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81.
Debona Daniel Nascimento Kelly Juliane Telles Rezende Danielle Rios Jonas Alberto Bernardeli Arthur Martins Almeida Silva Leandro Castro Rodrigues Fabrício Ávila 《European journal of plant pathology / European Foundation for Plant Pathology》2015,142(3):603-614
European Journal of Plant Pathology - A set of standard area diagrams (SADs) was developed and validated to aid visual assessment of severity of frogeye leaf spot (FLS) caused by Cercospora sojina.... 相似文献
82.
Vanessa C. Luis Jaime Puértolas José Climent Juliane Peters Águeda M. González-Rodríguez Domingo Morales M. Soledad Jiménez 《European Journal of Forest Research》2009,128(3):221-229
We tested the hypothesis that fertilized containerized Pinus canariensis seedlings increases survival when planted in semiarid sites through the improvement of their physiological status during
the establishment phase by an increment in root growth. Seedlings were cultured under two different regimes: traditional (in
non-fertilized natural soil) and alternative (in fertilized peat). Morphological attributes and nitrogen content were measured
before planting. Measurements of survival and growth in the plantation were made periodically for 2 years and physiological
plant responses (leaf water potential, gas exchange and chlorophyll fluorescence) during the third summer after planting were
tested and finally a set of plants were excavated to measure the same parameters as before planting. Seedlings cultivated
using fertilized peat achieved the highest values for all of evaluated parameters. During the third dry season, big seedlings
exhibited better physiological status. Therefore, enhanced root growth can result in better water uptake during the dry period
thereby increasing survival and growth in the next few years after planting. A feed-back physiological model is proposed to
explain P. canariensis establishment in a semiarid environment. 相似文献
83.
R T Brandt G L Kuhl R E Campbell C L Kastner S L Stroda 《Journal of animal science》1992,70(2):343-348
One hundred forty British x Exotic crossbred, yearling steers (370 kg) were used in a 2 x 2 factorial experiment to evaluate main effects and the interaction of grain type (steam-flaked sorghum grain [SFSG] or steam-flaked corn [SFC]) and level of supplemental far (0 or 4% yellow grease [YG]) on feedlot performance, diet NE concentration, carcass traits, and chemical composition and sensory properties of longissimus muscle. Steer performance and estimated dietary NEm and NEg values were not different between SFSG and SFC. Supplemental YG improved (P less than or equal to .05) gain/feed and estimated NEm and NEg of both SFSG and SFC diets. Compared with steers fed SFSG, steers fed SFC had a more yellow (P less than .05) subcutaneous fat color. Supplemental YG had an additive effect (P less than .025) on yellow color of subcutaneous fat but improved (P less than .08) the lean color of longissimus muscle. Grain type or supplemental YG had no effect on sensory properties or mechanical shear of longissimus muscle. Longissimus muscle cholesterol content was elevated (P less than .05) by supplemental YG (.49 vs .52 mg/g of wet tissue for 0 vs 4% YG, respectively); however, the biological significance of this result is questionable. Similarly, effects of YG on increased (P less than .05) stearic acid concentration and a higher concentration (P less than .05) of linoleic acid measured in longissimus muscle of steers fed SFSG vs SFC were small in magnitude. These data indicate that under the conditions of this experiment, NE contents of SFSG and SFC were similar.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
84.
Lund C Kuhl S Mischke R Günzel-Apel AR 《Berliner und Münchener tier?rztliche Wochenschrift》2000,113(11-12):447-453
In the present study, blood samples were taken from clinically healthy puppies of the breeds Beagle, German Shepherd, and Golden Retriever between days 1 and 3 (n = 146), 8 and 10 (n = 137), 28 and 33 (n = 151), and 50 and 58 (n = 129) post natum. Measurements for red blood cell count, haemoglobin concentration, haematocrit, mean erythrocyte volume (MCV), mean corpuscular haemoglobin (MCH), and mean corpuscular haemoglobin concentration (MCHC) were performed by a semi-automatic blood cell counter; the normoblast number was counted visually. Between the 1st and 3rd day of life, the erythrocyte number of the puppies was 4.57 +/- 0.68 10(6)/microliter and, as such, was clearly below the reference range for adult animals. It further decreased by the 2nd measurement (8th to 10th day of life) to 3.59 +/- 0.41 10(6)/microliter, and then increased again to 4.75 +/- 0.68 10(6)/microliter (reference range: 3.73-6.25 10(6)/microliter, 2.5% to 97.5% percentile) by the final measurement (50th to 58th day of life). The measurement values of the haemoglobin concentration (13.5 +/- 2.0 g/dl) and haematocrit (41.0 +/- 6.5%) after birth were only insignificantly below or around the lower limit of the reference range for adult animals. Both parameters decreased to a more pronounced extent than did the erythrocyte count. They reached a minimum of 8.4 +/- 1.0 g/dl and 26.8 +/- 3.2%, respectively, between the 28th and 33rd day of life. Even at the end of the examination period (50th to 58th day of life), the values of these parameters (10.1 +/- 1.1 g/dl, reference range: 7.5-11.8 g/dl; 32.1 +/- 4.2%, reference range: 24.8 to 40.8%) were remarkably lower than the minimum of reference range for adult dogs. At the 1st sampling (between 1st and 3rd day of life), MCV (89.8 +/- 6.7 fl) and MCH (29.6 +/- 1.9 pg) were distinctly higher than the reference values for adult dogs. Both parameters decreased with increasing age. Thus, from the 50th-58th day of life, the results were comparable to those of adults. No considerable age dependence was found for MCHC. During the first days of life a relatively high number of normoblasts (8 +/- 7/100 Leukozyten) was found; it decreased rapidly. The study revealed significant differences between the breeds, e.g. German Shepherd dogs had lower initial values of erythrocyte count, haemoglobin concentration, and haematocrit when compared to the other breeds. Puppies of this breed also had higher normoblast numbers than the Beagle and Golden Retriever puppies at the 2nd and 3rd samplings. No clear sex differences in the studied parameters were observed. The results of this study reflect the replacement of fetal erythrocytes by postnatal erythrocytes. Moreover, they illustrate the need to use age as well as breed-specific reference ranges. 相似文献
85.
Tsousis G Herzog K Bitter J Krüger L Bollwein H 《Berliner und Münchener tier?rztliche Wochenschrift》2008,121(1-2):78-85
The aim of this study was to investigate if, compared with transrectal manual palpation, B-mode sonography provides additional information about the uterine structures and contents of Holstein-Friesian cows without and with disturbances during the early puerperal phase, that lead to a more precise diagnosis. The examinations were carried out once per cow either during the first four days p. p. (contraction phase, KPH) or on days 5 to 10 (desquamation phase, DPH) or on days 11 to 14 (regeneration phase, RPH) in 57 cows with undisturbed (UP) and 69 with disturbed puerperal phases (GP). The mean size of the uterus measured by transrectal palpation was 0.94 to 1.51 points (on a 6-point scale, p < 0.05) larger throughout the examination period and the fluctuation was 1.29 and 0.92 points (on a 4-point scale, p < 0.05) higher in GP cows compared with UP cows during the KPH and RPH, respectively. During the KPH, contractility of the uterus was 0.56 points (on a 3-point scale, p < 0.05) lower in GP cows compared with UP cows. Sonographically the cross sectional area of the most caudally located caruncle was 0.47 to 3.53 cm2 bigger (p < 0.05) in GP cows than in UP cows. The GP cows showed in the KPH a 0.21 cm thinner (p < 0.05) endometrium compared with the UP cows. In the DPH and RPH, the echogenicity was 1.63 and 1.04 points (on a 4-point scale, p < 0.05) higher and the intraluminal diameter of the uterine body was 0.49 to 0.67 cm greater (p < 0.05) in GP cows compared with UP cows, respectively. By means of dicriminant analysis 96.7% and 91.7% of the animals of the GP and UP group, respectively, where classified correctly during the DPH, whereas in the other two phases these proportions were between 70.0% and 87.5%. The results show that B-mode sonography is an additional valuable method for a more accurate differentiation of uterine involutionary processes between cows without and with disturbances of the puerperal phase. 相似文献
86.
Marcus Clauss Tamara A Franz-Odendaal Juliane Brasch Johanna C Castell Thomas Kaiser 《Journal of zoo and wildlife medicine》2007,38(3):433-445
Captive giraffe (Giraffa camelopardalis) mostly do not attain the longevity possible for this species and frequently have problems associated with low energy intake and fat storage mobilization. Abnormal tooth wear has been among the causes suggested as an underlying problem. This study utilizes a tooth wear scoring method ("mesowear") primarily used in paleobiology. This scoring method was applied to museum specimens of free-ranging (n=20) and captive (n=41) giraffes. The scoring system allows for the differentiation between attrition--(typical for browsers, as browse contains little abrasive silica) and abrasion--(typical for grazers, as grass contains abrasive silica) dominated tooth wear. The dental wear pattern of the free-ranging population is dominated by attrition, resembles that previously published for free-ranging giraffe, and clusters within browsing herbivores in comparative analysis. In contrast, the wear pattern of the captive population is dominated by abrasion and clusters among grazing herbivores in comparative analyses. A potential explanation for this difference in tooth wear is likely related to the content of abrasive elements in zoo diets. Silica content (measured as acid insoluble ash) is low in browse and alfalfa. However, grass hay and the majority of pelleted compound feeds contain higher amounts of silica. It can be speculated that the abnormal wear pattern in captivity compromises tooth function in captive giraffe, with deleterious long-term consequences. 相似文献
87.
88.
Charged particles traveling through matter at speeds larger than the phase velocity of light in the medium emit Cherenkov radiation. Calculations reveal that a given angle of the radiation conical wavefront is associated with two velocities, one above and one below a certain speed threshold. Emission at subluminal but not superluminal speeds is predicted and verified experimentally for relativistic dipoles generated with an optical method based on subpicosecond pulses moving in a nonlinear medium. The dipolar Cherenkov field, in the range of infrared-active phonons, is identical to that of phonon polaritons produced by impulsive laser excitation. 相似文献
89.
During speech acquisition, children form quick and rough hypotheses about the meaning of a new word after only a single exposure-a process dubbed "fast mapping." Here we provide evidence that a border collie, Rico, is able to fast map. Rico knew the labels of over 200 different items. He inferred the names of novel items by exclusion learning and correctly retrieved those items right away as well as 4 weeks after the initial exposure. Fast mapping thus appears to be mediated by general learning and memory mechanisms also found in other animals and not by a language acquisition device that is special to humans. 相似文献
90.
Juliane Lilienfein Wolfgang Wilcke Lourival Vilela Samuel do Carmo Lima Richard Thomas Wolfgang Zech 《植物养料与土壤学杂志》2000,163(4):411-419
No‐tillage (NT) cropping systems are becoming increasingly important in the Brazilian savanna. To evaluate their sustainability we compared soil chemical properties in 1‐ to 3‐year‐old NT systems following 9 to 11 years of conventional tillage (CT) with systems where CT was continuously in place for 12 years. In the rainy season 1997/98, NT was cropped with soybean and CT with corn while in the rainy season 1998/99 both systems were cropped with soybean. Soil solid phase samples were taken from the 0—0.15, 0.15—0.3, 0.3—0.8, 0.8—1.2, and 1.2—2 m layers on three spatially separated plots under each of NT and CT. Soil solution samples were collected weekly at 0.15, 0.3, 0.8, 1.2, and 2 m soil depth during two rainy seasons (14 October to 28 April 1997/98 and 1998/99). We determined soil moisture contents, pH, the concentrations of exchangeable cations, the electrical conductivity (EC) of the soil solution, and the concentrations of Al, C, Ca, Cl—, K, Mg, Mn, Na, NH4+, NO3—, P, S, and Zn in solid soil and soil solution samples. Differences in soil solid phase properties and moisture content between NT and CT were small, few were significant. Under NT, the average solution pH was significantly lower (5.5), Al (26 μg l—1), Mn (17 μg l—1) and total organic C concentrations (TOC, 6.5 mg l—1) were higher than under CT (pH: 6.0, Al: 14μg l −1, Mn: 14μg l −1, TOC: 5.5 mg l −1). Irrespective of the different crops in the first rainy season, under NT, the EC (205 μS cm—1), Ca (17 mg l—1), and Mg (2.9 mg l—1) concentrations at 0—0.3 m depth were lower than under CT (EC: 224 μS cm—1, Ca: 25 mg l—1, Mg: 5.6 mg l—1). At 1.2—2 m depth, the reverse order was observed (EC: 124 μS cm—1 under NT and 84 μS cm—1 under CT, Ca: 11 mg l—1 under NT and 7.5 mg l—1 under CT, Mg: 3.1 mg l—1 under NT and 1.8 mg l—1 under CT). Our results indicate that enhanced soil acidification because of higher rates of organic matter mineralization and a more pronounced nutrient leaching because of increased pore continuity may limit the sustainability of NT. 相似文献