猪链球菌病对肌肉注射多剂量青霉素G药物动力学的影响

本文报道猪链球菌病对肌肉注射多剂量青霉素G钾（15000IU/kg,每隔12h肌注1次,连续给药5次）在猪体内血清浓度和药物动力学影响的研究。通过皮下接种9-10亿个菌落形成单位的猪链球菌,人工诱发猪链球菌病。发病猪给药前的直肠体温比正常时至少升高1.5℃,第一次给药后8h内感染猪的直肠温度仍显著升高（P＜0.05或0.01）,并可观察到其他临床症状。给药后的不同时间间隔从前腔静脉采血,用微生物法测定血清青霉素G的浓度。病猪第一次给药和第五次给药后的血药浓度--时间数据用MCPKP计算机程序处理,均符合一级吸收二室开放模型。病猪第一次及第五次给药的主要药物动力学参数（平均值±标准差）分别是：t#-(1/2α)0.66±0.15及0.59±0.17h;t#-(1/2β)1.87±0.55及2.18±0.97h;t#-(1/2ka)0.35±0.05及0.20±0.09h（P＜0.05）;t#-(max)0.71±0.10及0.48±0.11h（P＜0.05）;C#-(max)7.48±0.97及9.04±0.62IU/ml（P＜0.01）;AUC16.84±1.64及16.42±1.65I U·h/ml,Tcp(ther)11.72±3.33及12.41±3.62h;笔者对引起病猪第一次及第五次给药的某些药物动力学参数有显著差异的原因进行了探讨。     

沼液施用对潮土氧化亚氮排放通量的影响

通过对潮土养猪沼液施加试验,采用静态箱．气相色谱法于2010年7月（夏季）、2011年3月（冬末春初）观测了不施沼液、正常施沼液及大量施沼液等3种处理的土壤氧化亚氮（N20）排放通量,研究其排放特征与影响因素。研究结果表明：①沼液施用显著提高了氧化亚氮平均排放通量（P〈0．001）,不同沼液处理（不施沼液、正常施沼液、大量施沼液）排放通量范围分别为11-25～68147μg·m-2·h-1,20．13～244．35μg·m-2·h-1,40．09～618．43μg·m-2·h-1;②土壤氧化亚氮排放通量除受沼液施加水平影响外,还随着土壤温度的提高而增加：③土壤氧化亚氮排放通量与土壤水分呈极显著相关（P〈0．001）．与土壤硝态氮质量分数显著相关（P〈0．05）;④以相同施氮量计,沼液施加引起的氧化亚氮排放速率远高于尿素或者硫胺等氮肥。图3表1参22     

桂东地区早稻稻鸭共作有机栽培试验初报

为探索适合本地水稻生态安全、优质高效生产技术,在桂东地区进行早稻有机栽培、稻鸭共作有机栽培和传统栽培三种模式试验研究。结果表明,三种模式水稻平均产量分别是394.6kg/667m2、430.2kg/667m2、508.9kg/667m2,稻鸭共作有机模式比传统模式每667m2低18.3%,比有机模式高9.0%;平均净收益分别为797.5元/667m2、936.8元/667m2、664.3元/667m2,以稻鸭共作模式最高,比有机栽培和常规栽培增加20.1%和24.3%。此外,稻鸭共作模式在控制稻田杂草和病虫害、提高肥力和改善稻田生态环境优于其它两种模式。     

Comparison of Spore Inoculated and Vegetative Propagated Cultivation Methods of <Emphasis Type="Italic">Gracilaria chilensis</Emphasis> in an Integrated Seaweed and Fish Cage Culture

In Chile the integration of Gracilaria chilensis with salmon culture has shown high potential. Seaweed integrated aquaculture is of great interest as it allows waste recycling within fed cage aquaculture. The development of economically feasible suspended methods of seaweed cultivation is therefore of high importance. Hence, production and performance of two suspended Gracilaria cultivation methods, spore inoculated ropes and ropes with twined field collected seaweed, were studied in open water. The production from spore-seeded ropes was comparable to that of twined ropes for the first month of culture. Thereafter, the twined ropes had a significantly higher productivity. Fish farm wastes had no significant fertilizing effect upon Gracilaria growth rate. In addition, spore-originated thalli and field collected thalli were compared under laboratory conditions and in suspended culture using the same cultivation method. Spore-originated thalli had a 50% lower growth rate than the field collected thalli under laboratory conditions; however, no significant differences were detected in the field. Also, the occurrence of spore coalescence growth enhancement was not significant on the spore-seeded ropes. It was concluded that spore-originated cultivation techniques could be of interest for an integrated open seawater aquaculture system due to the high levels of Gracilaria polymorphism. This would result in greater adaptability to environmental variations, and a continuous supply of restocking material.     

回归低熵化还是走向现代化--关于世界农业前途的讨论

20世纪70年代以来,围绕着农业发展前途问题,在世界上,尤其是西方国家,进行着热烈的争论．鉴于对资源环境的担忧,有些环境保护主义者主张农业走回归、低熵化、低投入、自然农业的道路,他们反对农业现代化,反对农业的外部投入,尤其是化石能的投入;另一些人则不赞成这种极端的复古思潮,主张走向农业现代化、集约化、商品化、持续化．本文从理论与实践两个层面对此进行了初步分析讨论,并提出了中国实现农业现代化、走集约持续农业道路的设想。     

我国东中西片农作制特征与战略优先序

在以县域为单元的中国农作制区划的基础上,将全国划分为三大片：东部沿海片、中部平原片和西部高原生态脆弱片。分析讨论了这三大片的农作制特征与战略优先序,以为宏观决策参考。     

长江中游平原及江淮地区农业资源优势与综合农业基地建设

长江中游平原及江淮地区是我国八大综合农业区之一,农牧渔各业生产在全国有举足轻重的地位。文章在分析本区农业资源优势和存在问题的基础上,提出了长江中游平原应加强以防洪为重点的水利建设,努力实现平衡增产和优质高产,巩固提高全国性的粮、棉、肉、鱼商品生产基地;江淮地区应加强水土治理和山丘、水面、滩涂资源的开发,以粮棉油为重点,积极发展畜禽、水产、蚕桑和乡镇企业。     

黄土高原黄河三角洲旱地农业集水补灌的气候学条件与特点

研究分析了晋南自然降水的规律和特点,为旱地集雨提供了重要的理论依据。指出可以通过蓄集径流雨水来调节降水的时空分布,以丰补欠,以余补缺,充分利用天然降雨,提高旱地农作物产量,增加旱区农民收入。     

Bioassays and application of olive pomace compost on emmer: effects on yield and soil properties in organic farming

Abstract

Composting olive oil pomace could solve the problem of disposal, by recycling this organic waste for agricultural purposes. Furthermore, application of composted organic waste could be a way to sustain both soil fertility and production, especially in organic farming. Therefore, the aim of this research was to evaluate the phytotoxicity and the effects of application of olive pomace composts on emmer performance and soil properties. Two types of olive pomace composts, with a different initial C/N ratio, were stopped at the active phase and processed until maturation. The obtained four olive pomace composts were compared with a commercial fertilizer in a two-year field experiment. Before the field trial, a bioassay was performed to assess phytotoxicity both for the raw pomace and the not-stabilized composts. Growing and yielding data for emmer were determined during the two-year period and soil characteristics were measured at the start and at the end of the experiment.

The composts were not phytotoxic (germination index was higher than 90%) and their total organic carbon content was always higher than the minimum values established by the Italian fertilizers legislation. The emmer protein content was significantly higher in the matured compost treatment with low C/N, than in the other compost treatments. Its value was comparable with that of the commercial fertilizer, suggesting a good performance on crop yield quality. Although not significant, this compost showed an increase of 9.8% in grain yield compared with commercial fertilizer treatment. On the whole, it can be suggested that repeated compost application might preserve the soil organic carbon content and supply macronutrients to a crop.     

中草药提取物对育肥猪生长性能和肉质的影响

选择体重60kg左右的“长×大”二元杂交阉公猪180头,随机分配到复方1#、复方2#、复方3#3个试验组和1个对照组;每组设5个重复,每个重复9头。试验结果如下：①复方1#、复方2#、复方3#组较对照组平均日增重分别提高4．83％（P〈0．05）、3．41％（P〉0．05）和8．84％（P〈0．05）;饲料,增重降低5．14％（P〈0．05）、0（P〉0．05）和5．43％（P〈0．05）;总疾病发生率下降48.9％（P〈0．01）、53．5％（P〈0.01）和17．3％（P〈0．01）。②复方1#、复方2#、复方3#组与对照组相比,屠宰率差异均不显著,但胴体瘦肉率提高,板油重降低,背膘厚降低。③复方1#、复方2#、复方3#组能改善肉质特性。研究表明。试验的中草药提取物组方能提高生长肥育猪的生长速度和降低饲料/增重;有效提高猪的抗病能力;可提高猪的胴体瘦肉率,增大眼肌面积,降低背膘厚;有效改善育肥猪肉质。