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11.
益生素预防畜禽腹泻机理的研究 总被引:7,自引:0,他引:7
用革兰氏阳性的嗜酸乳杆菌和枯草杆菌的活菌和死菌喂饲了80只雏鸡,用嗜酸乳杆菌的活菌和死菌喂饲了37头仔猪和24头犊牛,观察这些细菌防畜禽腹泻的效果。结果证明这两种细菌的活菌与死菌都有预防腹泻的功能,嗜酸乳杆菌的效果好于枯草杆菌。两种菌的活菌和死菌都有预防作用说明是菌体成分或代谢产物可能是预防腹泻的主要有效成分。 相似文献
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茉莉酸对苹果气孔运动及抗旱性的影响 总被引:5,自引:0,他引:5
50、75、100、150 mg/L JA处理苹果叶片表皮,使开放气孔的气孔开度分别减小27.4%、37.5%、56.9%和63.8%,使关闭后的气孔在光下开放时气孔开度分别减小15%、18%、28.8%、52.5%、61.3%;处理植株后干旱胁迫,叶片相对电导率分别降低15%、18%、31%、58%,脯氨酸含量分别提高0.09%、0.40%、0.42%、0.54 ng/gFW,可溶性糖含量分别提高1.89%、2.53%、3.80%、5.06%。25 mg/L JA处理与对照均无显著差别。JA的作用表现出明显的浓度效应。 相似文献
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低聚糖对雏鸡大肠粪便NH3-N含量及肠道菌群的影响 总被引:11,自引:0,他引:11
试验选取1日龄罗曼蛋公雏250只,随机分为5组,试验组饲料或饮水中分别添加海藻糖(500mg/kg)、海藻胶(600mg/kg)、大豆寡糖(500mg/kg)、圆葱寡糖(500mg/d)。结果表明,四种低聚糖均可促进肠道乳酸菌及双歧杆菌的生长繁殖,对魏氏梭菌的生长呈现抑制作用。海藻糖、海藻胶对降低大肠粪便NH3—N含量效果不显著(P>0.05),而大豆寡糖效果显著(P<0.05),圆葱寡糖效果极显著(P<0.01)。 相似文献
14.
《The Journal of Applied Poultry Research》2006,15(2):287-291
Campylobacter numbers on broiler carcasses can increase dramatically during defeathering because of leakage of contaminated gut contents in the feather-picking machine. Food-grade organic acids have been shown to be effective in killing bacteria. Placement of organic acids into the cloaca prior to defeathering was tested to determine if such a treatment could lower the number of Campylobacter that escape and contaminate broiler breast skin during automated feather removal. Campylobacter numbers on the breast skin of treated carcasses increased during defeathering but resulted in numbers that were only about 2% of those observed on control carcasses. Placement of food-grade organic acids in the cloaca of broiler carcasses may be useful as a means to lessen the impact of automated defeathering on the microbiological quality of carcasses during processing. 相似文献
15.
以兰山大白、株洲长白和英引3个苦瓜品种为材料进行外源激素处理对苦瓜植株性别表现影响的试验.结果表明,苗期进行GA325~100mg/L处理有明显的促雌效果;CCC50~200mg/L处理则有促雄效果,但促雄程度因品种而异,CCC500mg/L处理对兰山大白有适度的促雌作用.外源激素处理对苦瓜植株性别分化的影响可持续80d以上.苦瓜第一雌花形成与茎尖GA3含量达到峰值有关,25mg/L的GA3处理使茎尖GA3含量的峰值提前出现而使第一雌花形成提早,而100mg/LCCC处理使茎尖GA3含量先下降再逐渐回升而使植株第一雌花形成滞后 相似文献
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The plants of field bean var. Nadwiślaνski were detopped after about 1 month since the beginning of flowering and after that all flower buds were removed from some plants. The effect of a change in the trophic balance on the setting and subsequent growth of root nodules was studied.
The removal of pods had the greater effect on the increase in the weight of the remaining organs than the detopping of plants. Detopping retarded the ageing of the plants and delayed the phase of the greatest reduction of the number of pods. The detopping of plants revealed their considerable compensative possibilities in terms of production of the pod weight and the potential of leaves for biomass production. The data obtained indicate that plant detopping may disturb the root–bacteria exchange of signals, necessary to initiate the nodule development, while the further growth of nodules depends, above all, on the amount of available photosynthates.
A very high correlation between the dry weight of the whole plant to the dry weight of leaves ratio and the weight of nodules was observed. It proves the importance of the trophic balance of the plant for the root nodule weight production. 相似文献
The removal of pods had the greater effect on the increase in the weight of the remaining organs than the detopping of plants. Detopping retarded the ageing of the plants and delayed the phase of the greatest reduction of the number of pods. The detopping of plants revealed their considerable compensative possibilities in terms of production of the pod weight and the potential of leaves for biomass production. The data obtained indicate that plant detopping may disturb the root–bacteria exchange of signals, necessary to initiate the nodule development, while the further growth of nodules depends, above all, on the amount of available photosynthates.
A very high correlation between the dry weight of the whole plant to the dry weight of leaves ratio and the weight of nodules was observed. It proves the importance of the trophic balance of the plant for the root nodule weight production. 相似文献
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