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131.
饲料中添加虾青素对红罗非鱼各组织类胡萝卜素含量和沉积率的影响 总被引:4,自引:3,他引:1
通过在饲料中添加不同含量虾青素,测定粉白、红斑、黑斑3种体色红罗非鱼各组织(皮肤、鳍、肌肉、眼球、鳃)类胡萝卜素含量的变化,分析不同虾青素含量对红罗非鱼不同组织类胡萝卜素含量的影响,从而推断类胡萝卜素在不同组织间的表达和沉积方式。结果显示,虾青素添加量为400 mg/kg时,红罗非鱼皮肤、鳍、肌肉、眼球和鳃中的类胡萝卜素含量与对照组相比均明显提高,体色明显改善,其中黑斑红罗非鱼鳃部类胡萝卜素沉积比对照组有显著提高(P0.05)。而当虾青素添加量为800 mg/kg时,粉白红罗非鱼鳍上和鳃部及黑斑红罗非鱼鳃部类胡萝卜素沉积比对照组有显著提高(P0.05),但3种体色红罗非鱼一些组织器官类胡萝卜素含量相对对照组及虾青素添加量为400 mg/kg时有所下降,红罗非鱼体色变化不明显。虾青素含量对红罗非鱼各组织类胡萝卜素总含量有显著影响(P0.01);而红罗非鱼体色对类胡萝卜素总含量影响不显著(P0.05);虾青素和体色交互作用对类胡萝卜素含量有较显著影响(P0.05)。聚类分析表明,类胡萝卜素在红罗非鱼的鳍中沉积率最高,其次为鳃,再次为眼球,皮肤和肌肉沉积率最低。 相似文献
132.
不同给药方式下培氟沙星在鲤体内的药代动力学研究 总被引:1,自引:0,他引:1
在水温为18℃下,按10 mg/kg(体质量)对体质量为(200±30)g的福瑞鲤Cyprinus carpio单次肌肉注射和混饲口灌培氟沙星,于不同时间点采集鲤血浆、肌肉、肝胰脏、肾脏组织,经超高液相色谱法测定各组织中培氟沙星的浓度,并采用DAS 3.0药物代谢动力学软件的非房室模型统计矩方法分析药时数据。结果表明:混饲口灌给药和肌注给药后,培氟沙星的药时曲线下面积( AUC)分别为88.35、139.9 mg·h/L,达峰浓度( Cmax )分别为2.092、3.687 mg/L,达峰时间( Tmax )分别为4.0、0.5 h,消除半衰期( t1/2)分别为22.301、74.357 h,表观分布容积( Vd )分别为5.464、15.342 L/kg,总体清除率( CL )分别为0.170、0.143 L·kg/h。研究表明,肌肉注射给药较混饲口灌达峰时间短,达峰浓度高,半衰期长,生物利用度高。 相似文献
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136.
超高压对草鱼肌肉超微结构与质构特性的影响 总被引:3,自引:0,他引:3
研究了等静超高压对草鱼肌肉超微结构与质构特性的影响,并与猪肌肉用对照。结果表明:1.加压处理的草鱼肌肉,其超微结构中出现较明显的变化,如肌原纤维中A带和I带的细丝均被破坏,粗丝相互聚集,出现间隙,Z线变粗,不连续,H带和M线消失等,但肌原纤维的外形仍保持完整。2加压处理的草鱼肌肉,其外观无显著变化,色泽稍白,略有汁液流出,但质构特性与处理前无明显差别。 相似文献
137.
通过对围网渔船起网过程中所受外力的实测和分析,表明在绞收括纲阶段临近结束时,即底环集中串挂在船舷括纲吊柱处时的外力,最大可达7,140公斤。起网时外力对船作用最终表现为外力矩,其数值与网具的纲索或网衣相对于船的出水点位置以及各种捕捞、起吊设备的安装位置有关,也即与力的作用线方向和作用点有关。作者认为在围网渔船稳性核核中,仅校核起吊底环和绞收网衣时的倾侧力矩是不够的,应选取整个起网过程中最大起网力矩(绞纲阶段末尾的倾侧力矩)用于渔船稳性校核和摇摆计算。 相似文献
138.
The growth of two breeds of common carp, Cyprinus carpio L., was tested in ponds under the climatic conditions of South Bohemia. T?eboň scaly carp (TR) and Hungarian mirror carp (M2) were kept in both low and high stocking densities during the second growing season and then stocked together for communal testing during the third growing season. Before the communal testing, the mean initial weights of fish from low‐ and high‐density stocks differed significantly (374.1 vs. 227.7 g for the TR breed and 766.7 vs. 317.3 g for the M2 breed respectively, P<0.01). After communal testing, mean weights of fish from low‐ and high‐density stocks gained 761.8 vs. 543.8 g for the TR breed and 1339.7 vs. 706.7 g for the M2 breed respectively. These observed weights were also significantly different (P<0.01). However, the test of corrected weight gain, i.e. gain not related to the initial weight of fish, revealed insignificant differences (P>0.01) between the weight gains after correction, i.e. the effect of different initial weights was successfully eliminated. These results seem to confirm the applicability of this method for the assessment of growth of purebred common carp under the climatic conditions of Central European fish farms. 相似文献
139.
Cultured red porgy Pagrus pagrus (L.) males (n=6) were sampled every 2 weeks for milt, in order to monitor changes in sperm quality parameters during a whole spawning period. On 11 January 2001, 60% of the fish were spermiating, increasing to 100% in mid‐February and dropping to 30% by mid‐April. Sperm density showed a slight increasing trend, with mean values ranging between 8.6 and 23.7×109 spermatozoa mL?1. Sperm motility percentage exhibited a significant improvement during the spawning season (analysis of variance (anova ) P=0.0001). The duration of forward motility for the major part of the monitoring period ranged between 2 and 4 min. Red porgy spermatozoa maintained their viability for many days after whole storage of milt at 4°C. During the monitoring period there were significant changes in the mean duration of sperm survival after cold storage, ranging from 5 to 12 days. The total volume of expressible milt was maximal on 28 March, increasing from a mean value of 1.7 mL to 5.3 mL kg?1. Milt production of captive‐reared red porgy does not appear to be limiting, when compared with the volume of expressible milt produced by other cultured marine fishes. 相似文献
140.
In aquaculture, ozone is used as a disinfectant. In its production, extensive amounts of oxygen are formed resulting in hyperoxic conditions in culture units. Both ozone and hyperoxia have the potential to be toxic via pro‐oxidant mechanisms and to activate antioxidant defence systems in cultured species. To eliminate systemic effects, blood of rainbow trout, Oncorhynchus mykiss (Walbaum), was exposed in vitro for 5 min to ozone/hyperoxia or hyperoxia, and changes in antioxidant defences and lipid peroxidation were measured after exposure. Ozone exposure caused severe damage in red blood cells (rbc) detected as increased lipid peroxidation and oxidized glutathione (GSSG) levels in both plasma and rbc. Oxygen exposure alone increased intracellular lipid peroxidation and GSSG levels 10 min after exposure and was not evident in the plasma at any time. Ozone, but not oxygen exposure, decreased reduced glutathione (GSH) levels in plasma, and the changes were negatively correlated with increased lipid peroxidation in rbc, indicating that extracellular GSH has a dynamic role in the protection of rbc from direct oxidation by ozone. Both ozone and hyperoxic conditions increased superoxide dismutase (SOD) activity in rbc 3 and 6 h after exposure. In contrast, catalase activity was only increased 10 min after oxygen exposure, suggesting other catalase activation mechanisms rather than enzyme induction. The recovery of lipid peroxidation and GSSG levels in rbc after hyperoxia, but not ozone exposure, indicated a capacity to defend against hyperoxia‐produced oxidative damage, but an overwhelming of antioxidant defences by ozone in rainbow trout rbc in vitro. 相似文献