共查询到20条相似文献，搜索用时 31 毫秒
1.
A cost-effective method was designed to measure the behavioral response of negative phototaxis to high-intensity illumination in the sea urchin Glyptocidaris crenularis.Ninety sea urchins were randomly and equally divided into two aquaculture environment groups:a fasted group,which was starved during the experiment,and a fed group.After 10 months,the total mortality of each group was recorded.Then,15 sea urchins were randomly selected from each group and behavioral responses to high-intensity illumination were investigated for each sea urchin.After the behavioral experiment,body measurements of the trial sea urchins were taken.The results reveal that food deprivation significantly affected test diameter(P<0.01),body weight(P<0.01),gonad weight(P<0.01),and gut weight(P<0.01).Furthermore,food deprivation also affected negative phototaxis behaviors of time to rapid spine movement(P<0.01),time to the 1 cm position(P<0.05),and walking distance in 300 s(P<0.01),but not time to body reaction(P>0.05).The mortality rates of fasted and fed urchins were 6.7%and 0%,respectively.The present study provides evidence that food deprivation has a significant effect on phenotypic traits and behavioral responses to high-intensity illumination in the sea urchin G.crenularis.With this method,environmental stressors can be easily detected by measuring proper optional indicators.This study provides a new insight into measuring stress responses of sea urchins in aquaculture.However,further studies should be carried out to understand more environmental factors and to compare this potential behavioral method with immune,physiological,and epidemiological approaches. 相似文献
2.
《中国海洋湖沼学报》2017,(4)
Although it has been hypothesized that a predictable feeding regime in animals allows physiological variables to be adjusted to maximize nutrient utilization and,hence,better growth performance,the assumption has rarely been tested.This study compares the effects of time-restricted versus free access self-feeding on the growth,feeding behavior and daily digestive enzyme rhythms of Atlantic salmon(Salmo salar).In an experiment that lasted 6 weeks,fish(109.9 g) were divided into two groups:group 1 had free access to a self-feeder(FA);group 2 received three meals per day(2 h per meal) at dawn,midday and dusk via a time-restricted self-feeder(TR).At the end of the experiment,the fish were sampled every 3 h over a24-h period.The results showed that the TR fish quickly synchronized their feeding behavior to the feeding window and their blood glucose showed a significant postprandial increase,while FA fish displayed no statistically significant rhythms(P0.05).Pepsin activity of TR fish also showed a significant daily rhythm(P0.05) with the acrophase at the second feed and a decrease over the next 12 h.Average daily trypsin,lipase and amylase levels of FA fish were significantly lower than those of TR fish(P0.01);however,the growth performance of both groups was similar(P0.05).In conclusion,the study failed to confirm a link between the entrainment of daily digestive enzyme profiles and growth performance,with the TR group showing comparatively poor blood glucose regulation. 相似文献
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4.
MAI Kangsen ZHANG Yanjiao CHEN Wei XU Wei AI Qinghui ZHANG Wenbing 《中国海洋大学学报(英文版)》2012,11(4):511-516
An 8-week feeding trial was conducted to investigate the effects of dietary soy isoflavones on feeding intake,growth performance,and digestion of juvenile Japanese flounder(Paralichthys olivaceus).Four isonitrogenous(49% crude protein) and isoenergetic(20.1 MJ kg-1) diets were formulated to contain four graded levels of soy isoflavones,namely,0,1,4 and 8 g soy isoflavones in 1 kg of diet.Each diet was randomly fed to triplicate tanks of fish(Initial average weight:2.58 g ± 0.01 g),and each tank was stocked with 35 fish.No significant difference was observed among diets with levels of 0,1 and 4 g kg-1 soy isoflavones in feed intake,weight gain,feed efficiency ratio(FER),proximate composition of fish whole body and apparent digestibility coefficients(ADC) of nutrients and energy(P>0.05).However,high dietary soy isoflavones level(8 g kg-1) significantly depressed weight gain,FER,whole-body crude lipid content of fish and ADC of nutrients(P<0.05).These results indicate that high level of dietary soy isoflavones(above 4 g kg-1) significantly depresses growth responses and FER of Japanese flounder.However,as the content of soy isoflavones in soybean meal is around 1 to 3 g kg-1,the adverse effects might be neglected when soybean products are used as a fish feed ingredient. 相似文献
5.
Insulin-like growth factors (IGFs) are key regulators of development and growth. Here, we characterized the igf2 gene from olive flounder (Paralichthys olivaceus) and determined its temporal and spatial expression. We set up an in-vitro protein expression system in eukaryotic human embryonic kidney (HEK293T) cells and explored its effects on cell proliferation. The flounder igf2 cDNA contained a 648-bp open reading frame (ORF) encoding a protein of 215 amino acids (aa), which spanned the complete signal peptide (47 aa), mature peptide (70 aa), and E domain (98 aa). In adult flounder, igf2 mRNA was detected in all selected tissues. In early development, igf2 mRNA was detected throughout development from unfertilized eggs to hatching-stage embryos. In-situ hybridization analysis indicated that igf2 mRNA was specially expressed in the brain region, floor plate, hypochord, otic vesicle, and pectoral fin during embryogenesis. Western blotting analysis indicated that the soluble recombinant flounder IGF2 protein was successfully produced through eukaryotic expression in HEK293T cells. In addition, the recombinant IGF2 protein significantly promoted the proliferation of human cervical carcinoma (HeLa) and HEK293T cells. These results provide new information about the structural and functional conservation, expression patterns, and biological activity of the igf2 in teleosts.
相似文献6.
YOU Feng WANG Wei XU Dongdong ZHU Xiangping NI Jing WU Zhihao XU Yongli WANG Xincheng ZHANG Peijun 《中国海洋湖沼学报》2009,27(2)
The hybrid between olive flounder Paralichthys olivaceus and stone flounder Kareius bicoloratus was produced by artificial insemination of olive flounder eggs with stone flounder Sperm. Sinistral and dextral are two types of hybrid progeny after metamorphosis. Karyotypes of both hybrid flounders are the same as those of the two parental species. Of the 22 loci examined from 12 allozymes,12 confirmed hybridization of the paternal and matemal loci in hybrids and no difference was found in allozyme patterns of sinistral and dextral hybrid fishes. RAPD patterns of these specimens were also studied with 38 primers selected from 104 tested. Among them, the PCR products of 30 primers showed hybridization of the paternal and maternal bands. Genetic variation between hybrids and their parental stocks was analyzed by RAPD using 10 of the above 38 primers. The average heterozygosity and genetic distance were calculated. The results suggested that the filial generation could inherit a little more genetic materials from paternal fish than that from maternal fish. 相似文献
7.
Zooplankton constitutes a major part of the diet for fish larvae in the marine food web, and it is generally believed that
copepods can meet the nutritional requirements of fish larvae. In this study, calanoid copepod Schmackeria poplesia, rotifer Brachionus plicatilis and anostraca crustacean Artemia sp. were analyzed for fatty acid contents, and were used as live food for culturing larval Japanese flounder, Paralichthys olivaceus. The total content of three types of HUFAs (DHA, EPA and ARA) in S. poplesia was significantly higher than that in the other two live foods (P<0.01). Three live organisms were used for raising larvae and juveniles of Paralichthys olivaceus respectively for 15 and 10 d. Then the growth, survival and fatty acid composition of the larvae and juveniles were investigated.
The results showed that the larvae and juveniles fed with copepods (S. poplesia) had significantly higher growth rate than those fed with the other two organisms (P<0.01). The survival of the flounder larvae fed with copepods was significantly higher than that of the others (P<0.01), and the survival of the juvenile fish fed with copepods was higher than that fed with Artemia (P<0.05). The contents of three types of HUFAs (DHA, EPA and ARA) and the ratio of DHA/EPA in larval and juvenile flounder P. olivaceus were analyzed. The results showed that the contents of DHA, EPA and ARA in the larvae and juveniles fed with S. poplesia were higher than those fed with a mixed diet or Artemia only, and the ratio of EPA/ARA in larvae and juveniles of P. olivaceus fed with S. poplesia was lower than that in the case of feeding with a mixed diet or Artemia only. The present data showed that copepod is the best choice for feeding the larvae and juveniles of fish considering its
effects on the survival, growth and nutrition composition of the fish. 相似文献
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9.
《中国海洋湖沼学报》2016,(6)
This study examines whether a group of captive false killer whales(P seudorca crassidens) showed variations in the vocal rate around feeding times. The high level of motivation to express appetitive behaviors in captive animals may lead them to respond with changes of the behavioral activities during the time prior to food deliveries which are referred to as food anticipatory activity. False killer whales at Qingdao Polar Ocean World(Qingdao, China) showed signifi cant variations of the rates of both the total sounds and sound classes(whistles, clicks, and burst pulses) around feedings. Precisely, from the Transition interval that recorded the lowest vocalization rate(3.40 s/m/d), the whales increased their acoustic emissions upon trainers' arrival(13.08 s/m/d). The high rate was maintained or intensifi ed throughout the food delivery(25.12 s/m/d), and then reduced immediately after the animals were fed(9.91 s/m/d). These changes in the false killer whales sound production rates around feeding times supports the hypothesis of the presence of a food anticipatory vocal activity. Although sound rates may not give detailed information regarding referential aspects of the animal communication it might still shed light about the arousal levels of the individuals during different social or environmental conditions. Further experiments should be performed to assess if variations of the time of feeding routines may affect the vocal activity of cetaceans in captivity as well as their welfare. 相似文献
10.
ＩＮＴＲＯＤＵＣＴＩＯＮＪｏｈａｎｎｅｓ (1 965)ｆｉｒｓｔｓｈｏｗｅｄｔｈｅｉｍｐｏｒｔａｎｃｅｏｆｐｒｏｔｏｚｏａａｓｒｅｍｉｎｅｒａｌｉｚｅｒｓｉｎｍａｒｉｎｅｅｎｖｉｒｏｎｍｅｎｔｓ.Ｔｈｅｓｉｇｎｉｆｉｃａｎｃｅｏｆｐｒｏｔｏｚｏａｉｎｔｈｅｆｒｅｓｈｗａｔｅｒｆｏｏｄｗｅｂｈａｓｂｅｅｎｋｎｏｗｎｆｏｒｔｈｅｐａｓｔ2 0ｙｅａｒｓ.Ｐｒｏｔｏｚｏａｉｓａｍａｉｎｐｒｅｄａｔｏｒｏｆｐｌａｎｋｔｏｎｉｃｂａｃｔｅｒｉａａｎｄｐｈｙｔｏｐｌａｎｋｔｏｎ ,ａｎｄａｌｓｏａｆｏｏｄｓｏｕｒｃｅｏ… 相似文献
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12.
Effects of Dietary Protein Level on Growth and Utilization of Protein and Energy by Juvenile Mangrove Red Snapper(Lutjanus argentimaculatus) 总被引：1，自引：1，他引：0
1Introduction The mangrove red snapper,Lutjanus argentimacu-latus(Forsskal,1775)is a carnivorous,warm-watereuryhaline fish that is considerably cultured in South-east Asia,Southern China and the Middle East(Le-ung et al.,1999;Estudillo et at.,2000;Ng et al.,2000;Catacutan et al.,2001).In Pakistan,it isknown for its good quality meat and also for its highconsumption rate.Although it fetches a premiumprice at local markets(Anonymous,2002),the in-creasing demand has generated interest towar… 相似文献
13.
Hybrids between olive flounder Paralichthys olivaceus and stone flounder Kareius bicoloratus： karyotype, allozyme and RAPD analyses 总被引：2，自引：0，他引：2
The hybrid between olive flounder Paralichthys olivaceus and stone flounder Kareius bicoloratus was produced by artificial insemination of olive flounder eggs with stone flounder sperm. Sinistral and dextral are two types
of hybrid progeny after metamorphosis. Karyotypes of both hybrid flounders are the same as those of the two parental species.
Of the 22 loci examined from 12 allozymes, 12 confirmed hybridization of the paternal and maternal loci in hybrids and no
difference was found in allozyme patterns of sinistral and dextral hybrid fishes. RAPD patterns of these specimens were also
studied with 38 primers selected from 104 tested. Among them, the PCR products of 30 primers showed hybridization of the paternal
and maternal bands. Genetic variation between hybrids and their parental stocks was analyzed by RAPD using 10 of the above
38 primers. The average heterozygosity and genetic distance were calculated. The results suggested that the filial generation
could inherit a little more genetic materials from paternal fish than that from maternal fish.
Supported by National Natural Science Foundation of China (No. 30571445), National High-Technology Research and Development
Program (863 Program, No. 2006AA10A404), and Project from the Ministry of Science and Technology of China (No. 2006DKA30470-017) 相似文献
14.
Palm oil is of great potential as one of the sustainable alternatives to fish oil (FO) in aquafeeds. In this present study, five isonitrogenous diets (32% crude protein) with elevated palm oil levels of 0%, 2%, 4%, 6% and 8% were used during an 8-week feeding trial to evaluate its effects on RNA/DNA ratio and lipoprotein lipase (LPL) and MyoD mRNA expressions in muscle of Oreochromis niloticus. The results showed that RNA, DNA content as well as ratio of RNA to DNA were significantly affected (P < 0.05), in each case the highest was recorded in fish group subjected to 6% palm oil level. There was a strong positive correlation between nucleic acid concentration (RNA concentration and RNA: DNA ratio) and specific growth rate (SGR), protein efficiency ratio (PER), while a negative correlation existed between nucleic acid concentration (RNA concentration and RNA: DNA ratio) and feed conversion ratio (FCR). The mRNA expressions of LPL and MyoD in muscle were not significantly affected by the different palm oil levels, although the highest expression was observed in fish fed with 6% palm oil level. There also existed a strong positive correlation between the mRNA expression of LPL, MyoD and SGR, PER, while their correlation with FCR was negative. In conclusion, elevated palm oil affected the RNA, DNA concentration as well as RNA/DNA ratio significantly, although the mRNA expression of LPL and MyoD were not affected significantly by elevated palm oil levels. 相似文献
15.
This study examines whether a group of captive false killer whales (Pseudorca crassidens ) showed variations in the vocal rate around feeding times. The high level of motivation to express appetitive behaviors in captive animals may lead them to respond with changes of the behavioral activities during the time prior to food deliveries which are referred to as food anticipatory activity. False killer whales at Qingdao Polar Ocean World (Qingdao, China) showed significant variations of the rates of both the total sounds and sound classes (whistles, clicks, and burst pulses) around feedings. Precisely, from the Transition interval that recorded the lowest vocalization rate (3.40 s/m/d), the whales increased their acoustic emissions upon trainers’ arrival (13.08 s/m/d). The high rate was maintained or intensified throughout the food delivery (25.12 s/m/d), and then reduced immediately after the animals were fed (9.91 s/m/d). These changes in the false killer whales sound production rates around feeding times supports the hypothesis of the presence of a food anticipatory vocal activity. Although sound rates may not give detailed information regarding referential aspects of the animal communication it might still shed light about the arousal levels of the individuals during different social or environmental conditions. Further experiments should be performed to assess if variations of the time of feeding routines may affect the vocal activity of cetaceans in captivity as well as their welfare. 相似文献
16.
To study immune mechanism of fish lymphocyte we performed a proliferation assay and ELISA using monoclonal antibody against
human IL-2. The result showed that an interleukin-2 (IL-2)-like factor was detected in the supernatant of plant haemoglutinin
(PHA)-stimulated lymphocyte culture from peripheral blood, spleen and head kidney of olive flounder,Paralichthys olivaceus. The quantities of IL-2-like factor in the supernatant from different lymphoid tissues were quite different. The IL-2 like
factor in the supernatant from cultured head kidney lymphocytes was much higher than those of peripheral blood lymphocytes
and spleen lymphocytes (P<0.01). The IL-2 activity was found in either mouse thymocyte proliferation assay or flounder head kidney lymphocyte proliferation
assay and shown to have obvious enhancing effect on proliferation of the above two types of cell. The recombinant human IL-2,
(rhIL-2) was able to stimulate flounder thymocyte proliferation and used to detect the IL-2 receptor (IL-2R) on the surface
of flounder lymphocyte. The cross-reaction between the lymphocytes of flounder peripheral blood and CD25(IL-2R) was detected
with flow cytometry and shown that the percentage of CD25-positive cell in peripheral blood was 7.74±0.67%.
This work was supported by National “973” Project G1999012003, G19999012006. 相似文献
17.
Steroid sex hormones, such as estradiol-17β (E2) and testosterone (T), are important regulators of sex change in fish. In
this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gonadal differentiation in the olive
flounder Paralichthys olivaceus using histology and radioimmunoassay (RIA). Flounder larvae were divided into five groups (G0-G4), and fed with 0 (control),
0.2, 2, 20 and 100 mg E2/kg feed from 35 to 110 day post hatching (dph). Fish growth in the G1 and G2 groups was not significantly
different from that of the control group (P>0.05), while fish in the G3 and G4 groups were less active and showed growth depression and high mortality. The gonads of
fish in the G3 and G4 groups were smaller and surrounded by hyperplastic connective tissue. The frequency of females in the
G0-G4 groups was 54.5%, 75.0%, 100%, 100% and 93.3%, respectively. The RIA analyses of E2 and T showed that T levels decreased
during gonadal differentiation, and increased slightly at the onset of ovarian differentiation, while E2 levels increased
gradually and peaked at the onset of ovarian differentiation in the control group. In the E2-treated groups, T levels decreased
before the onset of ovarian differentiation. E2 levels were high on the 48 dph, but declined to a lower level on the 54 dph,
and then increased gradually during gonadal differentiation. And a sharp increase of E2 levels were observed in all E2-treated
groups at the onset of ovarian differentiation. The data suggest that T and E2 play important roles during gonadal differentiation,
and an E2 dose of 2 mg/kg feed could induce sex reversal in P. olivaceus. 相似文献
18.
壳寡糖对吉富罗非鱼幼鱼生长性能、非特异性免疫及血液学指标的影响 总被引：1，自引：0，他引：1
用添加质量分数0.00(对照组)、0.10%、0.30%、0.50%和0.70%壳寡糖的饲料饲喂初始体重(3.81±0.23)g的吉富罗非鱼幼鱼(Oreochromis niloticus)10周,研究不同浓度壳寡糖的添加对吉富罗非鱼幼鱼的生长、非特异性免疫功能以及血脂指标的影响。结果表明:与对照组相比,在4个不同浓度添加组中,添加质量分数0.50%壳寡糖能显著提高幼鱼的增重率(P<0.05)、特定生长率(P<0.05),并降低饲料系数(P<0.05);添加质量分数0.3%和0.5%壳寡糖能显著提高幼鱼抗嗜水气单胞菌感染的能力(P<0.01);添加质量分数0.10%、0.30%、0.50%壳寡糖能显著提高幼鱼血清中碱性磷酸酶活性(P<0.05)。同时,各浓度的壳寡糖均能明显提高幼鱼血清中溶菌酶和超氧化物歧化酶活性以及抗嗜水气单胞菌感染的能力(P<0.05),并降低幼鱼血清中总胆固醇和低密度脂蛋白胆固醇水平(P<0.05)。在本实验条件下,添加壳寡糖可提高吉富罗非鱼幼鱼生长性能、饲料利用率、非特异性免疫功能和调节血脂水平,添加量以质量分数0.30%~0.50%为宜。 相似文献
19.
《中国海洋大学学报(英文版)》2015,(5)
A 12-week feeding trial was conducted to evaluate the effects of dietary stachyose on the growth performance, digestive enzymes activities and intestinal structures of juvenile turbot(Scophthalmus maximus L). Five isonitrogenous(49.58% crude protein) and isolipidic(10.50% crude lipid) diets were formulated to contain 0(Control), 0.625%(S-0.625), 1.25%(S-1.25), 2.5%(S-2.5) and 5%(S-5) stachyose, respectively. With the increase of stachyose level, the growth performance and feed utilization of turbot, such as the specific growth rate, final mean body weight, weight gain rate and feed efficiency, increased significantly(P 0.05) and then stabilized. The feed intake of fish fed S-5 was significantly higher(P 0.05) than that of fish in other groups. The activities of trypsin, intestinal caseinolytic, stomach and intestinal amylase were significantly influenced by stachyose(P 0.05). The highest values of trypsin and intestinal caseinolytic activities were observed in group S-1.25, while the highest activity of stomach amylase and the lowest activity of intestine amylase were observed in group S-5. No lesion or damage was found on the distal intestine structures of fish from all treatments, while the height of simple folds in the distal intestine was significantly increased(P 0.05) when 1.25% or 2.5% stachyose was added in the diets. These results indicated that moderate level of stachyose(1.25%) improves the growth performance, feed utilization, digestive enzyme activities and the distal intestine structures of juvenile turbot. 相似文献
20.
饲料中添加L-肉碱对牙鲆幼鱼生长、生化组成及血液指标的影响 总被引：1，自引：0，他引：1
研究0、300、600、900、1 200、1 500 mg/kg 6个L-肉碱添加水平对牙鲆(Paralichthys olivaceus)幼鱼生长、生化组成和血液指标的影响。结果表明:添加量为1 200 mg/kg的处理组牙鲆幼鱼的增重率和特定生长率显著提高,饲料系数显著降低(P<0.05);随着饲料中L-肉碱含量的增加,肝指数呈现下降趋势,且在添加量为900~1 500 mg/kg时,各组较对照组差异显著(P<0.05);饲料中添加L-肉碱显著降低各实验组脏体比(P<0.05),而对各处理组间存活率和肥满度均无影响(P<0.05);肌肉和肝脏中的脂肪含量与L-肉碱添加量呈负相关,当添加量为1 200~1 500 mg/kg时,较对照组差异显著(P<0.05);肌肉中的蛋白含量与L-肉碱添加量呈正相关,但各组差异不显著(P<0.05);饲料中添加L-肉碱降低血清中的谷草转氨酶、胆固醇、甘油三酯和尿素氮含量,且添加量1 200 mg/kg组各指标含量均显著低于对照组(P<0.05);各处理组的血糖含量较对照组均有所增加,其中1 200 mg/kg组血糖含量较对照组提高41.6%(P<0.05);血清中总蛋白和低密度脂蛋白均随着L-肉碱添加量的增加而呈下降趋势,高密度脂蛋白却得以提升,但差异均不显著(P<0.05)。分析认为,在本实验条件下,饲料中添加L-肉碱可促进牙鲆幼鱼生长,且降脂效果显著。建议L-肉碱最适添加量为1 200 mg/kg。 相似文献