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171.
Karine Campagnolo Felipe Ledur Ongaratto Camila Rodrigues de Freitas Camilo Andrés Peña Bello Bruna Rodrigues Willhelm Karine de Mattos José Luiz Rigo Rodrigues Marcelo Bertolini 《Reproduction in domestic animals》2020,55(5):574-583
Important genomic imprinting changes usually occur following the in vitro production (IVP) of bovine embryos, especially in the imprinting pattern of components of the IGF system. This study aimed to evaluate the effects of a transient episomal overexpression of the IGF2 gene in bovine IVP embryos following embryo cytoplasmic microinjection (CMI) at the 1-cell stage on embryo survival, early and late developmental kinetics and morphological quality up to Day 7 of development. Selected cumulus–oocyte complexes (COCs) were matured and fertilized in vitro and subsequently segregated into six experimental groups: non-CMI control group and five CMI groups at increasing doses (0, 10, 20, 40 and 80 ng/μl) of a GFP vector built for the episomal expression of bovine IGF2. Zygote CMI was effective in delivering the expression vector into the ooplasm, irrespective of the groups, with 58% of positive GFP fluorescence in Day 7 blastocysts. Considering developmental rates and late embryo kinetics, the 10-ng/μl CMI vector dose promoted a lower blastocyst rate (10.4%), but for blastocysts at more advanced stages of development (93.0% blastocysts and expanded blastocysts), and higher number of cells (116.0 ± 3.0) than non-CMI controls (23.3%, 75.0% and 75.0 ± 6.8 were obtained, respectively). In conclusion, CMI at the 1-cell stage did not compromise subsequent in vitro development of surviving embryos, with the 10-ng/μl group demonstrating a possible growth-promoting effect of the IGF2 gene on embryo development, from the 1-cell to the blastocyst stage. 相似文献
172.
Ali Ismael Choukeir Levente Kovács Luca Fruzsina Kézér Dávid Buják Zoltán Szelényi Mohamed Kamel Abdelmegeid András Gáspárdy Ottó Szenci 《Reproduction in domestic animals》2020,55(11):1535-1540
In this study, the utility of a commercial intravaginal thermometer was evaluated as an automated method for the prediction of calving in a total of 257 healthy pregnant Holstein–Friesian female cattle. The accuracy and the sensitivity of predicting calving within 48 hr before calving were also evaluated. The intravaginal temperature changes from 72 hr before and up to calving were significantly (p ≤ .001) affected by parity, season (summer vs. autumn), the time of day (8 a.m. or 8 p.m.) and the 6-hr time intervals (38.19°C: first interval 0 to 6 hr before calving vs. 38.78°C: twelfth interval 66 to 72 hr before calving), while the gender (p = .943), and the weight of the calf (p = .610), twinning (p = .300), gestation length (p = .186), foetal presentation (p = .123), dystocia (p = .197) and retention of foetal membranes (p = .253) did not affect it significantly. The sensitivity of the SMS of expecting calving within 48 hr and the positive predictive value were 62.4% and 75%, respectively, while the sensitivity and the positive predictive value for the SMS of expulsion reached 100%. It can be concluded that the investigated thermometer is not able to predict calving within 48 hr accurately; however, imminent calving can be accurately alerted. 相似文献
173.
de Oliveira Wildiney Freire de Lima Elizanne Moura de Freitas Denise Ribeiro dos Santos Suely Sousa Reis Grazielle Carvalho Gomes Daiany Iris Alves Kaliandra Souza Maciel Raylon Pereira Vargas Julián Andrés Castillo Mezzomo Rafael 《Tropical animal health and production》2020,52(5):2379-2385
Tropical Animal Health and Production - We aimed to evaluate the chemical composition, production yield, and economic viability of Minas Frescal cheese produced with milk from buffaloes... 相似文献
174.
Fábio Luiz Partelli Marcos Góes Oliveira André Monzoli Covre Henrique Duarte Vieira Jairo Rafael Machado Dias Heder Braun 《Journal of plant nutrition》2013,36(19):2536-2546
The objective of this study was to establish a nutrient sufficiency range and DRIS standards of Conilon coffee grown in southern Bahia, Brazil for the pre-flowering and grain-filling stages and to perform a nutritional diagnosis of these plants using different methods. The collections were performed in 24 Conilon coffee farm fields to establish the leaf nutritional standards, and 278 samples were collected to the nutritional diagnosis. The nutritional diagnosis was performed by using the sufficiency range criterion and the DRIS method. The nutrient sufficiency range and the DRIS standards must be specific to each phenological stage of the Conilon coffee plants. The leaf concentrations of calcium (Ca), sulfur (S), and boron (B) were higher in the pre-flowering stage; and the leaf concentrations of nitrogen (N), potassium (K), copper (Cu), and zinc (Zn) were higher in the grain-filling stage. 相似文献
175.
In order to obtain a better understanding of the behaviour, at the cuticular level of Zn deposited on leaves in natural conditions, the cuticular retention and penetration of this element were studied in vitro, using enzymatically isolated cuticles from pear leaves (Pirns communis L. cv. Passe Crassane). The cuticular retention of Zn, supplied as 0,1 mM 65Zn Cl2 was related to plant species, increasing in the following order: Prunus armeriaca < Pirus malus cv. Golden < Pirus communis L. cv. William with a ratio Zn in cuticles (nmol/g)/Zn in the solution (nmol/g) varying from 282 to 613; it depended on the date of sampling of leaves, the results were apparently not connected with their age. Zn retained by the cuticular discs was lost partially by washing with water, and almost entirely with exchange solutions. The exchangeable fraction could not be precisely determined because of the progressive removal of 65Zn from cuticles, with water. This lability was between that observed with 54fin and 64Cu . Interactions with Cu and Ca were considered, the cuticular retention of 0.1 mM Zn was drastically reduced from 0.01 mM only with Cu suggesting a high cuticular selectivity of Cu over Zn. The cuticular retention of Zn was higher with dewaxed cuticles probably because of a better access of Zn to fixation sites on the cuticular matrix.
The cuticular penetration of Zn was very slow through carefully selected cuticles but was faster with diluted HCl or non radioactive ZnCl2 rather than with pure water in the receiver unit. The validity of results obtained with isolated cuticles is discussed. 相似文献
176.
177.
Raúl López-Aguilar Andrés Orduño-Cruz Armando Lucero-Arce Bernardo Murillo-Amador Enrique Troyo-Diéguez 《Soil Science and Plant Nutrition》2013,59(3):329-336
Abstract The material balance of all the chemical species associated with the phosphate sorption reaction by two amorphous clays, silica-alumina gel and synthetic goethite was investigated adjusting the initial pH to 4.0, 5.0, 6.0, and 7.0. Phosphate sorption was found to decrease with increasing initial pH. During phosphate sorption, the equilibrium pH rose, adsorption of Cl- decreased to a state of negative adsorption, adsorption of Na+ increased markedly, silicate was released, and Al in the solution was precipitated. With increasing initial pH, the amount of apparent released OH- increased, the amount of Na+ adsorption increased, and the amount of released silicate decreased. The overall relationship of the material balance is explained in terms of the charge balance associated with phosphate sorption. 相似文献
178.
Lira Vanessa de Araujo Jumbo Luis Oswaldo Viteri de Freitas Giselle Santos Rêgo Adriano Soares Galvão Andréia Serra Teodoro Adenir Vieira 《Phytoparasitica》2021,49(1):103-111
Phytoparasitica - The red palm mite, Raoiella indica Hirst (Acari: Tenuipalpidae), is a severe pest of coconut (Cocos nucifera L.), banana (Musa sp.), and some ornamental palms. The predatory mite... 相似文献
179.
Hernández-Pérez T Carrillo-López A Guevara-Lara F Cruz-Hernández A Paredes-López O 《Plant foods for human nutrition (Dordrecht, Netherlands)》2005,60(4):195-200
Biochemical and nutritional changes were studied during the ripening process of three Opuntia morphospecies with different ripening behavior: Naranjona (O. ficus-indica), Blanca Cristalina (Opuntia sp.), and Esmeralda (Opuntia sp.) of early, early-intermediate, and intermediate-late ripening, respectively. In loss of fresh weight, Naranjona showed
the highest values, while in Blanca Cristalina and Esmeralda, a discrete weight loss was found. No significant differences
were found among morphospecies in soluble solids, total titratable acidity and pH during the postharvest days. Blanca Cristalina
and Esmeralda showed an increase in the content of carotenoids, while these diminished in Naranjona. The cell wall enzymes
evaluated showed particular behaviors during the ripening of each morphospecies suggesting a fine biochemical control and
not a clear relationship between fruit softening and enzyme activity. This study provides basic information on prickly pear
ripening, in order to understand this process for its control and for improving shelf life. 相似文献
180.
Simone Albino Paes André Wilson Campos Rosado Ailton Reis Olinto Liparini Pereira 《Plant pathology》2022,71(2):386-399
In Brazil, sour rot is an important postharvest disease on fruits and vegetables. Geotrichum candidum (synonym Galactomyces candidus) has been reported as the main species causing this disease. However, the identity of the causal agent is still uncertain. This research aimed to determine the identity of 165 fungal isolates associated with sour rot obtained from fruits and vegetables in Brazil, and to evaluate the effect of different temperatures on the incidence of sour rot on artificially inoculated tomato fruits. Based on the phylogenetic analyses of DNA sequences from the D1/D2 domain of the large subunit (LSU) rRNA gene and morphological analyses, 129 samples belonged to Galactomyces candidus, 15 to G. candidum var. citri-aurantii, 6 to G. phurueaense, 2 to Gal. pseudocandidus, 1 to Hyphopichia burtonii, 1 to H. khmerensis, 3 to Saccharomycopsis crataegensis, 1 to S. vini, 1 to Magnusiomyces tetrasperma, 1 to Trichosporon coremiiforme, and 1 to Zygoascus meyerae. Two new species were found, namely, Geotrichum solani (on potato) and Geotrichum spondiadis (on red mombin). All isolates were pathogenic when inoculated on healthy tomato fruits, including the new species of Geotrichum, which were also inoculated into their respective hosts, that is, potatoes and red mombins. To the best of our knowledge, this study is the first to report the presence of five other genera besides Geotrichum associated with sour rot on fruits and vegetables in Brazil, which demonstrates the diversity of fungi and yeasts associated with this disease. 相似文献