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Compensatory growth refers to an animal’s ability to grow extremely rapidly after it has experienced a period of reduced growth. It is also widely held that the growth trajectories of animals showing compensatory growth converge towards those followed by conspecifics that have experienced favorable growth conditions throughout their lives. In other words, it is often assumed that animals undergoing compensatory growth also show some recovery, and thereby exhibit catch-up growth. This belief has resulted in the terms compensatory growth, recovery growth, and catch-up growth being used as synonyms, and has also created some problems with regard to data analysis and interpretation. Following a discussion of methods of analysis and their limitations, a series of growth simulations is presented to illustrate why the terms should not be used as synonyms. The simulations, based upon the assumption that compensatory growth results in a restoration of body composition (using condition index as a surrogate), show that compensatory growth is not always accompanied by a convergence of growth trajectories. Compensatory growth can occur in the absence of catch-up growth, and the simultaneous observation of compensatory growth and a recovery of body mass is a special combination of events. Further, it is possible for growth trajectories to converge even when animals that have experienced a period of reduced growth do not display compensatory growth. Definitions are proposed that distinguish between the terms compensatory growth, recovery growth, and catch-up growth, and guidelines are given relating to the analysis of the results of fish compensatory growth studies.  相似文献   

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The distribution and movement between habitats with growth of the hard clam Meretrix lusoria were examined by comparing the size–frequency distributions among 17 sites in the Shirakawa–Midorikawa Estuary of the Ariake Sea. This clam is a commercially important bivalve in Japan, and its annual catch is largest in the Ariake Sea. At the study sites, new recruits were abundant at river mouths, and density was strongly affected by the distance from coastal tidal rivers and streams. In contrast, adults were widely distributed on tidal flats, although density was low at many sites. At marine site Oda, the density of adults was higher than that of new recruits at all sites and higher than that of juveniles at most sites. These results indicate that this species moves from riverine sites to marine sites with growth. Moreover, the observed low density of adult clams may indicate overfishing. The active movement of M. lusoria across the fishing grounds complicates the sustainable resource management of this species. Therefore, further studies are needed for effective resource management of M. lusoria.  相似文献   

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浅谈鱼类的补偿生长(Compensatory growth)   总被引:1,自引:0,他引:1  
综述了鱼类补偿生长的研究进展,对鱼类补偿生长的定义、类型、特点、影响因素、研究方法、应用、生理机制及补偿生长中的生理生化变化进行了分析。初步探讨了补偿生长研究存在的问题与发展趋势。  相似文献   

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Taga  Makoto  Kamimura  Yasuhiro  Yamashita  Yoh 《Fisheries Science》2019,85(6):931-942
Fisheries Science - The effects of temperature and prey density on the recent growth rate (RGR) of chub mackerel, Scomber japonicus, were examined. Scomber spp. larvae and juveniles were collected...  相似文献   

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The capacity of cortisol, ovine growth hormone (oGH), recombinant bovine insulin-like growth factor I (rbIGF-I) and 3,3,5-triiodo-l-thyronine (T3) to increase hypoosmoregulatory capacity in the euryhaline teleost Fundulus heteroclitus was examined. Fish acclimated to brackish water (BW, 10 ppt salinity) were injected with a single dose of hormone suspended in oil and transferred to seawater (SW, 35 ppt salinity) 10 days post-injection. Fish were sampled 24 h after transfer and plasma osmolality and gill Na+, K+-ATPase activity were examined. Transfer from BW to SW induced significantly increased plasma osmolality but not gill Na+, K+-ATPase activity. Cortisol (50 g g–1 body weight) improved the ability to maintain plasma osmolality and to increase gill Na+, K+-ATPase activity. oGH (5 g g–1 body weight) also increased hypoosmoregulatory ability and gill Na+, K+-ATPase activity. A cooperation between oGH and cortisol was observed in increasing hypoosmoregulatory ability but not in increasing gill Na+, K+-ATPase activity. rbIGF-I (0.5 g g–1 body weight) alone was without effect in increasing salinity tolerance or gill Na+, K+-ATPase activity. rbIGF-I and oGH showed a positive interaction in increasing salinity tolerance, but not gill Na+, K+-ATPase activity. Treatment with T3 (5 g g–1 body weight) alone did not increase salinity tolerance or gill Na+, K+-ATPase activity, and there was no consistent significant interaction between cortisol and T3 or between GH and T3. The results confirm the classical role of cortisol as a seawater-adapting hormone and indicate an interaction between cortisol and the GH/IGF-I axis during seawater acclimation of Fundulus heteroclitus.  相似文献   

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This study investigated the effects of supplementary feeds with different crude protein (CP) levels on the growth and economic performances of sex-reversed Nile tilapia (Oreochromis niloticus) reared in a rain-fed rice–fish ecosystem for a period of 120 days. There were four treatments—namely, traditional feed (21% CP), formulated feed (26% CP), commercial feed (30% CP), and control (no feed was used)—with three replicates per treatment. Fish (30.04 g) were stocked in ditches at a rate of 0.5 fish m?2 considering the total area and fed one of the tested feeds twice daily at the rate of 2%–5% of body weight. Water-quality parameters of the ditches were monitored fortnightly, and these parameters were found suitable for fish farming. Organic matter, total nitrogen, and available phosphorous in soil were increased significantly (P < 0.05) in the feed treatments after fish cultivation. Highly significant weight gain and SGR were observed with fish fed the commercial feed as compared with other treatments. The highest benefit-cost ratio (2.15) was found in the control, followed by formulated feed (1.90), but in the case of numerical net return, it was the opposite. However, commercial feed showed the lowest benefit-cost ratio (1.67) due to higher feed cost than other supplementary feeds. Therefore, this study suggests that fish fed with a formulated feed (26% CP) produced significantly higher net economic return in the rice–fish farming system.  相似文献   

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Shang  Zhenda  Kong  Qinghui  Liu  Suozhu  Tan  Zhankun  Shang  Peng  Wang  Honghui 《Fisheries Science》2020,86(1):87-95
Fisheries Science - Gut microbes are closely related to physical health. The intestinal microbial population in fish is a complicated ecological environment that plays an important role in the...  相似文献   

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The food sources of the main economic animals and trophic levels of biotic communities from an optimized culture model (RhopilemaSinonovacula constrictaParalichthys olivaceusPenaeus chinensis) in a sea water pond in Donggang, Liaoning province were studied using the stable carbon and nitrogen isotopes technique. The results indicated that the values of δ13C range from (?27.28 ± 0.35) ‰ to (?16.65 ± 0.20) ‰ and the values of δ15N range from (3.68 ± 0.23) ‰ to (13.91 ± 0.26) ‰, both of which exhibited significant fluctuations. The δ13C values of P. chinensis, Macrobrachium mipponensis and P. olivaceus were comparatively higher than those of other aquaculture animals, and the δ15N values of P. olivaceus was also comparatively higher. The contribution to the food sources of aquaculture animals (Rhopilema, S. constricta, P. olivaceus and P. chinensis) was analyzed by using the IsoSource software. The results indicated that fish meat had the greatest contribution to Rhopilema, S. constricta and P. chinensis; P. chinensis had the greatest contribution to P. olivaceus, followed by the M. mipponensis. The trophic level of the biotic communities under that optimized culture model in a sea water pond was 3.54, in which P. olivaceus was in the fourth level (3.54); P. chinensis, Synechogobius hasta, Ablennes anastomella, M. mipponensis, Ditrema temmincki Bleeker, Chelon haematocheilus were in the third trophic levels; Rhopilema, Engraulis japonius, S. constricta and zooplankton (1.00) in the second trophic levels, suspended matters (0.15) including phytoplankton, bacteria, humus, etc., were in the primary trophic levels.  相似文献   

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为研究草鱼(Ctenopharyngodon idella)–鳙(Aristichthys nobilis)–鲫(Carassius carassius)零换水池塘营养盐收支状况,阐明其零换水机制,以草鱼–鳙–鲫零换水池塘为实验组,以草鱼–鳙–鲫常规换水池塘为对照组,开展了为期2年的池塘有机碳(TOC)、氮(N)、磷(P)收支的研究。结果显示,2组池塘TOC、N、P的主要来源均为饲料投入,分别为77.06%和81.00%,92.08%和92.77%,94.18%和95.63%;TOC、N、P的主要输出途径均为底泥积累,分别占输入营养盐的43.32%和22.10%,61.40%和52.82%,78.71%和79.58%。2组池塘养殖鱼类收获分别占输入碳(C)、N、P的10.08%和13.05%,21.00%和25.57%,15.41%和18.60%。零换水池塘的C、N、P水体积累量和积累率均显著低于常规池塘(P<0.05),其积累率分别降低92.91%、88.52%和87.12%。零换水池塘的N、P底泥积累量显著高于常规池塘,但C、N底泥积累率显著低于常规池塘(P<0.05),分别降低了48.99%和13.97%。零换水池塘养殖鱼类的C、N、P利用率均显著高于常规池塘(P<0.05),分别提高了29.49%、21.72%和20.65%。研究表明,零换水模式能降低营养盐积累,有效提高系统物质利用率,是一种绿色高效养殖模式,具有较好的推广价值。  相似文献   

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ABSTRACT

The effects of long-term cyclic feed deprivation and refeeding on compensatory growth and body composition of Litopenaeus vannamei were assessed for five different feeding protocols (i.e., 0, 1, 2, 4, 7 days fasting/days feeding) during 15 study weeks. Shrimp in each tank were weighed to calculate growth parameters. The control group has shown the highest specific growth rate (SGR) and the highest final weight compared to the cycling-feeding groups during the first 8 weeks (P < 0.05). On the other hand, during the realimentation period (9–15 weeks), SGR of the cycling feeding groups and the control group are equivalent (P < 0.05). It has been concluded that long-term cycling starvation and feeding treatment lead to compensatory growth of L. vannamei. Final survival rates ranged between 64.4% and 79.9% in all the groups (P > 0.05).  相似文献   

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为探究牡蛎–海参筏式综合养殖模式的可行性,在2个具有代表性的牡蛎养殖区——山东荣成桑沟湾和乳山挂子场海域开展了长牡蛎(Crassostrea gigas)–仿刺参(Apostichopus japonicus)筏式笼养效果对比实验。在牡蛎养殖笼中,奇数层放养长牡蛎,偶数层放养仿刺参。实验设置3个因子:偶数层的底盘类型(普通养殖盘、无孔养殖盘和无孔养殖盘加无节网)、放养仿刺参的密度(1、2和4头/盘)和放养海域(桑沟湾和挂子场),共18个处理组,每组5个重复,实验期为2020年11月—2021年6月。实验期间,对两海域水体6项指标(叶绿素a、颗粒有机物、活性磷酸盐、亚硝酸盐、硝酸盐和铵盐)和实验动物的生长、存活等方面进行跟踪测定和比较分析。结果显示,两海域叶绿素a和颗粒有机物无显著性差异(P>0.05),但其他4项营养盐指标均差异显著(P<0.05)。处理组中,两海域各处理组间牡蛎个体体重及肥满度无显著差异(P>0.05),海参低密度处理组中,海参个体体重及成活率显著高于海参高密度处理组(P<0.05);在其他处理条件相同时,无孔养殖盘处理组的仿刺参个体体重高于普通养殖盘处理组,在挂子场海域有显著差异(P<0.05)。本研究表明,在牡蛎养殖笼偶数层使用无孔养殖盘并放养1头仿刺参,能在降低牡蛎养殖密度的同时,显著提高仿刺参的个体体重和成活率。综上,该牡蛎–海参筏式综合养殖模式可以作为牡蛎规模化养殖区的有益补充  相似文献   

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In this study, we evaluated the effect of diets with various concentrations of estradiol-17β (E2) on the feminization, growth and survival of juvenile fat snook. Over a 45-day period, the juveniles were fed with five diets containing 0, 25, 50, 75 and 100 mg E2/kg feed. Three replicates were run for each diet. After this hormonal treatment, the fishes were transferred to 1-m3 net cages, where they remained for 12 months. During this period, they were fed a commercial diet without added hormones. During the feminization, the control fish grew more than those in the other treatments, and the survival rates did not differ significantly among the treatments. At the end of the experiment growth did not differ among the treatments. In the control treatment, 80.85 % of the fish were male, and the females were significantly larger than the males. All of the treatments with E2 produced 100 % females. No intersex fish were found in this study. This research showed that it is possible to obtain 100 % fat snook females using feeds with 25 mg E2/kg for 45 days without impairing the growth or survival of the fish.  相似文献   

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In this study, the efficacy of heat‐killed Gordonia bronchialis on growth performance, immune system and gastrointestinal structure in rainbow trout (Oncorhynchus mykiss) was evaluated. Fish (mean weight 30 g) were fed basal diet (control), or treatment diets containing 2.48 × 108 (low dose) or 1.24 × 109 (high dose) cells kg?1 feed of heat‐killed G. bronchialis on a pulse basis (5 days on treatment diet; 10 days on basal diet) for 95 days. On days 95 and 105, some of the fish were sampled for analysis of mentioned parameters. On days 110 and 120, the remaining fish were injected intraperitoneally with a 20 mL L?1 suspension of chicken red blood cells. Results showed that growth performance was significantly enhanced in both treatment groups compared with the control group. Serum complement and lysozyme activities and hemagglutination antibody titre were higher in both treatment groups compared with the control group. The length of the intestinal and pyloric caeca folds was increased in the high‐dose group. Meanwhile, the number of goblet cells was increased in both treatment groups. This study suggests that heat‐killed G. bronchialis has the potential to enhance growth, immunological parameters and the gastrointestinal structure in rainbow trout.  相似文献   

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针对当前全球气候变暖趋势,中国提出“双碳”目标,体现了我国主动承担应对全球气候变化责任的大国担当。海洋在实现碳中和目标中具有重要作用。牡蛎礁作为全球海岸带典型生态系统,具有巨大碳储量和强大固碳能力。牡蛎礁在生物钙化、呼吸作用等过程中向大气释放二氧化碳,但在生物合成、沉积作用等过程中却可以埋藏大量碳。目前,全球牡蛎礁是大气碳的源还是汇尚不明确。为探究牡蛎礁碳源–汇功能,本文综述了牡蛎礁碳源–汇功能研究现状,分析了影响牡蛎礁碳 源–汇功能的关键生态过程,探讨了在不同环境条件下牡蛎礁碳源–汇特征。研究表明,牡蛎礁不仅可以成为大气碳的汇,还可以提高盐沼植被、海藻、海洋动物等生物的碳汇功能。未来应尽快开展牡蛎礁碳汇功能评估技术等研究,形成以提高牡蛎礁碳汇为目的的牡蛎礁保护与修复技术,提升我国海洋生态系统碳汇能力。  相似文献   

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