微量元素锌在动物健康及营养中的研究进展

本文从锌对动物免疫、组织细胞结构完整性、生长繁殖能力等方面论述了锌的生理生化功能，并提出了如何在畜牧业生产中应用锌提高动物生产能力。对进一步研究锌在动物体的作用机理，将锌应用于畜牧业生产实际具有一定的参考价值。     

Therapeutic trial of granulocyte-colony stimulating factor for dilated cardiomyopathy in three dogs

Three dogs were presented to us for evaluation of cardiac problems. Electrocardiographic recordings revealed severe tachyarrhythmia and atrial fibrillation with ventricular tachycardia in 2 of the 3 dogs. The echocardiographic findings of the 3 dogs revealed markedly decreased fractional shortening and a marked increase in E-point septal separation. Based on the results of electrocardiographic and echocardiographic evaluation, the 3 dogs were diagnosed as dilated cardiomyopathy (DCM). The dogs were treated with conventional cardiac medication, but cardiac function did not improve and the clinical signs remained. We subsequently attempted treatment with granulocyte-colony stimulating factor (G-CSF; 10 microg/kg, subcutaneously). The specific purpose of G-CSF therapy for DCM was to improve cardiac function and a significant improvement in cardiac function was confirmed. The three dogs had no treatment side effects. This case report suggests that G-CSF might have therapeutic effects for medically refractory DCM in dogs.     

优质强筋小麦品质性状在不同土壤类型上的差异性研究

为了研究优质强筋小麦品质性状在不同土壤类型上的差异,以10个不同基因型优质强筋小麦品种(系)在5种不同土壤类型区的11个地点进行试验。结果表明,优质强筋小麦品质性状在不同土壤类型间的差异性较大,但不同性状的差异表现不一致。蛋白质含量表现为河潮土>棕壤>潮土>砂姜黑土>褐土,湿面筋含量和沉淀值表现为河潮土>棕壤>砂姜黑土>潮土>褐土,但变异系数相对较小,分别为5.80%、5.96%、12.06%;容重、硬度、面团形成时间、断裂时间、公差指数和评价值表现为砂姜黑土最优,褐土、棕壤次之,河潮土最差,容重、硬度变异系数较小为1.27%、6.38%,粉质参数变异较大,变异系数分别为10.08%、14.62%、16.90%、13.30%。     

农村居民点土地整理研究评述

[目的]分析国内农村居民点土地整理研究的重点和发展趋势。[方法]文献资料比较法。[结果]目前的农村居民点研究集中于农村居民点整理驱动力、整理潜力、整理模式、整理效益评价等方面。[结论]农村居民点整理潜力研究应与耕地整理等其他土地整理领域相结合,使农村居民点土地整理潜力计算方法更系统、更精确;要不断寻求农村居民点整理的模式创新,以促进农村居民点整理持续、健康发展,保障农村居民点整理目标的实现。     

尖头金线鲃人工繁殖初步研究

用人绒毛膜促性腺激素（HCG）、促黄体素释放激素类似物（LRH—A2）、马来酸地欧酮（DOM）组合对尖头金线鲃（Sinocyclocheilus oxycephalus）催产获得成功,用鲤脑垂体5mg／kg和人绒毛膜促性腺激素1000IU／kg组合催产失败。采取2次注射（第1次注射LRH—A2 2μg／kg,第2次注射LRH—A2 8μg/kg＋DOM3mg／kg＋HCG 1000IU／kg）催产效果明显;采取遮光孵化,孵化率明显提高。     

Usage of electrolytic water system in the giant freshwater prawn,Macrobrachium rosenbergii (de Man) larval hatchery system

The purpose of this study was to use an electrolytic oxidizing (EO) water system in a prawn hatchery. The results of the EO water generation efficiency showed that available chlorine in the EO water increased as the salinity and electric power increased, but was reduced as the water flow rate increased. A bactericidal activity assay showed that the growth of six aquatic pathogens was well inhibited by incubation with EO water containing 1 mg L^?1 of available chlorine. The removal of NH₃‐N and NO₂‐N by electrolysis at 15‰ and 5 W had significant effects, and the removal rate of NO₂‐N was much faster than that of NH₃‐N. Prawn zoea (Z) reared in EO water with different levels of available chlorine at 0 (control), 0.2, 0.3 and 0.4 mg L^?1 had mortalities of 0%, 12%, 27% and 42%, respectively, after 72 h. However, Z were able to well survive in activated carbon‐treated EO water for 1 week. For the on‐farm use of the EO water system in a prawn hatchery, larvae in the EO water group had faster development and higher survival than those in the activated carbon group. From these results, we believe that the EO water group had excellent water quality and lower bacterial counts resulting in increased larval development and survival.     

Comparative stomach contents and growth of the juvenile black seabream, Acanthopagrus schlegeli, reared in illuminated and unilluminated cages

The present study was designed to determine the positive effects of artificial illumination on the juvenile black seabream, Acanthopagrus schlegeli , by comparing stomach contents and growth between juveniles exposed to light and those maintained in the absence of light. The major prey items for juvenile black seabream reared in illuminated cages were amphipods (IRI%=50.5), copepods (IRI%=44.7) and polychaetes (IRI%=3.0), whereas those for the juveniles maintained in unilluminated cages were copepods (IRI%=96.0), amphipods (IRI%=3.4) and polychaetes (IRI%=0.6). The specific growth rates (SGR) of the juveniles reared in illuminated cages (0.99%) were significantly higher than those of the juveniles maintained in unilluminated cages (0.78%).     

Effects of Vibrio harveyi on plasma clotting protein (coagulogen) of white shrimp Litopenaeus vannamei

Blood clotting exhibits various important functions, including the prevention of body fluid loss and invasion of pathogens in shrimp. The effects of pathogenic Vibrio harveyi on plasma of white shrimp (Litopenaeus vannamei) in vitro and in vivo were investigated in this study. The clotting protein (coagulogen) in plasma of white shrimp pre‐incubated with extracellular products (ECP) of V. harveyi was found apparently decreased and fast‐migrated in crossed immunoelectrophoresis (CIE) gels. In addition, the coagulogen had been degraded to many low molecular‐weight protein bands in plasma pre‐incubated with ECP on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE) gels. When pre‐challenged with bacterial cells and ECP of V. harveyi, the white shrimp began to die at about 30 and 16 h respectively. Moreover, plasma coagulogen was decreased more obvious in shrimp challenged with ECP than that with bacterial cells as visualized in CIE gels, and total plasma protein in both group of shrimp were all decreased. Haemolymph withdrawn from moribund shrimp pre‐challenged with V. harveyi or its ECP was observed unclottable. However, the addition of clotting factors (transglutaminase and/or Ca²⁺) to these unclottable plasma could apparently promote their re‐clotting ability as jelly‐like solid observed in microtubes. The recovery of clotting ability of plasma from moribund shrimp was due to the reformation of coagulogen (200 kDa) after adding the two clotting factors as shown on CIE and SDS‐PAGE gels. The present results suggest that the infection of V. harveyi in white shrimp may not only degrade coagulogen but also influence the presence of transglutaminase and Ca²⁺ ion.     

成都平原不同耕作模式的农田效应研究—— II.土壤综合质量评价

 【目的】研究成都平原不同耕作模式对土壤质量性状的影响,探索建立适合当地生产条件的土壤质量评价体系,筛选出适宜该地的耕作模式,为提高当地土壤生产力水平、改善土壤质量提供借鉴。【方法】通过长期定位试验获取不同耕作模式对土壤性状及作物生产指标的影响效应,采用主成分分析的方法筛选评价指标,运用因子分析法对土壤质量进行综合评价。【结果】筛选出的评价土壤综合质量的指标在不同土壤层次存在明显差别：0—10 cm土层的主要影响因子为毛管孔隙度、土壤比重、土壤饱和渗水速率、土壤紧实度、土壤有机质;10—20 cm土层的主要影响因子为总孔隙度、非毛管孔隙度、饱和渗水速率、土壤吸湿水、土壤紧实度;0—20 cm土层的主要影响因子为非毛管孔隙度、土壤比重、土壤饱和渗水速率、土壤紧实度。其中,不同土层的共同影响因子——土壤饱和渗水速率和土壤紧实度是目前当地土壤质量的限制因子。土壤质量综合评价结果表明0—10 cm土层以麦稻双免耕作模式最好,10—20 cm土层麦免+稻旋最好,0—20 cm土层麦免+稻旋最好。【结论】在本研究的试验条件和当地实际情况下,对成都平原土壤质量具有良好效益的耕作模式为麦免+稻旋模式。     

豫棉15号在新疆棉区种植表现及高产性分析

豫棉15号是河南省农科院经作所从夏棉商855中的天然变异株中经过连续选择定向培育集丰产、优质、早熟、抗病于一体的棉花新品种.1996年该品种在新疆试种成功,1997年种植面积为1 259.9 hm2,1998年在南疆5地州种植面积猛增到22 666.7 hm2,并于当年12月上旬经新疆农作物品种审定委员会认定通过,准予在新疆棉区南疆亚区进行推广.