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21.
本研究旨在探讨鱼油对高脂日粮饲喂小鼠发情周期和机体代谢产热的影响。试验选用36只4周龄C57BL/6 J雌性小鼠,随机分成3组(n=12):对照组、高脂组和高脂+鱼油组。对照组饲喂标准啮齿动物饲料(AIN-93G),高脂组和高脂+鱼油组分别饲喂高脂日粮(脂肪提供60%能量)和添加5%鱼油(等能替代猪油)的高脂日粮。试验期间,对小鼠体组成(12周龄)、整体代谢(16周龄)、褐色脂肪温度(18周龄)、体核温度(直肠温度,18周龄)和发情周期(20周龄)等进行检测。试验结束后,眼球采血分离血清,检测促卵泡激素(follicle-stimulating hormone,FSH)和雌二醇(estradiol,E2)的水平。此外,采集皮下脂肪、腹部脂肪和肩胛间褐色脂肪,称重并使用Western blot检测脂肪组织中产热相关基因的蛋白表达(UCP1、Cyto C),使用实时荧光定量PCR检测褐色脂肪组织中产热基因的mRNA表达(UCP1, PRDM16,PGC1α,Cidea,Elovl3)。结果显示,与对照组相比,高脂日粮显著增加了小鼠的体脂含量(12周龄)及皮下和腹部脂肪的沉积量(21周龄)(P<0.05),而添加鱼油显著降低了高脂饮食引起的体脂含量增加(P<0.05)。另外,高脂日粮导致小鼠的发情周期紊乱,伴随着周期延长、发情期缩短,以及血清中FSH和E2的水平降低(P<0.05),而添加鱼油可缓解高脂日粮导致的小鼠发情周期紊乱,提高血清中FSH和E2的水平(P<0.05)。同时,添加鱼油可增加高脂饲喂小鼠肩胛间褐色脂肪(interscapular brown adipose tissue,iBAT)和腹股沟白色脂肪(inguinal white adipose tissue,iWAT)中产热相关基因的表达(P<0.05),进而促进iBAT激活/产热和iWAT褐色化。结果提示,日粮鱼油可缓解高脂日粮导致的发情周期紊乱,可能与BAT激活和WAT褐色化造成的机体代谢产热增强有关。  相似文献   
22.
In the present study, the location, histology and number of corpuscles of Stannius (Sc), which are endocrine glands associated with the kidneys of teleost fish, were investigated for the first time in Lake Van fish (Alburnus tarichi), an anadromous and endemic inhabiting Turkey's Lake Van Basin. The Sc, which were ovoid or spheroid and white or cream in colour, were found to vary in number between three and five among the examined fish. The glands were located in the caudal part of the kidney, and either partially or completely embedded, and found to be present on both the ventral and dorsal surface of either side of the caudal part of the kidney. The Sc were surrounded by a connective tissue capsule that penetrated and divided the gland into incomplete lobules. Two types of cells were determined in the parenchyma of the gland. Type-I cells were predominant throughout the parenchyma and larger than the second (type-II). In the type-I cells, the cytoplasm was observed as weakly or moderately eosinophilic with haematoxylin and eosin staining and weakly or moderately acidophilic with Mallory's triple staining. In the type-I cells, the cytoplasm exhibited weak to moderate periodic acid-Schiff staining and slight or uniform staining with aldehyde fuchsin. The type-II cells were round, had a darkly stained spherical nucleus and were dispersed among the type-I cells. They displayed no cytoplasmic staining with the abovementioned stains.  相似文献   
23.
This study sought to determine whether fermentation could increase apparent ileal digestibility (AID) of dry matter (DM), nitrogen (N), energy (E) and amino acids (AA) in fermented soybean meal (FSBM) greater than that of soybean meal (SBM) in weaned pigs. Four weaned pigs (10.00 ± 0.30 kg) were surgically equipped with T‐cannulas and randomly followed a 4 × 4 Latin square design of treatments (SBM, FSBM, fish meal and spray‐dried plasma protein). Overall, the fermentation process was able to reduce the amount of anti‐nutritional factors (ANF), including trypsin inhibitors, raffinose and stachyose, in the FSBM diet, which were significantly reduced by 39.4, 92.2, and 92.9%, respectively, as compared to the SBM diet. As a consequence of ANF reduction in FSBM, the AID of DM, N and E as well as AA was significantly greater with FSBM than SBM. Taken all together, the fermentation process improved the nutritional quality of SBM, due to ANF reduction, leading to improvement of digestibility of AA. As such, FSBM can be potentially used as a specialized feed ingredient, especially for young animal diets in an attempt to reduce diet costs.  相似文献   
24.
The aim of this experiment was to compare the level of fish female stress during induced reproduction with pituitary extract by two different methods, natural and semiextruded. The reproductive efficiency was 62.5% in the seminatural treatment and 100% in the extruded. Obtained egg volume was 5200 ml and 4000 ml, for seminatural and extruded treatments respectively. The mean number of eggs was 46.7 for the seminatural and 52.0 and for the extruded treatment. The percentage of viable eggs was, respectively, 87.2% and 8.17% for the natural treatment and extruded semimethods. Blood samples were collected to quantify cortisol and glucose levels, as well as red cell series and lymphocyte count. Fishes submitted to induction procedures showed elevated cortisol and glucose levels, compared to the control animals. The results for haematocrit, haemoglobin concentration and red blood cell count showed no significant differences among groups. Significant differences found in the number of lymphocytes and monocytes suggest the general adaptation syndrome. Our results suggest the reproductive induction process with extrusion of gametes as a more stressful method than seminatural reproduction process.  相似文献   
25.
中国生物质能资源的贮量较为丰富,在中国总的能源消耗中,尤其在中国农村能源消耗中,所占的比重较大。为了合理和有效地开发生物质能资源,中国积极开发沼气、省柴灶和气化等能源技术。将来,秸秆气化气将作为一种洁净的能源被广泛采用。在黑龙江省的某些地区,秸秆气化养鱼温室技术将成为一种极具潜力的生物能利用方式,并会取得明显的能源、环境和经济效益。  相似文献   
26.
微分方程的平衡点可分为稳定和不稳定两种。当轻轻扰动平衡点时,系统状态就会剧烈变化。若新的状态决不会回到原平衡点,此点就是不稳定的;相反,如果一个系统在稳定平衡点附近受到干扰,它总是企图回到平衡点,那么此点就是稳定的。用这一数学工具可以解决诸如渔场鱼量等一系列实际问题。  相似文献   
27.
选择了4种家鱼作指示生物,用紫外分光光度法测定其白肌中RNA和DNA的含量。结果表明:同种鱼,污染区的RNA含量显著低于对照区,白鲢和鳊鱼白肌中RNA/DNA低于对照区;不同种的鱼,污染区鱼肌核酸比对照区下降的程度有鳊鱼>白鲢>鲫鱼和鲤鱼的趋势。鱼肌核酸下降同水体重金属污染有一定联系,RNA是比RNA/DNA更合适的指标,鳊鱼和白鲢是比鲫鱼和鲤鱼更敏感的指示生物。  相似文献   
28.
依据1992年和1993年4-5月收集的标本,分析保安湖乌鳢渔获体系结构和生长特征。年龄由Ⅰ-Ⅶ龄构成,Ⅰ-Ⅺ龄分别占渔获总尾数的12.37%,24.74%、41.24%和17.53%。Ⅴ-Ⅶ龄极少公占4.12%。优势体长为31-42cm;优势体重为350-950g。体长与体重关系为W=0.007991L^3.1602。VonBertalanffty生长方程为Lt=77.3(1-e^-0.1988  相似文献   
29.
杨贤  娄永江  严小军 《核农学报》2016,(11):2180-2188
为了去除鱼粉加工中产生的大量恶臭气体,利用DBD低温等离子体技术对硫化氢和三甲胺进行去除,并在单因素试验的基础上,采用Box-Behnken设计方法,考察了电压、放电频率、处理时间、初始浓度及其交互作用对硫化氢和三甲胺去除率的影响。结果表明,响应面法优化所得的最佳工艺条件为:电压10.6k V,放电频率8.91KHz,处理时间0.26s,硫化氢初始浓度0.76mg·m-3,三甲胺初始浓度为19.8mg·m-3。此条件下硫化氢和三甲胺的去除率均可达100%,能耗为1.77×10-2KW·h·m-3;同时,验证试验结果与模型预测值吻合。本研究为DBD技术在鱼粉厂去除恶臭气体中的应用奠定了基础。  相似文献   
30.
The dynamic behavior of a fish cage collar in waves was investigated using a numerical model based on the finite element method. The floating collar and mooring system were divided into a series of line segments modeled by straight massless model segments with a node at each end. To verify the validity of the numerical model, research data from other authors were cited and compared with the simulated results, the comparison of results showed a good agreement. The numerical model was then applied to a dynamic simulation of a floating cage collar in waves to analyze its elastic deformation and mooring line tension. The simulated results indicated that the greatest deformation of the collar taken place in the position of the mooring line connection point when incident waves were in the same direction. An increase in the length of mooring line would help to decrease the mooring line tension of the collar. Furthermore, the effects of collar dimension, including collar circumference, pipe diameter in cross-section, and pipe thickness, on the dynamic behavior of the floating collar were discussed. The results of this study provided a better understanding of the dynamic behavior of the fish cage collar.  相似文献   
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