, using an intravaginal progesterone implant between days 3 and 7 following fixed-time artificial insemination (FTAI). The animals were randomly assigned into two groups: (1) treatment group and (2) control (no treatment). The experiment took place during periods of high and mild temperatures. Pregnancy rates were evaluated by ultrasound at 30 and 60 days after FTAI; embryonic and fetal mortality rates were also evaluated on these dates. The temperature and humidity index on the day of FTAI were different (P?<?0.05) during the times of interest, but it did not affect conception rates. Neither the conception rates at days 30 and 60 nor the embryonic and fetal mortality rates differed between the groups during either the high- or mild-temperature periods (P?>?0.05). Throughout the experimental period, the serum progesterone concentration was higher in the treatment group than in the control (P?<?0.05). We conclude that the intravaginal progesterone implant inserted from days 3 to 7 following FTAI had no effect on conception rates at days 30 and 60 or on embryonic or fetal mortality rates but enhances the serum progesterone concentrations following treatment in multiparous Holstein cows during high- and mild-temperature periods. 相似文献
999.
Felipe Lamberti Pivoto Arlindo Gomes de Macêdo Junior Murilo Vieira da Silva Flávia Batista Ferreira Deise Aparecida Oliveira Silva Endrigo Pompermayer Luis Antônio Sangioni Tiago Wilson Patriarca Mineo Fernanda Silveira Flores Vogel 《Veterinary parasitology》2014,199(1-2):107-111
Protozoa from the family Sarcocystidae are agents of reproductive and neurological disorders in horses. The transmission of these protozoa may occur via horizontal or vertical means, and the frequency and potential of the later is not fully elucidated in horses. Thus, the aim of study was to correlation levels of antibodies in mares with pre colostral foals seropositive and assess the level and distribuition of antibodies against Neospora spp., Sarcocystis neurona and Toxoplasma gondii, in mares and pre colostral foals at the parturition. The blood samples were collected from mares immediately after parturition and from newborns before the ingestion of colostrum, and sera were analyzed for the presence of IgG by ELISA. It was found that 21.5%, 33.7% and 27.6% of mares were seropositive for Neospora spp., S. neurona and T. gondii, respectively; foals had antibodies at a rate of 8.3%, 6.6% and 6.6% for Neospora spp., S. neurona and T. gondii, respectively. Additionally, paired samples from mares and pre-colostral foals revealed an overall negative correlation between the serum reactivity against these three parasites and suggested that seronegative mares, or those with low to intermediate antibody levels, have a higher risk of giving birth to seropositive foals. 相似文献
1000.
Joao Victor Martins Antunes ;Robson Bonomo ;Maria da Penha Piccolo Ramos ;Marcelo Antonio Oliveira 《农业科学与技术》2014,(10):797-805
The aim of this study was to evaluate the physical, chemical and microbiological quality of the water of the Aroeira River in the city of Silo Mateus, northern region of Espirito Santo State, Brazil, from April 2012 to March 2013, for use in irrigation of vegetable crops. Five points were selected along the river for analysis of pH, chloride (mg/L C1-), total hardness (mg/L CaCO3), dissolved oxygen (mg/L O2), ammoniacal nitrogen (mg/L N-NH3), total iron (mg/L Fe), phosphate/orthophosphate (mg/L PO43-), turbidity (NTU), acidity (mg/L CO2), temperature (℃), electrical conductivity (dS/m), as well as microbiological and parasitological analyses. Only point l, located upstream of the points of domestic sewage discharges, is the closest to be considered suitable for use in irrigation of vegetable crop, demonstrating the possible risks to the health of populations who use water with sewage discharges in urban communities for irrigation of vegetable crops. 相似文献