Vulnerabilities and fisheries impacts: the uncertain future of manta and devil rays

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Chemical Attributes of Soil and Forage Yield of Pasture Recovered with Phosphate Fertilization and Soil Management

Extensive and semi-extensive pastures are the basis of Brazilian livestock production. However, much of it is degraded or in degradation process, with low stocking rate per area. Even with this problem, this management type is 60% and 50% of Australia’s and the United States’ production costs, respectively. In order to research alternatives for Urochloa decumbens degraded pasture recovery in an Oxisol, Stylosanthes (Stylosanthes spp.) “Campo Grande” cultivar was introduced and phosphate fertilization was applied. The experimental design was of randomized blocks, 7 × 2 × 2 factorial design, with four replicates, involving seven systems to introduction (U. decumbens control; partial desiccation with 1.5 L ha^?1 glyphosate, total desiccation with 3.0 L ha^?1 glyphosate; direct planting; scarification, harrowing, and plowing + harrowing), phosphate fertilizer presence or absence, and two evaluation periods. “Campo Grande” Stylosanthes legume introduction increased shoot dry weight (SDW) yield, except in direct planting. Phosphorus fertilization increased SDW yield only in the first period, and Stylosanthes introduction in the pasture has not changed soil chemical properties. Phosphorus (P) fertilization also provided available P and exchangeable calcium (Ca²⁺) content in the soil increase, in addition to sum of bases and cation exchange capacity increase.     

Impact of varietal resistance in rice and predation on the mortality of Sogatella furcifera (Horváth) (Homoptera: Delphacidae)

Highly resistant, resistant and susceptible rice cultivars were tested in the greenhouse to determine their effect on Sogatella furcifera (Horváth) populations. The highly resistant cultivar IR2035-117-3, with resistance genes Wbph 1 and Wbph 2, caused the highest S. furcifera mortality. When the effects of varietal resistance and predation were combined the increase in mortality due to predators was additive. The spider Lycosa pseudoannulata Boes. et Str., mirid bug Cytorhinus lividipennis Reuter, ladybird beetle Harmonia octomaculata (F.) and rove beetle Paederus fuscipes Curt. were effective predators of S. furcifera and generally caused 30% mortality on the various cultivars. Results indicate that the integration of varietal resistance and predation would provide effective control of S. furcifera populations under field conditions.     

Effects of zeranol on reproduction in beef bulls: scrotal circumference, serving ability, semen characteristics, and pathologic changes of the reproductive organs

Effects of zeranol on scrotal circumference, serving ability, semen characteristics, and postmortem measurements of the genital organs were determined in beef bulls from 9 to 20 months of age. Group 1 (n = 5) served as a nonimplanted control group. Group 2A (n = 5) was implanted with 36 mg of zeranol at birth and at 3 and 6 months of age. Group 2B (n = 5) was implanted with 36 mg of zeranol every 3 months from birth through 18 months of age. Scrotal circumference was adversely affected by zeranol in groups 2A and 2B, but values approached those of group 1 with increasing age. Serving ability was also affected adversely but tended to recover with increasing age. Semen quality was low in groups 2A and 2B and did not improve with increasing age. There was no difference in testicular weight, vesicular gland weight, and penis length among groups when bulls were slaughtered at 20 months of age. Epididymal weight was greater in group-2B bulls and was most likely a consequence of epididymal lesions. Histologic examination of the genital organs revealed that zeranol induced adenomyosis and sperm granulomas in the caudae epididymidis and markedly altered the structure of the sexual accessory glands of bulls in groups 2A and 2B. Alterations in the vesicular glands were characterized by reduced alveolar development and an increase in connective tissue. Low epithelium associated with focal areas of squamous metaplasia were common in the prostate of groups 2A and 2B bulls. Lesions in the bulbourethral glands were characterized by low glandular epithelium, focal areas of squamous metaplasia, cystic collecting ducts, and an increase in connective tissue. Groups 2A and 2B had more abnormal seminiferous tubules than did group 1. Lesions in groups 2A and 2B may have been direct effects of zeranol or may have resulted from reduced testosterone secretion.     

Die räumliche Variabilität von Schwermetall-Konzentrationen in Niederschlägen und Sickerwasser von Waldstandorten des Sollings

Local variability in the heavy metal concentrations of precipitation and seepage water from forest sites in the Solling Concentrations of Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb in precipitation and seepage water have been measured continuously with local replicates during a 6-months period at a beech and a spruce forest site. Variation coefficients of the avarage concentrations were, in most cases, well below 30 %, being mainly caused by local differences. Comparison of means showed a significant increase of heavy metal concentration in the canopy drip of beech (Mn, Fe, Pb) and spruce (Cr, Mn, Fe, Ni, Zn, Pb) compared to bulk precipitation measured in the open field. Concentration of Mn, Co, Ni, Zn and Cd in the seepage water is significantly higher under spruce compared to beech. These results point at higher filter efficiency of the spruce canopy, compared with beech, for air pollutants, but a smaller retention capacity of the soil under spruce for heavy metals.     

高效液相色谱仪期间核查方法研究

高效液相色谱仪做为强制检定仪器除按规定定期送法定检定机构进行检定外,在两次检定周期之间还需对使用频率高的仪器进行期间核查以维持设备校准状态的可信度.本文简述了期间核查的项目和方法,包括外观检查、输液系统检查、色谱柱和检测器性能检查及做好检查和处理结果的记录.     

中西医结合治疗羊传染性脓疱

2004年10月27日,我县王甫乡一养羊户的羊只发生以唇部皮肤呈菜花样增生、出血、溃烂为特征的疫病,畜主称之为"烂嘴病",该病传播快,发病率高,给养羊户造成严重的经济损失.笔者根据流行病学调查、临床症状诊断为羊传染性脓疱,采用中西医结合治疗,收到了较好的疗效.