中国最大的黄嘴白鹭繁殖群调查报告

黄嘴白鹭 (Egrettaeulophotes)在辽宁为夏候鸟。因其分布区域狭窄 ,数量较少 ,已被列为世界濒危鸟类之一。据已往资料 ,该鸟的繁殖种群地在旅顺海猫岛 ,种群数量大约为 6 0余只。 1997年 ,我们在长海县石城岛的杏仁砣 (形人砣 )发现了迄今为止国内有记录以来最大繁殖群 ,种群数量为 30 0余只。     

水貂育种核心群选育研究

在水貂育种核心群选育中,组建核心群,经过初选、复选、精选、同质选配等措施,培育出体型较大,繁殖力高,生长发育快,毛绒品质好,遗传性能稳定的左家黑色标准水貂优良品种。结果表明:三个世代的选育,母貂的胎产仔数达到了5.58±1.72只,成活数5.33±1.81只;公貂的受配率为91.3%。公貂体重为(2.29±0.18)kg,母貂体重为(1.28±0.14)kg;公貂体长为(44.6±2.17)cm,母貂体长为(38.21±1.32)cm。毛绒品质也得到了提高。结论:水貂体重,体长,繁殖性能,毛绒品质均有所提高,基本达到预期目标。     

Leaf N and P stoichiometry of 57 plant species in the Karamori Mountain Ungulate Nature Reserve,Xinjiang,China

Nitrogen(N) and phosphorus(P) are the major nutrients that constrain plant growth and development,as well as the structure and function of ecosystems.Hence,leaf N and P patterns can contribute to a deep understanding of plant nutrient status,nutrient limitation type of ecosystems,plant life-history strategy and differentiation of functional groups.However,the status and pattern of leaf N and P stoichiometry in N-deficiency desert ecosystems remain unclear.Under this context,the leaf samples from 57 plant species in the Karamori Mountain Ungulate Nature Reserve,eastern Junggar Desert,China were investigated and the patterns and interrelations of leaf N and P were comparatively analyzed.The results showed that the average leaf N concentration,P concentration,and N:P ratio were 30.81 mg/g,1.77 mg/g and 17.72,respectively.This study found that the leaf N concentration and N:P ratio were significantly higher than those of studies conducted at global,national and regional scales;however,the leaf P concentration was at moderate level.Leaf N concentration was allometrically correlated with leaf P and N:P ratio across all species.Leaf N,P concentrations and N:P ratio differed to a certain extent among plant functional groups.C_4 plants and shrubs,particularly shrubs with assimilative branches,showed an obviously lower P concentration than those of C_3 plants,herbs and shrubs without assimilative branches.Shrubs with assimilative branches also had lower N concentration.Fabaceae plants had the highest leaf N,P concentrations(as well as Asteraceae) and N:P ratio;other families had a similar N,P-stoichiometry.The soil in this study was characterized by a lack of N(total N:P ratio was 0.605),but had high N availability compared with P(i.e.the available N:P ratio was 1.86).This might explain why plant leaves had high N concentration(leaf N:P ratio>16).In conclusion,the desert plants in the extreme environment in this study have formed their intrinsic and special stoichiometric characteristics in relation to their life-history strategy.     

Influence of strain and flock age on geometrical and mechanical attributes of eggs produced from Japanese quail birds

We investigated how the geometrical and mechanical properties of eggshell of Japanese quail are affected by strain and flock age. Two strains of quail (white and gray) were used in the current experiment. The results showed that there was no significant difference for all geometric measurements due to strain effect. Eggs produced from the older birds showed significantly higher (P < 0.01) values compared with younger age for all studied traits. Eggs produced from quails at 22 weeks had a significantly (P < 0.01) darker yolk color than that of the younger age. Superiority in shell thickness, shell weight, and breaking force was detected in eggs of gray quails compared with white quails. On the other hand, the eggs from white quails had significantly higher values for static stiffness and Young's modulus as compared with those of gray counterparts. A significant decrease (P < 0.01) was found for fracture toughness and Young's modulus in eggs of aged birds. A significant negative relationship was found between the breaking force and both static stiffness and Young's modulus. A significant positive relationship was observed between breaking force and both shell thickness and shell percentage. The phenotypic correlation between eggshell breaking force and toughness was relatively high.     

口蹄疫自然感染动物与免疫动物鉴别诊断研究进展

口蹄疫是偶蹄动物高度接触性传染病 ,能引起巨大经济损失。国际兽医局将其列为 A类动物传染病之首。除发达国家外 ,大多数发展中国家都采用注射疫苗的办法来控制该病的流行。因此如何区分感染动物和免疫动物是口蹄疫防制中迫切需要解决的问题。目前口蹄疫灭活疫苗的生产工艺可以将绝大部分的非结构蛋白除去 ,因而灭活疫苗免疫动物只能产生结构蛋白抗体 ,而感染动物能产生结构蛋白抗体 ,也能产生非结构蛋白抗体 ,因此 ,检测非结构蛋白抗体为鉴别口蹄疫感染动物与免疫动物提供了美好前景。文章从鉴别诊断的原理 ,非结构蛋白的免疫特性 ,鉴别诊断所面临的问题及解决方案 ,应用非结构蛋白作为鉴别诊断抗原的研究现状等方面进行了综述。     

Pulmonary fibrosis in response to environmental cues and molecular targets involved in its pathogenesis

Chronic lung injury resulting from a variety of different causes is frequently associated with the develop ment of pulmonary fibrosis in humans. Although the etiology of pulmonary fibrosis is generally unknown, several sources of evidence support the hypothesis that a number of environmental and occupational agents play an etiologic role in the pathogenesis of this disease. The agents discussed in this review include beryllium, nylon flock, textile printing aerosols, polyvinyl chloride and didecyldimethylammonium chloride. The authors also describe a variety of animal models, including genetically modified mice, in order to investigate the molecular mechanism of pulmonary fibrosis, focusing on chemokine receptors, regulatory T cells and transforming growth factor-β and bone morphogenetic protein signaling. Overall, we propose the concept of toxicological pulmonary fibrosis as a lung disease induced in response to environmental cues.