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1.
Daily 20-hour encephalic photophases (DEPP), transmitted (hours 0 to 20) via chronically implanted light-conducting fibers to selected sites in the basal hypothalamus of male white-crowned sparrows, were superimposed on daily 8-hour (hours 0 to 8) external ambient photophases (DAPP). Initially the birds displayed motor activity only during the 8-hour DAPP. After a delay of at least 2 weeks, some of the birds became intensively active during hours 8 to 20. We postulate that this period of "nocturnal" activity is equivalent to the nocturnal Zugunruhe shown by caged individuals of many nocturnally migratory species subjected to long days; such activity is generally regarded as the expression of migratory behavior.  相似文献   

2.
Blind house sparrows (150 birds) and normal ones (199 birds) were subjected to various photoperiodic treatments consisting of cycles of 12 hours light, 12 hours dark and 16 hours light, 8 hours dark at intensities ranging from 20 to 500 lux. The testicular, response of the blind birds was found to be indistinguishable from the response of normal birds under these conditions. The data show that a functional extraretinal photoreceptor exists in this species which is fully capable of mediating the gonadal response to photoperiodic stimuli.  相似文献   

3.
Increase in body weight, spontaneous running activity, and adrenal cortical function have been studied in rats exposed to a random lighting schedule. In two separate experiments, grouped control animals were given 12 or 14 hours of light alternating with 12 or 10 hours of darkness, respectively, while coresponding grouped experimental animals were given the same total amounts of light and darkness per 24 hour period in a randomized pattern. Random light for periods of 17 to 40 days exerted no influence on growth rate, on weights of endocrine organs, or on adrenal response to adrenocorticotrophic hormone. However, the physiological fluctuation of group running activity and adrenal steroid secretion was abolished. Group desynchronization and the development of circadian rhythms having periods both shorter and longer than 24 hours appear to have replaced the synchronized group rhythmicity.  相似文献   

4.
[目的]为消除滞育对蝴蝶产业的不利影响。[方法]利用人工气候箱,对光周期与光脉冲对美凤蝶滞育蛹发育影响进行了研究。[结果]结果表明,20℃LD12:12时,滞育蛹第31天开始羽化,持续36d,平均历期46.9d;LD15:9时第37天开始羽化,持续22d,平均历期47.7d。25℃时,LD12:12开始羽化时间为第18天,持续23d,平均历期25.9d;LD15:9为第19d,持续14d,平均历期为26.4d。在25℃时,断光后间隔2h进行2h光脉冲处理,羽化推迟4d,在第19天开始羽化,平均历期延长1.2d,为21.8d;断光4h后进行2h光脉冲处理,羽化提早2d,第15天开始羽化,平均历期缩短1.9d,为18.8d。[结论]光周期和光脉冲对滞育蛹发育均有一定影响,但影响不显著。  相似文献   

5.
东方白鹳(Ciconia ciconia boycina)于每年三月中、下旬迁来黑龙江省兴凯湖自然保护区繁殖。巢筑在沼泽地的柳树上部,用于柳枝搭成,巢径210厘米,巢体高63厘米,距地面高3—4米。4月1日前后交配产卵,隔日产卵1枚,每年产卵4—5枚。孵化期为32天,每天雌雄交替孵化4次。育雏期每3小时左右采食一次。据1987、1988年人工饲养的幼雏各2只观察,幼雏生长发育迅速,日采食量350克(6日令)—2000克(50日令)。3日令可击喙发声,6日令长出飞羽芽,17日令长出正羽,50日令能站立,60日令自由活动,65日令试飞,70日令自由飞翔。跗跖长、体长、翼长分别于50、60、70日令前增长显著,之后便停止增长。体重增倍的间隔日期依次是2.5、3、4、6、20天,60日令后增长缓慢以致停止增加。喙长则持续而缓慢地增长。  相似文献   

6.
谭祥  吉奇 《安徽农业科学》2012,40(1):408-410
[目的]分析近57年本溪山区日照变化特征。[方法]利用本溪市草河口气象站1954~2010年逐月日照时数以及与相关的总云量、水汽压和≥0.1 mm降水日数等气候资料,运用线性倾向率、Mann-Kendall和小波分析等方法,对近57年本溪山区日照时数的变化特征及影响日照减少的可能气象因素进行分析。[结果]近57年来,本溪山区除冬季日照时数呈不显著增长趋势外,其他年、季日照时数呈显著减少趋势;年日照时数在1971年发生突变。总云量、水汽压和≥0.1 mm降水日数对日照时数影响比较明显,但日照时数并不是简单随着云量和≥0.1 mm降水日数的减少而增加,说明影响日照时数变化影响因素比较复杂。[结论]该研究为合理利用山区光能资源,调整农业产业结构和促进农业经济可持续发展提供科学依据。  相似文献   

7.
梨胶锈重寄生菌对垂丝海棠锈菌重寄生的研究   总被引:7,自引:1,他引:7  
本文对梨胶锈菌(GymnosporangiumasiaticumMiyabeexYamada)的重寄生菌(Tu berculinavinosaSac.)在垂丝海棠锈菌(GymnosporangiumyamadaiMiyabe)上的寄生形态、侵入及控病作用作了报道。重寄生菌在垂丝海棠锈菌的性子器及性子器相对的叶背面均可发生。它完成侵入所需的最短时间为7小时,潜育期8─9天。该菌重寄生率从4月下旬的23.3%,逐渐上升至6月中旬的90.9%。  相似文献   

8.
为深入了解不同波长光照对母鸡生产性能的影响机理,用c-Fos法探讨了母鸡间脑对不同波长光照的反应,同时检测GnRH免疫反应神经元的动态变化。将150日龄母鸡右眼遮光7 d后接受20 lx的不同波长光照刺激1.5 h,暗适应1.5 h后灌流固定,取脑制作石蜡切片,采用免疫组化方法检测Fos蛋白和GnRH样免疫反应阳性神经元在间脑的分布。结果显示,不同波长光照均影响c-fos基因表达和GnRH的释放,绿光组和蓝光组的表达均高于红光组。  相似文献   

9.
The universal cell mediator nitric oxide (NO) mediating the physiological effects via so-called NO donor compounds prolonging its life time. The concentration of NO metabolites in the pancreatic juice of chicken was determined by the enzymatic sensor. It was found that pancreatic juice from starved birds contains nitrate and no other nitro- or nitroso compounds. After feeding, the NO donors appear in pancreatic juice in concentrations of a few tens of μM. These compounds were present in pancreatic juice for several hours after feeding. It is possible that NO donors promote relaxation of the smooth muscles in the walls of pancreatic ducts. Concentration of NO donors in blood serum also increased 2.5–3.0-fold after feeding and remained high during a few subsequent hours. The preliminary subcutaneous administration of atropine to the birds prevent this increase with no effects on the initial concentrations of NO donors in serum. This suggests that the increase is associated with cholinergic stimulation and, therefore, with the activity of the parasympathetic nervous system. The concentration of trypsin in serum also increased after feeding, and atropine also prevents this increase. It is known that serum trypsin acts as a regulator of pancreatic function. Intravenous administration of trypsin led to an insignificant increase of tryptic activity in serum but induced the increase of NO donor concentration twofold. Apparently, nitric oxide, represented by these compounds, can act as a humoral factor in the regulation of pancreatic function in pancreatic juice and possibly in the blood.  相似文献   

10.
【目的】采用LED(light emitting diodes)灯作为光源,探讨孵化期间歇性单色光刺激对肉仔鸡出雏后生产性能、胸肉化学成分及肉品质的影响。【方法】1 480枚爱拔益加(AA)鸡商品代受精蛋(蛋重65-70 g,平均重68 g)被随机分配到绿光组(560 nm,490枚)、蓝光组(480 nm,490枚)和黑暗组(对照组,500枚)3种不同处理的孵化器中,采用间歇光照(15 min开灯,15 min关灯),光照强度为15 lx。肉仔鸡出壳后,从每个处理组各选取120只公雏分配到3个处理中,每个处理6个重复,每个重复20只鸡。自由采食和饮水,统一采用30 lx日光灯补光,光照时间23L﹕1D。【结果】各处理组种蛋孵化率、肉仔鸡初生重及平均采食量均无显著差异(P>0.05)。与黑暗组和蓝光组相比,胚胎期绿光刺激可显著增加肉仔鸡21和42 d体重(P<0.05)。42 d时,绿光组肉仔鸡的胸肌重和胸肌率均最高,分别较黑暗组提高了38.3 g和0.67%,较蓝光组提高了44.6 g和0.78%。整个生长期绿光组饲料转化率为1.81,显著优于黑暗组(1.88)和蓝光组(1.92,P<0.05)。各组肉仔鸡42 d胸肌化学成分无显著差异(P<0.05)。蓝光组胸肌24 h肉色b*值显著高于黑暗组和绿光组(P=0.05),而绿光处理组胸肌滴水损失(P=0.10)和蒸煮损失(P=0.07)均较黑暗组和蓝光组有升高的趋势。【结论】孵化期15 lx间歇绿光刺激可促进肉仔鸡肌肉生长,提高胸肌产量并改善饲料转化率,对胸肌化学成分无显著影响(P>0.05),但绿光组肉仔鸡胸肌系水力有降低的趋势。  相似文献   

11.
小麦收获前穗发芽的生理生化特性研究   总被引:21,自引:2,他引:19  
1984-1986年两个生长季节,先后研究了41个小麦品种(系)收获前穗发芽的生理生化特性。研究结果表明,供试品种(系)的穗发芽抗性有显著的差异。穗上发芽率与α-淀粉酶活性、降落值、籽粒吸水6、12、24小时的电导率和呼吸强度、籽粒吸水速率等的相关较高,与内源ABA含量之间的相关较低,以上这些性状除内源ABA含量外,品种(系)间有显著的差异,穗发芽抗性较强的品种的α-淀粉酶活性、籽粒吸水后的电导率和呼吸强度及籽粒吸水初期的吸水速率均比穗发芽抗性较弱的品种低,降落值与此相反。浸湿籽粒的α-淀粉酶活性、降落值、籽粒吸水24小时的电导率和吸吸强度、籽粒吸水0-75分钟的吸水速率等可作为穗发芽抗性的选择指标。鉴定穗发芽抗性时,最好在模拟雨湿条件下,既直接测定穗发芽情况,同时也采用多种选择指标,对穗发芽抗性作出综合评价。  相似文献   

12.
以1800只海兰雏鸡为试验材料,培育于青年鸡场;从130日龄起易地饲养于新安县某产蛋鸡饲养专业户,同时由青年鸡场一体的饲料厂供应源于同一套配方的配合饲料.结果表明,青年鸡与产蛋鸡易地专业化饲养切实可行.青年鸡亚系统,130日龄鸡的体重略高于标准,每只鸡的饲料成本为13.8元,盈利5.5元.产蛋鸡亚系统,91%以上的产蛋率维持12周,料蛋比2.7:1;90%以上的产蛋率期间,千只鸡的日盈利为141.8元.  相似文献   

13.
应用聚丙烯酰胺凝胶电泳研究了水分胁迫下板栗幼苗过氧化物酶、超氧物岐化酶同工酶谱的变化,并分别测定了酶活力.结果表明:随胁迫处理时间的延长,两种同工酶的谱带都发生变化,诱导出新的谱带;轻度中度胁迫下,两种酶的活力明显增加,随胁迫程度的增强,酶活性增加缓慢.  相似文献   

14.
The running-wheel activity pattern of mature male rats was successfully synchronized to light-dark cycles as long as 48 hours and as short as 16 hours. Even after 6 months' exposure to "days" longer than the normal 24 hours, the animals returned promptly to circadian rhythmicity when placed under freerunning conditions of continuous dark. That such rhythms also reappeared when the light condition of the 36-hour cycle was reduced from 660 to 33 lumens per square meter suggests that brightness may be the critical factor in the unexpectedly broad range of entrainment demonstrated.  相似文献   

15.
Entrainment of circadian rhythms by sound in Passer domesticus   总被引:2,自引:0,他引:2  
The circadian locomotor rhythm of house sparrows was entrained by a sound stimulus. The birds were maintained at a constant temperature in, dim green light. The entraining agent was 4 (1/2) 12 hours of tape-recorded bird song ,played each day. Variations in the response to this stimulus have been correlated with individual variations in free-running period. This is the first clear demonstration that a biological clock can be influenced by sound stimuli.  相似文献   

16.
鸡传染性法氏囊病病毒的分离与鉴定   总被引:10,自引:0,他引:10  
从安徽省合肥郊县疑似传染性法氏囊病的雏鸡体内,分离到4株病毒。经血清学、人工感染、鸡胚接种、分子生物学试验鉴定,结果表明,分离物为传染性法氏囊病病毒(IBDV)。人工感染易感鸡试验表明,4株中有2株具有超强毒株的致病特点。将其接种36日龄鸡后第2天精神沉郁,拉白色或绿色稀粪,发病率为100%。第3~4天出现死亡高峰,死亡率达80%。剖检可见全身性出血素质,法氏囊呈“紫葡萄”样外观。接种鸡胚后72~96 h引起鸡胚全部死亡。另外2株接种易感鸡后,发病率和死亡率都较低,临床症状不典型,出现亚临床传染性法氏囊病,剖检病理变化不明显,表明此2株毒力较弱。  相似文献   

17.
Three adult cats were deprived of rapid eye movement sleep for six separate periods of up to 32 days. Animals were allowed normal amouints of sleeping time during which rapid eye movement sleep was interrupted, whenever it occurred, by human observers who continually monitored the animals and their electrocortical activity. Cortical responses evoked by pairs of acoustic clicks were recorded during wakefulness. Recovery functions derived from these data were facilitated during periods of deprivation of rapid eye movement sleep and returned to base-line values when animals were allowed normal amounts of this sleep phase. This change was noted repeatedly within, as well as between, subjects. It did not occur during control periods when non-rapid eye movement sleep was interrupted on identical schedules, nor did it occur when the cats were deprived of all sleep for 22 hours a day for 5 days.  相似文献   

18.
Mediation of photoperiodic effects by indoleamines, especially melatonin, is known in higher vertebrates. A similar mechanism may occur in a unicellular alga, the dinoflagellate Gonyaulax polyedra. This organism entered the dormant stage of a cyst upon short-day treatment at lowered temperatures. Interruption of darkness by 2 hours of light prevented cyst formation, even when the overall duration of light was the same as in cyst-inducing short days. When given in a noninducing photoperiod, melatonin and an analog, 5-methoxytryptamine, substances that had previously been shown to occur in Gonyaulax, provoked cyst formation. Methoxylated indoleamines may play a role as mediators of darkness in this unicellular, in a similar way as in vertebrates, suggesting a common biochemical basis of photoperiodism.  相似文献   

19.
实验尝试在旋转生物反应器(RCCS)中采用微载体培养技术对心肌细胞进行快速培养。采用顺序消化和差速贴壁法分离纯化1~2日龄新生大鼠的心肌细胞,并将其在RCCS内应用Cytodex-3微载体进行培养,于倒置显微镜和扫描电镜下对微载体表面的细胞进行动态观察,同时测定细胞的代谢活性。结果表明,心肌细胞可快速贴附于微载体表面,细胞伸展后生长加速,并可形成心肌细胞-微载体团块,细胞代谢旺盛,说明在RCCS内应用微载体培养技术可简便、快速地在体外培养心肌细胞,是心肌细胞培养的一条可行途径。  相似文献   

20.
以黄化小麦苗为材料 ,在无钙 (-Ca2 )和有钙 ( Ca2 )两种条件下 ,结合不同类型抑制剂以及红光、远红光和白光等不同光质处理 ,初步探讨了光调节小麦叶片谷氨酰胺合成酶 (GS)活性的机理。结果表明 ,黄化小麦叶片经连续 72h光诱导后 ,其GS活性达到正常绿叶水平。有钙培养的小麦幼苗叶片谷氨酰胺合成酶活性高于无钙处理。光对GS活性的调节存在多级水平 ,首先是光对GS的直接激活作用 ,该过程有光敏色素的参与 ,而光敏色素可能是通过钙调系统而起作用的 ,其红光 /远红光逆转效应需要钙的参与 ;其次是光诱导GS的重新合成 ,短期调节主要是从翻译水平上起作用 ,受环己亚胺的抑制 ,长期调节则是在转录水平上发挥作用 ,受放线菌素D的影响  相似文献   

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