论鄂尔多斯东北部的资源开发与环境整治   总被引：3，自引：0，他引：3  

郭绍礼 《干旱区资源与环境》1994,8(1):29-43

本文是从资源开发条件的评价入手，揭示所出现的环境问题，并提出建立人工高效开发－整治型的综合模式结构，以便持续稳定地协调好资源开发与环境整治的关系，促进这里的经济发展。  相似文献   

新疆山区降水资源及其开发利用     

邓子风  张英 《干旱区资源与环境》1992,6(4):19-24

本文论述了新疆山区的降水特征及其空间与时间上的分布规律,提出了合理利用降水资源的意见。  相似文献   

黄河大柳树灌区土壤类型特征与合理开发途径     

梅成瑞  魏光智 《干旱区资源与环境》1992,6(4):79-88

该文分析了黄河大柳树灌区土壤类型形成条件与分布格局和主要土壤类型的基本特征,在此基础上结合发展灌溉农业对土壤条件的要求,提出土壤资源合理利用与发展灌溉农业的有关问题。  相似文献   

甘肃省泾川县三元杂交肉牛生长发育的研究报告   总被引：1，自引：1，他引：0  

王德春  胡拴祥  董格平  王宗德 《中国牛业科学》2003,29(1):30-39

本研究测定并对比研究了德秦黄、德利黄、德西黄、利西黄、利秦黄等三元杂交牛及二元杂交牛初生 ,3月龄、6月龄、1 2月龄、1 8月龄的生长发育指标 ,结果表明 :三元杂交牛比二次杂交牛体尺、体重均有较大幅度的增长、初步筛选出适宜泾川养殖习惯的较佳杂交组合。在农户饲养条件下 ,三元杂交初生重 38kg,比二元杂交牛提高 1 2 .8%～ 5 6.6% ;1 8月龄母牛体重 377.8kg,提高 1 5 .2 %～94.1 % ;1日龄～ 1 8月龄日增重 5 2 8.2 g,增长 9.2 %～ 68.7% ;管围提高幅度为 2 4 .1 %～ 32 .3% ;臀围为 1 .7%～ 32 .3% ;体高为 2 .9%～ 1 5 3% ,体斜长为 5 .5 %～ 1 3.9% ,胸围为 1 1 .4%～ 2 0 .5 %。尻长为 5 .1 %～ 1 1 .8% ,腰角宽为 0～ 2 1 .4% ,髋宽为 0～ 3%。适宜的杂交组合为德秦黄、德利黄、德西黄。三元杂交牛 6～ 1 2月龄生长发育受阻 ,主要是饲料营养水平低所致 ,建议从 2月龄开始用优质饲草和配和配合饲料 ,1 8月龄体重达到 40 0 kg以上 ,再经 3个月育肥 ,2 1月龄达到体重 5 0 0 kg的出栏标准。  相似文献   

Bacterial colonization affects early organ and gastrointestinal growth in the neonate   总被引：1，自引：0，他引：1  

R.H. Siggers  T. Thymann  J.L. Siggers  M. Schmidt  A.K. Hansen  P.T Sangild   《Livestock Science》2007,109(1-3):14-18

Enteral nutrition coupled with bacterial colonization has been shown to have major functional and developmental effects during the postnatal period of neonates. In this study, we developed a highly sensitive premature pig model to elucidate the specific developmental impact of initial bacterial colonization on premature neonates by comparing germ-free and conventionally reared pigs. Thirty-eight preterm pigs (93% gestation) were delivered via caesarean section and reared in either germ-free or conventional isolators for 40–48 h. Pigs were fed either infant milk formula or sow's colostrum. Enteral feeding for two days had trophic effects on gastrointestinal weights, particularly for pancreas, stomach and small intestine (SI). The absence of bacteria in formula fed pigs resulted in a mucosa that appeared more robust and had higher weights for both SI and pancreas, compared to conventional formula fed pigs (P < 0.05). Colostrum fed pigs also had markedly increased mucosal SI proportions, lung and spleen weights compared to conventional formula fed pigs. Colostrum fed pigs and germ-free pigs were similar although stomach, pancreas and distal SI weights were highest for germ-free pigs. The results demonstrate that the initial bacterial colonization interacts with diet to modulate the early neonatal organ development, particularly of the GIT.  相似文献   

湟中县发展草地畜牧业的探讨     

陈永尧 《四川草原》2006,(2):55-56,60

湟中县草原面积占土地总面积的60％,适宜发展草地畜牧业。本文试对湟中县发展草地畜牧业存在的问题及措施进行探讨。  相似文献   

伊犁州直奶业发展现状及其对策     

木拉提汗  娜孜拉  巴登加甫  乃比江  王健 《中国牛业科学》2006,32(5):69-71,77

伊犁州直是新疆重要的畜牧业生产基地，奶业发展具有一定优势，但同时也存在不少问题和困难。本文综合阐述了近几年伊犁州直奶业发展现状，通过分析奶业发展的优势、不足及存在的问题，提出了今后的发展方向和对策。  相似文献   

Effects of pyriproxyfen, a juvenile hormone analog, on development of the mealworm, Tenebrio molitor     

N. Aribi  S. Lakbar  N. Soltani 《Pesticide biochemistry and physiology》2006,84(1):55-62

Pyriproxyfen, an analog of the juvenile hormone (JH) in insects, has been evaluated in vivo and in vitro on an important stored product pest, the mealworm Tenebrio molitor. On newly ecdysed pupae, this insect growth regulator (IGR) was applied topically (at 0.10 and 0.20 μg/insect). Enzyme immunoassay measurements showed a decrease of the ecdysteroid titer in the hemolymph of treated specimens. In addition, the treatment induced an increase of the protein concentration in the hemolymph, however, there was no significant effect on the protein band pattern. Using in vitro pupal integument explant cultures, pyriproxyfen (at 1 and 10 μM in the medium) caused a significant inhibition of ecdysteroid amounts and of the thickness of new cuticle secreted. These new results are discussed in relation to the physiology of this IGR with a JH action.  相似文献   

花烛体细胞胚胎发生及植株再生研究     

辛伟杰  徐彬  王广东  郭维明  文方德  金剑平 《园艺学报》2006,33(6):1281-1286

 以花烛(Anthurium andraeanum Lind. ) 盆花品种无菌苗叶片、叶柄、根段为外植体, 对花烛体细胞胚胎发生及植株再生进行了研究, 建立了花烛体细胞胚胎发生体系。结果表明, 花烛叶片较其他外植体更适宜体细胞胚的诱导; 胚性愈伤组织及胚性结构诱导最适培养基为改良MS + 2, 4-D 2.0～3.0 mg·L ^{- 1} + KT 0.5 mg·L ^{- 1} +蔗糖2% +葡萄糖1% , pH 5.5, 暗培养40 d, 诱导率可达90.3%; 体胚发育适宜培养基为改良MS + 6-BA 0.5 mg·L ^{- 1} +蔗糖3% , 光强20 μmol·m ^-2 · s^-1 , 培养20 d后体胚萌发率达6219%; 萌发的体胚在发育培养基上继续培养30 d后均能发育成完整植株。对不同阶段培养材料的组织结构及超微结构的观察证明了花烛体胚发生过程。  相似文献   

比哈小爪螨在3种南方果树上的发育与繁殖   总被引：4，自引：1，他引：4  

张方平  符悦冠  金启安  张敬宝 《果树学报》2007,24(2):185-188

为了探明比哈小爪螨在龙眼、荔枝、杧果上的种群增长情况,采用以上3种果树叶片为寄主材料进行饲养,以观察其发育、存活及繁殖。结果表明,比哈小爪螨取食龙眼世代发育历期最短为14.57d,取食杧果最长为20.71d;世代存活率龙眼最高为93.8%,荔枝最低为83.8%;产卵量以龙眼最高为46.63粒,杧果最低7.32粒;内禀增长率以龙眼最大为0.1328,杧果最小为0.0467;种群趋势指数的顺序为:龙眼>荔枝>果。  相似文献