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1.
日粮水平对中华鳖稚鳖生长的影响   总被引:2,自引:0,他引:2  
于2001年12月购买当年繁殖的中华鳖(Trionyx sinensis)稚鳖(28.66-53.37g),在30℃水温下进行摄食-生长实验(实验时间为56d),设饥饿、1%、2%、4%和饱食5个日粮水平,研究了摄食水平对中华鳖稚鳖生长和转化效率的影响。方差分析表明:摄食水平对中华鳖稚鳖的特定生长率和转化效率均有显著影响。稚鳖的湿重、干重、蛋白质和能量的特定生长率均随摄食水平的增加呈二次曲线增加,摄食率(RL)-干物质特定生长率(SGRd)的关系模型可表示为:SGRa=-0.0832RL^2 1.0795RL-1.8779(n=25,r^2=0.906.F=105.46);当摄食率为6.97%、6.49%、6.08%和6.34%时,稚鳖湿重、干重、蛋白质和能量的特定生长率分别达到最大值。1%组的各项转化效率均显著低于2%和4%组,干重和能量转化效率显著低于饱食组;2%组的干重和能量转化效率显著高于4%和饱食组。  相似文献   

2.
Diets formulated to maximize performance of weanling pigs need to support the development of intestinal tissue, support intestinal colonization with beneficial, mainly lactic acid-producing bacteria, and support development of the intestinal and overall immune system. This objective is not likely to be achieved using one single strategy, but there is strong evidence that diets formulated with cereal grains other than corn, with a low concentration of crude protein and with the use of direct-fed microbials, will improve intestinal health and performance of weanling pigs. Further improvements may be observed if the grain part of the diet is fermented prior to feeding or if the diet is fed in a liquid form, but the need for specialized equipment limit the implementation of this strategy. Dietary supplements such as essential oils and nucleosides or nucleotides may also be useful, but more research is needed to verify the effects of these substances.  相似文献   

3.
心力衰竭是各种心血管疾病发展的终末阶段,而心室重构贯穿于心衰发生、发展的全过程,阻断心室重构是防治心衰不容忽视的一个重要环节。结缔组织生长因子是一种新发现的具有多种生物学功能的成纤维细胞生长因子,在病理情况下,能抑制心肌细胞外基质的降解,促进心肌细胞的凋亡,与动脉粥样硬化、器官纤维化、创伤后修复及组织瘢痕形成等密切相关。作为参与心力衰竭后心室重构的细胞因子,不仅能够成为评价心衰患者临床预后的指标,还有望成为抗纤维化治疗的新靶点。  相似文献   

4.
160 crossbred (Duroc × Landrace ×Yorkshire) gilts averaged 21.25 kg body weight were used to study the effects of dietary copper (II) sulfate (CuSO4) and copper proteinate (Cu-Pr) on growth performance, plasma Cu concentration, ceruloplasmin activity, and erythrocyte Cu/Zn-superoxide dismutase (SOD) activity. All pigs were allotted to four treatments and fed with basal diets supplemented with 0 (control), 250 mg /kg Cu as CuSO4, and 50 and 100 mg/kg Cu as Cu-Pr. Growth performance was determined based on two growth phase (phase 1: days 0 to 15, phase 2: days 15 to 30). After 30 days of the treatment, 16 pig blood samples (four per treatment) were collected for indexes of copper status determination. The experimental results showed that compared with control, pigs fed with 250 mg Cu/kg as CuSO4 and 100 mg Cu/kg as Cu-Pr had higher average daily gain and average daily feed intake in the whole growth phase (d 0 to 30). In addition, 250 mg Cu/kg as CuSO4 and 100 mg/kg Cu as Cu-Pr enhanced plasma ceruloplasmin activity (P < 0.05), and 100 mg/kg Cu as Cu-Pr increased erythrocyte Cu/Zn-SOD activity (P < 0.01) compared with the control. There was no obvious treatment response on plasma Cu concentration in the present study.  相似文献   

5.
Abstract: The activities of lipoyl dehydrogenase, aspartate transaminase, and alanine transaminase, and levels of lactate were estimated in cerebral cortex, cerebellum, and brainstem of rats intoxicated acutely with tetraethyl lead and chronically with lead acetate. A significant inhibition of lipoyl dehydrogenase was observed in both groups of animals, whereas transaminase activities were increased in inorganic lead toxicity. Oxidative decarboxylation and anaplerosis of pyruvate was assessed in brain slices using [l-14C]pyruvate. Pyruvate dehydrogenase activity was decreased in both organic and inorganic lead toxicity, whereas labelling of aspartate and alanine was increased in inorganic lead toxicity. In studies in vitro , lead acetate showed a more significant effect than tetraethyl lead. The higher anaerobic metabolism in inorganic lead toxicity, as evidenced by increased anaerobic lactate production by brain slices, could either be an adaptive mechanism or be due to the delayed maturation of brain in the developing rat. Such a mechanism does not occur in acute organic lead toxicity, as the compound brings about massive and rapid degenerative changes in brain, resulting in convulsive seizures and death of the animals.  相似文献   

6.
In this study, the speciation, vertical distribution and soil particle size fractions of lead in soil samples at a recreational firing range was determined. This study was performed to gain a better understanding of how lead shot breaks down at ranges. Both the chemical form of lead and the types of soil particles with which lead is associated are important for understanding not only the mobility and persistence, but also the human and ecological impact of lead at these ranges. Lead as shot gun pellets was found to be the dominant form of lead in soil samples. The highest levels were measured in surface samples located in the “fall zone” of the range. Results indicate shot to be relatively absent below surficial samples. Lead concentrations in soil decreased markedly across a 0–6″ depth profile. Lead carbonates were the dominant non-shot form of lead present at all depths. Water-soluble lead species made up a minor fraction of the non-shot lead present in the samples. Based on soil particle sizes measured, highest concentrations of lead were measured in soil particles passing a 0.075 mm sieve.  相似文献   

7.
目的探讨虫草培养基添加剂对Wistar大鼠生长发育和繁殖性能的影响。方法将虫草培养基添加在正常大鼠饲料中进行大鼠喂养试验,观察Wistar大鼠的生长发育和交配以及产仔情况进行统计分析。取大鼠卵巢和睾丸组织进行病理组织学观察。结果虫草培养基添加剂饲喂大鼠后,大鼠增重缓慢,雄性大鼠的饲料利用率有所增加,大鼠交配成功率和窝产仔数基本与对照组没有差异,大鼠卵巢和睾丸组织未受到器质性显微损伤。结论虫草培养基添加剂对大鼠生长发育和繁殖性能无特殊影响。  相似文献   

8.
本试验将40头21 d断奶的三元杂交猪随机分为4组,用4组不同日粮组成及营养水平的饲料(I:基础日粮+2%喷雾干燥血浆蛋白粉(SDPP);Ⅱ、Ⅲ和Ⅳ组分别在基础日粮中添加1%,2%和3%小肽营养素)饲养21 d后称重、测定血液生化指标并进行统计分析.结果表明:添加小肽营养素对断奶仔猪的生产性能无显著影响;各处理组的血清总蛋白、血糖和血清尿素差异不显著,2%小肽组的球蛋白、免疫球蛋白含量显著高于其它组;小肽产品可以部分等蛋白取代断奶仔猪日粮中的血浆蛋白粉.通过了解小肽营养素替代喷雾干燥血浆蛋白粉对21 d断奶仔猪的生产性能和血液生化指标的影响,为肽类产品在断奶仔猪日粮中的应用提供了依据.  相似文献   

9.
Chemical changes in central glutamate neurotransmission were assessed by measuring synaptic membrane receptor binding, the uptake and release by synaptosomes of glutamate in rats treated acutely with tetraethyl lead and chronically with lead acetate. The activity of Na+, K+-ATPase in synaptosomes was measured to correlate with the changes in uptake/release studies. The affinity of receptor binding and uptake systems was significantly reduced although the number of receptor sites and the capacity of uptake systems were increased. The activity of Na+, K+-ATPase was also found to be increased in synaptosomes. The changes were more marked in inorganic lead toxicity, and all three regions studied--cerebral cortex, cerebellum, and brainstem--showed significant alterations.  相似文献   

10.
Not only does tissue factor (TF) play a crucial role in hemostasis and thrombosis, but it is also involved in tumor progression and metastatic potency in some malignant tumors. We evaluated the clinical relevance of TF expression in melanocytic tumors and TF serum level in patients with malignant melanoma. TF expression in benign and malignant melanocytic lesions was examined by immunoperoxidase staining in 20 nevi, 41 primary, and 24 metastatic melanoma lesions. TF was detected in 94, 95, and 100% of these lesions, respectively. The staining pattern was membranous and cytoplasmic both in nevi and melanoma cells. This finding was confirmed by western blot analysis using cultured human melanocytes, nevi cells, and melanoma cell lines. TF was also expressed on blood vessels in benign and malignant melanocytic lesions. Expression of TF in primary melanoma lesions was not associated with any clinicopathological variables. In addition, the serum level of TF was elevated in 14% of patients with melanoma; however, it was not correlated with disease progression. These results suggest that TF was ubiquitously expressed in melanocytic cells and its expression was not correlated with disease progression and/or metastatic potency of melanoma cells.  相似文献   

11.
An experiment was performed to examine the effect of dietary copper supplementation on weight gain, neuropeptide Y (NPY) concentration and NPY mRNA expression level in the hypothalamus of pigs. Forty-five crossbred pigs were randomly assigned to three groups of 15 pigs, each comprising five replicates of 3 animals. Pigs were allocated to diets that contained 10 mg/kg (as a control), 125 and 250 mg/kg copper as CuSO4. Live weight gain and feed conversion efficiency was determined at the end of the experiment and five pigs, selected at random from each group, were slaughtered and the hypothalami collected for determination of NPY concentration and NPY mRNA expression level. The results showed that average daily gain (ADG) and average daily feed intake (ADFI) were higher and feed:gain (F:G) ratio was lower in pigs fed the diets with 125 and 250 mg/kg copper (P<0.05), respectively, than in pigs fed a diet with 10 mg/kg copper, but that there was no statistically significant difference in growth performance between animals of the 125 mg/kg and the 250 mg/kg copper groups. Furthermore, pigs fed diets with 125 and 250 mg/kg copper had higher NPY concentrations and NPY mRNA expression levels in their hypothalamus than control animals. The data indicated that 125 and 250 mg/kg copper gave similar responses in terms of weight gain, whilst high dietary copper could enhance NPY concentration and NPY mRNA expression level in the hypothalamus of pigs. High dietary copper appears to increase feed intake and promote weight gain by enhancing NPY concentration and NPY mRNA expression level in the hypothalamus of pigs.  相似文献   

12.
The present research evaluated differential effects of sodium selenite and nano-Se on growth performance, tissue Se distribution, and glutathione peroxidase (GSH-Px) activity of avian broiler. Broilers were randomly segregated into 12 groups so that three replicates were available for each of the three treatments (T-1, T-2, and T-3) and control groups. The control groups were fed basal diets without Se addition. T-1, T-2, and T-3 were fed with diets containing 0.2 mg kg−1 sodium selenite, 0.2 mg kg−1 nano-Se, and 0.5 mg kg−1 nano-Se, respectively. Compared with the control, Se supplementation remarkably improved daily weight gain and survival rate and decreased feed conversion ratio (P < 0.05). However, no significant difference was observed between T-1, T-2, and T-3. The tissue Se content was significantly higher (P < 0.05) in Se-supplemented groups than the control, and T-3 showed the highest. Furthermore, higher Se content was observed in liver, and there was a significant difference (P < 0.05) compared with that in muscle. As for serum and hepatic GSH-Px activities, Se supplementation remarkably improved GSH-Px activity (P < 0.05), and there was no significant difference (P > 0.05) between treatments (T-1, T-2, and T-3).  相似文献   

13.
为了解根际供氮对紫青菜(Brassica campestris ssp.chinensis var.communis)生长和营养品质的影响,用不同水平的NH_4NO_3处理,对紫青菜的生理特性和营养品质进行研究。结果表明,随着供氮水平的增加,紫青菜的鲜质量、干质量、根系活力和游离氨基酸含量均呈先上升后略下降趋势;硝酸还原酶(NR)活性、叶绿素含量、NO_3~–含量和可溶性蛋白质含量均呈上升趋势;DPPH·自由基清除率、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)同工酶和过氧化氢酶(CAT)同工酶活性等均提高;而花青素苷相对含量、可溶性糖含量、维生素C(Vc)含量、总酚含量和FRAP值均呈下降趋势。根际NH_4NO_3为75~300 mg L~(–1)时,紫青菜的鲜质量和干质量较低;NH_4NO_3达1200 mg L~(–1)时,其鲜质量和干质量又低于600 mg L~(–1)处理的,植株积累较多NO_3~–,导致营养品质下降,同时根际也积累NH4NO3。因此,600 mg L~(–1)的根际NH_4NO_3是适宜的氮水平,其鲜质量和干质量均最高、营养均衡、抗氧化能力强。  相似文献   

14.
目的在实验豚鼠饲养盒内增加梯形和管形两种不同的模具,进行环境丰富化模具对豚鼠生长及行为影响的研究。方法每组豚鼠饲养4周,每周称1次体重,记录体重变化趋势,并观察豚鼠行为变化。结果放入模具的豚鼠生长情况优越于对照组,管形模具优于其他实验组。结论增加环境丰富化模具有利于豚鼠生长,且管形模具更接近豚鼠自然洞穴状态,更加有利于豚鼠实现自然躲藏行为和良好的生长、生活。  相似文献   

15.
A growth trial with 38 weaners (castrated male pigs) was designed to compare the growth performance and carcass quality of pigs fed diets containing either soy bean meal or soy protein concentrate in a pair-feeding design. Soy bean meal (SBM) and soy protein concentrate (SPC) differed in isoflavone (daidzein plus genistein) content (782?μg/g in SBM and 125?μg/g in SPC, respectively). During the experiment, all pigs were fed four-phases-diets characterized by decreasing protein concentrations with increasing age (weaner I, weaner II, grower, finisher diets). Rations of control and experimental groups were isoenergetic, isonitrogenous, and isoaminogen. The weanling pigs with an initial live weight of 8.4?±?1.1?kg were allotted to flat deck boxes. During the growing/finishing period (days 70?–?170 of age), the pigs were housed in single boxes. Both, the weaning and the grower/finishing performances (daily body weight gain, feed intake, feed conversion ratio) were similar in both groups. No differences were found between the groups in carcass composition (percentages of cuts, tissues, and protein/fat), and meat quality of pigs. Moreover, the IGF-1R mRNA expression in longissimus muscle was not influenced by the kind of soy product. However, circulating levels of isoflavones were clearly different between pigs fed SBM (genistein 239?±?44; daidzein 162?±?42; equol 12?±?4?ng/ml plasma) and animals fed SPC (genistein 22?±?9 and daidzein 8?±?3, and equol 10?±?3?ng/ml plasma). The results confirm the expected differences in the bioavailability of soy isoflavones, yet, there were no significant differences in performance of pigs fed either soy bean meal or soy protein concentrate.  相似文献   

16.
为了解植物生长状态对环境羟基自由基水平的影响,研究了相同培养条件下不同生长状态的绿豆(Vigna radiata)幼苗对空气中的羟基自由基水平的影响。结果表明,正常生长的绿豆幼苗周围环境羟基自由基水平显著高于没有植物生长的环境,失活幼苗对周围环境羟基自由水平没有显著影响;渗透胁迫的绿豆幼苗对环境羟基自由基水平影响极显著,渗透胁迫程度不同其影响程度也有所不同;绿豆幼苗对环境羟基自由基水平的影响与其呼吸速率密切相关。这证明绿豆幼苗生长对环境羟基自由基水平有影响,且这种影响依赖于其生理代谢过程及生长状态。  相似文献   

17.
目的:研究蒙脱石散联合止泻保童颗粒对腹泻患儿血清C反应蛋白(CRP)及心肌酶谱水平的影响。方法:回顾性分析2012年7月至2013年6月在本院进行治疗的腹泻患儿,39例采取蒙脱石散治疗(对照组),39例采取蒙脱石散联合止泻保童颗粒治疗(观察组)。比较两组患儿有关症状改善时间和临床疗效,分析两组患儿治疗前后血清CRP及心肌酶谱水平。结果:治疗后,观察组总有效率显著高于对照组(P0.05),血清CRP、谷丙转氨酶(ALT)、乳酸脱氢酶(LDH)、肌酸激酶(CK)、谷草转氨酶(AST)、肌酸激酶同工酶(CK-MB)水平均显著低于对照组(P0.05),止泻时间、大便恢复至正常时间、退热时间显著短于对照组(P0.05)。结论:腹泻患儿经蒙脱石散联合止泻保童颗粒治疗较单用蒙脱石散能更有效降低患儿血清CRP水平,改善患儿的心肌酶谱水平,患儿的临床症状可快速恢复,临床疗效更好。  相似文献   

18.
不同饵料和水温对口虾蛄成活、生长及育肥性能的影响   总被引:1,自引:0,他引:1  
为比较不同饵料、水温对口虾蛄(Oratosquilla oratoria)在越冬期间生长育肥及性腺发育的影响,选用当年池塘养殖口虾蛄[初始体重(21.99±4.86)g,n=600]为研究对象,在养殖设施相同条件下,研究了在自然水温(7.7~13.6℃)和加温(17.1~20.9℃)条件下投喂去壳蛤蜊(Ruditapes philippinarum)和冰鲜杂鱼对口虾蛄的成活率、体长、体宽、体重、性腺指数、肌肉指数及可食率等7项指标的影响。实验共分常温蛤蜊、常温冰鲜杂鱼、加温蛤蜊和加温冰鲜杂鱼4个实验组,实验周期为90 d。结果显示:(1)加温可使口虾蛄成活率显著降低,温度是影响口虾蛄越冬成活的重要因素之一;(2)在整个实验过程中口虾蛄的体长、体宽和体重3项生物学指标均随实验天数的增加呈增长趋势,但各指标不同时间均不存在显著性差异(P 0.05);(3)常温条件比加温条件更有益于口虾蛄性腺指数的增加,其中以常温投喂去壳蛤蜊的效果最好,其性腺指数平均可达14.53%(♀)和7.69%(♂);(4)在整个实验过程中,口虾蛄的肌肉指数随实验进行总体呈上升趋势,除常温蛤蜊与加温蛤蜊实验组间的口虾蛄可食率存在显著性差异(P 0.05)外,其他各实验组两两之间均不存在显著性差异(P0.05);(5)不同饵料和水温的交互影响结果表明,温度是影响口虾蛄性腺指数的重要因素(P 0.01),饵料仅对雌性口虾蛄性腺指数产生显著性影响(P 0.01)。实验结果表明,相对于加温环境,常温环境基本能满足口虾蛄越冬期间的生长和育肥的需求,特别是在10~13℃的水温条件;与冰鲜杂鱼相比,摄食去壳蛤蜊更有利于口虾蛄的性腺发育积累。  相似文献   

19.
Selenium (Se) has been demonstrated in previous studies to inhibit mammary tumorigenesis in C3H mice infected with the murine mammary tumorvirus, MMTV. The antitumorigenic effects of Se in this animal model of breast cancer were subsequently shown to be counteracted by Se-antagonistic elements. Lead (Pb), for example, was found to abolish the anticarcinogenic effects of Se at 5 ppm in the drinking water. The present study was undertaken to explore the effects of Pb at just 0.5 ppm in the water, i.e., at a level comparable to the concentrations of Pb that have been measured in the tap water of older homes in some communities. Groups of 30 female virgin C3H/St mice infected with MMTV maintained on Torula yeast-based diets containing either 0.15 or 0.65 ppm of yeast-based organic Se and received either deionized water or water containing 0.5 ppm Pb as the acetate over their entire postweaning lifespan. In the control group on deionized water and the 0.15 ppm Se feed, the tumor incidence was 78.6%, which is normal for this strain. Increasing the Se content of the feed to 0.65 ppm lowered the tumor incidence to 30%, demonstrating the antitumorigenic effect of Se. In the experimental groups, the Pb-exposed mice on the 0.15 ppm Se feed developed signs of chronic Pb toxicity as evidenced by diminished weight gain that persisted up to the age of 10 months, during which period the animals remained tumor-free. Thereafter, weight gains ensued to near the values of the controls, and the tumors began to develop in rapid succession until the final tumor incidence of 73.7% was reached. In the group of mice on the 0.65 ppm Se feed, the toxic effects of Pb were diminished, as evidenced by the normal weight gains during the first 10 months but with concomitant physiological inactivation of Se, causing 82.6% of the mice to develop tumors, with the first tumor to appear at the age of 5 months, 7 months earlier than in the Pb-unexposed controls. In addition, tumor growth rates in this group were greatly accelerated and the survival of the tumor-bearing animals was significantly shortened. Direct evidence for the interactions of Pb with Se were obtained by determinations of the two elements in the livers, kidneys, and hair of tumor-free and tumor-bearing mice. However, the exposure of the mice to Pb in the water also altered the levels of Zn, Cu, Fe, and Cr in the organs and tissues, more so in tumor-bearing than tumor-free animals. The present study demonstrates the need to consider the interactions of Se with other trace elements in discussions of its mechanism of anticarcinogenic action.  相似文献   

20.
纤维素酶对生长育肥猪饲养效果的影响   总被引:2,自引:0,他引:2  
本试验选用32头67日龄皮大长白杂交生长育肥猪,随机分为两组,试验组日粮在对照组日粮基础上添加0.1%纤维素酶制剂,通过40天的实验结果表明对照组日增重为351.05克,试验组为405.94克,日增重提高15.64%,差异显著(P〈0.01),饲料报酬提高7.21%,经济效益明显增加。说明该纤维素酶制剂应用于饲喂生长猪是可行的。  相似文献   

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