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1.
Sonia Czarnes Pierre-Edouard Mercier Damien G. Lemoine Jihane Hamzaoui Laurent Legendre 《Journal of Agronomy and Crop Science》2020,206(5):505-516
Members of the bacterial genus Azospirillum are root-associated bacteria that increase yield in cereals by promoting growth and alleviating drought stress. How plants integrate the many bacterium-derived growth-promoting stimuli with other environmental factors to generate a coordinated response remains unresolved. Using a commercial Azospirillum strain, A. lipoferum CRT1 and two host maize cultivars, it was observed that bacterization reduced the drought-induced increase in lateral root growth and enhanced the flood-induced increase in lateral root growth in the more drought- and flood-sensitive cultivar. In the other one, A. lipoferum CRT1 only elicited a moderate root growth response under low soil water potential. The photosynthetic potential and activity were increased in the earlier cultivar and decreased in the later one, irrespective of the soil water content. No impact of the bacterium was seen on the growth of the leaves of both cultivars under both stresses until the third leaf stage, therefore suggesting that it is a consequence of multiple primary adaptations to biotic and abiotic stresses. It is suggested that host–bacteria recognition leads to a stress-specific modulation of the root response and a differential stress-independent effect on photosynthesis. This is the first report of the impact of Azospirillum under flood conditions. 相似文献
2.
J. Fraser McConnell BVM&S Laurent S. Garosi DVM 《Veterinary radiology & ultrasound》2004,45(4):327-330
Intervertebral disk extrusion is rarely reported in the cat. In this case, the clinical, radiologic, and magnetic resonance imaging findings of an acute intramedullary intervertebral disk extrusion in a 5-year-old domestic shorthaired cat are described. Radiographically, there was mineralized disk material within the vertebral canal. On magnetic resonance images, the disk material was found to be within the spinal cord. A linear disk trail extending from the disk space into the spinal cord may be specific for intramedullary disk extrusion. 相似文献
3.
Radiographic,computed tomographic,and arthroscopic diagnosis of radioulnar incongruence in dogs with medial coronoid disease 下载免费PDF全文
4.
Morlin Carneiro Franciele Angeli Furlani Carlos Eduardo Zerbato Cristiano Candida de Menezes Patricia da Silva Gírio Lucas Augusto Freire de Oliveira Mailson 《Precision Agriculture》2020,21(5):979-1007
Precision Agriculture - Crop monitoring through remote sensing techniques enable greater knowledge of average variability in crop growth. Canopy sensors help provide information on the variability... 相似文献
5.
Nicols Javier Litterio Augusto Matías Lorenzutti María del Pilar Zarazaga Martín Alejandro Himelfarb Manuel Ignacio San Andrs‐Larrea Juan Manuel Serrano‐Rodríguez 《Journal of veterinary pharmacology and therapeutics》2021,44(1):68-78
Cefquinome is a fourth‐generation cephalosporin that is used empirically in goats. Different physiologic factors like pregnancy or lactation could determine the pharmacokinetic behavior of drugs in the organism. The objectives of this study are to (a) compare the pharmacokinetics of cefquinome after intravenous and intramuscular administration in adult nonpregnant (n = 6), pregnant (n = 6), and lactating goats (n = 6), at a dose of 2 mg/kg, with rich sampling by nonlinear mixed‐effects modeling, (b) conduct a pharmacokinetic/pharmacodynamic analysis to evaluate the efficacy of the recommended posology in goats with different physiological states, and (c) determine the optimal posology that achieve a PTA value ≥ 90%, taking into account a T > MIC ≥ 60% of a MIC value ≤ 0.25 µg/ml, in the different subpopulations of goats for both routes. Gestation significantly increased Ka and V1, while reduced F0, Cl, and Q. On the other hand, lactation significantly increased V1 and reduced Tk0. Cefquinome concentrations achieved in placental cotyledon, amniotic fluid, and fetal serum indicate a minimal penetration across the placental barrier. Moreover, milk penetration of cefquinome was minimal. The total body clearance of cefquinome for goats was 0.29 L kg?1 hr?1, that is apparently higher than the reported for cows (0.13 L kg?1 hr?1) and pigs (0.16 L kg?1 hr?1). So, the optimal dose regimen for cefquinome after intravenous and intramuscular administration required higher dose and frequency of administration compared with recommendations for cows or pigs. Therefore, 2 mg kg?1 8 hr?1 and 5 mg kg?1 12 hr?1 could be used for IV and IM routes, respectively, for the treatment of respiratory infections caused by P. multocida and M. haemolytica, but only 5 mg kg?1 12 hr?1 by both routes should be recommended for Escherichia coli infections. 相似文献
6.
7.
Alana Batista dos Santos Mara Lúcia Albuquerque Pereira Herymá Giovane de Oliveira Silva Gleidson Giordano Pinto de Carvalho Taiala Cristina de Jesus Pereira Leandro Sampaio Oliveira Ribeiro José Augusto Gomes Azevêdo Maria das Graças Conceição Parada Costa Silva Larisse Borges Sousa Leandro Borges Sousa Daiane de Oliveira Alencar 《Tropical animal health and production》2016,48(3):509-515
8.
Ménard L Thompson A 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(5):487-491
The purpose of this prospective cohort study was to identify factors that place a dairy cow with uncomplicated milk fever (MF) at significant risk of becoming an alert downer cow (ADC) and to verify if these factors could be used to predict treatment outcome. Recumbent MF cows were examined before treatment and 52 were excluded due to complications. In all, histories and pretreatment serum samples were taken and the serum of 86 cows was analyzed for electrolyte levels (calcium, phosphorus, magnesium, and potassium). In total, 36 of the 86 samples were from ADCs and 50 from animals that responded to MF treatment (MFT). A binary-two-factor logistic model determined that a MF cow with a phosphorus pretreatment level of > or = 0.9 mmol/L was 12 times more likely not to become an ADC than one with a phosphorus level < 0.9 mmol/L (CI: 6.3,23.1). Also, a binary multivariable logistic regression analysis showed that a MF cow with a pretreatment calcium level > or = 1.7 mmol/L was 14 times more likely to become an ADC than one with a serum level < 1.7 mmol/L (CI: 2.0,98). Age and the other serum electrolytes were not statistically significant risk factors at the 0.05 level. The rigorous pretreatment examination and stringent adherence to protocol reduced ADC misclassification and fostered the strong association between single factor serum phosphorus levels and ADCs. By using a cutoff level of serum phosphorus at > or = 0.9 mmol/L, a practitioner could correctly predict that 95% of the MFs would not become ADCs and, therefore, this level would be a useful pretreatment predictor. 相似文献
9.
Maria Clia Ramos Bellenzani PhD Associate Professor Júlia Maria D'andrea Greve PhD Professor-Physiatrics Csar Augusto Martins Pereira 《Journal of Equine Veterinary Science》2007,27(11):475-480
Horseshoeing is a common practice, but effects on the hoof wall are poorly understood. Strain gauges were used to document and compare hoof behavior in vitro during flat weight bearing and after artificial heel elevation. Ten front limbs of Thoroughbred race horses, shod with conventional flat shoes, were used. Eight strain gauges were symmetrically distributed around the toe, quarters, and heels. Each limb was mounted to a testing machine (Kratos K5002; Kratos Dynamômetros, Ltda., Cotia-SP-Brazil) and subjected to a load equivalent to 30% of the donor's body weight. Strains (μ) were acquired by means of a computerized system and the results compared using Friedman and Wilcoxon statistical tests. There was greater strain variation when the heels were elevated. Compression predominated during flat weight bearing, with a tendency to horizontal traction after heel elevation. The changes in strain caused by heel elevation were not always symmetrical. Elevation of the heels tensed the toe and the medial quarter horizontally, increased load at the posterior portion of the hoof capsule, and hindered its expansion. 相似文献
10.
Ramos Silva JC Marvulo MF Dias RA Ferreira F Amaku M Adania CH Ferreira Neto JS 《Preventive veterinary medicine》2007,78(3-4):286-295
From September 1995 to February 2001, blood samples were collected from 865 neotropical felids belonging to 8 different species. These animals were housed in 86 institutions located in 78 cities of 20 Brazilian states. Our goal was to identify the risk factors associated with sero-positivity to Toxoplasma gondii in captive neotropical felids from Brazil. All serum samples were tested by the modified agglutination test (MAT), using formalin-fixed whole tachyzoites and mercaptoethanol. For each animal an individual questionnaire was filled with questions about tattoo number, felid species, age, sex, origin, number of animals in the group, introduction of new animals in the group, time in the institution, eating meat previously frozen for a period <7 days in the last 6 months, eating meat of run-over or euthanized animals in the last 6 months, predation of rodents or birds in the last 6 months and presence of domestic cats near the enclosures in the last 6 months. The total sero-prevalence was 55% (95% CI: 52%, 57%). We estimated a prevalence of 46% (95% CI: 40%, 54%) for jaguarundi (Puma yagouaroundi); 58% (95% CI: 53%, 63%) for ocelot (Leopardus pardalis); 50% (95% CI: 45%, 56%) for oncilla (L. tigrinus); 54% (95% CI: 46%, 62%) for margay (L. wiedii); 12% (95% CI: 4%, 31%) for Pampas-cat (L. colocolo); 83% (95% CI: 65%, 93%) for Geoffroy's-cat (L. geoffroyi); 64% (95% CI: 50%, 68%) for jaguar (Panthera onca) and 48% (95% CI: 42%, 54%) for puma (Puma concolor). Multiple logistic regression was used to evaluate the association between the variables in the questionnaire and sero-positivity to T. gondii. We concluded that the independent risk factors for toxoplasmosis were: age >3 years (OR = 4.75 [2.75; 8.2]), eating meat previously frozen for a period <7 days (OR = 2.23 [1.24; 4.01]), and consumption of animals that were run-over or euthanized (OR = 1.64; [1.14; 2.37]). 相似文献