麦饭石对养殖水体中藻类光合作用强度影响的试验↑（*）

本文报道了麦饭石对养殖水体中藻类的光合作用强度及对其生长发育的影响。最佳添加浓度为２０ｐｐｍ，密闭培养７２小时后，光合作用强度比对照组提高了６１％，浮游植物生物量比对照组增加４１．４毫克／升，硅藻在总生物量中的所占比例比对照组提高了１７％，试验表明，麦饭石是池塘养殖用优质微肥之一     

沸石矿补剂饲料对池养草鱼生长及某些生理指标的影响

在鱼饲料中添加5%沸石粉,或用2.5%沸石粉+2.5%过磷酸钙。草鱼在生长、肥满度、背肌成份、消化率、血红蛋白等项指标上均比未添加沸石粉的对照组好,两者以2.5%沸石粉+2.5%过磷酸钙组效果更好。     

豆粕(饼)的真伪鉴别法

豆粕适口性好，粗蛋白含量高，氨基酸组成较为全面，是养殖业中重要的蛋白质补充饲料，但近年来，豆粕搀假的事情时有发生，给养殖业造成损害。下面我们介绍一下豆粕的真伪鉴别的方法。1．搀假豆粕的主要搀杂物及外观特点搀杂：豆粕的搀杂物常见的有泥沙、沸石粉及其它盐酸不溶物、玉米粒、玉米秸等。其中沸石类物质占搀杂量的绝大多数一般添加5％－10％的沸石粉，降低豆饼蛋白质含量至30％。外观特点：沸石粉类物质本身呈现灰白色，容重大，玉米破粹后颜色与豆粕十分接近，不法商人把这些物质与少量纯豆粕混合后，用机器压制成片，再破…     

添加外源性促生长剂对河蟹生长的影响

为了弄清外源性促生长剂对促进河蟹生长的效果，将100×10~(-6)甲基睾丸酮、1％沸石粉、1‰中草药粉以及1‰两种市售虾蟹脱壳促生长剂加入基础饲料中，制成5种试验饲料，喂养每只为12g的幼蟹21天。结果：添加甲基睾丸酮和沸石粉组，幼蟹的增重率与对照组相比，差异不显著（P＜0．05）；而添加中草药及2种市售脱壳促生长剂组幼蟹的增重率显著低于对照组（P＜0．05）．说明对河蟹的生长有一定的抑制作用。分析了这种结果的原因，认为不应当盲目地在幼蟹配合饲料中添加外源性蜕壳激素。     

渔用中药药剂防治黄鳝寄生虫病的研究

以使君子、百部、贯众和榧子配制驱虫药。4味药中，使君子的功效最高，4味药以使君子4％、百部10％、贯众20％、榧子15％的比例配成的驱虫药效果最好，寄生虫检出率只有10％，比对照组降低了87．5％。     

豆粕(饼)的真伪鉴别法

豆粕适口性好，粗蛋白含量高，氨基酸组成较为全面，是养殖业一种重要的蛋白质补充饲料，但近年来，豆粕搀假的事件时有发生，给养殖业造成损害。下面我们介绍一下豆粕的真伪鉴别的方法。1：搀假豆粕的主要搀杂物及外观特点搀来：豆粕的搀杂物常见的有泥沙、沸石粉及其它盐酸不溶物、玉米粒、玉米秸等。其中佛石粉类物质占搀杂量的绝大多数（一般添加5％－10％的沸五粉，降低豆饼蛋白质含量至3O％）。外观特点：沸石粉类物质本身呈现灰白色容重大，玉米破碎后颜色与豆粕十发接近，不法商人把这些物质与少量纯豆粕混合后，用机器压制成片，…     

广东紫菜和坛紫菜温度适应性的比较研究

在本文中介绍了用瓦勃氏微量呼吸检压仪对同一海区养殖的广东紫菜和坛紫菜叶状体的暗呼吸强度及光合作用强度的测定结果；并对两种紫菜的单位产量作了比较。结果证明，广东紫菜比坛紫菜更适应于在我国南方水温较高的海区养殖。     

罗氏沼虾饲料中添加青霉素药渣的效果

采用梯度法分别在配合饲料中添加５％、１０％、１５％和２０％的青霉素药渣，制成直径２ｍｍ的颗粒饲料饲养罗氏沼虾。试验结果表明，饲料中添加５％的青霉素药渣，罗氏沼虾的增重率比对照组高２５．２％；添加５－２０％的青霉素药渣，试验虾的存活率大于（或等于）对照虾，其中添加１５％青霉素药渣的试验组，沼虾的存活率最高。     

单细胞蛋白饲喂肉种鸡试验

在产蛋期，对艾维茵肉用种鸡饲喂6％单细胞蛋白粉代替3％鱼粉、3％豆饼，添加必需氨基酸，在营养水平一致的情况下,其饲料的价格试验组比对照组低0.12元／公斤，通过本试验，试验组日均产蛋率、月均存活率、种蛋受精率比对照组低0.55％、0.19％、0.96％，差异均不明显（P＞005），只均产值试验组比对照组优3.57元，只均利润试验组比对照组低1.65元，由于两栋鸡舍面积一样大，采用只均平摊分配法，试验组比对照少存栏211．5套，所以只均利益少，如果单独与饲料对比，则试验组比对照组多盈利1.88元。     

一种紫色非硫光合细菌对硫化物的抑制及其在对虾养殖中的应用

本文报道一种紫色非硫光合细菌能够减少污染水体中硫化氢的发生量，硫化物最高检测浓度降低３７．８％，总检出量减少４８．３％，统计检验结果表明作用效果显著。在室内养虾试验两个月后５０，１００ｐｐｍ菌液浓度组，底泥硫化物含量分别比对照组减少８２．１％和３８．０％。应用于生产性对虾养殖池，池水具有透明度降低，ｐＨ稳定，溶氧增加的水质特征，具有很好的应用前景。     

Effects of light intensity on the photosynthetic responses of Sargassum fusiforme seedlings to future CO2 rising

Mariculture of the economically important seaweed will likely be affected by the combined conditions of ocean acidification that resulting from increasing CO₂ rising and decreased light levels, especially under high culture intensity and high biomass accumulation. To examine this coupling effect on the photosynthetic performance of Sargassum fusiforme seedlings, we cultured seedlings of this alga under different light and CO₂ levels. Under low light conditions, elevated CO₂ significantly decreased the photosynthesis of S. fusiforme seedlings, including a decreased photosynthetic electron transport rate. Seedlings grown under the low light intensity exhibited higher photosynthetic rates and compensation irradiance, and displayed higher photosynthetic pigment contents and light absorption than seedlings grown under high light intensity, providing strong evidence of photosynthetic acclimation to low light. However, the captured light and energy were insufficient to support photosynthesis in acidified seawater regardless of increased dissolved inorganic carbon, resulting in declined carbohydrate and biomass accumulation. This indicated that S. fusiforme photosynthesis was more sensitive to acidified seawater in its early growth stage, and strongly affected by light intensity. Future research should evaluate the practical manipulation of biomass accumulation and mariculture densities during the early culture period at the CO₂ level predicted for the end of the century.     

收割强度对粉绿狐尾藻生长和水质的影响

研究5种收割强度对粉绿狐尾藻生长和水质的影响,为沉水植物调控管理提供参考。设不收割组作为对照组,收割组收割强度分别为株高的15%、30%、45%、60%和75%。将收割的植物称量干重和鲜重,统计株高、分枝数,测定新生枝条的恢复长度。每次收割前1 d对所有处理组的水样进行水质测定。结果表明:(1)收割对粉绿狐尾藻枝条生长恢复和株高影响显著(P<0.01)。对照组最终株高最高,达到187.0 cm,并在水面形成冠层。第1次收割后20 d,低强度(15%和30%)收割组恢复或超过收割前水平,中强度(45%)收割组枝条全部恢复,但高强度(60%和75%)收割组的恢复率明显低于低、中强度收割组,恢复率分别为80.68%和62.00%。第2次收割后20 d,15%和30%收割组的粉绿狐尾藻全部恢复,45%收割组的恢复率为91.44%,高强度收割组的恢复率明显降低,恢复率分别为76.09%和42.22%,至实验结束时高强度收割组都未恢复。随着收割频次的增加,枝条恢复的时间延长。(2)收割减少了粉绿狐尾藻分枝数。对照组分枝数最高,达到6.9枝/株,15%~75%收割组分别为4.3、4.0、3.6、2.2和1.8枝/株。(3)收割显著降低了粉绿狐尾藻的生物量(P<0.01)。15%~75%收割组的生物量分别下降为对照组的10.11%、3.23%、2.47%、2.29%和0.80%。(4)粉绿狐尾藻收割对水质影响显著。收割后,水体中总氮、总磷浓度降低,且收割强度与收割次数对氮磷浓度影响显著(P<0.01)。与第1次收割相比,第2次收割后,15%收割组总氮、总磷浓度分别较前次下降13.63%和24.82%,30%收割组下降12.90%和22.87%,45%收割组下降8.24%和25.04%,高强度(60%和75%)收割组下降6.66%和34.91、9.64%和17.64%。收割强度会对水体中悬浮颗粒物(SS)和叶绿素(Chl-a)有影响,高强度收割使得水体中的SS和Chl-a含量明显升高。收割对控制粉绿狐尾藻生长效果明显,结合水质指标,以低强度收割2~3次为宜。     

微生物固定化载体筛选及其水质处理效果研究

为得到吸附能力强、水质处理效果良好的微生物固定化载体,本实验沸石、火山石、陶环、核桃壳、牡蛎壳五种不同载体对蜡样芽孢杆菌(Bacillus cereus,NY5株)的负载性能,以及在以养殖废水作为空白对照,游离NY5作为阳性对照的条件下,不同载体固定NY5对养殖的处理效果,并利用主成分分析法对水质处理效果进行综合评价。结果显示:沸石和牡蛎壳对NY5的负载性能较好,载菌量分别达1.25×10~9、9.0×10~8CFU/g;在养殖废水处理方面,火山石NY5组第7天、牡蛎壳NY5组第21天时NH_4~+-N浓度与空白对照相比分别降低53.4%、56.6%;火山石NY5组第7天时NO_3~--N浓度与空白对照相比降低87.9%;第28天时火山石NY5组、牡蛎壳NY5组NO_2~--N浓度与空白对照相比分别降低90.1%、80.2%;第14天时火山石NY5组TN浓度与空白对照相比降低51.6%。从主成分分析的结果也可以看出,火山石NY5组和牡蛎壳NY5组对养殖废水综合处理效果较好。     

补充CO2对光生物反应器培养新月菱形藻的影响

为了优化光生物反应器培养微藻的条件, 研究了在充空气的基础补充CO2 对光生物反应器培养新月菱形藻(N itz schiaceae clos terium )生长和光合作用的影响。实验表明, 补充CO2 (含1 000LL /L CO2 的空气)促进新月菱形藻的生长, 藻细胞密度和生物量显著高于对照组( CO2含量350LL /L) (P < 0. 05)。补充CO2 也能够提高藻细胞叶绿素a和类胡萝卜素的含量(P < 0.05),但是对叶绿素b没有显著影响(P > 0. 05) 。补充CO2 能够显著提高指数生长期的最大光合速率( Pm )、光合作用效率( A) 和光合作用饱和光强( Ik ) (P < 0. 05)。结果表明, CO2是光生物反应器培养微藻的限制因子之一, 补充CO2 能够提高微藻的生物量。     

Influence of nanochitosan/zeolite composite on growth performance,digestive enzymes and serum biochemical parameters in rainbow trout (Oncorhynchus mykiss)

Protective effects of nanochitosan/zeolite composite besides zeolite and chitosan/zeolite composite on rainbow trout growth, digestive enzyme activities and biochemical parameters were studied. Nanochitosan/zeolite hybrid composites with three different ratio of nanochitosan:zeolite (35:100, 3.5:100 and 0.35:100) were synthesized and analysed by X‐ray powder diffraction (XRD), thermal gravim (TG) analysis and scanning electron microscope (SEM) methods. Prepared composites as well as zeolite and control diets were fed to rainbow trout (50 g) for a period of 60 days. The addition of treated diets significantly improved growth performance compared to the control diet. Supplemental zeolite could only enhance the amylase activity in fish intestine, whereas other treatment groups could increase the pepsin activity besides intestinal alkaline phosphatase, trypsin and amylase activities. No differences were observed for intestinal acid phosphatase and lipase activities among the experimental diets. Meanwhile, serum total antioxidant activity and lipid peroxidation product, indicated by malondialdehyde (MDA), significantly increased and decreased, respectively, with some doses of administration, indicating the elevated antioxidant status in treatment groups. Serum‐specific marker enzymes, namely aspartate aminotransferase (AST) and alkaline phosphatase (ALP), were not affected in all groups. Meanwhile serum total protein in most treatment groups was significantly higher than the control group. Results showed that synthesized composites especially nanochitosan/zeolite composite at 5 g/kg had potential to enhance growth performance, digestive enzyme activities and some biochemical parameters in rainbow trout.     

水体光照强度的变化对浮游甲壳动物群落结构的影响

近年来,我国淡水湖泊富营养化现象日益严重,藻类大量生长导致水体光照强度减弱,水生植物严重衰退。为了解水体光照强度减弱对生活在沿岸带草丛中的浮游甲壳动物分布情况的影响,本研究于2015年5月至2015年11月在水族箱中通过移植苦草并覆盖不同层黑色遮阳布来建立4个光照梯度（L1- L4）,其透光率分别是40.5%、17.1%、7.1%和2.8%,来模拟自然条件下沿岸带浮游甲壳动物群落对低光压力的响应,分析了水体理化指标、苦草和浮游甲壳动物群落结构变化。结果表明：（1）从不同的光照处理来看,浮游甲壳动物生物量随光照强度减弱而减少,其平均值分别是1.27 mg/L、0.99 mg/L、0.95 mg/L和0.45 mg/L,丰度和多样性也随光照强度减弱逐渐降低;（2）与其他3个处理组相比,L4组中除了锯缘真剑水蚤相对生物量百分比从5%升高到25%,其他种类都有所下降,其中晶莹仙达溞从50%降至9%;（3）浮游甲壳动物的平均生物量在秋季（1.28 mg/L）大于夏季（0.54 mg/L）,而夏季（83.79 ind./L）平均丰度大于秋季（53.59 ind./L）。统计分析表明浮游甲壳动物群落结构变化与光照强度和苦草生长引起的水体理化的变化显著正相关,主要是溶解氧和pH值。     

Intestinal histology and stereology in rainbow trout (Oncorhynchus mykiss) administrated with nanochitosan/zeolite and chitosan/zeolite composites

In previous study, the effects of synthesized chitosan/zeolite and nanochitosan/zeolite composites on rainbow trout growth, digestive enzyme activities and some biochemical parameters were shown. In this study, the effects of experimental diets based on the previous study on the rainbow trout intestinal histology and stereology were assessed: control diet (no zeolite and composite), T1 diet (14.28 g/kg zeolite), T2 diet (0.05 g/kg chitosan included in zeolite), T3 diet (0.5 g/kg chitosan included in zeolite), T4 diet (5 g/kg chitosan included in zeolite), T5 diet (0.05 g/kg nanochitosan included in zeolite), T6 diet (0.5 g/kg nanochitosan included in zeolite), T7 diet (5 g/kg nanochitosan included in zeolite). The experiment was conducted for 60 days. Results showed that supplemental diets did not have side effect on the normal structure of intestinal segments but administration of T1 and T4 diets had slight negative effects on structural maintenance in the middle part of intestine. Acidic mucin producing goblet cell percentage was also higher in nanocomposites‐administrated groups in comparison with the control group. Enhanced villus height, density and finally absorption surface area in different parts of rainbow trout intestine were mainly shown in T7 group. Meanwhile, higher thickness of tunica mascularis in different regions were noted in treatment groups especially in T7 group. The number of intraepithelial mononuclear leukocytes in fish intestine received treatment diets was also higher than control group. In conclusion, nanochitosan/zeolite composites in comparison with zeolite and chitosan/zeolite composites were more effective to improve histological structure of rainbow trout intestine.     

Use of biomass of the marine microalga Isochrysis galbana in the nutrition of goldfish (Carassius auratus) larvae as source of protein and vitamins

The effect of the replacement of fish protein hidrolizate and vitamin premix by freeze‐dried biomass of the marine microalga Isochrysis galbana in the feed for goldfish (Carassius auratus) larvae was tested. Larvae (3.4±0.7 mg) were fed with three experimental microparticulated diets that differ from each other in the percentage of replacement of fish protein hidrolizate (25% or 100%) or vitamin premix by I. galbana biomass. The control diet and the diet containing microalgae biomass as a substitute of 25% of fish protein hidrolizate (MP₂₅) presented the highest survival, being almost 100%, with no significant differences between them. Survival in diets in which 100% of fish protein hidrolizate (MP₁₀₀) or vitamin premix (MV) had been substituted by microalgal biomass was 78% and 66% respectively. Growth, measured as weight, was lower than with the control diet in all treatments in which microalgal biomass was included, with lowest results being obtained with the MP₁₀₀ diet. Differences between treatments and control were lower when growth was measured as length. The harvesting and processing microalgae biomass is crucial to maintain the nutritive value and could be the cause for the obtained results.