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71.
大猿叶虫Colaphellus bowringi Baly卵的颜色有浅黄色和深红色2种类型。调查卵的颜色与其后代滞育的发生和繁殖力的关系,结果表明,在25℃、28℃,不同光周期L∶D(11∶13,12∶12,13∶11和15∶9)下,浅黄色卵和深红色卵的后代滞育率没有显著差异;但在L14∶D10下,浅黄色卵的后代滞育率(25℃为58.6%;28℃为33.9%)显著高于深色卵的后代(25℃为45.4%;28℃为11.2%)。卵的颜色与其后代成虫的产卵前期和成虫寿命没有显著相关,但浅黄色卵后代的平均产卵量和平均日产卵量(1663粒和58.6粒)均显著高于深红色卵的后代(1176粒和45.1粒)。  相似文献   
72.
How feather colour reflects its carotenoid content   总被引:9,自引:1,他引:9  
  相似文献   
73.
菊苣提取物和菊粉降脂活性研究   总被引:2,自引:0,他引:2  
以300日龄商品代尼克T粉壳蛋鸡为试验动物,研究了菊苣提取物和菊粉对血清脂质、蛋黄总脂和胆固醇的影响.结果显示,0.1%菊苣提取物组、2.0%菊苣提取物组和0.1%菊粉组血清胆固醇(TC)、甘油三脂(TG)、低密度脂蛋白(LDL-C)均显著低于对照组(P<0.05),其中0.1%菊苣提取物组TC降低36.47%,TG降低40.71%,LDL-C降低36.09%,0.1%菊粉组LDL-C降低16.23%,差异极显著(P<0.01);2.0%菊苣提取物组高密度脂蛋白(HDL-C)比对照组高23.19%,差异极显著(P<0.01);2.0%菊苣提取物组蛋黄总脂和蛋黄胆固醇显著降低(P<0.05).表明菊苣提取物和菊粉均具有降血脂活性,但菊苣提取物比菊粉活性更强;菊苣提取物还具有降低蛋黄总脂和胆固醇的作用.  相似文献   
74.
The inner layer of vitelline membrane is an investment of avian ovum at the time of ovulation, but its formation is poorly understood. In order to elucidate the origin of the inner layer of vitelline membrane, a 33 kDa protein, one of the components of the inner layer, was purified from quail eggs and polyclonal antibody was raised against this protein. The tissue distribution of protein interacted with the antibody was studied by Western blotting technique. No immunoreactive component could be observed in extracts of liver, kidney, heart, lung, small intestine, brain, infundibulum, albumen-secreting region of oviduct, uterus, and wall of small white follicles. The intensive band was detected in the granulosa layer, which was isolated from the large preovulatory follicles as a monolayer of granulosa cells sandwiched between the inner layer of vitelline membrane and the basal lamina. The granulosa cells isolated from the granulosa layer also reacted with this antibody. Theca layer had no immunoreactive components. The position of the band of the 33 kDa protein on SDS-PAGE was sifted to higher molecular weight in follicular tissues as compared with that in the laid eggs, indicating that the structural change of the protein occurs after ovulation. These studies indicate that the material reactive to the antibody raised against a 33 kDa protein of quail vitelline membrane is synthesized by the granulosa cells.  相似文献   
75.
The trade‐off between offspring size and number can present a conflict between parents and their offspring. Because egg size is constrained by clutch size, the optimal egg size for offspring fitness may not always be equivalent to that which maximizes parental fitness. We evaluated selection on egg size in three turtle species (Apalone mutica, Chelydra serpentina and Chrysemys picta) to determine if optimal egg sizes differ between offspring and their mothers. Although hatching success was generally greater for larger eggs, the strength and form of selection varied. In most cases, the egg size that maximized offspring fitness was greater than that which maximized maternal fitness. Consistent with optimality theory, mean egg sizes in the populations were more similar to the egg sizes that maximized maternal fitness, rather than offspring fitness. These results provide evidence that selection has maximized maternal fitness to achieve an optimal balance between egg size and number.  相似文献   
76.
卵袋是雌蛛产卵、若蛛孵化等繁育后代的保护性场所.常见农林蜘蛛横纹金蛛(Argiopebruennichi)一般一生产卵3~6次,织制卵袋3~6个.本文对横纹金蛛的体重、卵袋生物量、卵粒数与卵粒重进行了测试研究.结果表明,随着产卵次数增加,产卵间隔时间更长,但雌蛛产卵后至下一次产卵前生物量的增量在减少,而对卵袋生物量的投...  相似文献   
77.
重金属 Ni2+ 对亚洲玉米螟生长发育和生殖行为的影响   总被引:1,自引:0,他引:1  
【目的】探索农田重金属Ni2+污染对植食性昆虫潜在的影响。【方法】在人工饲料中添加不同浓度(1, 5, 10, 15和20 mg/kg)的重金属Ni2+,以不添加重金属的人工饲料为对照,实验室条件下饲养亚洲玉米螟 Ostrinia furnacalis (Guenée)初孵幼虫,系统观察其各项生长发育和生殖行为指标参数。【结果】Ni 2+对亚洲玉米螟幼虫期、蛹期、化蛹率和羽化率有抑制作用;对亚洲玉米螟雌蛹重有促进作用,但随Ni2+浓度的升高而逐渐减弱;低浓度Ni2+(1~10 mg/kg)对雄蛹重有促进作用,高浓度Ni2+(15~20 mg/kg)对雄蛹重有抑制作用。随着Ni2+浓度的增加,亚洲玉米螟雌蛾平均求偶持续时间逐渐减小;1 mg/kg Ni2+浓度下雌蛾求偶率及求偶高峰期出现的时间与对照组基本一致,其余4个Ni2+浓度都对雌蛾求偶行为产生影响且表现为求偶高峰期出现的时间提前,最高求偶率均小于100%。5 mg/kg Ni2+对亚洲玉米螟雄蛾定向行为有促进作用,其余浓度则表现为抑制作用。Ni2+对亚洲玉米螟雌蛾的产卵量和卵孵化率均产生了显著的抑制作用。【结论】重金属Ni2+对亚洲玉米螟的生长发育和生殖行为产生了影响。  相似文献   
78.
The objective of the present study was to investigate the effect of feeding two transgenic corn lines containing the mCry1Ac gene from Bacillus thuringiensis strain (BT-799) and the maroACC gene from Agrobacterium tumefaciens strain (CC-2), respectively, on growth, egg quality and organ health indicators. Expression of the mCry1Ac gene confers resistance to Pyrausta nubilalis and the maroACC gene confers tolerance to herbicides. Healthy hens (n=96 placed in cages; 3 hens/cage) were randomly assigned to one of four corn–soybean meal dietary treatments (8 cages/treatment) formulated with the following corn: non-transgenic near-isoline control corn (control), BT-799 corn, CC-2 corn and commercially available non-transgenic reference corn (reference). The experiment was divided into three 4-week phases (week 1 to 4, week 5 to 8 and week 9 to 12), during which hens were fed mash diets. Performance (BW, feed intake and egg production) and egg quality were determined. Following slaughter at the end of 12 weeks of feeding (n=8/treatment), carcass yield and organ weights (heart, liver, spleen, lung, kidneys, stomach and ovary) were recorded; organs and intestines were sampled for histological analysis. Analysis of serum biochemistry parameters to assess the liver and kidney function were performed. No differences in BW, egg production and production efficiency were observed between hens consuming the control diet and hens consuming the BT-799 or CC-2 diet. Haugh unit measures and egg component weights were similar between the control and test groups. Carcass yield was not affected by the diet treatment. Similar organosomatic indices and serum parameters did not indicate the characteristics of organ dysfunction. All observed values of the BT-799 and CC-2 groups were within the calculated tolerance intervals. This research indicates that the performance, egg quality, organ health and carcass yield of laying hens fed diets containing the BT-799 or CC-2 corn line were similar to that of laying hens fed diets formulated with the non-transgenic near-isoline corn with comparable genetic backgrounds.  相似文献   
79.
The objective of this experiment was to replace soya bean oil with glycerol in laying hen diets and assess the change’s effect on performance, parameters of egg quality and the egg fatty acid profile. A total of 60 44-week-old Hy-Line W36 laying hens were distributed according to a completely randomised experimental design into four treatments consisting of glycerol substitutions for soya bean oil dietary at varying inclusion levels (0%, 25%, 50% and 75%), with five replicates of three birds each. Dietary treatments had no significant effect on BW change, egg production, feed intake, feed conversion ratio, egg weight and egg mass of laying hens. The inclusion of glycerol in the diet of laying hens had no significant effect on egg specific gravity, eggshell breaking strength, eggshell weight, eggshell thickness, egg shape index, albumen index, yolk index, haugh unit, albumen pH, yolk pH and egg yolk colour values. The inclusion of glycerol in the diet of laying hens had no significant effect on palmitic, palmitoleic, stearic, oleic and linolenic acid contents of the egg yolk. The linoleic acid and polyunsaturated fatty acid contents of the egg yolk significantly decreased with the higher levels of dietary glycerol supplementation (P<0.05). The results of this study show that it is possible to replace 75% of soya bean oil (4.5% in diet) with glycerol.  相似文献   
80.
以矢竹(Pseudosasa japonica)、花叶矢竹(P. japonica f. akebonosuji)和曙筋矢竹(P. japonica f. akebono)为研究对象, 借助叶绿体超微结构和荧光动力学曲线的变化揭示不同叶色矢竹的光系统活性及光合特性差异。结果表明: 3个竹种的光合色素含量差异明显, 除花叶矢竹条纹叶白色部分叶绿体内无完整类囊体片层结构外, 花叶矢竹绿条纹和曙筋矢竹的基粒数明显少于矢竹, 叶绿体发育成熟度不一致; OJIP曲线及参数表明, 花叶矢竹条纹绿叶和曙筋矢竹光系统II (PSII)反应中心开放降低程度低于矢竹, 捕获能量用于电子传递的份额变小, PSII活性变弱; 而曙筋矢竹叶片P700至初级电子受体(QA)的电子传递链氧化还原平衡偏向于还原侧, 推测其光系统I (PSI)反应中心P700至PSII QA电子传递链受损。因此, PSII活性变化导致叶绿体发育不成熟, 可能是引起矢竹类叶色差异的直接原因。  相似文献   
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