Millam J R
Department of Animal Science, University of California, Davis, California, USA.
Vet Clin North Am Exot Anim Pract. 1999 Jan;2(1):93-110. doi: 10.1016/s1094-9194(17)30141-x.
Studies of the behavior of Amazon parrots throughout a reproductive trial indicate that activities such as food gathering, which may occupy large fractions of the activity budget of wild parrots, occupy little time in captivity. This may be one factor contributing to the large percentage of time during which Amazon parrots are generally inactive in typical captive conditions. The extent of inactivity in captive Amazons creates an open time niche wherein enrichment devices might play a role in improving their well being. Studies of the reproductive endocrinology and the behavior of parrots suggest that hand rearing may impair adult fertility and nest box use. Hand rearing may also cause adult Cockatiels to lay eggs on cage floors rather than in nest boxes. However, the use of nest boxes with oversized nest entrances can be very effective in alleviating chronic floor laying in Cockatiels. Another egg-laying problem in Cockatiels, unwanted egg laying, can be prevented by the use of long-acting formulations of the superactive GnRH agonist, leuprolide acetate, which presumably [figure: see text] acts in birds, as in mammals, by down-regulating pituitary GnRH receptors. Manipulations to limit the increases in prolactin normally seen during incubation in poultry can significantly increase egg production. As clutch size in Cockatiels may also be limited by rising prolactin levels, such manipulations may be effective in stimulating egg production in parrots. An alternative approach for increasing flock egg production is to place foster eggs in nests of Cockatiel pairs that are slow to lay. This technique stimulates males to increase their nest-oriented behavior and, subsequently, may stimulate egg laying in some females that might not otherwise have laid eggs. The parental phases of reproduction in Amazon parrots are often a time of heightened aggressiveness towards humans, but low levels of serum testosterone in males during that time suggest that this particular interspecies aggressiveness may not be dependent on elevated testosterone levels. Occasional human handling during the nestling stage may produce a degree of tameness comparable with hand-reared chicks, yet not impair adult reproductive performance. Such handling may also alter the immune status of captive parrots, and possibly reduce the serum corticosterone response to handling. If so, occasional human handling during the nestling stage could improve the adaptation of parrots to captivity.
对亚马逊鹦鹉在整个繁殖试验过程中的行为研究表明，诸如觅食等活动，在野生鹦鹉的活动预算中可能占据很大一部分，但在圈养环境中所花费的时间却很少。这可能是导致亚马逊鹦鹉在典型圈养条件下大部分时间普遍不活动的一个因素。圈养的亚马逊鹦鹉不活动的程度创造了一个开放的时间生态位，在这个生态位中，丰富化装置可能有助于改善它们的健康状况。对鹦鹉繁殖内分泌学和行为的研究表明，人工育雏可能会损害成年鹦鹉的繁殖能力和对巢箱的使用。人工育雏还可能导致成年鸡尾鹦鹉在笼底而不是在巢箱中产蛋。然而，使用巢口超大的巢箱对于缓解鸡尾鹦鹉长期在笼底产蛋的情况非常有效。鸡尾鹦鹉的另一个产蛋问题，即异常产蛋，可以通过使用长效超活性促性腺激素释放激素（GnRH）激动剂醋酸亮丙瑞林来预防，据推测，它在鸟类中的作用方式与在哺乳动物中一样，是通过下调垂体GnRH受体来实现的。采取措施限制家禽孵化期间通常出现的催乳素升高，可以显著提高产蛋量。由于鸡尾鹦鹉的窝卵数也可能受到催乳素水平上升的限制，因此这些措施可能有效地刺激鹦鹉产蛋。增加鸟群产蛋量的另一种方法是在产蛋较慢的鸡尾鹦鹉对的巢中放置代孵蛋。这种技术会刺激雄性增加其筑巢行为，随后，可能会刺激一些原本不会产蛋的雌性产蛋。亚马逊鹦鹉繁殖的亲代阶段通常是对人类攻击性增强的时期，但在此期间雄性血清睾酮水平较低，这表明这种特定的种间攻击性可能不依赖于睾酮水平的升高。在雏鸟阶段偶尔进行人工照料可能会产生与人工育雏的雏鸡相当的温顺程度，同时又不会损害成年鹦鹉的繁殖性能。这种照料还可能改变圈养鹦鹉的免疫状态，并可能降低血清皮质酮对人工照料的反应。如果是这样，在雏鸟阶段偶尔进行人工照料可以改善鹦鹉对圈养环境的适应能力。
