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1.
All feces produced during 24 h were collected from five pigs and cortisol and immunoreactive cortisol metabolites (CICM), and IgA were quantified. Within pigs, the concentrations of CICM and IgA varied extensively between random samples obtained from a single fecal dropping, and deviated in most cases significantly from the true concentration measured in total fecal output (CV 6.7-130%). The CICM and IgA contents varied considerably (CV 8.1-114%) within and between individual fecal droppings from the same pig compared to the total fecal excretion. In conclusion, single random samples could not be used to reliably quantify the total fecal concentration or excretion of CICM or IgA in pigs. Analyses of all feces collected during shorter periods than 24 h did not provide an accurate estimate of the daily excretion of CICM. Thus, the concentration of stress sensitive molecules in random single fecal samples as an indicator of animal welfare should be interpreted with prudence.  相似文献   
2.
江苏省畜禽粪便污染现状与防治对策   总被引:10,自引:0,他引:10  
张绪美  董元华  王辉  沈旦 《土壤》2007,39(5):708-712
根据2000年以来江苏省畜禽饲养状况的有关资料,利用各类畜禽粪便日排泄系数估算畜禽粪便量,在此基础上计算江苏省各地畜禽粪便污染负荷量。研究发现,江苏省畜禽养殖业产生的粪便及各类污染物数量巨大,盐城市产生的粪便及各类污染物居全省首位,南通市次之;江苏省畜禽粪便污染负荷量平均为16.5t/(hm~2·a),南通市畜禽粪便污染负荷量最高,达26.7t/(hm~2·a)。全省畜禽粪便污染负荷最高的县是南通市的海安县,其次是盐城市的盐都县。最后本文分析了畜禽粪便污染环境的主要原因并提出了畜禽养殖污染防治的对策。  相似文献   
3.
Asian bears face major threats due to the impact of human activities as well as a critical lack of knowledge about their status, distribution and needs for survival. Once abundant in northern Pakistan, the Himalayan brown bear (Ursus arctos isabellinus) has been exterminated in most of its former distribution range. It presently occurs sparsely, in small populations, the Deosai National Park supporting the largest isolate. This decline might imply a reduction in genetic diversity, compromising the survival of the population. Using a combination of fecal DNA analysis and field data, our study aimed at assessing the size and genetic status of the Deosai population and give guidelines for its conservation and management. Using fecal genetic analysis, we estimated the population to be 40-50 bears, which compares well with the field census of 38 bears. The northern Pakistani brown bear population may have undergone an approximate 200-300-fold decrease during the last thousand years, probably due to glaciations and the influence of growing human population. However, in spite of the presence of a bottleneck genetic signature, the Deosai population has a moderate level of genetic diversity and is not at immediate risk of inbreeding depression. Gene flow might exist with adjacent populations. We recommend careful monitoring of this population in the future both with field observations and genetic analyses, including sampling of adjacent populations to assess incoming gene flow. The connectivity with adjacent populations in Pakistan and India will be of prime importance for the long-term survival of Deosai bears.  相似文献   
4.
采集林麝DNA样本获得快捷、有效的DNA提取方法是其分子标记,良种遗传选育的分子基础。以林麝粪便为研究对象,用常规和改良的方法比较提取林麝粪便DNA的效率,两种方法分别设为对照组和试验组。采集林麝粪便后分别在空气暴露0、2、4、6d。用对照组和试验组两种方法提取粪便DNA,以林麝GAPDH为目的基因,用PCR方法扩增样本。琼脂糖凝胶电泳分离DNA目的条带,以空气暴露0d的粪便DNA条带光密度值为参考,2、4、6d粪便DNA条带光密度值与0d进行比较获得相对光密度值。结果发现,随着时间延长,林麝粪便逐渐失去光泽,表面粗糙;对照组和试验组两种方法均能有效提取林麝DNA。试验组2d和4d与0d相比较DNA水平显著上升,6d与0d没有显著差异;对照组仅在2d提取的DNA水平上升,而4d和6d显著下降到0d的水平。以对照组为参照,两组各时间点相比,试验组获得的DNA水平显著高于对照组。研究结果表明,试验组提取DNA的方法可显著提高林麝粪便DNA的获得率。  相似文献   
5.

Background

Bovine paratuberculosis is an incurable chronic granulomatous enteritis caused by Mycobacterium avium subspecies paratuberculosis (MAP). The prevalence of MAP in the Swiss cattle population is hard to estimate, since only a few cases of clinical paratuberculosis are reported to the Swiss Federal Food Safety and Veterinary Office each year.Fecal samples from 1,339 cattle (855 animals from 12 dairy herds, 484 animals from 11 suckling cow herds, all herds with a history of sporadic paratuberculosis) were investigated by culture and real-time polymerase chain reaction (PCR) for shedding of MAP.

Results

By culture, MAP was detected in 62 of 445 fecal pools (13.9%), whereas PCR detected MAP in 9 of 445 pools (2.0%). All 186 samples of the 62 culture-positive pools were reanalyzed individually. By culture, MAP was grown from 59 individual samples (31.7%), whereas PCR detected MAP in 12 individual samples (6.5%), all of which came from animals showing symptoms of paratuberculosis during the study. Overall, MAP was detected in 10 out of 12 dairy herds (83.3%) and in 8 out of 11 suckling cow herds (72.7%).

Conclusions

There is a serious clinically inapparent MAP reservoir in the Swiss cattle population. PCR cannot replace culture to identify individual MAP shedders but is suitable to identify MAP-infected herds, given that the amount of MAP shed in feces is increasing in diseased animals or in animals in the phase of transition to clinical disease.  相似文献   
6.
采用单因素试验设计,选用(28±3)日龄、起始体重约(8.2±0.9)kg的二元杂种猪(L×Y)90头,随机分为5个处理,3重复/处理,6头/重复,分别饲喂粗蛋白质水平为16.5%、17.6%、18.7%、19.8%、20.9%的等能(3 300 MJ/kg)等氨基酸模式(Dlys∶D-SAA∶DThr∶DTrp=100∶57∶64∶18)的日粮,进行为期28d的饲养试验,研究5种不同粗蛋白质水平日粮对早期断奶仔猪生产性能、粪便微生物及部分血液生化指标的影响。结果表明,CP水平从16.5%增加至18.7%,仔猪平均日增重、平均日采食量线性增加,而料肉比线性降低;CP从18.7%进一步增加至20.9%,仔猪平均日增重、平均日采食量线性降低,料肉比线性增加,生产性能的各项指标呈二次曲线变化,蛋白质水平为18.7%时各项生产性能指标达到最优,因此以生产性能作为评价指标早期断奶仔猪最适宜的CP水平为18.7%。仔猪腹泻率,粪便大肠杆菌的数量以CP水平20.9%最高;血清总蛋白、白蛋白含量以及白蛋白/球蛋白先增加后降低,CP19.8%组含量最高,但未与CP18.7%达显著差异;血清尿素氮先增加后降低,CP19.8%组最高,但各组差异不显著(P>0.05)。  相似文献   
7.
[目的]提高粪便中犬弓首蛔虫卵的漂浮效果.[方法]对常用的饱和盐水漂浮法进行改良,对2份含犬弓首蛔虫卵的粪便进行漂浮和沉淀等处理.[结果]采用改良漂浮法2个粪便样本中虫卵的回收率分别为52.66%和38.90%,其回收效果较常规漂浮法有明显提高.[结论]采用吸取表层漂浮液的方式回收漂浮液,对虫卵的回收效果良好.  相似文献   
8.
靳勇超  张明海 《野生动物》2012,33(3):152-157,169
中国马鹿分为东北亚种、天山亚种、塔里木亚种、甘肃亚种、川西亚种、阿拉善亚种、西藏亚种和阿尔泰亚种。根据文献资料系统性总结了以粪便为研究材料对中国马鹿各个亚种的分子生态学的研究现状,展望了中国马鹿分子生态学需要研究的问题;具体介绍了马鹿分子生态学中研究很少的亲权鉴定、近亲交配和家域利用方面的研究现状并提出了进一步的研究趋势。为中国马鹿的种群恢复、保护管理以及科学研究提供依据。  相似文献   
9.
本文采用野外罩枝放养幼虫以及观察林间样树上幼虫一昼夜自然落粪数等方法对危害枣树的枣步曲幼虫的排粪量的特性进行了研究 ,并应用排粪量来推算枣树上的虫口密度。结果表明 :枣步曲幼虫的排粪量与日平均气温及昼夜温度的变化密切相关 ,但各龄幼虫间变化不大 ;枣步曲幼虫的排粪量随着龄期的增长而呈几何级数增加 ;枣步曲幼虫在枣树上的分布比较均匀 ,各方位间无显著差 ;建立了以日平均气温和排粪量为自变量来推算出虫口密度的动态模型n =mF =m1 6849+0 81 42T  相似文献   
10.
应用蔗糖离心尼龙网筛法、福尔马林乙醚沉淀法和饱和蔗糖漂浮法,对来自青海省的83份藏獒的粪便,进行棘球绦虫虫卵检查。结果:上述三法的阳性检出率分别为18.07%(15/83),15.66%(13/83)和13.25%(11/83)。  相似文献   
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