日粮水平对中华鳖稚鳖生长的影响

于2001年12月购买当年繁殖的中华鳖(Trionyx sinensis)稚鳖(28．66-53．37g),在30℃水温下进行摄食-生长实验(实验时间为56d),设饥饿、1％、2％、4％和饱食5个日粮水平,研究了摄食水平对中华鳖稚鳖生长和转化效率的影响。方差分析表明：摄食水平对中华鳖稚鳖的特定生长率和转化效率均有显著影响。稚鳖的湿重、干重、蛋白质和能量的特定生长率均随摄食水平的增加呈二次曲线增加,摄食率(RL)-干物质特定生长率(SGRd)的关系模型可表示为：SGRa=-0．0832RL^2 1．0795RL-1．8779(n=25,r^2=0．906．F=105．46);当摄食率为6．97％、6．49％、6．08％和6．34％时,稚鳖湿重、干重、蛋白质和能量的特定生长率分别达到最大值。1％组的各项转化效率均显著低于2％和4％组,干重和能量转化效率显著低于饱食组;2％组的干重和能量转化效率显著高于4％和饱食组。     

膨化饲料动植物蛋白比对中华鳖稚鳖生长特性的影响

本实验设计了营养相近、不同动植物蛋白比的四种膨化饲料（饲料1,1.5∶1;饲料2,3∶1;饲料3,5∶1;饲料4,7∶1）,研究了动植物蛋白比对中华鳖稚鳖摄食、生长、饲料利用能力和营养组成的影响。饲料1组稚鳖的摄食率显著高于饲料2—4组。饲料1—4组稚鳖的特定生长率没有显著影响。饲料1组稚鳖的干物质和脂类消化率、饲料转化效率、蛋白贮积率和能量贮积率显著低于饲料2—4组。饲料1组稚鳖体脂肪含量显著低于饲料4组。稚鳖的上述指标在饲料2—4组间均无显著差异。结果表明,鳖膨化饲料动植物蛋白比对中华鳖稚鳖生长特性有明显的影响,适宜的动植物蛋白比为3∶1。     

日本沼虾继饥饿后补偿生长研究

在25.0±1℃条件下,对日本沼虾Macrobrachium nipponense (湿重, 0.52～0.64 g )进行了不同时间的饥饿处理后再供食的恢复生长实验.对照组C连续饱食投喂18 d;处理组S2、S4和S8分别饥饿2、4和8 d后再饱食投喂16、14和10 d.结果 饥饿结束时各处理组的湿重均显著低于对照组;实验结束时S2、S4组与对照组间的湿重差异不显著,而S8组的湿重仍显著低于对照组;恢复生长时各处理组的湿重摄食率、食物转化率和生长率开始显著高于对照组,但随着恢复时间延长又逐步达到对照组水平.随着饥饿时间延长,日本沼虾标准代谢率降低.在恢复投喂后又逐步回升到对照组水平.实验结果表明,日本沼虾继饥饿后再恢复喂食出现完全或部分补偿生长效应不仅是由于增加食欲,提高了摄食水平,同时也改善了食物转化率.因此,补偿生长是这两种生理因素共同作用的结果.     

中华绒螯蟹亲蟹的饥饿代谢研究

1998年 10～ 12月 ,对体重为 5 4 .5 9(± 2 .37) g的亲蟹在 2 0 (± 0 .5 )℃温度条件下进行饥饿实验 ,研究了饥饿对中华绒螯蟹亲蟹代谢的影响 .结果表明 ,经过 30d的饥饿处理 ,亲蟹的耗氧率降低为摄食状态的 5 0 .0 % ;CO2 排出率减小为摄食状态的 6 3.4 % ;NH3 N排泄率减小为 5 9.1% .耗氧率和CO2 排出率、NH3 N排泄率的变化差别较大 ,耗氧率的减小可分为 4个阶段 ,而CO2 排出率和NH3 N排泄率的减小仅可分 3个阶段 .与此同时 ,亲蟹的标准代谢水平同样受到饥饿的影响 ,饥饿 30d后 ,由 4 .4 5J·g-1·h-1减小为 2 .36J·g-1·h-1;在饥饿亲蟹的代谢中 ,脂肪消耗最多 ,其次是碳水化合物 .     

真(鱼岁)(Phoxinus phoxinus(L.))的能量收支各组分与摄食量、体重及温度的关系

在不同的摄食水平(饥饿—最大量)及温度(5—15℃)下,对1—5g的真(鱼岁)的摄食量、排粪量、排泄量、代谢量,生长量及生化组成作了测定。真(鱼岁)的最大摄食量随体重及温度增加而增加。食物能量平均有6.5％损失于粪便中,5.1％损失于排泄物中。摄食代谢随摄食量增加而增加。在同一温度下,特定生长率与摄食量的关系是一减速增长曲线。当摄食不受限制时,生长率随温度增加而增加;当摄食受限制时,生长率随温度增加而下降。鱼体的干物质含量及能量含量随摄食量增加而增加。     

山瑞鳖驯化养殖、保护及其开发利用的初步研究Ⅱ.山瑞鳖的生长、饲养管理及保护利用

(续上期 )4　山瑞鳖的稚幼鳖的生长4 1　刚孵出的山瑞稚鳖的大小　测量了不同窝次刚孵出 3 5只稚鳖 (在鳖类从卵内刚孵出的鳖通称稚鳖 ,至于稚鳖期与幼鳖的界限则无定论。本文对山瑞鳖按体重划分为 :5 0 ｇ以下为稚鳖期 ,5 0～ 40 0ｇ为幼鳖期 ,40 0～ 40 0 0 ｇ为商品鳖 ,40 0 0 ｇ以上视为成年鳖 ) ,平均体重 7 4(6 0～ 9 1 ) ｇ ,背甲长宽 3 7 6× 3 0 9(3 0× 2 3～ 47× 3 4)ｍｍ ,腹盘长 2 5 0 (2 4～ 2 7)ｍｍ。4 2　山瑞幼鳖的生长　前述刚孵出的 3 5只稚鳖经过7个月的加温 (2 5℃ )饲养结果 ,除中途死亡 1 1只外 ,剩下 2 4只幼鳖…     

人工饲养条件下水温对中华鳖消化时间和生长影响的实验观察

我们于 1 996年在浙江省天地公司 ,对不同水温条件下 ,食物通过中华鳖 (Ｔｒｉｎｙｘｓｉｎｅｎｓｉｓ)消化道时间、幼鳖的生长及饲料效率进行了实验观察。1　材料与方法以同批稚鳖 ( 50 -1 0 0 ｇ)和成鳖 ( 3 0 0 -3 50 ｇ)随机分成 5组 ,每组 3只鳖。在 2 2℃、2 5℃、2 8℃、3 1℃、3 4℃的不同水温下单只饲养。饥饿一天后投喂混有直径 0 1 -0 8ｍｍ的不同颜色的塑料颗粒的配合饲料。自投喂 3小时后开始 ,每小时收集粪便一次。从投喂后 1 0分钟开始计时 ,至粪便中出现有色塑料颗粒即为食物通过消化道的时间。选择体重相近 ( 1 1 0 -1 4…     

外源维生素C及冬眠对中华鳖稚鳖生长、维生素C合成和肝脏维生素C含量的影响

本文研究了饲料中维生素C(Vc)对中华鳖稚鳖冬眠前后Vc合成能力及肝脏中Vc含量的影响。将体重为29.41g±5.44g的稚鳖180只,按其饲料中Vc含量(0、500、2500mgVc/kg饲料)分为Vc0、Vc500和Vc2500共3组,每组6个平行,每平行10只鳖。实验开始前称重得各组初始平均体重。25℃±1℃下用实验饲料饲喂4周后,缓慢降温至7℃,人工诱导其进入冬眠,此时为冬眠期开始,每组取6只鳖,称重后快速处死,取其肝脏和肾脏。其余鳖全部称重。冬眠8周末取样,处理同上。用高效液相色谱(HPLC)法测定肝脏Vc含量和肝脏、肾脏古洛糖酸内酯氧化酶(GLO)活力。结果发现中华鳖自身能够合成Vc,且合成部位在肾脏。饲喂4周不同Vc水平的饲料后,各组间特定生长率差异不显著。冬眠8周后,各组体重均有所降低,组间冬眠期间特定生长率无显著性差异。冬眠开始时,稚鳖肝脏Vc蓄积量有随外源Vc浓度升高而递增的趋势,但差异未达到显著性水平;经历冬眠后各组稚鳖肝脏Vc含量降低,Vc500组下降不显著,而Vc0与Vc2500组显著下降;肾脏GLO活力在不同Vc梯度组间及冬眠前后均无显著差异。以上结果表明:中华鳖冬眠过程中要消耗较多的肝脏Vc,外源Vc和冬眠对肾脏Vc合成能力影响不显著。     

完全或部分的食物剥夺对中华鳖(Pelodiscus sinensis)幼体补偿生长反应的影响:生长率的时间变化模式与体组成的变化

为了探究中华鳖（Pelodiscus sinensis）幼体的补偿生长能力,我们对中华鳖幼鳖（平均湿重9．56g）进行如下6种处理：饥饿0（对照）、1、2、3、4周,或者食物限制4周,即只投喂体湿重百分之一的食物;然后对各组进行饱食处理直到10周的实验结束为止。结果发现在饱食期的第一周各饥饿处理组的特殊生长率均显著高于对照组（P〈0．05）,但是终体重均没有赶上对照组。当饥饿或食物限制结束时,脂肪含量随着饥饿期的延长而降低,灰分和水分则表现出相反的变化趋势：脂肪含量显著低于对照（P〈0．05）,而灰分和水分则显著高于对照（P〈0．05）。蛋白含量则没有显著变化（P〉0．05）。实验结束时,除了灰分外（P〈0．05）,其他个体组成指标均恢复到对照组的水平。以上结果表明中华鳖幼体在饥饿胁迫下首先利用脂肪作为主要能源以维持生存,以及在该研究条件下完全的食物剥夺可以诱发其部分补偿生长反应．而部分食物剥夺则不能诱发此反应。     

饲料中Vc水平对中华鳖幼鳖生长及其组织中含量的影响

以中华鳖幼鳖为研究对象 ,以高稳定性维生素C磷酸酯为Vc源 ,研究饲料添加Vc对中华鳖生长及其Vc在组织中含量的影响。试验分别投喂基础配方相同而分别添加Vc 0、5 0、10 0、2 0 0、4 0 0、80 0mg/kg的饲料 ,在水温 31±2℃条件下养殖于结构相同、面积分别为 10 .5m2 的 18口水泥池中 ,进行为期 10 5d的养殖试验。结果表明 :(1)饲料添加Vc可提高中华鳖幼鳖增重率 ,其中添加 2 0 0mg/kg组效果最佳 ,与未添加组间差异显著 (P <0 .0 5 ) ;饲料添加Vc能提高蛋白质转化效率 ,添加Vc2 0 0、4 0 0、80 0mg/kg组与不添加的对照组之间差异均显著 (P <0 .0 5 ) ;而且 ,饲料添加Vc能降低饵料系数 ,但未达到显著差异 (P >0 .0 5 ) ;未添加的对照组和低剂量组未见有Vc缺乏症产生。(2 )基于试验幼鳖增重率折线法分析 ,中华鳖幼鳖获得最佳生长时的饲料Vc最低需求量为 184mg/kg ;(3)肝脏中Vc含量随着饲料Vc添加水平上升而增加 ,相关系数达 0 .95 4 2 ,各添加组与未添加组间有显著差异 (P <0 .0 5 ) ;肝脏Vc含量的回归分析表明 ,获得维持肝脏组织Vc储存最佳的饲料Vc添加水平为 192mg/kg。 (4)饲料添加Vc可显著地降低鳖体水分含量 (P <0 .0 1) ,并略能增加体脂沉积 (P >0 .0 5 )。     

Simultaneous measurement of the trace elements Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum and their reference ranges by ICP-MS

The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three reconstituted reference serum samples by comparison with other methods and by the standard addition procedure. The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision, and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest in the environment, the relatively delicate sample handling, and the high cost of the equipment.     

Distribution of N,P, K,Ca, Mg,S, Zn,Fe, Mn and Cu in groundnut

Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.     

Crystal structure, detonation performance, and thermal stability of a new polynitro cage compound: 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptacyclo [5.5.1.13, 11. 15, 9] pentadecane

A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability.     

Reference values for the concentrations of As,Cd, Co,Cr, Cu,Fe, I,Hg, Mn,Mo, Ni,Pb, Se,and Zn in selected human tissues and body fluids

This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues and body fluids. A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America, Australia, and New Zealand. This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world. It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different countries reflected some interesting associations for elements, such as Mn and Zn. Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as Cu, Fe, and Zn were not available. In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions, which sadly lack data of any kind at present.     

Monovalent Cation Permeation through the Connexin40 Gap Junction Channel : Cs,Rb, K,Na, Li,TEA, TMA,TBA, and Effects of Anions Br,Cl, F,Acetate, Aspartate,Glutamate, and NO3

The unitary conductances and permeability sequences of the rat connexin40 (rCx40) gap junction channels to seven monovalent cations and anions were studied in rCx40-transfected neuroblastoma 2A (N2A) cell pairs using the dual whole cell recording technique. Chloride salt cation substitutions (115 mM principal salt) resulted in the following junctional maximal single channel current-voltage relationship slope conductances (γ_j in pS): CsCl (153), RbCl (148), KCl (142), NaCl (115), LiCl (86), TMACl (71), TEACl (63). Reversible block of the rCx40 channel was observed with TBA. Potassium anion salt γ_j are: Kglutamate (160), Kacetate (160), Kaspartate (158), KNO₃ (157), KF (148), KCl (142), and KBr (132). Ion selectivity was verified by measuring reversal potentials for current in rCx40 gap junction channels with asymmetric salt solutions in the two electrodes and using the Goldman-Hodgkin-Katz equation to calculate relative permeabilities. The permeabilities relative to Li⁺ are: Cs⁺ (1.38), Rb⁺ (1.32), K⁺ (1.31), Na⁺ (1.16), TMA⁺ (0.53), TEA⁺ (0.45), TBA⁺ (0.03), Cl⁻ (0.19), glutamate⁻ (0.04), and NO₃− (0.14), assuming that the monovalent anions permeate the channel by forming ion pairs with permeant monovalent cations within the pore thereby causing proportionate decreases in the channel conductance. This hypothesis can account for why the predicted increasing conductances with increasing ion mobilities in an essentially aqueous channel were not observed for anions in the rCx40 channel. The rCx40 effective channel radius is estimated to be 6.6 Å from a theoretical fit of the relationship of relative permeability and cation radius.     

Relations of the Al,B, Ba,Br, Ca,Cl, Cu,Fe, K,Li, Mg,Mn, Na,P, S,Si, Sr,and Zn mass fractions to morphometric parameters in pediatric and nonhyperplastic young adult prostate glands

The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid.     

The Effect of Age and Gender on Al, B, Ba, Ca, Cu, Fe, K, Li, Mg, Mn, Na, P, S, Sr, V, and Zn Contents in Rib Bone of Healthy Humans

The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.     

Caprine blood groups. 2. The C,G, H,I, J,K, L,N, and Q systems

Nine blood group systems of goats were identified using 12 caprine reagents produced by absorption of alloimmune antisera. The caprine C blood group system, possibly homologous to the ovine C blood group system, was characterized by two reagents and shown to be controlled by three alleles,C ¹²,C ²⁵, andC ⁻. A more complex blood group system of goats, designated G, was identified using three reagents and shown to be controlled by six codominant alleles (G ^10.19.20,G ^10.19,G ^10.20,G ¹⁰,G ¹⁹,G ²⁰) and a recessive allele (G ⁻). A further seven one-factor two-allelic systems were identified by seven reagents. The nine genetic systems provided exclusion probabilities of 0.479, 0.492, 0.548, and 0.572 in Australian Angora, Dairy, Cashmere, and Texan Angora goat breeds, respectively. This work was supported by a grant from the Australian Stud Book, Alison Road, Randwick, New South Wales 2031, Australia.