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排序方式: 共有174条查询结果,搜索用时 46 毫秒
81.
Yan Wang Ling-Jun Kong Dominique P. Bureau 《Aquaculture (Amsterdam, Netherlands)》2006,261(4):1307-1313
The effect of replacing fish meal with soybean meal (SBM) in practical feeds for cuneate drum was evaluated in an 8-week net pen trial. The cuneate drum fingerlings (initial body weight 29.8 ± 1.3 g fish− 1) were fed six isonitrogenous and isocaloric feeds containing 39% digestible protein and 16 MJ kg− 1 digestible energy. The control feed was formulated to contain 40% herring meal, whereas in the other five feeds SBM was included at 11.3, 22.5, 33.8, 45.0 and 56.3% to replace 20, 40, 60, 80 or 100% of the fish meal. There were no significant differences in feed intake between fish fed the control feed and feeds in which SBM replaced 20 to 80% of the fish meal, but fish fed the fish meal free feed had higher feed intake than the other treatments. Weight gain linearly declined with the decrease of fish meal level. Final body weight (FBW) of fish fed the feeds in which SBM replaced 20% of the fish meal did not significantly differ from fish fed the control feed. Replacing 40 to 100% of the fish meal resulted in lower FBW and nitrogen retention efficiency (NRE), and higher feed conversion ratio (FCR) than those of fish fed the control feed. Fish fed the feeds in which SBM replaced 60 to 100% of the fish meal had lower condition factor and hepatosomatic index than those of fish fed the control feed. No significant differences in carcass protein content was found among the treatments, but fish fed the feeds in which SBM replaced 60 to 100% of the fish meal had higher moisture and lower lipid content in carcass than those of fish fed the control feed. Results of the present study appear to indicate that cuneate drum has a limited ability to utilize SBM as a protein source in practical feeds. 相似文献
82.
Because of the high costs associated with feed inputs, as well as increased concern about waste production on fish farms, there is considerable interest in developing growout diets which are both cost effective and low polluting. In two 12‐week growth trials, the response of subadult red drum, Sciaenops ocellatus, fed either a diet of 440 or 360 g protein kg?1 diet (44% or 36%) with varying E:P ratios were tested. In the first experiment, five diets containing 440 g protein kg?1 diet and one diet containing 360 g protein kg?1 diet (reference) were offered to red drum (mean initial weight of 186 g). The five test diets contained 83, 103, 123, 143, and 163 g lipid kg?1 diet, resulting in E:P ratios ranging from 34.3 to 38.9 kJ g protein–1. In experiment 2, five diets providing 360 g protein kg?1 diet and one diet containing 440 g protein kg?1 diet (reference) were offered to red drum (mean initial weight of 145 g). Dietary lipid levels included 83, 123, and 163 g lipid kg?1 diet, and dietary carbohydrate was diluted with 10% and 20% non‐nutritive bulk filler in two of the diets to result in E:P ratios ranging from 34.5 to 46.7 kJ g protein–1. In experiment 1, no significant differences in mean final weight, mean weight gain, feed efficiency, protein conversion efficiency or hepatosomatic index were observed between the five test diets providing 440 g protein kg?1 diet. Intraperitoneal fat generally increased with increasing dietary lipid. The results of experiment 2 indicate that amongst the test diets with 360 g protein kg?1 diet, mean final weight, mean weight gain, feed efficiency, protein conversion efficiency and hepatosomatic index were not significantly different. Intraperitoneal fat significantly increased with increasing dietary lipid. In both experiments, fish offered diets with 440 g protein kg?1 diet produced significantly higher growth and FE values as compared to fish receiving diets containing 360 g protein kg?1 diet. This study indicated that subadult red drum are tolerant of shifts in E:P ratios and utilize a wide range of dietary lipid and carbohydrate without compromising growth. 相似文献
83.
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85.
《Journal Of Applied Aquaculture》2013,25(3-4):173-181
Abstract The replacement of fish meal with soybean meal in fish diets has met with varying degrees of success. Quite often, poor responses to high soybean meal diets are due to a reduced palatability of the diet when fish meal is removed. Recent work has demonstrated that poultry by-product meal can be used as a substitute for fish meal in practical diets for juvenile red drum (Sciaenops ocellatus), indicating it may have favorable palatability characteristics for this species. The present research was designed to evaluate the replacement of menhaden fish meal with solvent-extracted soybean meal in practical diets containing 20% poultry by-product meal and formulated to contain 44% protein and 10% lipid. Test diets were adjusted for phosphorus and methionine content to ensure that minimal dietary requirements were maintained. The response of red drum (mean initial weight 179 g) to diets containing fish meal ranging from 40 to 5% of the diet, as well as the response to a low fish meal diet supplemented with krill hydrolysate, were evaluated over a 14-week growth period. Final weights (percent gain) ranged from 588 g (237.8%) to 651 g (258.5%), with feed conversion efficiencies ranging from 62.1% to 69.9% and protein conversion efficiencies ranging from 27.8% to 30%. No significant differences (P > 0.05) were observed for diet intake, feed conversion efficiency, protein conversion efficiency, intraperitoneal fat ratio, or weight gain. Significant differences in protein intake and the hepatosomatic index were observed. The present findings suggest that fish meal can be reduced to 5% of the diet by replacing it with solvent-extracted soybean meal as well as methionine and phosphorus supplements. Although diets without poultry by-product meal were not tested, it is presumed that the poultry meal enhanced the palatability of the diets, allowing the replacement of fish meal with soybean meal. 相似文献
86.
Zafer Akpιnar Hüseyin Sevgili Talip Özgen Abdullah Demir Yιlmaz Emre 《Aquaculture Research》2012,43(3):421-429
This study was undertaken to determine the dietary protein requirement of shi drum (Umbrina cirrosa L.) with an initial weight of 86.3±0.4 g. The fish were fed five isoenergetic diets containing dietary protein levels ranging from 35% to 59% by 6% increments [the estimated digestible protein (DP) levels ranged between 29.6% and 52.8%], and the growth response over a 10‐week period was monitored. Each experimental diet was given to triplicate groups of fish. The final weight, weight gain and daily growth coefficient increased with the dietary protein level, reaching a plateau at the dietary level of 47% protein. The feed conversion ratio improved with increasing dietary protein level. The daily feed intake was significantly lower in fish fed 53% and 59% protein diets compared with those fed 35% protein diet. However, protein intake showed an increasing trend with increasing dietary protein and became significantly different between the 59% and the 35% protein diets. The protein efficiency ratio, protein retention and condition factor were not affected significantly by the dietary treatments. The final body composition was not influenced by the treatments. The recommended dietary protein percentage and DP/digestible energy (DE) ratio for juvenile shi drum diets are 51.4% (45.6% DP) and 28.5 g DP MJ DE?1 respectively. 相似文献
87.
Gillnets fished in North Carolina, USA, estuaries have high rates of bycatch relative to the target catch of southern flounder, Paralichthys lethostigma Jordan & Gilbert. This study tested whether rectangular‐mesh gillnets would maintain catch rates of southern flounder and reduce fish bycatch relative to conventional diamond‐mesh gillnets in two North Carolina estuaries. In the Neuse River estuary, catch rates of legal southern flounder were not different between the two mesh shapes, but the bycatch of red drum, Sciaenops ocellatus (Linnaeus) and other fish species was reduced with rectangular‐mesh net. In the Newport River estuary, southern flounder and red drum catches were reduced in rectangular‐mesh net, but the decrease was greater for red drum. Catches of sublegal southern flounder were reduced in the rectangular‐mesh net in both estuaries. Reduced catch rates of sublegal southern flounder and bycatch species suggest rectangular mesh may help manage stocks of estuarine fish species in areas where gillnets are used to target flatfishes. 相似文献
88.
89.
世界上275种石首鱼类中仅有极少数终生生活在淡水中,北美洲特有的淡水石首鱼(Aplodinotus grunniens)是其中一种,其形态学和内部解剖学特征研究对探讨石首鱼类的系统发育和进化具有重要价值。本研究较系统地对淡水石首鱼幼鱼的外部形态学可量可数性状进行测量,对内部主要器官结构及矢耳石特征进行解剖学观察。结果显示:除了吻端、颐部和峡部外,淡水石首鱼体被两种鳞片,头部两侧的鳃盖及眼睛周边覆盖小圆鳞,头后身体包括喉部均被栉鳞,且在头背交界处存在两种鳞片的过渡类型;侧线鳞从头后一直延伸至尾鳍的1/2处。腹鳍第一鳍条膜稍延长形成特有的鳍丝。黏液孔主要分布在颐部,为五孔型;具有犬牙状的颌齿和咽齿,所有齿尖均向口腔内部方向弯曲,上咽齿盘分为左右对称的2个咽齿盘,而下咽齿盘愈合为一体;消化道主要由口咽腔、较短的食道、卜形胃、具有2个弯转的肠道及肛门组成,在胃与肠交界处具有7个环状排列的指状幽门盲囊。矢耳石的形态特征与中国的黄唇鱼相似。基于外部形态学和内部解剖学特征,讨论分析了淡水石首鱼与中国石首鱼物种的亲缘关系。淡水石首鱼归属于低级底栖肉食性鱼类,这与其特定的生态习性和摄食特性等相符合。本研究旨在为中国淡水石首鱼人工驯养和紫黑翼蚌的规模化寄生繁育奠定基础,也为探讨石首鱼类在海淡水区域地理格局演化提供了基础资料。 相似文献
90.
Dietary requirements for leucine,isoleucine and valine (branched‐chain amino acids) by juvenile red drum Sciaenops ocellatus 下载免费PDF全文
The objective of this study was to determine the minimum dietary requirements of the branched‐chain amino acids (BCAAs: leucine [Leu], isoleucine [Ile] and valine [Val]) for juvenile red drum, Sciaenops ocellatus. This was accomplished by conducting three independent 49‐day feeding trials with juvenile red drum. Experimental diets were prepared by supplementing a basal diet containing 370 g/kg crude protein from red drum muscle and crystalline amino acids with incremental levels of Leu (9.0, 13.0, 17.0, 21.0, 25.0 and 29.0 g/kg of dry diet), Ile (5.0, 8.0, 11.0, 14.0, 17.0 and 20.0 g/kg of dry diet) and Val (6.8, 8.0, 9.2, 10.4, 11.6, 12.8 and 14.0 g/kg of dry diet). Fish were fed to apparent satiation twice daily in each trial, after which growth performance parameters were calculated and body composition and concentrations of BCAAs in plasma were analysed. Incremental levels of dietary Leu, Ile and Val significantly affected weight gain, feed efficiency and protein retention. Analyses of the weight gain data using a broken‐line regression model estimated the minimum Leu, Ile and Val requirements for maximum growth of juvenile red drum to be 15.7 ± 1.7 g/kg (±95% confidence interval), 11.1 ± 2.3 g/kg and 12.4 ± 0.6 g/kg of dry diet, respectively. 相似文献