McWilliams S R, Karasov W H
Department of Natural Resources Science, University of Rhode Island, Kingston, RI 02881, USA.
Comp Biochem Physiol A Mol Integr Physiol. 2001 Mar;128(3):579-93. doi: 10.1016/s1095-6433(00)00336-6.
Birds during migration must satisfy the high energy and nutrient demands associated with repeated, intensive flight while often experiencing unpredictable variation in food supply and food quality. Solutions to such different challenges may often be physiologically incompatible. For example, increased food intake and gut size are primarily responsible for satisfying the high energy and nutrient demands associated with migration in birds. However, short-term fasting or food restriction during flight may cause partial atrophy of the gut that may limit utilization of ingested food energy and nutrients. We review the evidence available on the effects of long- and short-term changes in food quality and quantity on digestive performance in migratory birds, and the importance of digestive constraints in limiting the tempo of migration in birds. Another important physiological consequence of feeding in birds is the effect of diet on body composition dynamics during migration. Recent evidence suggests that birds utilize and replenish both protein and fat reserves during migration, and diet quality influences the rate of replenishment of both these reserves. We conclude that diet and phenotypic flexibility in both body composition and the digestive system of migratory birds are important in allowing birds to successfully overcome the often-conflicting physiological challenges of migration.
在迁徙过程中，鸟类必须满足与反复进行的高强度飞行相关的高能量和营养需求，同时常常面临食物供应和食物质量不可预测的变化。应对这些不同挑战的解决方案在生理上可能常常相互矛盾。例如，增加食物摄入量和肠道大小主要负责满足鸟类迁徙相关的高能量和营养需求。然而，飞行期间的短期禁食或食物限制可能会导致肠道部分萎缩，这可能会限制对摄入食物能量和营养的利用。我们综述了现有关于食物质量和数量的长期和短期变化对候鸟消化性能影响的证据，以及消化限制在限制鸟类迁徙节奏方面的重要性。鸟类进食的另一个重要生理后果是饮食对迁徙期间身体成分动态的影响。最近的证据表明，鸟类在迁徙过程中会利用并补充蛋白质和脂肪储备，饮食质量会影响这两种储备的补充速度。我们得出结论，候鸟身体成分和消化系统的饮食及表型灵活性对于鸟类成功克服迁徙过程中常常相互冲突的生理挑战至关重要。
