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121.
生物安全是当前人们普遍关心的问题,它的影响涉及国家安全、人类社会及生态环境等诸多方面,其中由病原微生物引起的生物安全问题直接关系到动物疾病和人类健康,其重要性尤为突出,当前一些传染病的流行与我们的生物安全防范意识薄弱,措施不当有着直接的关系,必须引起我们的高度重视。我国兽用生物制品生物安全的管理问题主要表现在以下两个方面:一是如何进一步加强对兽用疫苗的质量管理和流通领域的监控,二是严格规范和控制从事动物病原微生物操作的实验室生物安全条件。对前者,我们有相应的法律法规和管理办法,关键的问题是如何进一步落实的…  相似文献   
122.
孙承骞  冯宁 《野生动物》2009,30(4):227-228
2009年2月28日,在陕西省成阳市沣渭湿地观测到18只家麻雀,并清晰拍摄到其中的2只(一雄一雌),经有关鸟类专家进一步鉴定是雀形目雀科家麻雀,该种为陕西省鸟类新纪录.  相似文献   
123.
The aim of this study was to estimate genetic parameters for coat color in horses. Besides defining coat color classes (gray, chestnut, bay, and black), the phenotypes were also measured quantitatively according to standardized international procedures (Commission Internationale de l'Eclairage L*, a*, b*), where L* describes lightness, a* describes color saturation from red to green, and b* describes color saturation from yellow to blue. The total color saturation was derived from a* and b* and referred to as Chroma. A total of 294 horses from the breeds Lipizzan, Nonius, Arabian Pure Bred, Shagya Arabian, and Gidran were measured at neck, shoulder, and belly. Heritabilities (within and between breeds or color classes) and repeatabilities were estimated using REML from univariate animal models defined separately for gray and nongray horses. For gray horses, the estimated within-breed heritabilities for L* ranged from 0.45 to 0.49 and for a*, b*, and Chroma from 0.09 to 0.52, indicating moderate polygenic effect. For nongray horses, between-color class heritabilities were high (0.70 to 0.85) and within-color class heritabilities were negligible (except for L* measured on neck and belly, 0.21 and 0.34, respectively). Additionally, the importance of L* was described by the relation with the total melanin content of horse coat hair; for gray and nongray horses, a strong negative linear relationship was detected (P < 0.01). The spectrometric measures and the results of this study demonstrate a possible approach to the estimation of the polygenic component involved in coat color inheritance.  相似文献   
124.
为了研究湖南省衡阳市紫色土丘陵坡地恢复过程中土壤微生物生物量碳(SMBC)与水溶性有机碳(SWSOC)的变化特征。采用空间序列代替时间序列的方法,选用立地条件基本相似的草坡阶段(GT)、草灌阶段(MT)、灌丛阶段(FX)、灌乔阶段(FA)、乔木阶段(AR)和顶极阶段(TV),通过调查取样和试验分析,对不同恢复阶段的0~10,10~20和20~40 cm土层土壤的SMBC、土壤微生物熵(SMQ)、SWSOC、水溶性有机碳与土壤有机碳的比值(SWSOC/SOC)、土壤基础呼吸(SBR)的变化规律以及他们与土壤理化性质的关系进行了研究。结果表明:SMBC和SBR随着土层深度的增加而减小,随着恢复的进行而增加;SMQ随着土层深度的增加和恢复进行而增加;在不同的恢复阶段,SWSOC均随着土层深度的增加而减小,在0~10 cm土层,SWSOC随着恢复的进行而增加,在10~20和20~40 cm土层,SWSOC随着恢复的进行先增后减;SWSOC/SOC随着土层深度的增加而增加,随着恢复的进行而减小;SMBC,SMQ,SWSOC,SBR均与土壤理化性质存在密切的相关性。研究表明,植被恢复有利于土壤质量的提高和土壤有机碳库的累积。  相似文献   
125.
Cow's milk stimulates growth in neonates and supplementation with specific milk proteins may benefit immuno-compromized neonates exhibiting poor growth. We investigated the effects of specific milk proteins (casein and whey) and plant protein (hydrolysed soy) on body and organ growth and bone mineralization in colostrum-deprived newborn pigs. Six days after birth, both casein and whey increased body and small intestinal weight relative to soy protein. Villus morphology and epithelial permeability were similar among groups. Casein significantly increased bone mineralization, while whey stimulated soft tissue growth (internal organs, muscle and fat). The differential effects of casein and whey proteins in the early postnatal period show that specific milk proteins rapidly affect whole body and gut development, even in a state of impaired growth induced by artificial feeding of colostrum-deprived pigs.  相似文献   
126.
Thirteen female Bedouin goats living in arid land of Algeria Sahara desert were used in this study. These goats were pregnant but they sustained an abortion because of unidentified causes. None of the goats showed any signs of general disease. Plasma concentrations of caprine pregnancy‐associated glycoproteins (cPAGs) and progesterone (P4) were determined during pregnancy using radioimmunoassay. The cPAGs concentration was undetectable (<0.8 ng/ml) throughout the first 2 weeks of gestation. From week 3 after mating, cPAGs concentration was detectable with significant individual variations (p < 0.05) reaching a maximum secretion (436.1 ng/ml). Throughout gestation, cPAGs concentration remained relatively constant but decreased few days before abortion, on an average of 9.2 ± 1.2 days (n = 11), except for two females where the concentrations decreased later (1–2 days before abortion). One or two peaks of cPAGs concentrations (in 4/13 and in 9/13 females, respectively) have been measured few weeks before abortion (77–124 days after mating), when a decline of cPAGs was detected. The P4 concentration increased after mating, and was high from the first week till the end of pregnancy. The P4 concentration (9.1 ± 0.9 ng/ml) decreased rapidly (<0.5 ng/ml) after 4 ± 0.7 days (n = 6) or 9.4 ± 1.6 days (n = 7) before abortion. A positive relationship (p < 0.01) was found between P4 and cPAGs concentrations during gestation. Results indicate that cPAGs and P4 measurements can be used for monitoring gestation and for abortion prediction.  相似文献   
127.
Horses at pasture are susceptible to the aspiration of foreign bodies. In Curitiba, southern Brazil, four horses of different breeds and ages were examined with regards to a persistent cough that lasted for several months, fetid breath, and no fever. The animals were referred for bronchoscopic examination performed under sedation and tracheobronchial topical anaesthesia. Bronchoscopies in all four horses revealed a pine branch of the species Araucaria angustifolia, native to southern Brazil, in the lumen of a third to fifth generation bronchus. Complete removal of the branch was possible in one case using a polypectomy loop inserted through the biopsy channel of the bronchoscope. In two cases, partial removal was possible. In one case the branch was adhered to the swollen mucosa and could not be extracted; this animal is being kept at pasture with intermittent antibiotic treatment as necessary. In conclusion, foreign bodies consisting of pine branches in the tracheobronchial tree of horses may be more common than currently recognised, as Araucaria genus is present in other countries and should be suspected in horses with chronic coughing associated with fetid breath and a history of reoccurrence following symptomatic treatments.  相似文献   
128.
129.
Survey of Toxoplasma antibodies among sheep in western United States   总被引:1,自引:0,他引:1  
A survey was conducted to determine the prevalence of toxoplasma antibodies among breeding ewes and among lambs slaughtered for food in western United States. Each serum was tested by the indirect hemaglutination method, using microtiter technique. Agglutination (greater than or equal to 2 +) at the 1:64 dilution was considered to be a positive reaction. Of 2,164 ewes from 18 flocks tested in California, 523 (24%) were seropositive for Toxoplasma gondii, with prevalence rates among flocks ranging from 4 to 51%. In 9 of those flocks, 1,495 ewes were stratified by whether ewes had lambed or were barren. On an overall basis, the antibody prevalence was similar (about 25%) in both groups, but there was a significant difference (P less than 0.05) in 1 flock in which 30% of the nursing ewes were seropositive, compared with 21% of the barren ewes. Of 1,056 market lambs from 19 lots tested, 85 (8%) were seropositive. The antibody prevalence in lambs tested at slaughter in California, by state of origin, were: Oregon, 11/51 (22%); Nevada, 32/159 (20%); Idaho, 12/147 (5%), and California, 30/699 (4%).  相似文献   
130.
为研究化脓隐秘杆菌(A.pyogenes) CbpA蛋白的反应原性,本研究以A.pyogenes H1j1005株为模板采用PCR方法扩增cbpA基因,并构建重组表达质粒pET-cbpA,将其转化至大肠杆菌感受态细胞Rosetta (DE53)plysS中,经IPTG诱导,用SDS-PAGE及western blot检测目的蛋白的表达情况及其反应原性.SDS-PAGE分析表明获得了约120 ku的蛋白.Western blot检测表明,CbpA蛋白可以与A.pyogenes阳性血清发生特异性反应,表明其有良好的反应原性.  相似文献   
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