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151.
Ming He Xiaoqin Li Lumpan Poolsawat Zihao Guo Wenxiang Yao Chunyan Zhang Xiangjun Leng 《Aquaculture Nutrition》2020,26(4):1058-1071
This study was conducted to investigate the effects of replacing fish meal (FM) with fermented soybean meal (FSM) and soybean meal (SM) on growth performance, intestinal histology and microbiota of largemouth bass (Micropterus salmoides). The basal diet contained 350 g/kg FM (CON), and then, FM was replaced with SM and FSM at the ratios of 30% and 60% (SM‐30, SM‐60, FSM‐30 and FSM‐60), respectively. The largemouth bass (4.43 ± 0.13 g) were fed for 8 weeks. The results showed that weight gain of fish fed with FSM‐60 and SM‐60 diets was significantly lower, and feed conversion ratio of SM‐30, SM‐60 and FSM‐60 groups was significantly higher than the CON group (p < .05). The intestinal villus height of SM‐60 group and the villus width of SM‐60 and FSM‐60 group were significantly lower than the CON group (p < .05). The 30% FM replacement by SM and FSM significantly increased the abundance of Cetobacterium and Mycoplasma, respectively (p < .05). In conclusion, FSM could replace 30% FM in diet without negative impacts on the growth performance of largemouth bass, while the SM should be controlled below 30%. 相似文献
152.
Fagner Machado Ribeiro Mrio Lima Pedro Aurlio Tataíra da Costa Diego Machado Pereira Thony Assis Carvalho Tadeu Vilela de Souza Hortência Aparecida Botelho Fabyano Fonseca e Silva Adriano Carvalho Costa 《Aquaculture Research》2019,50(7):2004-2011
The objective of this work was to evaluate the association between morphometric variables and carcass characteristics in Pirapitinga. We used a thousand specimens of Pirapitinga with an average weight of 1,200 g, which were stunned, slaughtered, weighed, measured, and processed for morphometric and processing yield analysis, to obtain weights, carcass and fillet yields. Initially, the linearity of the variables was verified. Pearson's simple and partial correlation tests were performed between all metrics. Track analysis was performed considering the weights and yields of carcass and filet as dependent variables and the others as independent variables. Ridge regression models were used to eliminate the effects of multicollinearity among the independent variables. Observations showed that the simple correlations between body weights and yields were superior to the partial ones in terms of magnitude. The length and circumference of the specimens were the measures most linearly associated with weight, carcass weight and fillet with rib weight. As for carcass yield and fillet yield, linear correlation coefficients were low and not significant when associated with body weights. With the path analysis, we could observe significant positive correlations between the morphometric measurements for weight, carcass weight and fillet with rib weight. The standard length, body circumference and body circumference/body height ratio are the most correlated. The latter are the most important variables in the evaluation of body weights in Pirapitinga fish. They can serve as criteria for indirect selection in searching for fish with better carcass characteristics. As for fillet and carcass yields, the morphometric variables have not shown to be efficient for indirect selection. 相似文献
153.
Marine fisheries target and catch fish both for direct human consumption (DHC) as well as for fishmeal and fish oil, and other products. We derived the fractions used for each for 1950–2010 by fishing country, and thus provide a factual foundation for discussions of the optimal use of fisheries resources. From 1950 to 2010, 27% (~20 million tonnes annually) of globally reconstructed marine fisheries landings were destined for uses other than DHC. Importantly, 90% of fish destined for uses other than DHC are food‐grade or prime food‐grade fish, while fish without a ready market for DHC make up a much smaller proportion. These findings have implications for how we are using fish to feed ourselves or, more appropriately, how we are not using fish to feed ourselves. 相似文献
154.
155.
Yong Li Katsutaro Yamamoto Tomonori Hiraishi Katsuaki Nashimoto Hiroyuki Yoshino 《Fisheries Science》2006,72(6):1147-1152
ABSTRACT: A field experiment was conducted in the Matsumae area of Hokkaido, Japan, during June and July 2002, to investigate the effects of different entrance designs on the catch efficiency of fish traps by fishing with commercial traps (entrance inclination angle [α] = 37°; funnel length of entrance [ L f ] = 22 cm) and experimental traps. The experimental traps were of the same size and similar design as commercial traps, with different entrance inclination angles (trap E1: α = 46°; E2: α = 27°; E3: α = 0°; all L f = 22 cm) or funnel lengths (E4: α = 37°, L f = 8 cm). In total, 2200 fish during 200 trap hauls were captured. The catch was significantly higher using both traps E2 and the commercial trap than with trap E3 ( P < 0.05), and the catch of trap E2 was higher than that of the commercial trap. There were no significant differences in mean fish body length or the frequency distributions of body length among trap types (E1, E2, E3 and commercial). The funnel length of the entrance also affected the catch of traps. Trap E4 had significantly higher catches than the commercial trap ( P = 0.04) when traps were deployed for a 1-day soak time. Fish body length frequency distributions did not differ between trap E4 and the commercial trap. The results showed that catch can be greatly affected by trap entrance designs. 相似文献
156.
南极磷虾生活在南极海域,资源量丰富,具有较高的应用价值.南极磷虾开发耗资巨大,在大规模商业性开发投入之前,做好相关产品与市场分析等基础工作十分必要.本文首先对南极磷虾产品的发展历程进行了分析,继而对南极磷虾产品的主要形式与发展前景进行了剖析,并对主要目标市场进行了定位研究.研究认为:南极磷虾粉和液态磷虾油是目前较为普遍的产品存在形式.其中,磷虾粉可作为蛋白质增强剂、增味剂和重要的氨基酸补充剂使用,可作为渗透调节之用,同时,可以作为矿物质来源、脂质来源、几丁质/几丁聚糖免疫增强剂、天然色素(类胡萝卜素)来源使用.磷虾粉的目标市场更倾向于水产饲料;磷虾油的目标市场主要倾向于营养保健和制药行业.相对于磷虾粉,磷虾油的市场价值更高. 相似文献
157.
本文报导了细鳞鱼(Braochymystax lenokP.)的形态构造、食性及其生态环境。调查了华北地区细鳞鱼分布变化情况,并阐明由于生态环境等因素的变化是引起该种在华北地区分布范围缩小的原因,同时提出保护细鳞鱼资资源的措施。 相似文献
158.
用酶联免疫吸附受体法检测鱼类生长激素的生物活性 总被引:13,自引:0,他引:13
根据激素一受体反应的原理,结合酶联免疫吸附测定法(ELISA)和放射受体测定法(RRA)的优点,应用我们纯化的A昌鱼生长激素(gcGH)和大鳞大马哈鱼生长激素(sGH)及其特异抗体,采用鱼类肝细胞膜受体制剂,首次建立了测定鱼类GH生物活性的酶联免疫吸附受体测定法(ELISA-RA)。此法检测草鱼GH的灵敏度达0.063 ̄0.125ug/ml,检测大马哈鱼GH与草鱼肝膜受体结合的灵敏度达0.25ug 相似文献
159.
选取初始体质量(73.81±9.02)g的雄性吉富罗非鱼(GIFFOreochromisniloticus),分别投喂含100%鱼油(A)、50%葵花籽油+50%鱼油(B)和100%葵花籽油(C)的饲料,每种饲料设置2个流速运动水平(0BL·s-1、1.5BL·s-1)(BL,体长),共6个试验组合(0A、1.5A、0B、1.5B、0C、1.5C),饲养42d后测定试验鱼生长和体成分变化。结果显示各组合吉富罗非鱼的成活率没有显著性差异(P〉0.05)。1.5B组合的特定生长率(4.96±0.02)%·d-1显著高于其他各组合(P〈0.05)。逆流运动后红肌和白肌蛋白质含量分别最高增加10.25%和7.74%(P〈0.05)。逆流运动对全鱼和肌肉多不饱和脂肪酸(PUFA)含量没有显著影响(P〉0.05),但饲料B组和c组鱼体红肌PUFA含量显著高于A组(P〈0.05),而B组和c组之间则没有显著差异(P〉0.05)。研究结果表明,葵花籽油替代鱼油对吉富罗非鱼的生长和体成分没有显著影响,而逆流运动能够显著提高肌肉蛋白质含量。 相似文献
160.
Immunostimulatory effects of dietary poly‐β‐hydroxybutyrate in European sea bass postlarvae 下载免费PDF全文
Andrea Franke Catriona Clemmesen Peter De Schryver Linsey Garcia‐Gonzalez Joanna J Miest Olivia Roth 《Aquaculture Research》2017,48(12):5707-5717
The stable production of high‐quality fry in marine aquaculture is still hampered by unpredictable mortality caused by infectious diseases during larval rearing. Consequently, the development of new biocontrol agents is crucial for a viable aquaculture industry. The bacterial energy storage compound poly‐β‐hydroxybutyrate (PHB) has been shown to exhibit beneficial properties on aquatic organisms such as enhanced survival, growth, disease resistance and a controlling effect on the gastrointestinal microbiota. However, the effect of PHB on the developing immune system of fish larvae has so far not been investigated. In this study, the effect of feeding PHB‐enriched Artemia nauplii on survival, growth and immune response in European sea bass (Dicentrarchus labrax) postlarvae was examined. Amorphous PHB was administered to 28‐day‐old sea bass postlarvae over a period of 10 days. The survival and growth performance were monitored, and the expression of 29 genes involved in immunity, growth, metabolism and stress‐response was measured. While the expression of the insulin‐like growth factor 1 (igf1), an indicator of relative growth, was upregulated in response to feeding PHB, the larval survival and growth performance remained unaffected. After 10 days of PHB treatment, the expression of the antimicrobial peptides dicentracin (dic) and hepcidin (hep) as well as mhc class IIa and mhc class IIb was elevated in the PHB fed postlarvae. This indicates that PHB is capable of stimulating the immune system of fish early life stages, which may be the cause of the increased resistance to diseases and robustness observed in previous studies. 相似文献