食物组分差异对树麻雀能量代谢及消化道形态结构的影响
|
摘要
为探寻食物组分差异对小型鸟类生理生化指标和消化道的影响,了解小型鸟类如何通过自我调节以应对不良环境条件变化的生存策略。将树麻雀Passer montanus按体质量随机分为对照组(饲喂小米Setaria italica),稗草籽组(饲喂稗草Echinochloa crusgalli籽),黄粉虫组(饲喂黄粉虫Tenebrio molitor),8只·组-1,进行驯化,4周后通过烘干恒质量法、索氏抽提法、硫酸-蒽酮法、石蜡切片法等方法,测定其基础代谢率(basal metabolic rate,BMR)、体质量、器官鲜质量和干质量、体脂质量分数、糖原质量分数和消化道长度,消化道绒毛高度、宽度、黏膜层厚度及肠壁截面积等指标的变化。结果表明:饲喂4周后,3组树麻雀基础代谢率与第1周相比分别增加0.14,0.35和0.11 m L·g-1·h-1,稗草籽组与对照组和黄粉虫组差异显著(P<0.05),对照组与黄粉虫组差异不显著(P>0.05);体质量组间差异均极显著(P<0.01);黄粉虫组大肠、小肠、十二指肠、直肠、肌胃的鲜质量极显著高于稗草籽组和对照组(P<0.01),黄粉虫组十二指肠、肌胃的干质量极显著高于稗草籽组和对照组(P<0.01),对照组大肠、直肠的干质量极显著高于稗草籽组和黄粉虫组(P<0.01);稗草籽组和黄粉虫组的消化能、消化率与对照组间的差异极显著(P<0.01);3组树麻雀大肠、小肠、十二指肠长度组间差异均极显著(P<0.01),稗草籽组、黄粉虫组大肠绒毛高度与对照组间的差异均极显著(P<0.01),对照组、稗草籽组的小肠和十二指肠绒毛高度、黏膜层厚度与黄粉虫组间的差异均极显著(P<0.01)。表明食物组分差异是影响树麻雀能量代谢和消化道形态改变的重要环境因子之一。
This experiment was conducted to invesigate the effects of different food components on the physiological and biochemical indexes and digestive tract of small birds(Passer montanus), for understanding the survival strategy of P. montanus through self-regulation in response to adverse changes in environmental conditions. The birds were randomly divided into three groups: a control group(fed with millet-Setaria italica), a grass seed group(fed with grass-Echinochloa crusgalli seed), and a mealworm group(fed with mealwormsTenebrio molitor). The birds have been domesticating for four weeks until the relevant indicators were detected,such as the basal metabolic rate(BMR) and body mass, organ quality of fresh and dry weight, body fat mass fraction, glycogen content, length of the digestive tract and the digestive tract mucous membrane layer thickness and height, width, cross-section of the intestinal wall. Results showed that the basal metabolic rates of the birds in the three groups(control group, grass seed group, mealworm group) were increased by 0.14, 0.35 and 0.11 m L·g-1·h-1 respectively compared with the first week, and it was higher in the grass seed group than those in the other two groups(P <0.05). Body mass of the birds were all extremely significantly different between groups(P<0.01). Organ fresh weight of the large intestine, small intestine, duodenum and rectum were extremely significantly higher in the grass seed group than those in the grass seed group and control group(P<0.01). Dry weight of duodenum and muscle stomach of the birds in the mealworm group were extremely significantly higher than those in the grass group and control group(P <0.01), while dry weight of the colon and rectum in control group were extremely significantly higher than those in the grass group and mealworm group(P<0.01). Digestible energy and digestibility of the birds in the mealworm group was significantly higher than those in the grass group(P<0.01). The length of large intestine, small intestine, duodenum of the birds were extremely significant difference among the three groups(P<0.01). The heights of large intestinal villus in the grass seed group and mealworm group were extremely significantly different with those in the control group(P<0.01), and the height and mucosal layer thickness of small intestine and duodenum villus in the control group and grass seed group were all extremely significantly different with those in the mealworm group(P<0.01). The differences of food component is one of the important environmental factors that would influence energy metabolism and digestive tract morphological structure of P. montanus.
This experiment was conducted to invesigate the effects of different food components on the physiological and biochemical indexes and digestive tract of small birds(Passer montanus), for understanding the survival strategy of P. montanus through self-regulation in response to adverse changes in environmental conditions. The birds were randomly divided into three groups: a control group(fed with millet-Setaria italica), a grass seed group(fed with grass-Echinochloa crusgalli seed), and a mealworm group(fed with mealwormsTenebrio molitor). The birds have been domesticating for four weeks until the relevant indicators were detected,such as the basal metabolic rate(BMR) and body mass, organ quality of fresh and dry weight, body fat mass fraction, glycogen content, length of the digestive tract and the digestive tract mucous membrane layer thickness and height, width, cross-section of the intestinal wall. Results showed that the basal metabolic rates of the birds in the three groups(control group, grass seed group, mealworm group) were increased by 0.14, 0.35 and 0.11 m L·g-1·h-1 respectively compared with the first week, and it was higher in the grass seed group than those in the other two groups(P <0.05). Body mass of the birds were all extremely significantly different between groups(P<0.01). Organ fresh weight of the large intestine, small intestine, duodenum and rectum were extremely significantly higher in the grass seed group than those in the grass seed group and control group(P<0.01). Dry weight of duodenum and muscle stomach of the birds in the mealworm group were extremely significantly higher than those in the grass group and control group(P <0.01), while dry weight of the colon and rectum in control group were extremely significantly higher than those in the grass group and mealworm group(P<0.01). Digestible energy and digestibility of the birds in the mealworm group was significantly higher than those in the grass group(P<0.01). The length of large intestine, small intestine, duodenum of the birds were extremely significant difference among the three groups(P<0.01). The heights of large intestinal villus in the grass seed group and mealworm group were extremely significantly different with those in the control group(P<0.01), and the height and mucosal layer thickness of small intestine and duodenum villus in the control group and grass seed group were all extremely significantly different with those in the mealworm group(P<0.01). The differences of food component is one of the important environmental factors that would influence energy metabolism and digestive tract morphological structure of P. montanus.
引文
[1]宋志刚,王德华.哺乳动物基础代谢率的主要影响因素[J].兽类学报,2002,22(1):53-60.SONG Zhigang,WANG Dehua.Influcing factors on basal metabolic rate in mammals[J].Acta Theriol Sin,2002,22(1):53-60.
[2]王玉山,王德华,王祖望.动物长期能量收支理论及研究进展[J].动物学研究,2000,21(3):238-244.WANG Yushan,WANG Dehua,WANG Zuwang.The progress on the theory of long-term energy budget in animals[J].Zool Res,2000,21(3):238-244.
[3]LOVEGROVE B G.The influence of climate on the basal metabolic rate of small mammals:a slow-fast metabolic continuum[J].J Comp Physiol B,2003,173(2):87-112.
[4]徐兴军,邵淑丽,张伟伟,等.不同食物对麻雀肝糖原和肌糖原含量的影响[J].黑龙江畜牧兽医,2012(12):126-128.XU Xingjun,SHAO Shuli,ZHANG Weiwei,et al.Influence of different foods on the content of liver glycogen and muscle glycogen[J].Heilongjiang Anim Sci Vet Med,2012(12):126-128.
[5]ROZMAN J,RUNCIMAN D,ZANN R A.Seasonal variation in body mass and fat of Zebra finches in south-eastern Australia[J].Emu Austr Ornitho,2003,103(1):11-19.
[6]WILLIAMS J B,TIELEMAN B I.Flexibility in basal metabolic rate and evaporative water loss among hoopoe larks exposed to different environmental temperatures[J].J Exp Biol,2000,203(20):3153-3159.
[7]崔思荣.斑翅山鹑的食物能量代谢[J].佳木斯大学学报(自然科学版),2010,28(4):622-623.CUI Sirong.Food energy metabolism of partridge[J].J Jiarnusi Univ Nat Sci Ed,2010,28(4):622-623.
[8]杨志宏,邵淑丽.食物质量差异对树麻雀能量预算和消化道形态特征的影响[J].生态学报,2011,31(14):3937-3946.YANG Zhihong,SHAO Shuli.The influence of different food qualities on the energy budget and digestive tract morphology of tree sparrows Passer montanus[J].Acta Ecol Sin,2011,31(14):3937-3946.
[9]柳劲松,李铭,邵淑丽.树麻雀肝脏和肌肉产热特征的季节性变化[J].动物学报,2008,54(5):777-784.LIU Jinsong,LI Ming,SHAO Shuli.Seasonal changes in thermogenic properties of liver and muscle in tree sparrows Passer montanus[J].Acta Zool Sin,2008,54(5):777-784.
[10]阮向东.麻雀生态学研究进展[J].动物学杂志,1989,24(6):44-48.RUAN Xiangdong.Development of sparrow ecology[J].Chin J Zool,1989,24(6):44-48.
[11]张国凯,方媛媛,姜雪华,等.白头鹎的代谢率与器官重量在季节驯化中的可塑性变化[J].动物学杂志,2008,43(4):13-19.ZHANG Guokai,FANG Yuanyuan,JIANG Xuehua,et al.Adaptive plasticity in metabolic rate and organ masses among Pycnonotus sinensis,in seasonal acclimatization[J].Chin J Zool,2008,43(4):13-19.
[12]BARCEL魷G,SALINAS J,CAVIERES G,et al.Thermal history can affect the short-term thermal acclimation of basal metabolic rate in the passerine Zonotrichia capensis[J].J Therm Biol,2009,34(8):415-419.
[13]林琳,曹梦婷,胡益林,等.环境温度对白头鹎代谢产热和蒸发失水的影响[J].生态学报,2014,34(3):564-571.LIN Lin,CAO Mengting,HU Yilin,et al.Effect of environmental temperature on thermogenesis and evaporative water loss in Chinese bulbuls(Pycnonotus sinensis)[J].Acta Ecol Sin,2014,34(3):564-571.
[14]汪诗平,李永宏.放牧率和放牧时期对绵羊排粪量、采食量和干物质消化率关系的影响[J].动物营养学报,1997,9(1):47-54.WANG Shiping,LI Yonghong.The influence of different stocking rates and grazing periods on the amount of feces and its relationship to DM intake and digestibility of grezing sheep[J].Acta Zoonutr Sin,1997,9(1):47-54.
[15]AL-MANSOUR M I.Seasonal variation in basal metabolic rate and body composition within individual sanderling bird Calidris alba[J].J Biol Sci,2004,4(4):564-567.
[16]吴梦斯,赵丽丹,王润梅,等.画眉冬夏两季能量收支和消化道形态特征比较[J].生态学杂志,2015,34(4):1031-1037.WU Mengsi,ZHAO Lidan,WANG Runmei,et al.Comparison of energy budget and digestive tract morphology in Hwamei Garrulax canorus between winter and summer[J].Chin J Ecol,2015,34(4):1031-1037.
[17]徐兴军,邵淑丽,张伟伟,等.饥饿条件下麻雀体内糖原含量和基础代谢率的变化[J].江苏农业科学,2013,40(11):348-350.XU Xingjun,SHAO Shuli,ZHANG Weiwei,et al.In the body of tree sparrow glycogen content and BMR change under the condition of hunger[J].Jiangsu Agric Sci,2013,40(11):348-350.
[18]王昌河,谢振丽,吕建伟.动物组织石蜡切片H-E染色的快速方法[J].生物学通报,2012,47(7):50-51.WANG Changhe,XIE Zhenli,L譈Jianwei.A H-E dyeing fast method for animal tissue paraffin section[J].Bull Biol,2012,47(7):50-51.
[19]李兴升.布氏田鼠和长爪沙鼠血清瘦素对体重、能量摄入和产热的作用[D].北京:中国科学院,2005.LI Xingsheng.Effects of Serum Leptin on Body Weight,Energy Intake and Heat Production in Brandt’s voles and Mongolian gerbil[D].Beijing:Chinese Academy of Sciences,2005.
[20]COOPER S J.Daily and seasonal variation in body mass and visible fat in mountain chickadees and juniper titmice[J].Wilson J Ornithol,2007,119(4):720-724.
[21]WU Mengsi,XIAO Yuchao,YANG Fang,et al.Seasonal variation in body mass and energy budget in Chinese bulbuls(Pycnonotus sinensis)[J].Avian Res,2014,5:4.doi:10.1186/s40657-014-0004-8.
[22]ZHANG Weihong,LI Ming,LIU Jinsong,et al.Seasonal acclimatization of metabolism in Eurasian tree sparrows(Passer montanus)[J].Comp Biochem Physiol Part A Molr Integra Physiol,2008,151(4):519-525.
[23]赵志军,陈竞峰,王德华.光周期和高脂食物对布氏田鼠能量代谢和产热的影响[J].动物学报,2008,54(4):576-589.ZHAO Zhijun,CHEN Jingfeng,,WANG Dehua.Effects of photoperiod and high fat diet on energy intake and thermogenesis in brandt’s voles Lasiopodomys brandtii[J].Acta Zool Sin,2008,54(4):576-589.
[24]娄美芳.食物质量对布氏田鼠母体能量代谢、繁殖输出及后代代谢表型的影响[D].济南:山东师范大学,2013.LOU Meifang.Effects of Food Quality on Energy Metabolism,Reproductive Output and Offspring Metabolic Phenotype in Maternal Brandt’s Voles(Lasiopodomys brandtii)[D].Ji’nan:Shandong Normal University,2013.
[25]王有祥,徐兴军,邵淑丽,等.温度驯化对白腰朱顶雀脱支酶活性的影响[J].东北林业大学学报,2015,43(9):107-110.WANG Youxiang,XU Xingjun,SHAO Shuli,et al.Effects of temperature acclimatization on enzyme activity in Carduelis flammea debranching[J].J Northeast For Univ,2015,43(9):107-110.
[26]DOWD W W,BRILL R W,BUSHNELL P G,et al.Standard and routine metabolic rates of juvenile sandbar sharks(Carcharhinus plumbeus),including effects of body mass and acute temperature change[J].Fish Bull,2005,104(3):323-331.
[27]RINTAMAKI P T,STONE J R,LUNDBERG A.Seasonal and diurnal body-mass fluctuations for two nonhoarding species of parus in Sweden modeled using pathanalysis[J].Auk Orithol Adv,2003,120(3):658-670.
[28]刘丽,陈晓波,余红心,等.品种与日粮营养水平对鸡内脏器官质量及指数的影响[J].饲料研究,2010(11):49-51.LIU Li,CHEN Xiaobo,YU Hongxin,et al.Breed and daily ration nutritional level influence of chicken’s visceral organ mass and index[J].Feed Res,2010(11):49-51.
[29]宋志刚,王德华.内蒙古草原布氏田鼠代谢率与身体器官的关系[J].兽类学报,2003,23(3):230-234.SONG Zhigang,WANG Dehua.Relationship between metabolic rate and organ size in Brandt’s voles(Microtus brandti)[J].Acta Theriol Sin,2003,23(3):230-234.
[30]冯照军,季丽萍,施雯,等.中华蟾蜍糖原含量的季节变化[J].动物学报,2007,53(6):1048-1053.FENG Zhaojun,JI Liping,SHI Wen,et al.Seasonal changes of the glycogen content in Bufo gargarizans[J].Acta Zool Sin,2007,53(6):1048-1053.
[31]KARASOV W H,del RIO C M,CAVIEDESVIDAL E.Ecological physiology of diet and digestive systems[J].Ann Rev Physiol,2011,73(73):69-93.
[32]STARCK J M,RAHMAAN G H.Phenotypic flexibility of structure and function of the digestive system of Japanese quail[J].J Exp Biol,2003,206(11):1887-1897.
[33]PIERSMA T,DRENT J.Phenotypic flexibility and the evolution of organisnal design[J].Trends Ecol Evol,2003,18(5):228-233.
[2]王玉山,王德华,王祖望.动物长期能量收支理论及研究进展[J].动物学研究,2000,21(3):238-244.WANG Yushan,WANG Dehua,WANG Zuwang.The progress on the theory of long-term energy budget in animals[J].Zool Res,2000,21(3):238-244.
[3]LOVEGROVE B G.The influence of climate on the basal metabolic rate of small mammals:a slow-fast metabolic continuum[J].J Comp Physiol B,2003,173(2):87-112.
[4]徐兴军,邵淑丽,张伟伟,等.不同食物对麻雀肝糖原和肌糖原含量的影响[J].黑龙江畜牧兽医,2012(12):126-128.XU Xingjun,SHAO Shuli,ZHANG Weiwei,et al.Influence of different foods on the content of liver glycogen and muscle glycogen[J].Heilongjiang Anim Sci Vet Med,2012(12):126-128.
[5]ROZMAN J,RUNCIMAN D,ZANN R A.Seasonal variation in body mass and fat of Zebra finches in south-eastern Australia[J].Emu Austr Ornitho,2003,103(1):11-19.
[6]WILLIAMS J B,TIELEMAN B I.Flexibility in basal metabolic rate and evaporative water loss among hoopoe larks exposed to different environmental temperatures[J].J Exp Biol,2000,203(20):3153-3159.
[7]崔思荣.斑翅山鹑的食物能量代谢[J].佳木斯大学学报(自然科学版),2010,28(4):622-623.CUI Sirong.Food energy metabolism of partridge[J].J Jiarnusi Univ Nat Sci Ed,2010,28(4):622-623.
[8]杨志宏,邵淑丽.食物质量差异对树麻雀能量预算和消化道形态特征的影响[J].生态学报,2011,31(14):3937-3946.YANG Zhihong,SHAO Shuli.The influence of different food qualities on the energy budget and digestive tract morphology of tree sparrows Passer montanus[J].Acta Ecol Sin,2011,31(14):3937-3946.
[9]柳劲松,李铭,邵淑丽.树麻雀肝脏和肌肉产热特征的季节性变化[J].动物学报,2008,54(5):777-784.LIU Jinsong,LI Ming,SHAO Shuli.Seasonal changes in thermogenic properties of liver and muscle in tree sparrows Passer montanus[J].Acta Zool Sin,2008,54(5):777-784.
[10]阮向东.麻雀生态学研究进展[J].动物学杂志,1989,24(6):44-48.RUAN Xiangdong.Development of sparrow ecology[J].Chin J Zool,1989,24(6):44-48.
[11]张国凯,方媛媛,姜雪华,等.白头鹎的代谢率与器官重量在季节驯化中的可塑性变化[J].动物学杂志,2008,43(4):13-19.ZHANG Guokai,FANG Yuanyuan,JIANG Xuehua,et al.Adaptive plasticity in metabolic rate and organ masses among Pycnonotus sinensis,in seasonal acclimatization[J].Chin J Zool,2008,43(4):13-19.
[12]BARCEL魷G,SALINAS J,CAVIERES G,et al.Thermal history can affect the short-term thermal acclimation of basal metabolic rate in the passerine Zonotrichia capensis[J].J Therm Biol,2009,34(8):415-419.
[13]林琳,曹梦婷,胡益林,等.环境温度对白头鹎代谢产热和蒸发失水的影响[J].生态学报,2014,34(3):564-571.LIN Lin,CAO Mengting,HU Yilin,et al.Effect of environmental temperature on thermogenesis and evaporative water loss in Chinese bulbuls(Pycnonotus sinensis)[J].Acta Ecol Sin,2014,34(3):564-571.
[14]汪诗平,李永宏.放牧率和放牧时期对绵羊排粪量、采食量和干物质消化率关系的影响[J].动物营养学报,1997,9(1):47-54.WANG Shiping,LI Yonghong.The influence of different stocking rates and grazing periods on the amount of feces and its relationship to DM intake and digestibility of grezing sheep[J].Acta Zoonutr Sin,1997,9(1):47-54.
[15]AL-MANSOUR M I.Seasonal variation in basal metabolic rate and body composition within individual sanderling bird Calidris alba[J].J Biol Sci,2004,4(4):564-567.
[16]吴梦斯,赵丽丹,王润梅,等.画眉冬夏两季能量收支和消化道形态特征比较[J].生态学杂志,2015,34(4):1031-1037.WU Mengsi,ZHAO Lidan,WANG Runmei,et al.Comparison of energy budget and digestive tract morphology in Hwamei Garrulax canorus between winter and summer[J].Chin J Ecol,2015,34(4):1031-1037.
[17]徐兴军,邵淑丽,张伟伟,等.饥饿条件下麻雀体内糖原含量和基础代谢率的变化[J].江苏农业科学,2013,40(11):348-350.XU Xingjun,SHAO Shuli,ZHANG Weiwei,et al.In the body of tree sparrow glycogen content and BMR change under the condition of hunger[J].Jiangsu Agric Sci,2013,40(11):348-350.
[18]王昌河,谢振丽,吕建伟.动物组织石蜡切片H-E染色的快速方法[J].生物学通报,2012,47(7):50-51.WANG Changhe,XIE Zhenli,L譈Jianwei.A H-E dyeing fast method for animal tissue paraffin section[J].Bull Biol,2012,47(7):50-51.
[19]李兴升.布氏田鼠和长爪沙鼠血清瘦素对体重、能量摄入和产热的作用[D].北京:中国科学院,2005.LI Xingsheng.Effects of Serum Leptin on Body Weight,Energy Intake and Heat Production in Brandt’s voles and Mongolian gerbil[D].Beijing:Chinese Academy of Sciences,2005.
[20]COOPER S J.Daily and seasonal variation in body mass and visible fat in mountain chickadees and juniper titmice[J].Wilson J Ornithol,2007,119(4):720-724.
[21]WU Mengsi,XIAO Yuchao,YANG Fang,et al.Seasonal variation in body mass and energy budget in Chinese bulbuls(Pycnonotus sinensis)[J].Avian Res,2014,5:4.doi:10.1186/s40657-014-0004-8.
[22]ZHANG Weihong,LI Ming,LIU Jinsong,et al.Seasonal acclimatization of metabolism in Eurasian tree sparrows(Passer montanus)[J].Comp Biochem Physiol Part A Molr Integra Physiol,2008,151(4):519-525.
[23]赵志军,陈竞峰,王德华.光周期和高脂食物对布氏田鼠能量代谢和产热的影响[J].动物学报,2008,54(4):576-589.ZHAO Zhijun,CHEN Jingfeng,,WANG Dehua.Effects of photoperiod and high fat diet on energy intake and thermogenesis in brandt’s voles Lasiopodomys brandtii[J].Acta Zool Sin,2008,54(4):576-589.
[24]娄美芳.食物质量对布氏田鼠母体能量代谢、繁殖输出及后代代谢表型的影响[D].济南:山东师范大学,2013.LOU Meifang.Effects of Food Quality on Energy Metabolism,Reproductive Output and Offspring Metabolic Phenotype in Maternal Brandt’s Voles(Lasiopodomys brandtii)[D].Ji’nan:Shandong Normal University,2013.
[25]王有祥,徐兴军,邵淑丽,等.温度驯化对白腰朱顶雀脱支酶活性的影响[J].东北林业大学学报,2015,43(9):107-110.WANG Youxiang,XU Xingjun,SHAO Shuli,et al.Effects of temperature acclimatization on enzyme activity in Carduelis flammea debranching[J].J Northeast For Univ,2015,43(9):107-110.
[26]DOWD W W,BRILL R W,BUSHNELL P G,et al.Standard and routine metabolic rates of juvenile sandbar sharks(Carcharhinus plumbeus),including effects of body mass and acute temperature change[J].Fish Bull,2005,104(3):323-331.
[27]RINTAMAKI P T,STONE J R,LUNDBERG A.Seasonal and diurnal body-mass fluctuations for two nonhoarding species of parus in Sweden modeled using pathanalysis[J].Auk Orithol Adv,2003,120(3):658-670.
[28]刘丽,陈晓波,余红心,等.品种与日粮营养水平对鸡内脏器官质量及指数的影响[J].饲料研究,2010(11):49-51.LIU Li,CHEN Xiaobo,YU Hongxin,et al.Breed and daily ration nutritional level influence of chicken’s visceral organ mass and index[J].Feed Res,2010(11):49-51.
[29]宋志刚,王德华.内蒙古草原布氏田鼠代谢率与身体器官的关系[J].兽类学报,2003,23(3):230-234.SONG Zhigang,WANG Dehua.Relationship between metabolic rate and organ size in Brandt’s voles(Microtus brandti)[J].Acta Theriol Sin,2003,23(3):230-234.
[30]冯照军,季丽萍,施雯,等.中华蟾蜍糖原含量的季节变化[J].动物学报,2007,53(6):1048-1053.FENG Zhaojun,JI Liping,SHI Wen,et al.Seasonal changes of the glycogen content in Bufo gargarizans[J].Acta Zool Sin,2007,53(6):1048-1053.
[31]KARASOV W H,del RIO C M,CAVIEDESVIDAL E.Ecological physiology of diet and digestive systems[J].Ann Rev Physiol,2011,73(73):69-93.
[32]STARCK J M,RAHMAAN G H.Phenotypic flexibility of structure and function of the digestive system of Japanese quail[J].J Exp Biol,2003,206(11):1887-1897.
[33]PIERSMA T,DRENT J.Phenotypic flexibility and the evolution of organisnal design[J].Trends Ecol Evol,2003,18(5):228-233.