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1.
豪猪常见疾病的综合防治技术研究   总被引:1,自引:0,他引:1  
通过探讨豪猪疾病发生的原因,介绍豪猪疾病诊断的方法、治疗的药物及其给药的方法、预防措施和防治的注意事项.详细论述了豪猪急性肺炎、肠炎、寄生虫病和外伤等常见疾病的综合防治技术.参9.  相似文献   

2.
应用体外胃肠模拟法研究土壤中多氯联苯的生物有效性   总被引:2,自引:0,他引:2  
徐瑾  陈广春  何欢  杨绍贵  孙成 《环境化学》2011,30(5):908-912
采用体外胃肠模拟法,研究了土壤中多氯联苯的生物有效性.研究结果表明,PCBs在模拟胃液中的生物有效性为3.36%-12.48%,肠液中的生物有效性为34.62%-58.90%.胃肠液的pH值、消化时间及液固比均会影响其生物有效性:pH在中性时的生物有效性显著高于酸性条件下,消化时间的延长和液固比的增加均会使生物有效性增...  相似文献   

3.
在北京市郊区一家中等规模养鸡场采集了不同品种和不同生长阶段的饲养鸡的肌肉和内脏样品,并同步采集了鸡蛋、饲料、粪便和大气样品,测定了其中苯并[a]芘的浓度,据此分析了苯并[a]芘在饲养鸡体内的积累、排泄和代谢的动态过程.结果显示,饲养鸡体内各组织苯并[a]芘的湿重浓度在0.024~0.15ng·g-1之间,肌肉中的浓度显著低于其它组织;饲料和粪便中的浓度显著高于体内各组织浓度.饲养鸡体内摄入的苯并[a]芘约60%在体内代谢,约三分之一直接排泄进入粪便,仅有少量残留在体内如表皮、肌肉和其他器官中.肌肉、肝脏和胃中苯并[a]芘浓度和总累积量的动态变化规律不尽相同.北京居民摄食类似鸡肉导致的对苯并[a]芘的暴露量较春、秋、冬季呼吸暴露量低两个量级,与夏季呼吸暴露量相当.  相似文献   

4.
重金属污染已成为水产品质量安全存在的主要问题之一.本研究通过测定湘江干流铜锈环棱螺肉中重金属(Cu、Zn、Cr、Cd、Pb)含量,并基于荷兰RIVM(the Dutch National Institute for Public Health and the Environment)体外消化模型模拟口腔、胃及肠道消化,计算螺肉中Cu、Zn、Cr、Cd、Pb的生物可给性,评估其食用健康风险.结果表明,螺肉中Cu、Zn、Cr、Cd、Pb的含量范围分别为35.68—116.96、202.51—323.20、4.41—95.93、0.29—16.08、0.12—17.35 mg·kg-1,且大多高于水产品重金属限量标准.螺肉中不同重金属的生物可给性差异较大,Zn、Cd和Pb在胃阶段的生物可给性高于口腔和肠阶段,Cu和Cr在肠阶段的生物可给性高于口腔和胃阶段.基于生物可给性的食用健康风险显示,螺肉中5种重金属的目标危害系数(THQ)和综合危害系数(HI)均小于1,不存在非致癌健康风险;但其综合致癌风险指数(TCR)均大于1×10-4,存在致癌风险. C...  相似文献   

5.
大熊猫是具有植食性转化阶段的特殊的食肉动物,但本身对纤维素的消化能力极低,主要依赖于肠道微生物的作用;处于食物转化阶段的大熊猫幼仔是敏感而脆弱的,对纤维素的适应消化能力也是保证其存活的关键.通过分析食物转化期大熊猫幼仔粪便中纤维素酶活性和肠道细菌多样性的变化,探讨大熊猫幼仔食物转化阶段肠道细菌性质和纤维素酶活性的相关性,以期为优化食物转化期大熊猫的饲养技术提供一定的理论指导.结果显示,大熊猫幼仔食物转化阶段纤维素酶活性变化较大,特别是增加竹子的摄入量后,大熊猫个体纤维素酶活性普遍显著增加.大熊猫肠道细菌的结构和数量在食物转化阶段也存在较大变化,且与幼仔消化纤维素密切相关,如Lactobacillus、Romboutsia等典型的肉食动物肠道菌的丰度在大熊猫幼仔肠道中数量减少,而纤维素降解菌属Cellulosiyticum的丰度明显增加,特别是大熊猫肠道优势菌属Streptococcus也表现出与其纤维素消化的密切联系.总体而言,食物转化阶段的大熊猫幼仔对纤维素有一定的适应性消化能力,其和肠道细菌菌群的演变有较大的相关性.(图3表6参30)  相似文献   

6.
为了解微囊藻毒索在鲋鱼Carassius auratus L.体内生物富集作用,用LC/MS监测不同时间的鲋鱼肝脏、肌肉,以及饲养用水中痕量的微囊藻毒素.结果显示,肌肉组织中MC-RR和MC-LR的含量在18 d时达到峰值,分别为7.87 ng·g~(-1)和2.18 ng·g~(-1);而肝脏组织中MC-RR和MC-LR的含量在鲋鱼暴露9天时达到最高值,分别为25.30 ng·g~(-1)和33.27ng·g~(-1).研究结果支持肝脏组织是MCs的主要靶向器官,并且表明肝脏组织对MC-LR的富集量远大于MC-RR,而肌肉组织更易于积累MC-RR.文章还研究了鲋鱼体内的抗氧化酶(SOD、CAT、GST、GR酶)的活性变化,对MCs介导的氧化胁迫进行了评估.通过分别测定暴露不同时间点(3、9、18 d)肝脏和肌肉组织中的抗氧化酶的活性,发现它们的活性与组织中MCs的含量基本呈正相关,可能对MCs介导的氧化胁迫有缓解作用.以上表明,MCs能在鱼体内积累,抗氧化系统虽可缓解,但不能完全降解.因此食用被MCs污染的鱼类存在潜在的食品安全风险.  相似文献   

7.
重庆主城餐厨垃圾理化性质及产甲烷潜能分析   总被引:3,自引:0,他引:3  
何琴  李蕾  何清明  彭绪亚 《环境化学》2014,(12):2191-2197
以重庆市主城区的餐厨垃圾为研究对象,调查分析其组成成分及粒径、含水率、挥发性固体(VS)含量等理化性质,并通过半连续式单相厌氧消化试验,进一步研究餐厨垃圾在中温条件下37±2℃的产甲烷性能.结果表明,重庆市主城区餐厨垃圾的主要成分为食物残渣、厨余废物等易消化物质,并具有含水率、含油率和VS含量较高等特性;半连续式厌氧消化试验所得实际产甲烷潜能为0.363—0.713 L CH4·g-1VS,占理论产甲烷潜能的45.77%—89.93%,稳定运行时VS去除率达到88.87%—93.85%.中温厌氧消化技术能有效地处理重庆市餐厨垃圾并同时从中高效地回收清洁能源沼气.  相似文献   

8.
以热水解后高含固污泥及其脱水后固、液分离产物为对象进行厌氧消化试验,通过生物化学甲烷势(BMP)及脱水性能测定,研究其产气量、有机物分布、污泥脱水性能及生物质能转化特性,评估高含固污泥热水解-脱水-脱水液厌氧消化工艺的可行性.结果表明,经热水解预处理的高含固污泥进行厌氧消化后,其毛细吸收时间(CST)及脱水泥饼含水率由247.5±0.9 s和71.1%±1.3%上升至568.0±1.6 s和80.7%±1.0%,即厌氧消化会导致热水解后污泥脱水性能下降.污泥中74.0%的有机物在水热预处理之后被转移至液相,是厌氧消化所产沼气的主要来源.物质能量衡算结果表明,高含固污泥采用热水解-脱水-脱水液厌氧消化工艺可以有效地将消化装置容积大大减少;沼气燃烧所产能量实现该工艺能量自给自足.  相似文献   

9.
体外消化过程可能导致土壤中憎水有机污染物提取量增加.论文采用3种有机质含量不同的土壤进行体外消化实验,目的在于验证如下假设:土壤中部分锁定残留芘可以在人体消化系统中释放出来,若不考虑这部分贡献,常规提取方式获得的土壤污染浓度可能低估污染土壤口摄风险.研究结果证实:经体外消化的土壤的总芘提取量显著高于未经消化样品,其差别与土壤有机质含量有关.消化液中的胆汁盐是造成锁定残留芘释放的关键成份.在特定范围(2~20mg·mL-1)内,提取效率不受胆汁盐浓度影响.胆汁盐作用下锁定残留芘的释放为一次动力学过程.  相似文献   

10.
土壤中六六六在消化道中生物可给性的体外测定   总被引:3,自引:2,他引:1  
采用体外消化实验模拟了4种有机质含量不同的土壤中六六六在胃和小肠中的释放,重点验证了消化释放出来的六六六在固态消化残渣上的吸着现象以及该现象对测定消化率的影响的研究假设.结果表明,固相吸着对测定消化率有非常显著的影响,这在有机质含量偏高的土壤中尤其明显.吸着影响可以用不同液固比实验设计配合非线性拟合方法加以校正.对有机碳含量分别为0.63%、1.08%、1.60%和2.87%的4种土壤,未经校正的总六六六消化率的均值与标准差分别为(16.7±2.8)%、(11.6±2.0)%、6.9%和(26.4±1.3)%,校正后则分别达到16.7%、16.5%、16.5%和59.7%.显然,除有机质含量很低的样品,未经校正的测定结果显著低估了消化道吸收风险.  相似文献   

11.
豪猪的发情观察及其鉴定方法初探   总被引:2,自引:0,他引:2  
1999年3月至2001年12月在湖南省衡东县特种经济动物研究所豪猪养殖场采用外生殖器观察、阴道分泌物涂片镜检、行为表现观察和放对试情等方法,对雌雄豪猪进行发情观察与鉴定.结果表明:豪猪的发情期有三个阶段,即发情前期,发情旺期和发情后期,其中发情旺期是豪猪的最佳配种时期.此期雌豪猪阴门表现出明显肿胀,呈现圆形,触摸有弹性,呈粉红色,阴道分泌物涂片镜检可见有核细胞和无核细胞;放对试情雌豪猪主动接近雄豪猪,发生交配行为.  相似文献   

12.
环境中的镉污染对动植物及人类都带来了极大的危害。目前,多数镉毒理研究关注其无机状态,而来源于稻米的有机态镉的毒害作用报道较少。为评估稻米来源镉对生长期猪的毒性作用,选用初始体重为30 kg左右的健康生长猪28头,随机分为体重无明显差异的2组,即对照组与稻米来源镉组(试验组),研究稻米来源镉对生长期猪(生长及育肥全阶段)的生长特性及不同脏器组织镉蓄积的影响。结果表明,在生长及育肥阶段,试验组与对照组相比:1)生长特性无显著差异(P0.05);2)育肥期组织游离氨基酸含量,除肌肉中的赖氨酸显著降低外(P0.05),血浆、肝脏、肾脏及肌肉中其他游离氨基酸水平均无显著差异(P0.05);3)心脏、肝脏、脾脏、肾脏、肺脏、胃、小肠、大肠、骨骼中镉蓄积量显著增高(P0.05),而肌肉、血液中无显著差异(P0.05),脂肪、皮中未检出镉。日粮使用大比例镉超标稻米后镉在各脏器和组织中的蓄积规律为肾脏肝脏小肠脾肺大肠胃血液骨头心腿肌背肌脂肪、皮。由此可见,镉超标稻米对生长期猪的生长特性未产生显著的影响,稻米来源镉主要蓄积于肝脏和肾脏,而主流食用组织肌肉和血液中镉的蓄积量较少。  相似文献   

13.
The study of how and why marine animals distribute themselves at sea has important conservation and management implications of the species and their habitats. We characterize the oceanographic and biological landscapes of the marine areas used by breeding Southern Giant Petrels (Macronectes giganteus) at Patagonian colonies and explore inter-sexual and inter-colony differences. The at-sea movements of 16 adults (7 males and 9 females) were studied by means of satellite telemetry techniques during 1999, 2000, 2002, and 2004 breeding seasons. Southern Giant Petrels utilized an oceanographic scenario characterized by high productivity, warm sea surface temperature, and shallow waters. The biological landscape was characterized by a high availability of squid and carrion nearby colonies. Females spent more time in the shelf break and exploited deeper waters than males. In contrast, males spent more time in coastal areas and they showed a higher spatial overlap with areas of high squid density than females. Such a prosperous foraging scenario for both sexes may play a key role in the growth of the breeding population of Southern Giant Petrel Patagonian colonies.  相似文献   

14.
A key challenge in ecology is to find ways to obtain complete and accurate information about the diets of animals. To respond to this challenge in seabirds, traditional methods (usually stomach content analysis or observations of prey at nests) have been supplemented with indirect methods or molecular trophic markers. These techniques have the potential to extend the period of investigation outside the few short months of breeding and avoid biases. Here, we use an analysis of fatty acids (FAs) and fatty alcohols (FALs) from blood, adipose tissue and stomach oil to investigate how the diets of male and female common guillemots (Uria aalge), black-legged kittiwakes (Rissa tridactyla) and northern fulmars (Fulmarus glacialis) differed through the sampling period (prelaying and breeding season) and by sex. Diets of both sexes of all three species generally varied across the season, but sex differences were apparent only in fulmars during prelaying. Our study shows that FA/FAL analysis can provide significant insights into diets of seabirds, in particular periods of the annual cycle which are not readily studied using traditional methods.  相似文献   

15.
The diet of white-chinned petrels Procellaria aequinoctialis breeding at the Crozet Archipelago (southern Indian Ocean) was studied using two complementary methods: lipid analysis of stomach oils as trophic markers together with the conventional dietary approach (i.e., stomach content analysis). Objectives were (1) to investigate the adult diet when they feed for themselves by analyzing stomach oil lipids, and (2) to compare the lipid signature of chick and adult oils. Stomach oils mainly consisted of triacylglycerols (TAG), diacylglycerol-ethers (DAGE) and wax esters (WE) (66, 14 and 11%, respectively). The dietary origin of TAG and WE was evaluated by linear discriminant analyses with fatty acid and fatty alcohol fractions. Analyses evidenced that stomach oils did not originate from Antarctic krill, but instead from myctophid fish, thus demonstrating the importance of mesopelagic fish in the nutrition of adult petrels. This result was consistent with the identification of digested remains of myctophids recovered from adult stomach contents after long foraging trips. Large amounts of a rare lipid class, DAGE (up to 76% of total lipids), were identified in two stomach oils, together with fresh remains of the squid Gonatus antarcticus (99% by mass), suggesting that DAGE could have the potential to be trophic markers of cephalopods. Moreover, six oils probably originated from Patagonian toothfish, thus confirming strong interactions between white-chinned petrels and fisheries. Comparison between chick and adult stomach oils indicated no major differences in their biochemical composition suggesting an identical dietary origin of oils, mainly myctophids. Both adult and chick oils can therefore be used to determine the feeding ecology of adult birds when they feed far away from their breeding grounds. Finally, food analysis of chick samples and adult samples collected after short and long trips indicated different foraging grounds during the two kinds of trips, and also between long trips performed in subtropical and Antarctic waters.  相似文献   

16.
Increasing environmental pollution in the tropics is creating a breeding ground for mosquitoes, leading to increasingly frequent use of insecticides to combat home infestation of mosquitoes, the vector of malarial parasites. Household members are therefore more prone to aerosol exposure and subsequent health effects. We assessed the hepatotoxic and clastogenic effects in rats exposed to different levels of aerosols of one of the insecticides most commonly in used in Nigeria. There were significant (p?2 in the groups of rats exposed to the aerosols when compared with the control group. In addition, rats exposed to the insecticide aerosols have elevated activities of serum enzymes: γ-glutamyl transferase, aspartate amino transferase and alanine amino transferase, as well as number of micronuclei scored in the bone marrow, at levels that are significantly (p?相似文献   

17.
The biology of Octopus vulgaris Cuvier inhabiting subtropical littoral reefs off the east coast of South Africa was investigated. Analyses of stomach contents and lair middens revealed that the mussel Perna perna was the dominant food organism. Growth rate of captive individuals was higher than has previously been recorded but food conversion was lower. Females became sexually mature at 900 g which is estimated to be attained in 3.6 months. Males became sexually mature at 400 g, which is estimated to be attained after 3 months. Results indicate that females live for 9–12 months and have the potential to reach 4 000 g in 240 d while males live for about 12–15 months and have the potential to achieve 4 000 g in 290 d. Mating and breeding occurred throughout the year although evidence for the seasonal migration of females is presented and discussed in relation to breeding and feeding behaviour.  相似文献   

18.
为了探讨体内亚硫酸氧化酶的分布特点及随年龄的变化规律,以Wistar大鼠为实验材料,研究了不同月龄大鼠脏器中的亚硫酸氧化酶活性.以细胞色素C为电子受体,应用分光光度法测定了不同月龄(1、4、10个月)大鼠肝、肾、肺、脾、脑、胃及胸主动脉中亚硫酸氧化酶的活性.结果表明:1)亚硫酸氧化酶在大鼠全身主要脏器中普遍存在,且在不同脏器中该酶的活性不同,从强到弱的顺序基本表现为:肝、肾>胃>脑>胸主动脉血管>肺>脾;2)肝、肾、血管组织中亚硫酸氧化酶活性与大鼠年龄相关,肝脏亚硫酸氧化酶活性随年龄的增加而增加(Spearman,r=0.674,p<0.001),而肾脏和胸主动脉血管该酶活性随年龄的增加而减小(Spearman,r=-0.756,p<0.001;r=-0.629;p<0.05),其余脏器未见明显变化;3)亚硫酸氧化酶活性降低可能是一种机体衰老的生化标志物.  相似文献   

19.
The effect of meal size (shrimp Crangon crangon) [0.83–18.82% dry body weight (Dw)] on specific dynamic action (SDA) was assessed in cuttlefish Sepia officinalis (1.03–6.25 g Dw) held at 15 and 20°C. Cuttlefish <2 g significantly expended less energy in feeding and digesting their meal than cuttlefish >2 g when given the same quantity of food. Handling, eating and digesting a shrimp meal was temperature dependent with cuttlefish processing and digesting a similar sized shrimp meal faster at 20°C than at 15°C. The proportional increase in oxygen consumption (2.07 ± 0.02) was not correlated with feeding rate (FR) and was independent of temperature and cuttlefish size. The SDA peak was not correlated with FRs, and increased as cuttlefish size and temperature increased. The mean SDA coefficient was 0.87 ± 0.07% of the ingested energy; one of the lowest SDA values recorded amongst vertebrates and invertebrates. Daily energy requirements (KJ day−1) for S. officinalis were calculated from laboratory estimates of energy losses due to standard (MO2 Standard), routine (MO2 Routine) and feeding (MO2 SDA) oxygen consumption. Laboratory estimates of daily metabolic expenditures were combined with results from previous investigations to construct an energy budget for 1 and 5 g cuttlefish consuming a meal of 5 and 15% Dw at 20°C and the amount of energy available for growth was estimated to be between 35 and 80.3% of the ingested energy.  相似文献   

20.
Communal rearing of offspring may help mothers maximize their investment in offspring at a reduced cost to their own bodily condition, thus maximizing their potential for reproductive success. The objective of this study was to quantify the costs and benefits of communal rearing to prairie vole (Microtus ochrogaster) pups and mothers. Mothers were assigned to one of three social units: solitary mothers, singularly breeding groups (i.e. one mother and one non-reproductive sister) and plurally breeding groups (i.e. two lactating sisters). For each type of social unit, some replicates were provided with food ad libitum, while others were provided with limited food. The body mass of focal mothers (i.e. the first mother to produce a litter) was a significant predictor of pup growth. Regardless of food availability, litters of focal mothers in plurally breeding groups gained more weight than litters reared by solitary mothers. Pups reared in singularly breeding groups were intermediate in weight gain, but did not gain significantly more weight than solitary offspring. There was no difference in the body mass of focal mothers from each type of social unit, regardless of food availability. Within plurally breeding groups, the weight gain of the two litters and body mass of focal and second mothers did not differ. However, focal mothers from plurally breeding groups nursed fewer pups than solitary mothers and also fewer pups than their nestmates when food was limited. Our results suggest that plural breeding results in greater fitness to mothers than solitary and singular breeding.Communicated by E. Korpimäki  相似文献   

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