不同发情阶段雄性鹅喉羚的时间分配特征

The characteristics of time budgets of male goitred gazelle in different rutting period stages

以往研究表明受发情交配行为制约,一些雄性反刍动物在发情期食物摄入量明显降低。已有两个相关假说解释该现象:能量摄入最大化假说和能量保存假说。作者于2009～2010年在卡拉麦里山有蹄类自然保护区研究了雄性鹅喉羚不同发情阶段的时间分配。结果表明雄羚发情期采食时间比例明显下降(37.9%),低于发情前期(63.6%)和发情后期(65.8%);发情期卧息时间比例(6.0%)与发情后期相近(5.4%),明显低于发情前期(23.2%);发情前期至发情后期采食卧息时间比(分别为2.7、6.3、12.1)显著增加;发情期雄羚站立和移动时间比例明显升高,采食行为时间占非发情行为时间主要部分(86.4%),且采食行为与发情行为显著相关。相比之下,雌羚不同发情阶段采食行为时间分配比例相似。总之,除必需投入的发情行为外,发情期雄羚最大化其能量摄入;发情行为的投入是导致发情期雄羚食物摄入量下降的主导因子,雄性能量摄入最大化假说更好地解释了发情期鹅喉羚所采取的能量策略。

Several researchers have shown that male ruminants reduce forage intake sharply during the rutting season. Two hypotheses could explain this rut-induced hypophagia： a foraging-constraint hypothesis, and an energy-saving hypothesis. We compared the time budgets of male goitred gazelle before, during and after the rut in Kalamaili Nature Reserve during 2009 - 2010. The results showed that the percentage time of spent feeding decreased dramatically in rut （37.9%） com- pared to before （63.6%） and after rut （65.8%）. Lying time during rut （6.0%） was notably lower than during pre-rut （23.2%）, and similar with that of post-rut （5.4%）. The ratio of feeding and lying continuously increased across differ- ent stages of rut （2. 7, 6. 3 and 12. 1, respectively）. During rut, percentages time spent standing and moving were signifi- cantly higher than during pre- and post-rut. Most of non-rut time was allocated to feeding time （86. 4% ） , and a negative correlation between feeding and rutting time emerged. In contrast, time budgets of female were similar in different stages of rut. In conclusion, male goitred gazelle maximized their energy intake when not engaged in rutting behaviors during rut season. The increase of rutting behaviors was expected to be at the expense of feeding time. Accordingly, the foraging- constraint hypothesis explains the rutting-induced hypophagia of goitred gazelle better.