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991.
为了探究适宜香菇L-808秋栽的最佳接种期,开展了不同接种期对香菇L-808栽培的影响试验。结果表明,丽水市9月上旬接种比较适宜,子实体产量最高,不同接种期处理对香菇子实体商品性状的影响不是很大。  相似文献   
992.
为了有效利用我省丰富的油茶蒲资源,缓解近年食用菌栽培原材料上涨压力,研究以油茶蒲部分代替杂木屑栽培高温型香菇,以配方试验方式,探寻利用油茶蒲栽培香菇的配方技术。结果发现,以30%的油茶蒲代替杂木屑栽培香菇是可行的,香菇产量及品质与对照相比无显著差异。  相似文献   
993.
盐碱地水产养殖技术100问(一)   总被引:2,自引:0,他引:2  
王慧 《河北渔业》2006,(2):27-28
我省是一个贫水的省份,内陆养殖用水日趋紧张,但我省的地下半咸水和盐碱荒地资源丰富,开发利用这些资源,将会对我省水产业发展提供更广阔的空间。中国水产科学院东海水产研究所连续几年在沧州市研究利用地下半咸水开发盐碱荒地养虾项目取得了阶段性成果,解决了盐碱荒地利用中的关键技术难题。在此基础上,我省水产部门立项推广该成果。为了配合项目开展,进一步开发利用覆盖沧州、保定、邯郸、衡水、廊坊、唐山的荒废盐碱地资源,促进农民增收和农村经济综合发展,本刊拟连续刊登中国水产科学院东海水产研究所王慧研究员编写的“盐碱地水产养殖技术100问”。希望读者学习并从中受益。  相似文献   
994.
The purposes of this study were to assess the improvement of fatty liver induced by ethanol with animal liver and bile extracts. This research aimed to increase the economic values of animal liver and bile extracts and used these to reduce damage of ethanol‐induced fatty liver. Extracts came from animal liver and bile, including pig bile powder, pig liver extract, a mixture of pig bile powder and pig liver extract, chicken bile powder, chicken liver extract, and a mixture of chicken bile powder and chicken liver extract, and these were fed to Long‐Evans rats. The results showed that rats fed ethanol for long terms could increase values of aspartate transaminase, cholesterol, γ‐glutamy‐transferase and alkaline phosphatase. Pig bile powder could decrease the values of aspartate transaminase, cholesterol and γ‐glutamy‐transferase. The significances also decreased on aspartate transaminase, γ‐glutamy‐transferase and aspartate transaminase, which were carried out with the pig liver extract treatment. These results suggest pig bile and liver extracts have high potential to improve rats' ethanol‐induced fatty liver with serum biochemical parameters.  相似文献   
995.
In order to gain nucleocapsid protein (N) and glycoprotein (E) of porcine reproductive and respiratory syndrome virus (PRRSV), the total RNA was extracted,ORF7 and ORF5 genes were obtained by RT-PCR, inserted into pET-28a(+) vector, and then transformed into Escherichia coli BL21(DE3),respectively. The expressed products were identified by SDS-PAGE and Western blotting, and purified by affinity chromatography. The results showed that N and E fusion protein were successfully expressed and the proteins had good reactionogenicities by Western blotting analysis. The purities of the purified proteins were 89% and 90%, respectively. This study could lay foundations for molecular biological function research and establishment of test methods for detection antibodies of PRRSV.  相似文献   
996.
本试验旨在研究分析市场上正在广泛使用的饲料添加剂,探讨二次饲喂雄性幼犬后饲料添加剂蓄积对其生长、生殖发育的影响研究。选用12只1月龄犬,随机分为试验组和对照组,对照组犬饲喂正常日粮和大鼠鼠肉,试验组犬饲喂正常日粮和高剂量组大鼠鼠肉,喂养幼犬直至成熟,检测食用饲料添加剂高剂量组大鼠鼠肉是否对雄性犬的生长、生殖发育产生影响。采用酶联免疫试剂盒的方法来检测犬血清激素指标水平。结果显示:试验组雌二醇、促卵泡激素含量明显升高(P<0.01),而睾酮含量明显降低,有显著性差异(P<0.01),饲料添加剂高剂量组对犬血清中的促黄体生成未见显著变化。雄性幼犬食用试验大鼠后可导致雄性幼犬青春期体内内分泌激素含量异常,即青春期11月龄测定的雌二醇以及促卵泡激素水平增高,睾酮的水平降低。提示试验组雄性幼犬食用大鼠鼠肉后,可能通过干扰了睾丸轴的功能,对雄性幼犬的生殖发育能力产生影响。  相似文献   
997.
The highly polymorphic genes within the major histocompatibility complex (MHC) not only play a major role in immunity resistance, but also seem to provide hints for mate choice in some animal populations. In the present study we investigated MHC‐related mate choice in a small natural population (group size 40–55 individuals) of a polygynous primate, the Sichuan snub‐nosed monkey (Rhinopithecus roxellana). We found that there was no evidence either for MHC‐disassortative mating, or for females to mate with males based on MHC heterozygosity or specific alleles. Nevertheless, of the 11 alleles identified, we found that the frequencies of 2 alleles, Rhro‐DRB2 (P < 0.01) and Rhro‐DRB5 (P < 0.05) were higher in offspring than in their parents. These findings suggest that MHC‐DRB in this population of R. roxellana is unlikely to be associated with mating preferences. Limited female opportunities for mate choice are likely due, in part, to the harem breeding structure present in R. roxellana, and the relatively small number of resident adult males in our study band (N = 4–6). In addition, we suggest that differences in the frequency of particular alleles across generations may be linked to parasite resistance in a fluctuating environment; however, confirmation of this finding requires further study.  相似文献   
998.
柘林湾网箱养殖海域溶解氧分布及其影响因素   总被引:5,自引:0,他引:5  
根据1998年7月在南海东北部柘林湾的调查数据,探讨网箱养殖海域溶解氧的分布及其与其他环境因子间的关系,结果显示夏季海水溶解氧浓度为3.03-7.86mg/L( 平均5.30),退潮时(平均5.71)高于涨潮时(平均4.65)涨潮时网箱区内贫氧( <0.mg/L).多元逐步回归分析表明,对溶解氧浓度有重要影响的水质因子为pH和水温,其次为盐度,COD和营养盐,它们的变化与DO的变化有较好的相关性,区域比较表明,海水溶解氧浓度与观测僧置到网箱区的距离呈正相关(P<0.02),与底质硫物,PO4-P含量呈负相关(P<0.05),溶解氧浓度偏低与养殖环境的污染有直接关系。  相似文献   
999.
中国对虾往西北内陆咸水水域移植的生产性试养研究   总被引:8,自引:1,他引:8  
王慧  田荣庆 《海洋渔业》1997,19(1):9-12
本文介绍了通过采用引进河水、压碱降盐等改良水质的技术措施,使中国对虾首次成功地移植到内陆咸水水域。经过1个月的试养,中国对虾平均体长增长3.82 cm,平均体重为1.82 g。  相似文献   
1000.
Abstract. Groups of channel catfish, Ictalurus punctatus (Rafinesque). were administered Edwardsiella ictaluri twice in the form of whole outer membrane proteins (OMP) or heat-inactivated whole bacteria (IWB) orally or IWB intraperitoneally. Antibody titres and lysozyme concentrations were determined in serum, mucus, gut contents and gut washings taken 7, 14, 21 and 28 days after the second antigen administration. Bacterial killing by anterior kidney neutrophils was determined 7, 14 and 21 days after the second antigen administration. Enhanced killing of tumour targets by nonspecific cytotoxic cells (NCC) was determined 7 days after the second antigen administration. Serum antibody titres of all treatment groups were significantly increased above those of the control group throughout all sampling periods. Fish receiving oral administration of OMP or IWB exhibited maximum serum antibody titres on day 21 or 28. Antibody titres were also detected in mucus, gut washings and gut contents, but did not reach the level of those in the serum. Bacterial killing was significantly increased only on day 7, and could not be correlated to antibody titre or lysozyme concentration. Bacterial killing was found to be the result of a heat-labile serum factor. NCC activity of fish vaccinated with IWB orally was significantly higher than that of fish vaccinated with OMP orally or controls. Although intraperitoneal vaccination consistently produces higher titre antisera, the results of this study support the idea that oral vaccination can induce antibody systhesis.  相似文献   
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