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951.
Whether or not fruit buds in orchards can be protected from freezing by the use of fans, when no temperature inversion exists, depends upon the degree of bud radiant cooling at such times. Nighttime bud cooling in apple and peach orchards was estimated by comparing the temperature of buds and the adjacent air. The extent of radiant cooling was usually less than 0.6°C below ambient. Even this modest degree of radiant bud cooling appeared to require conditions with less than 60% cloud cover and wind speed less than 1 to 1.5 m s?1 at a height of 2 m. However, such conditions were also accompanied by inversions. The protective potential of fans in the absence of an inversion (postulated on the basis of bud radiant cooling) is therefore disclaimed on two accounts: (1) that the bud/air temperature difference is quite small and would only rarely span the bud critical temperature, and (2) that bud cooling would probably not occur during conditions which prevent the presence of an inversion. 相似文献
952.
953.
Evaluation of the Staph-Zym-system for identification of Staphylococcus hyicus and Staphylococcus intermedius 总被引:2,自引:0,他引:2
C L?mmler 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1989,36(3):180-184
The Staph-Zym system was evaluated as a means for identifying cultures of Staphylococcus hyicus isolated from pigs and bovines and cultures of Staphylococcus intermedius isolated from canines. The selected cultures had been identified by conventional methods. The Staph-Zym system correctly identified all 52 S. hyicus and all 33 S. intermedius. It is concluded that the Staph-Zym system is a practical and reliable test for identifying mostly animal pathogenic S. hyicus and S. intermedius, and might possibly be useful for veterinary microbiologists. 相似文献
954.
A. Basumatary J. J. Shangne K. N. Das D. Bhattacharyya 《Journal of plant nutrition》2018,41(11):1436-1443
A field experiment was conducted to assess the effect of sulfur (S) fertilization on distribution of S in soil and use efficiency on blackgram in subtropical Inceptisol of acidic soil of Assam, India. Five levels of S were applied (0, 10, 20, 30 and 40 kg S ha?1) along with recommended dose of nitrogen, phosphorus and potassium. Available S content gradually decreased with the advancement of crop growth stages and lowest value was observed at 60 DAS. Different S fractions were found to increase with increasing levels of S application and 40 kg S ha?1 resulted the highest content for all S fractions. The grain and stover yield of blackgram increased significantly up to 20 kg S ha?1 which was 95.69% higher over control. Agronomic efficiency, apparent S recovery and recovery efficiency of S were higher at 10 kg S ha?1and found decreased with increase in level of S. 相似文献
955.
The antioxidant activity of flavonoids from banana (Musa paradisiaca) was studied in rats fed normal as well as high fat diets. Concentrations of peroxidation products namely malondialdehyde, hydroperoxides and conjugated diens were significantly decreased whereas the activities of catalase and superoxide dismutase were enhanced significantly. Concentrations of glutathione were also elevated in the treated animals. 相似文献
956.
Magnetic Resonance Imaging of the Normal Canine Larynx 总被引:1,自引:0,他引:1
J. M. Vázquez A. Arencibia F. Gil J. A. Ramírez N. González C. D. Sosa J. R. Jaber 《Anatomia, histologia, embryologia》1998,27(4):263-270
The purpose of this study was to define the normal anatomic structures in the canine larynx with magnetic resonance images. TI-weighted images were taken in the sagittal and transverse planes. The MR images were obtained comparing MR images to dissection planes. Magnetic resonance imaging provides excellent anatomic detail of laryngeal structures. Therefore, it is of value for diagnostic imaging of some respiratory diseases in the dog. 相似文献
957.
Arnett EJ Fluharty FL Loerch SC Zerby HN Zinn RA Kuber PS 《Journal of animal science》2012,90(3):960-972
Jersey cattle are known for producing carcasses with a greater amount of marbling, but they require more days on feed to achieve acceptable market weights compared with other breeds. The objective of this study was to evaluate the effect of dietary forage (12 vs. 24% sudangrass:alfalfa hay, DM basis) in steam-flaked, corn-based finishing diets on carcass characteristics, beef palatability, and retail color stability of steaks from Jersey beef compared with conventionally fed commodity beef strip loins (COM) of identified quality (Choice(-) and Select(+)). Jersey steers (n = 77) were blocked by BW and randomly assigned to 1 of the following treatments for a 383-d trial period: Jersey low 12% (JL; n = 38) or Jersey high 24% (JH; n = 39) forage (DM basis). A comparison group was selected from conventionally fed cattle on the same day of slaughter as the Jersey treatments, and strip loins from USDA Select(+) (COM; n = 20) and Choice(-) (COM; n = 20) were removed for data analysis. Seventy-two hours postmortem, strip loins were removed, vacuum-packaged, and aged at 3°C for 18 d postmortem. After the aging period, steaks from the LM were sliced, vacuum-packaged, and frozen (-20°C) until analyzed. Jersey steaks had reduced (P < 0.05) Warner-Bratzler shear force values compared with COM steaks. Trained sensory panelists rated JL greater (P < 0.05) for initial and sustained tenderness and initial juiciness than COM, whereas JH was intermediate. As expected, marbling was greater (P < 0.05) for both JL and JH compared with COM, and trained sensory panel sustained juiciness, beef flavor intensity, and overall acceptability scores were greater (P < 0.05) for both JL and JH compared with COM; however, no differences (P = 0.14) were reported for consumer tenderness and flavor. Objective color (L*, a*, b*) measurements decreased (P < 0.05) over time across treatments. There were no differences among treatments for lightness (L*); however, overall during retail display JL were less (P < 0.05) red (a*) and yellow (b*) than JH and COM. Subjective color scores indicated both JL and JH were less red (P < 0.05) than COM. Steaks from Jersey were equal to and on some measurements more desirable than steaks from COM carcasses for both color stability and palatability. These results suggest that dietary forage level had minimal effects on carcass characteristics and beef palatability. However, feeding a low-forage diet decreases input cost and potentially results in a greater valued carcass. Finishing long-fed (383 d) Jersey steers can meet beef industry expectations with respect to quality grade. 相似文献
958.
959.
The process of colonization of Ascaris lumbricoides eggs by the fungus Verticillium chlamydosporium was studied by scanning electron microscopy. The preparations were made by fractionation of egg suspension exposed to the fungus for four days and frozen in liquid nitrogen according to St?rba and Milácek (1986). Ovicidal fungus forms an abundant ramifying mycelial network in the area between the eggs. However, egg-shells are penetrated only by some hyphae without any penetration organs produced (simple hyphal penetration). In a liquid medium, after penetration, hyphae inside the eggs rapidly grow among inner structures of egg-shells and on the surface of developing larvae. In the next phase, hyphae colonize the developing larva. The eggs attacked by this fungus remain morphologically unchanged for a long time except the sites of penetration. Verticillium chlamydosporium is a fungus with unique ovicidal properties. It colonizes the eggs of Ascaris lumbricoides at all stages of embryo development and also attacks larvae inside the eggs. 相似文献
960.
不同小麦品种茎秆抗倒性的研究 总被引:2,自引:0,他引:2
为了明确影响小麦抗倒伏性的主要因素,选用生产中应用较广泛的6个高产小麦品种,采用田间试验与实验室分析相结合的方法,对不同品种的抗倒伏性状进行研究。结果表明,百农矮抗58的倒伏指数较小,为0.432,与其他品种相比差异显著;百农矮抗58的茎秆机械强度大、茎秆基部第二节短粗、秆壁较厚、次生根数量较多、株高和重心高度较低。相关分析表明,倒伏指数与第二节关系密切,第二节机械强度越大、壁越厚、干重越大、地下部根量越多,倒伏指数就越小,茎秆抗倒性就越强;适当降低株高可以降低植株的重心高度,增强植株抗倒能力。逐步回归分析表明,影响茎秆抗倒性的直接因子为茎秆基部第二节机械强度、第二节干重、地下部根量及地上部鲜重,其中第二节机械强度对茎秆倒伏指数的直接作用最大,其直接通径系数为-0.775,可用第二节机械强度的大小评价品种茎秆抗倒性的强弱。 相似文献