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1.
Maria Antonia Machado Barbosa Kacilda Naomi Kuki Pedro Santos Peno Bengala Emilly dos Santos Pereira Angélica Fátima de Barros Sebastián Giraldo Montoya Leonardo Duarte Pimentel 《Journal of Agronomy and Crop Science》2020,206(2):263-276
Environmental conditions influence phenology and physiological processes of plants. It is common for maize and sorghum to be sown at two different periods: the first cropping (spring/summer) and the second cropping (autumn/winter). The phenological cycle of these crops varies greatly according to the planting season, and it is necessary to characterize the growth and development to facilitate the selection of the species best adapted to the environment. The aim of this study was to characterize phenological phases and physiological parameters in sorghum and maize plants as a function of environmental conditions from the first cropping and second cropping periods. Two parallel experiments were conducted with both crops. The phenological characterization was based on growth analyses (plant height, leaf area and photoassimilate partitioning) and gas exchange evaluations (net assimilation rate, stomatal conductance, transpiration and water-use efficiency). It was found that the vegetative stage (VS) for sorghum and maize plants was 7 and 21 days, respectively, longer when cultivated during the second cropping. In the first cropping, the plants were taller than in the second cropping, regardless of the crop. The stomatal conductance of sorghum plants fluctuated in the second cropping during the development period, while maize plants showed decreasing linear behaviour. Water-use efficiency in sorghum plants was higher during the second cropping compared with the first cropping. In maize plants, in the second cropping, the water-use efficiency showed a slight variation in relation to the first cropping. It was concluded that the environmental conditions as degree-days, temperature, photoperiod and pluvial precipitation influence the phenology and physiology of both crops during the first and the second cropping periods, specifically cycle duration, plant height, leaf area, net assimilation rate, stomatal conductance and water-use efficiency, indicating that both crops respond differentially to environmental changes during the growing season. 相似文献
2.
Gustavo Pereira Valani Aline Fachin Martíni Laura Fernanda Simes da Silva Renata Cristina Bovi Miguel Cooper 《Soil Use and Management》2021,37(1):22-36
Integrated crop–livestock–forest is a promising strategy to improve soil quality. It comprises four different integrated farming systems: crop–livestock, crop–forest, forest–livestock and crop–livestock–forest. This work systematically reviewed studies about integrated crop–livestock–forest systems and soil quality. A total of 92 papers were retrieved from the Web of Science—Clarivate Analytics platform, and the following information was analysed: publication year, institution, region of the studied site, type of integrated system, soil type, tillage system, maximum soil depth and the soil quality indicators assessed. Most studies were published in the second half of the 2010s. Brazil is a prominent focus of research about soil quality and integrated crop–livestock–forest systems, with significant contribution from its central and southern regions. The Embrapa was the main publishing institution, present in over one‐third of the studies. Crop–livestock was the most common integrated system, Ferralsols was the most common soil group, and most of the studied soils were clayey. No tillage was the main tillage system. Most studies focused on the topsoil, assessing physical and/or chemical soil quality indicators. More emphasis on biological indicators of soil quality is required, as well as assessments integrating biological, physical and chemical indicators of soil quality. Future works should compare different integrated systems, including assessments deeper in the soil profile, especially in systems with the forest component, and also in sandy and silty soils. Soil quality indicators that have been rarely used should be further tested. Novel indicators should be added to better understand the promotion of soil quality by integrated crop–livestock–forest systems. 相似文献
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J F Warner W H Fales R C Sutherland G W Teresa 《American journal of veterinary research》1975,36(7):1015-1019
The endotoxic activity of Fusobacterium necrophorum bov 5 was investigated. The supernatant (S) fluid and cell wall (CW) preparation, obtained after differential centrifugation of the ruptured cell mass, were lethal for mice. The toxicity of the S fluid was stable during prolonged storage, treatment with formalin, and heating for 15 minutes at 80, 100, and 121 C, but was destroyed by alkaline hydrolysis with 0.25 N NaOH. The toxic factor was found in a high molecular weight (MW) fraction after gel filtration. The properties exhibited by the toxic S fluid resembled those of endotoxic lipopolysaccharide (LPS). Extracted and partially purified LPS (endotoxin) from F necrophorum bov 5 demonstrated a mouse median lethal dose (mouse LD50) of 16.8 mg/kg of body weight. The toxic LPS material, a high molecular weight moiety as estimated by gel filtration, was resistant to ribonuclease (RNase), deoxyribonuclease (DNase), and pronase treatment. A positive Shwartzman reaction (median skin lesion dose (SLD50) equal to 3.32 mug/kg of body weight) and biphasic fever response (minimal dose required to produce a fever index of 40 sq cm which falls on the linear portion of dose-response curve (FL40) equal to 0.41 mug/kg of body weight) further indicated the toxin was endotoxin in nature. The LPS from F necrophorum bov 5 was less toxic than Salmonella typhimurium LPS; but had considerable toxicity for experimental animals. The toxic activity of the partially purified F necrophorum bov 5 endotoxin was separated into 2 fraction regions by diethylaminoethyl (DEAE)-cellulose chromatography. The data provide evidence for the production of a potent endotoxin, possibly composed of more than one toxic component, which may be released upon cell disruption. 相似文献
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Immunohistochemical differentiation of reactive from malignant mesothelium as a diagnostic aid in canine pericardial disease 下载免费PDF全文
E. Milne Y. Martinez Pereira C. Muir T. Scase D. J. Shaw G. McGregor L. Oldroyd E. Scurrell M. Martin C. Devine H. Hodgkiss‐Geere 《The Journal of small animal practice》2018,59(5):261-271
Objectives
To develop a provisional immunohistochemistry panel for distinguishing reactive pericardium, atypical mesothelial proliferation and mesothelioma in dogs.Materials and Methods
Archived pericardial biopsies were subject to haematoxylin and eosin staining, immunohistochemistry for cytokeratin, vimentin, insulin‐like growth factor II mRNA‐binding protein 3, glucose transporter 1 and desmin. Samples were scored for intensity and number of cells stained.Results
Ten biopsies of reactive mesothelium, 17 of atypical mesothelial proliferation, 26 of mesothelioma and five of normal pericardium were identified on the basis of haematoxylin and eosin staining. Cytokeratin and vimentin were expressed in all biopsies, confirming mesothelial origin. Normal pericardial samples had the lowest scores for insulin‐like growth factor II mRNA‐binding protein 3, glucose transporter 1 and desmin. Mesothelioma and atypical proliferative samples were similar to each other, with higher scores for insulin‐like growth factor II mRNA‐binding protein 3 and glucose transporter 1 than the reactive samples. Desmin staining was variable. Insulin‐like growth factor II mRNA‐binding protein 3 was the best to distinguish between disease groups.Clinical Significance
An immunohistochemistry panel of cytokeratin, vimentin, insulin‐like growth factor II mRNA‐binding protein 3 and glucose transporter 1 could provide superior information compared with haematoxylin and eosin staining alone in the diagnosis of cases of mesothelial proliferation in canine pericardium, but further validation is warranted. 相似文献8.
Paixão Sonália Ferreira Fritzen Juliana Torres Tomazi Crespo Sarah Elizabeth Izzo de Moraes Pereira Helder Alfieri Alice Fernandes Alfieri Amauri Alcindo 《Tropical animal health and production》2018,50(8):1947-1950
Tropical Animal Health and Production - Serological studies have characterized the presence of the bovine viral diarrhea virus (BVDV) infection in water buffalo herds worldwide. However, the... 相似文献
9.
María Teresa Tejedor-Junco Margarita González-Martín Estefanía Bermeo-Garrido Rebeca Villasana-Loaiza Elena Carretón-Gómez 《Veterinary research communications》2018,42(3):227-232
Doxycycline is an antibiotic that, in addition to the classic antibacterial use, is also prescribed to fight parasitic diseases, like heartworm disease in dogs. Despite the concern that the overuse of this antibiotic may decrease susceptibility of clinically important bacteria, the consequences of the prolonged doxycycline therapy in heartworm-infected dogs have never been studied before. We have analyzed the impact of this therapy on Staphylococcus aureus and Enterococcus antimicrobial resistance. In this study, 17 heartworm-infected dogs (10 that had completed the doxycycline treatment and 7 dogs that had not yet begun) were included. Twenty-four isolates of Staphylococcus aureus were obtained from two locations of each dog. After treatment, 73.3% of isolates were resistant to at least one antibiotic but only 22.2% of isolates before treatment. Most of doxycycline resistant isolates were obtained from dogs that have received treatment. Erythromycin resistance or intermediate susceptibility was detected in 45.6% of isolates, most of them from dogs after treatment. For Enterococci, 48 isolates were obtained from fecal samples (25 before treatment and 23 after treatment). Before treatment, 32% of isolates were resistant at least to one antibiotic while after, this data increase up to 65%. Comparing isolates before and after treatment, a clear increase in resistance to doxycycline (12% against 21.74%) and erythromycin (20% against 39.13%) was observed. Although the present work is a preliminary research, the results encourages the development of further studies to determinate the effect of prolonged doxycycline therapy on antimicrobial resistance. 相似文献
10.
Renata Pereira da Silva-Marques Joanis Tilemahos Zervoudakis Nelcino Francisco De Paula Luciana Keiko Hatamoto-Zervoudakis Pedro Ivo José Lopes da Rosa e Silva Núbia Bezerra do Nascimento Matos 《Tropical animal health and production》2018,50(3):495-501
Two experiments were conducted to evaluate reduced supplementation frequencies for grazing beef cattle in rainy season. In experiment 1, evaluating the nutritional parameters, four rumen-cannulated Nellore bulls (BW = 410 kg) were used. In experiment 2, evaluating animal performance, 48 Nellore bulls (BW = 358 kg) were used. The treatments were as follows: mineral supplement (MS) alone and MS plus protein-energy supplement provided 3×, 5× and 7×/week. Supplementation frequency did not affect (P > 0.05) intake and digestibility. Average daily gain was greater (P < 0.001) to supplementation compared with MS. The supplementation 5×/week resulted in greater weight gain per hectare (9.24) and higher economic returns during the study period (1.64%) compared to other supplementations. Supplementation 5×/week increased animal performance and positively influenced economic returns. 相似文献