应用纤维素酶评定粗饲料的消化率

以两阶段法为基础,研究了两种酶解法对12种粗饲料的消化情况,结果表明:(1)中性洗涤剂+纤维素酶法的测值与两阶段法所测消化率之间虽相关显著(P<0.01),但方程的离回归标准误转大,预测值的变异系数也较大(对青干牧草、枯草和秸秆以及将三者组合统计时,变异系数分别为18.35％,7.29％,33.66％),说明应用此法估计消比率的可靠性较差;(2)以纤维素酶+胃蛋白酶法估计消化率较为可靠。该法的测值与两阶段法显著相关(P<0.01),离回归的标准误也小,估计值的变异系数对青干草、枯草和秸秆分别统计时,仅12.37％和8.36％。     

A method for the attachment of miniature radio tags to small fish

Abstract An attachment technique which gives good tag retention, minimal damage to fish and prevents entanglement with weed is described. Fish carrying transmitters were monitored in semi-natural conditions and appeared to exhibit the same behaviour as untagged fish. Median condition factors of dummy-tagged fish did not differ from those of untagged fish over a 10-week period. Examples of movement patterns obtained using radio tags attached to dace, Leuciscus leuciscus (L.) are given.     

Indentification of true genetic dwarfing sources in foxtail millet (Setaria italica Beauv.)

Summary True genetic dwarfs hither-to not reported have been located in foxtail millet. The dwarfs as a group distinguished themselves from the talls in having altered constellation of characters. The morphological differences were highly significant for plant height, internodal length, and tillering potential. The talls had elongated internodes compared to dwarfs while there was no difference for node number on the main stem suggesting that short internodal length was primarily responsible for dwarfism. The dwarfs also showed slightly higher leaf number per plant, leaf area and harvest index compared to talls. The dwarfs were insensitive to exogenous GA₃ application indicating that GA₃ synthesis is not impaired. This suggests that dwarfing gene sources presently identified are true genetic dwarfs and their behaviour is similar to dwarfs derived from Norin 10 in wheat and Dee-geo-woo-gen in rice. The superior morphological frame makes these dwarfs ideal as far as plant type is concerned and offers immense potentialities in breeding high yielding foxtail millets.     

不同浓度盐胁迫对转基因饲用甜菜种子萌发及幼苗生长的影响

通过不同浓度NaCl溶液处理转基因饲用甜菜种子及其幼苗试验，研究了盐胁迫下种子萌发、幼苗生长及胁迫解除后种子的效应，为盐土农业生产提供理论依据。结果表明，转基因饲用甜菜种子萌发的适宜Nacl浓度为50。150mmol/L，其中100mmoL／LNaCl胁迫下，种子发芽率最高，与对照相比高6．78％。随着盐胁迫浓度的升高，种子萌发延迟，萌发率也呈不同程度的降低。盐胁迫解除后，种子萌芽迅速，萌芽率提高，整齐度增加。转基因饲用甜菜幼苗在不同NaCl浓度胁迫下表现出的反应不同，高盐胁迫对抑制幼根生长影响较大。     

森林粗木质残体的贮量和碳库及其影响因素

粗木质残体(CWD)是森林生态系统重要的组成要素,由于定量研究某特定区域CWD的贮量和碳量的工作量相当大,需要长期的研究才能获得可信的数据,因此有关全球森林生态系统CWD的贮量和碳量仍不太清楚.本文根据国内外研究结果综述全球不同森林中CWD的贮量和碳库情况.结果表明:温带针叶林CWD贮量最高(30～200 t·hm-2),而阔叶林最低(8～50 t·hm-2);全球森林CWD碳贮量范围大致为75～114或157 Pg.各森林CWD贮量值变化大,因林龄、CWD分解阶段和人类经营活动(如疏伐、皆伐和控制火烧)而异.今后需更广泛地开展森林CWD调查,以更深刻理解CWD与林分结构、树种特性及干扰的关系.此外,为了更准确地评价CWD在森林生态系统中的生态价值,建议在更大尺度上对全球各类森林的CWD贮量和碳库进行长期的研究.     

用边际分析法确定黄河中游粗泥沙集中来源区

 为进一步寻找并治理对黄河下游主槽淤积危害最严重的粗泥沙集中来源区,根据1960年未建三门峡水库前自然水沙条件下下游河槽淤积物粒径组成,确定出黄河中游粗泥沙集中来源区界定中的粗泥沙界限为0.1mm。利用边际分析法在黄河中游多沙粗沙区确定粗泥沙集中来源区面积为1.88万km2。该面积仅占黄河中游多沙粗沙区面积的23.9%,可产生的全沙、粒径大于0.05mm和0.1 mm的泥沙分别占同期多沙粗沙区相应沙量的34.5%、47.6%和68.5%。由此看出,该区是名副其实的粗泥沙集中来源区。     

羽毛蛋白粉高效利用研究

采用物理加工与生物加工结合的方法，即先超微粉碎至微米级后再用解朊酶进行体外水解处理的方法对羽毛粉进行饲料化研究，通过研究发现经处理的羽毛粉比对照组（未经处理过的羽毛粉）的可溶性蛋白质含量和溶解度分别比原来增加了3.37倍和3.38倍，胃蛋白酶消化率提高了15%，表明此加工工艺可大大提高羽毛粉的生物学效价。     

EM发酵饲料喂猪增重试验研究

EM(有效微生物群)是一种新型复合型微生物制剂,无毒害、无残留、不污染环境。经用A、B两种饲料以EM发酵处理后喂猪试验结果,增重显著地高于对照组,料肉比明显降低(经EM发酵处理后的A料料肉比由原来的4.87∶1降低到4.28∶1;B料由原来的4.23∶1降低到4.03∶1),且经济效益显著提高。试验证明,应用EM发酵饲料喂猪,不仅明显降低养猪成本,提高饲料报酬,而且增强机体抗病力,促进猪的生长。为加快养猪业的发展,建议我各猪场、养猪专业户大力推广EM生物技术。