[树]麻雀羽再生的能量预算和水代谢散热调节

The energy budget and water metabolism heat regulation of tree sparrows Passer montanus of toba compensatory regeneration

为探讨[树]麻雀的羽再生能力、能量预算对策和有效的散热调节方式,对3组(对照CF、去飞羽FF和去尾羽组TF)[树]麻雀(Passer montanus)进行4周驯养(Acclimation)。结果发现:[树]麻雀具有较强的羽再生能力和飞羽参与个体保温。羽再生[树]麻雀能量收支水平降低极显著(P﹤0.001),FF组和TF组比CF组减少依次为:摄入能19.77%和7.17%、消化能18.79%和6.47%、同化能18.73%和6.46%、粪能28.66%和13.35%、水代谢散热热能26.95%和7.43%、排泄次数33.71%和14.40%,增加依次为:消化率1.23%和0.78%、同化率1.35%和0.84%。个体能值水平,体重CF、TF和FF组(P﹤0.05)依次降低,体温组间变化不显著(P﹥0.05)。体内能量储备,血糖、肌糖原、体脂和水分含量组间差异不显著(P﹥0.05),肝糖原含量、体脂重组间差异显著(P﹤0.05)。器官水平包括心脏、肾脏、腺胃、小肠、盲肠和总消化道长度及质量出现积极的响应。日代谢水量组间差异极显著(P﹤0.001)。组间日排泄次数最少平均为56.11次和最多可达96.34次/只。结果表明:羽再生[树]麻雀分别选择了不同程度的降低能量收支水平,提高摄入食物的消化、吸收效率,动用体内能量储备来获取摄入能量不足部分,降低器官总能耗的能量预算对策和不同的新羽(再生羽枚数:飞羽部分和尾羽全部)再生的能量投资对策。泄殖腔排出(粪尿混合物)水是鸟类特有的、迅速的和有效的散热调节方式。

We compared differences in feather regeneration ability, energy budgets, organs levels, and heat regulation in molting Tree sparrows （Passer montanus）. After one week of adaptation to laboratory conditions, thirty adult birds were assigned to three groups including control （CF, n = 10）, remove flight feathers （FF, n = 10） and remove tail feathers （TF, n= 10） by body mass and SPSS Tools. All three groups were monitored over a four-week period while exposed to similar environmental conditions. On a daily basis we measured food and water intake, the numbers of defecations, fecal mass, and so on. Feathers had strong regenerative capacities, and flight feathers were also important in heat regulation. The level of energy budget of birds declined （P 〈 0. 001）. FF and TF groups declined 19.77% and 7.17% in energy intake, 18.79% and 6.47% in digestible energy, 18.73% and 6.46% in assimilation energy, 28.66% and 13.35% in fecal energy, 26.95% and 7.43% in cooling heat energy of water metabolism, 33.71% and 14.40% in discharge frequency. FF and TF groups showed increases of 1.23% and 0.78% in digestion rate, and 1.35% and 0. 84% in assimilation rate, respectively, compared with the CF . Body weight in CF, TF and FF （P〈0. 05） declined but body temperature showed no obviouschange （P〉0.05）. In terms of energy reserves, including blood sugar, muscle glycogen, body fat and water content, no significant difference （P〉0. 05） was observed between the three groups, but liver glycogen content and body fat mass did differ （P〈0. 05）. Organ level, including heart, kidney, glandular stomach, small intestine, caecum and the length and quality of the total gastrointestinal tract showed a response to feather loss. Groups differed significantly in average daily water metabolism （P〈0. 001 ）. The minimum and maximum average number of defecations reached 56.11 times and 96.54 times, respectivel. Under low levels of environmental stress, P. montanus showed strong feather regeneration capacities. The differences between regenerating flight feathers and tail feathers is due to distinct energy investment strategies and energy-saving strategies, also including energy consumption in flight and energy saving strategy of water metabolism heat loss reduction. There was an obvious decline in the level of energy budget and energy reserve of P. montanus. Discharge water from the cloacae with feces and urine mixture is a peculiar, effective and rapid thermal loss regulation mode among birds. Different feather parts have an influence on individual insulation capability and movement capacity, which proves to be a main reason for differences in water metabolism heat dissipation. Birds regenerating feathers showed reduced organs mass, improved organ efficiency, and reduced energy expenditure by organs. Energy consumption of organs is an integral part of individual energy budgets. Organ functional capabilities are closely related to individual energy intake, transfer and storage. Changes in organ quality, functional capabilities and energy consumption are the organ-level responses to body energy budget strategies. Distinct energy budget strategies were adopted by P. montanus in the same living environment with three feather structures.