Daytime activity budgets of feral goats （ Capra hircus ） were studied in 1981, 1982 and 2000 on the Isle of Rum, northwest Scotland. This paper analyzes the influence of key weather variables （temperature and rainf...
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Daytime activity budgets of feral goats （ Capra hircus ） were studied in 1981, 1982 and 2000 on the Isle of Rum, northwest Scotland. This paper analyzes the influence of key weather variables （temperature and rainfall） and seasonal variations in daylength on daytime activity budgets. This study showed that the percentage of daytime spent in feeding by feral goats on Rum Island decreased with average monthly temperature, while the percentage of daytime spent in lying increased and rainfall had no significant effects on the percentage daytime spent in feeding or lying. The daylength varied greatly from January to December with the longest daylength being in June and July, and the shortest one in December and January. The amount of daytime spent feeding decreased from summer to winter, although the percentage of daytime spent feeding increased greatly from summer to winter. The seasonal variations in daylength seem to be an important factor in constraining feral goats＇ activity, especially in the cold and wet winters when forage biomass and quality are both at their lowest level. We discuss the influence of such constraining effects on the forage intake of these goats and their winter survival rate, as well as its implication for population regulation of these goats.
杨树受损伤后能诱导一些基因的表达,其编码的蛋白质可能在杨树的防卫反应中起一定作用。用PCR方法从新疆杨叶片中克隆出一个损伤诱导型Kun itz胰蛋白酶抑制剂基因PaTI1。序列分析表明:此基因不含内含子,其翻译起点上游具有‘TATA’和‘CCAAT’等转录控制元件,包含的阅读框架能编码一个长为213个氨基酸的多肽。此多肽与克隆自美洲山杨的PtTI2和PtTI1氨基酸序列同源性最高,分别为95%和80%,其N端存在一长度为27个氨基酸的信号肽。将此基因以融合蛋白的形式在大肠杆菌中进行表达,纯化后的融合蛋白对胰蛋白酶的活性有抑制作用,每8.5μg融合蛋白可完全抑制1μg牛胰蛋白酶的活性。W estern b lot分析表明融合蛋白与PtTI2特异的抗体之间有明显的血清学反应。
It is generally accepted that climate has changed greatly on a global scale, and that the earth＇s climate has already wanned by some degrees over the past century. Ample evidence shows that there have been apparent c...
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It is generally accepted that climate has changed greatly on a global scale, and that the earth＇s climate has already wanned by some degrees over the past century. Ample evidence shows that there have been apparent changes in avian population dynamics, life-history traits and geographic ranges in response to global climate change. This paper briefly reviews the possible effects of climate change on avian biology and ecology all over the world, with emphasis on new findings from several long-term studies in Europe and North America, which provide unique opportunities to investigate how long-term changes in climate affect birds at both individual and population levels. The implications of such long-term studies for future bird studies in China is discussed with hope that this review can contribute to the preparation and plan for studies of climatic effects on birds in China in the future.
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