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1.
吴垠 《水产学报》2004,28(6):741-744
The effects of CO2 concentration on the growth and photosynthesis of Dicrateria zhang, jiangensis and Dunaliella sp, in 100 liter air lift photobioreactors were investigated. The results showed that biomass of both algae significantly increased in high CO2 concentration (above 700μL ? L^-1) compared to low CO2 concentration (350μL?L^-1) ,and the culture periods were shorter, However, no significant difference as observed in growth rate when the alga cultured in CO2 concentration of 700μL? L^-1 and 1000μL? L^-1, respectively. These for the maximum photosynthetic rate(Pm) and saturating irradiance level(Ik) of the two species remarkably raised with the elevated CO2 concentration, so was the initial slope(α)of Dunaliella sp.  相似文献   

2.
《齐鲁渔业》2014,(11):I0001-I0001
Added bagasse and Bacillus sp. to Litopenaeus vannamei intensive culture tank, the treatment groups were treatment A(added Bacillus sp.), treatment B(added Bacillus sp. with crushing bagasse) and treatment C(added Bacillus sp. with crushing-steaming bagasse) respectively. To estimate the effect of addition of bagasse with Bacillus sp. on the culture environment and shrimp growth, the level of total ammonia nitrogen(TAN), nitrite nitrogen and nitrate nitrogen, total amount of bacteria in the water and shrimp growth were determined. The result suggested that the TAN concentration in treatment B and C were significantly lower than that in treatment A during the early stage of the culture(P〈0.05). The addition of bagasse with Bacillus sp. was contribute to the formation of bio-floccules. The concentration of bio-floccules in treatment B and Cwere 6.3-20 ml/L and 8.3-30 ml/L respectively, which were significantly higher than that in treatment A(2.7-8.3 ml/L) during the culture(P〈0.05).The average weight of shrimp in treatment B and C were 8.56±0.21g and 8.84±0.26g respectively, which were significantly bigger than that in treatment A(7.66±0.40g) when harvest(P〈0.05).  相似文献   

3.
^60Co-γ射线对成体长牡蛎生长的影响及致死效应   总被引:2,自引:0,他引:2  
刘晓 《水产学报》2005,29(3):424-428
Effects of ionizing irradiation of ^60Co-γ ray on mortality and growth of one year-old Pacific oysters ( Crassotrea gigas ) were studied. Irradiation was conducted at 4℃ and without sea water, and the survival, shell length, shell width, whole wet weight and condition index of irradiated oysters were measured. A biphasic dose response effect of 6^60Co-γ irradiation on Pacific oyster with high stimulatory response dose range to 100 Gy, and strong hormesis effects had been observed. Gamma ray induced mortality happened within 90 days after irradiation, and the relation between dosage ( D ) and mortality at 90 days could be described by the equation of M90 = 0.0041D^2- 0. 1816D (R^2= 0. 9958) with an LD50/90 of 135 Gy, indicating that the Pacific oyster has strong resistance to ^60Co-γ irradiation. Growth in shell length, shell width and whole wet weight of Pacific oyster were also enhanced by 60 Gy of ^60Co-γ ray. The condition index was also enhanced by ^60Co-γ irradiation in the dosage range from 40 to 100 Gy, with the maximum stimulatory response of 2.5 fold of control value at the 40 Gy dosage, suggesting that the accelerating effects of γ ray on growth of the Pacific oyster led to increase in dry meat. Results of this study showed that ionizing irradiation might be useful in the improvement of production traits in shellfish.  相似文献   

4.
水产食品特定腐败菌与货架期的预测和延长   总被引:27,自引:2,他引:25  
杨宪时 《水产学报》2004,28(1):106-111
Fresh fish and lightly preserved fish products are welcome by the global market, however, they are also among the most perishable food products. The research on specific spoilage organisms (SSO) reveals the spoilage process of aquatic product. This paper reviews the current knowledge (past ten years) on SSO of fresh fish and lightly preserved fish products with particular emphasis on characteristics of SSO and how to apply this concept to determine, predict and extend the shelf life of aquatic product. During storage, the microflora changes owing to different abilities of the microorganisms to tolerate the preservation conditions. SSO is defined as special microorganisms which can increase rapidly during preservation and has the ability to produce off- odours and off- flavours associated with spoilage, and spoilage metabolites. Identification of an SSO relies on comparison of the sensory and chemical characteristics of spoiled product with those of isolates from the spoilage microflora. Generally, the SSO of fresh fish may be a single species or genus, but the ones of lightly preserved fish products will be more complex. One exciting area for use of SSO aims to obtain quantitative knowledge about probable behavior of SSO and their function during the progression of spoilage. Thus mathematical models on the growth of SSO are established to evaluate the quality lost degree of product, which provide a sound information for the rational development of devices to monitor loss of products shelf life. Models for the growth of Pseudomonas spp, S. putrefaciens, P. phosphoreum have been established, and validated for shelf life prediction of seafood successfully. Another application field of SSO intends to develop the techniques to prolong the shelf life of food products by inhibiting SSO targetedly. Targeted inhibition of spoilage bacteria during preservation reduces their growth and results in a significant extension of shelf life in despite of the activity of non - spoilage organisms has not been influenced. Such techniques have been applied in perversion field of fresh fish and lightly preserved fish.  相似文献   

5.
《齐鲁渔业》2013,(4):I0001-I0001
Effects of Adding Bacillus sp. Z5 in Diet on Growth, Immune Parameters and Anti-disease Ability of Litopenaeus vannamei
Abstract The el-tects ot addlngBaclllus sp Z5 in shrimp pellet with the amounts of 108CFU/g on growth, immune parameters and anti-disease ability of shrimp Litopenaeus vannamei were studied. The result shows that the shrimps grew faster in Bacillus treatment group and the yield was 24% more than that in the control. After 21 days, the activity of Phenoloxidase in Bacillus group significantly increased. After 42 days,  相似文献   

6.
Tilapia larvae were exposed to 0 (control), 50 (50-Cd) or 100 (100-Cd) μg l-1 cadmium for 4 days and then transferred to cadmium-free fresh water for 3 days of detoxification. Total length and weight, calcium influx and total body calcium and cadmium content were examined at various times during detoxification. All the groups grew normally with regards to total length and body weight. Within the first 12h of detoxification the 50- and 100-Cd exposed groups released cadmium at the similar rate of about 24 ng mg-1 h-1 (or 140 ng larva-1 h-1). Later, however, this rate declined to only 4–16% of the initial level. Calcium influx in the control group showed a 10–26% increase during the detoxification period. Calcium influx in the 50-Cd group increased by about 280% and reached it peak at 12h. Calcium influx in the 100-Cd group increased by 440% and did not peak until 24h after transfer. After peaking, the influxes in both 50- and 100-Cd groups declined to the level of control at the end of the experiment. Calcium contents in 50- and 100-Cd groups increased more rapidly than that in control group within first 24h of the detoxification period. However the rate of increase in calcium content in three groups was the same after 24h. The changes in calcium influx appeared to be correlated with those in calcium content, and these suggested that tilapia larvae regulate the mechanism of calcium balance to compensate for the reduced calcium level in the body. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

7.
绿色微囊藻等不同食物对大型生长和脂类成分的影响   总被引:1,自引:1,他引:0  
王丽娟 《水产学报》2006,30(6):843-847
The growth and reproduction of Daphnia magna fed with Microcystis viridis and Chlorella spp respectively and 20% fish oil + 80% yeast and yeast were studied. The intrinsic rate of natural increase of Daphnia magna (rm) was 0.243 fed with Microcystis viridis, 0.301 with Chlorella spp., 0.244 with 20% fish oil + 80% yeast and 0.193 with yeast. The result showed that:Daphnia magna fed with Microcystis viridis had lower growth rates than that fed with Chlorella spp. an d 20% fish oil + 80% yeast which both had full fatty acids. And the Daphnia magna fed with yeast was the lowest. So the fatty acids composition of diet may affect the growth of Daphnia magna. This paper further examined total lipids and main HUFA (EPA and DHA) compositions of the continuous three generations of Daphnia magna (in order to get rid of t he effects of former diet) fed with different of above diets (except the yeast). The result showed that:the three generations of the D. magna fed with Microcystis viridis had the lowest total lipids and the percentages of the HUFA (EPA, and no DHA) have a significant decrease and get the lowest EPA in the final experiment because of the very low HUFA especially EPA and DHA in Microcystis viridis. So the results indicate that Microcystis viridis with low HUFA made the lower growth rate, spawn ing rate and hatching rate of Daphnia magna.  相似文献   

8.
美洲黑石斑鱼营养成分分析与营养价值评价   总被引:4,自引:0,他引:4       下载免费PDF全文
In this experiment, the contents of the main nutrients such as protein, fat, moisture, ash, calcium and phosphorus were analysed, and the contents of the trace elements, amino acids and fatty acids in its muscle were determined for Centropristis striata. Moreover, its nutritional value was evaluated and compared with other fishes,livestocks and poultries. The results showed that the content of dry matter and protein are higher in its muscle. Then, all of 17 common amino acids(AA) contents in muscle was 17.51% in the fresh sample, and 7 of them are human essential amino acids(EAA)41.58% in the total amino acids(TAA). The ratio of essential amino acids to nonessential amino acids(EAA/NEAA) was 84.46% ,and the essential amino acids index(EAAI) was 57.71. According to AAS and CS,which basically accorded with the issued standard value by FAO and WHO. The content of 5 delicious amino acids was 44.37% in the TAA, and the ratio of branched chain amino acids to aromatic amino acids was 2.83. The content of polyunsaturated fatty acids was 22.3% rich in its muscle also, in particular EPA and DHA. In conclusion, Centropristis striata is a species of delicious and high nutritional value,which well deserves exploitation and utilization. At the same time, this experiment was preparing for the next study to provide reference data for artificial feed and the expansion of aquaculture.  相似文献   

9.
The biological cleaning agent Pondplus was dowsed each ten days at different dosage into breeding ponds for Chinese mitten crab with stocking rate at 12 000 ind./ha, to evaluate its purification effects on water environment in breeding ponds and its effects on Chinese mitten crab growth. The results showed that dousing treatment improved the water quality significantly as evaluated according to the parameters of DO, CODMn, NH4 + - N and NO2 - -N. Particularly, when the air temperature was higher than 35℃, the diurnal observation on DO values at the bottom of ponds showed that dousing at 450 g/( ha•m) gave a DO value higher than 4 mg/L all day long, which was 2 mg/L higher than that of control. The observed increase of Chinese mitten crab were 14. 9% , 27.8% , 27.8% by average weight, when dousing at 150, 300, 450 g/(ha • m) , respectively. Accordingly, the production increased by 8.5%, 11.9%, 18.6% through its promotion of Chinese mitten crab growth, and the economic efficiency were enhanced by 96.2% , 159.8% , 180.9%.  相似文献   

10.
杨严鸥 《水产学报》2006,30(4):571-576
In order to investigate the difference in utilization of diets with different quality in Jian carp(Cyprinus carpio var. Jian)and allogynogenetic silver curcian carp(Carassius auratus gibelio), a 55 d growth trial was conducted and low quality diet (LQ-diet) and high quality diet (HQ diet) were tested. LQ-diet contained 33.91% dietary protein which is mainly from soybean meal while HQ-diet contained 45.59% dietary protein which is mainly from fish meal. The initial average body weights were from 5.58 g to 5.82 g for two fish strains. The trial was carried out in a system consisting of 12 self circulation 320 L tanks. During the experiment, the fish were fed to satiation twice a day (at 9: 00 and 15:00), and uneaten feed was collected 1 h after feeding and dried. Feces were collected twice a day (at 11:00 and 16:45) from the fecal traps and dried at 70 ℃. The results show that feed intake was higher in Jian carp than in allogynogenetic silver curcian carp when fed LQ diet, while there was no significant difference between weight gain, feed conversion efficiency, protein efficiency rate and apparent digestibility. When fed HQ diet, Jian carp showed a lower feed intake, but higher feed conversion efficiency and protein efficiency rate than allogynogenetic silver curcian carp while there was no significant difference in the weight gain and apparent digestibility of both species. For Jian carp, feed intake and protein efficiency rate for the fish fed HQ diet and LQ diet were not significantly different, while the fish fed HQ diet showed higher weight gain, feed conve rsion efficiency and apparent digestibility. For allogynogenetic silver curcian carp, the fish fed HQ diet showed significantly higher feed intake, apparent digestibility, weight gain, feed conversion efficiency and lower protein efficiency rate. For Jian carp, body contents of dry matter, protein, lipid and energy for the fish fed HQ diet and LQ diet were significantly higher. For allogynogenetic silver curcian carp, body contents of dry matter and protein was significantly higher, while body contents of lipid and energy were affected by diet qualities. Compared to Jian carp, allogynogenetic silver curcian carp showed better utilization when fed LQ diet while poorer utilization when fed HQ diet.  相似文献   

11.
The oogenic cycle and biochemical composition of the ovary of raft-cultured great scallop (Pecten maximus) were studied during the period April 1990–July 1991. The ovary condition index (FGI) and stereological studies showed the existence of two principal spawning periods, winter and late spring-early summer. No sexual resting period was found. Oocyte lysis was high throughout the year. Ovarian lipid levels displayed a clear seasonal pattern linked to the gametogenic cycle. Total lipid (TL, 16–21% dry weight), acylglycerol (AG, 20–65% TL) and free sterol (FS, 2.8–6.4% TL) levels were, generally, higher in the ripe ovary and a decrease coincided with spawning. Protein (59–63% dry weight), glycogen (<3% dry weight) and phospholipid (PL, 26–35% TL) levels showed no clear seasonal trend. The TL and AG were a good index of ovarian sexual maturity. The TL % of dry weight) correlated well with the female gonad condition index (r s = 0.779, p < 0.001), and AG (% f TL) correlated well with the mean oocyte diameter (r s = 0.630, p < 0.01) and the female gonad condition index (r s = 0.443, p < 0.05).  相似文献   

12.
温度对三疣梭子蟹行为的影响   总被引:1,自引:0,他引:1  
描述了三疣梭子蟹的摄食、领域、防御、攻击及清洁行为。三疣梭子蟹在水温12℃以上摄食行为加强,领域与攻防行为也很明显,攻防主要其螯肢。三疣梭子蟹的清洁行为比较复杂,在光强度变化较大时较为明显,一般要持续15~20min。随着温度的降低,三疣梭子蟹的摄食、攻防、领域行为都明显减弱。  相似文献   

13.
沸石在河蟹育苗中的应用   总被引:4,自引:0,他引:4  
宋继周 《齐鲁渔业》1999,16(3):10-11
在河蟹育苗中,利用沸石作水质净化剂.从幼体蚤状Ⅲ期始,每天在3个幼体培育池共90m3水体中投放200×10-6沸石。结果试验组每m3水体大眼幼体出苗量增加54g,效果明显。试验证实,投放沸石能吸附水中有机污染物,降解氨氮,净化水质,促进幼体正常变态发育。  相似文献   

14.
辽宁是重要渔业省份之一,海岸线较长,渔船渔港众多,全省沿海25个县(市、区)拥有渔民20余万人,各类渔船3万多艘。长期以来,因海上生产条件差,环境极其恶劣,渔船比较分散,管理难度越来越大,渔业安全生产形势十分严峻,各类渔船海损事故频繁发生,给渔民造成极大损失,  相似文献   

15.
沙门氏菌是一类革兰氏阴性、长有鞭毛的兼性需氧菌,多数存在于动物的排泄物中,其引起食物中毒的发病率极高.本文对沙门氏菌的三种主要检测方法:微生物学检测法、酶联免疫吸附法、PCR快速检测技术的实验方法、注意事项以及优缺点进行探究,对于更为准确快速鉴定沙门氏菌,防止沙门氏菌进一步蔓延具有一定的意义.  相似文献   

16.
利用渔港改造,加快推进游艇公共码头建设步伐   总被引:1,自引:0,他引:1  
历史上形成的渔港产业体系与传统服务格局,已远不能满足渔港产业延伸要求,更与当今快速增长的新兴海洋休闲旅游发展需求及城市游艇公共服务设施建设未能同步,国内渔港在现代渔业建设的推动下正面临着产业转型与升级问题。笔者认为,当前是我国游艇产业发展的重要关口,尤其是加速游艇公共码头建设,对促进游艇内需的销售与游艇消费将具有不可低估的持续影响力,而利用当前渔港改造和产业提升机会,应是加快游艇公共码头建设步伐,推进地方游艇产业发展的最佳选择。各沿海城市政府主管部门可以通过加大对渔港产业整合力度、统筹规划与合理布局、模式创新与拓宽资金渠道等措施,妥善调整好各种利益关系,以期实现渔港城(镇)市包括游艇业在内的整体产业升级。  相似文献   

17.
牛蛙爱德华氏菌病病原菌的鉴定和致病因素的研究   总被引:6,自引:1,他引:5       下载免费PDF全文
从患爱德华氏菌病的牛蛙肌肉、肝、肾、血液和腹水中分离到8株细菌,根据其形态和生理生化特性鉴定为野生型迟钝爱德华氏菌。人工感染实验均为该病的病原菌,毒素检测试验表明,致病因素主要是内毒素而不是外毒素。分离菌株的主要特性为杆状、革兰氏阴性、周生鞭毛、兼性厌氧。接触酶、甲基红试验和硝酸盐还原均为阳性。在三糖铁琼脂上产H2S。氧化酶、丙二酸盐利用、V.P试验、明胶液化、尿素酶。苯丙氨酸脱氨酶为阴性。分解葡萄糖、甘露糖、麦芽糖,产酸产气,不利用甘露醇、蔗糖和阿拉伯糖。  相似文献   

18.
海洋生物资源的可持续开发和利用已成为全球海洋生物资源管理的重心。预警原则作为一种新颖的环境资源管理手段,其对海洋生物资源养护的有效性已为一些国际协定和一些国家的国内立法所确认。目前我国海洋生物资源管理实践和相关法规并没有明确采用预警原则。因而,针对我国近海生物资源养护不利的现状,我国有必要增订相关立法,将预警原则规定为我国海洋生物资源管理的基本原则,并根据我国各海域的具体情况,有针对性的适用预警原则,以顺应全球海洋生物资源养护的大趋势。  相似文献   

19.
进行了美国杂交条纹鲈的苗种培育试验,科学调节池塘水体理化因子,初步探讨了美国杂交条纹鲈生长的适宜生态条件。认为美国杂交条纹鲈适温范围广,苗种培育过程中溶解氧应在4mg/L以上,碱度、硬度保持3me/L左右,pH8.0以上,COD应在10mg/L以下,对氮、磷营养元素和苗种培育饵料生物也进行了分析。  相似文献   

20.
用8种弧菌对斑节对虾受精卵和无节幼体进行感染试验,结果表明,8种弧菌严重地影响虾卵的孵化和幼体的正常发育,其中以混合弧菌感染致病性最强。试验还显示了弧菌对越是早期的胚胎侵害力越强。  相似文献   

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