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饲草青贮添加剂研究进展 总被引:2,自引:0,他引:2
为了提高饲草青贮发酵效率,改善发酵品质,调制青贮时常使用添加剂,文章综述了近年来青贮添加剂的研究进展。根据其作用机制青贮添加剂可以分为4类,分别是发酵促进型添加剂、发酵抑制型添加剂、好氧性变质抑制剂、营养型添加剂等。乳酸菌因具有促进有氧稳定性、抑制二次发酵、产生抗菌物质、抑制有害微生物等特点已广为应用。纤维素酶制剂添加效果主要受酶本身的特性、青贮原料的特性及青贮时的管理等因素影响,其添加效果尚有待于进一步研究。绿汁发酵液是一种新型的青贮添加剂,具有取材方便、制作简单的特点,可明显改善青贮原料的发酵品质。未来饲草青贮添加剂应用应全面考虑环境要素,加强酶的活性研究,注重多学科综合分析,用纤维素酶与乳酸菌、绿汁发酵液、蔗糖、甲酸等常规青贮添加剂进行复合青贮可能取得进步。 相似文献
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For practical reasons, a large volume (i.e. 5 ml) of frozen boar semen per insemination dose is desirable, but successful freezing has not been achieved, since optimal cooling rates have not yet been established. Post-thaw motility and the acrosome intep'ty of semen from four boars frozen with a programmable freezin machine, in mini-(0.25 ml), maxi-(5 ml) plastic straws and in 10 × 5 cm PVC- or Teflon FEP-plastic bags (0.35 – 0.12 mm thick, 5 ml) was studied. The freezing of the semen was monitored using thermocouples placed in the straws and the bags. The freezing curve started from +5°C, at a rate of −3°C/min, to – 6°C, it was held for 1 min at −6°C, and was followed by further drop to −100°C at a rate of −20°C/min, with subsequent storage in LN2 . The bags had a much shorter freezing point plnteau, compared to the maxi-straws. Post-thaw sperm motility was significantly higher when semen was frozen in mini-straws or in bags than in maxi-straws. The freezing procedure did not cause major acrosomal damages, significantly more normal apical ridges being present in the bags and mini-straws than in the maxi-straws. This in vitro evaluation indicates that the freezing method employed is satisfactory for freezing large volumes of boar semen into plastic bags . 相似文献
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探索经济、高效、无污染的杀死柑桔大实蝇幼虫的科学方法。选择塑料袋加杀虫剂[1] [2]与不加杀虫剂闷处柑桔大实蝇蛆果的方法,得出幼虫死亡数据,并采用方差法比较分析。结果显示,塑料袋封口不加药处理和塑料袋封口加药处理,其幼虫死亡率在5天后无显著差异,且经济无污染。在隔绝空气的条件下更易杀死柑桔大实蝇幼虫。 相似文献
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通过在玉米秸秆青贮中应用添加剂进行调制的实践,总结了实际调制过程中各种常见添加剂的使用方法,同时就应注意的一些问题进行了探讨。 相似文献
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对广益扁穗牛鞭草采用塑料袋进行青贮,通过使用不同厚度(0.6 mm、0.8 mm和1.0 mm)的聚乙烯薄膜和 不同的填装方法(压实和抽气),60 d后对青贮料进行品质鉴定,比较不同厚度薄膜和填装方法的优劣。结果表明,0.6 mm 规格不适于做青贮袋,0.8 mm、1.0 mm规格均适合;就抽气和压实而言,抽气由于工艺相对简单而效果较差,但压实过程 中由于力度难以掌握同样容易使塑料袋破损而导致青贮失败。 相似文献
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幼桑地膜覆盖对桑树生长的效应 总被引:1,自引:0,他引:1
幼桑地复盖地膜表明:桑树发芽早6 ̄10日,发芽率高,除草节本25%,条数,条长明显增加,秋叶亩增160kg,细桑成活率增2.4%。 相似文献