Comparison of the nutrient contents of the principal forage plants ulilized by lesser snow geese on summer breeding grounds
Comparison of the nutrient contents of the principal forage plants ulilized by lesser snow geese on summer breeding grounds
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夏季繁殖地小雪雁利用的主要饲草植物养分含量比较
DOI：
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发表时间：
1995
期刊：
影响因子：
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通讯作者：
R. Jefferies
中科院分区：
文献类型：
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作者：
F. Gadallah;R. Jefferies
1. 繁殖地的雏鹅和成年小雪雁在夏季需要大量的营养物质生长，并为秋季迁徙建立储备。由于鸟类本质上是草食性的，因此需要高营养品质的饲料来满足营养需求。 2. 马尼托巴省拉彼鲁斯湾夏季孵化后的首选饲料品种（Carex subspathacea、Puccinellia phryganodes）比替代饲料品种（Festuca rubra、Calamagrostis deschampsioides、Carex aquatilis、C. x flavicans）具有更高的营养成分。鹅似乎能够检测出高营养品质的饲料。 3、鹅生长饲料中潜在短缺的三种元素是氮、钙、磷。优选的盐沼草料中这些元素的含量大致满足鹅的估计饮食需求。优选和替代饲料品种中钾、镁、钠和锰的含量足以满足鹅的生长。这些估计是基于家鹅的需求。 4. 首选盐沼饲料品种的可用性减少以及替代饲料品种的使用增加与小鹅体型的长期下降有关。在北极其他地方，这六种饲料物种不存在或很少出现，但小雪雁的雏鹅成功地长出了羽毛，这表明存在能够满足鸟类营养需求的饲料物种行会。已知两个这样的物种，Dupontia Fisheri 和 Arctophila fulva，其营养成分与本研究中检查的盐沼禾本科植物相当。
1. Goslings and adult lesser snow geese on the breeding grounds require large amounts of nutrients in summer for growth and to build reserves for autumnal migration. As the birds are essentially herbivorous, forage of high nutritional quality is required to meet nutritional demands. 2. Preferred forage species (Carex subspathacea, Puccinellia phryganodes) during the post-hatch period in summer at La Perouse Bay, Manitoba, have a higher nutrient content than alternative forage species (Festuca rubra, Calamagrostis deschampsioides, Carex aquatilis, C. x flavicans). Geese appear able to detect forage of high nutritional quality. 3. The three elements that were potentially in short supply in the forage for the growth of geese were nitrogen, calcium, and phosphorus. Quantities of these elements in the preferred salt-marsh forage broadly met the estimated dietary requirements of the geese. Amounts of potassium, magnesium, sodium and manganese in both preferred and alternative forage species were adequate for the growth of the geese. These estimates were based on the requirements of domestic geese. 4. The reduced availability of the preferred salt-marsh forage species and the increased use of alternative forage species are associated with a long-term decline in gosling size. Elsewhere in the Arctic where these six forage species do not occur or are infrequent, goslings of lesser snow geese fledge successfully, which indicates that there are guilds of forage species capable of meeting the nutritional demands of the birds. Two such species, Dupontia fisheri and Arctophila fulva, are known to have nutrient contents comparable to the salt-marsh graminoids examined in this study.