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941.
利用来自不同地域的淡紫拟青霉的13个菌株,分别用其孢子液处理南方根结线虫分散卵粒、菌丝处理分散卵粒、孢子液处理卵囊以评价淡紫拟青霉对南方根结线虫的寄生性。在被试所有菌株中,同一菌株三种不同方法对根结线虫卵的寄生率相比,孢子液处理卵囊均明显高于其他两种处理。不同菌株对南方根结线虫卵的寄生率有很大的差异。三种处理方法结果显示618号菌株寄生率均为最高。菌株对卵的寄生率与菌株地理来源无明显相关性。 相似文献
942.
中国加入世界贸易组织后,将失去关税保护措施,森工企业应充分利用好过渡期以及世贸组织规则保护发展自己,进一步加快改革和科技创新步伐,努力提高利用外资的水平,尽快适应世贸组织的要求,努力发展壮大自己。 相似文献
943.
944.
巴黎翠凤蝶在甘肃白水江自然保护区1年2代,以蛹越冬,翌年3月下旬越冬蛹开始羽化,4月下旬至5月初为第1代成虫羽化高峰期,第2代成虫羽化高峰期在6月底7月初;寄主为芸香科的飞龙掌血、柑橘类等植物;成虫喜访白色系的花,也好在臭水沟处群聚嬉戏,一般在常绿林带的高处活动,飞行迅速,警觉性高而且很少停息,难以捕捉。红基美凤蝶在白水江自然保护区1年2代,以蛹越冬,翌年4月初越冬蛹开始羽化,4月下旬为第1代成虫羽化高峰期,6月底7月上旬为第2代成虫羽化高峰期;7月下旬成虫数量减少,但直至9月仍可见到成虫;7月上旬产卵高峰期,9月初为化蛹高峰期;直到10月上中旬还可见幼虫;幼虫5龄,历期25~35d;寄主为柑桔等芸香科植物。 相似文献
945.
以女儿寨小流域为研究对象,着重研究了植被恢复重建过程中小流域系统的小气候变化特征。随着小流域内的植被恢复与重建,小流域内最高气温约降低了1~4℃,尤其以夏、秋季更为突出,约降低了3~4℃;最低气温提高了1~2℃,夏季较其它季节更为显著一些;森林不能降低小流域的日平均气温,但能略微增加秋冬季的平均气温0.1~0.5℃;平均地面温度降低了0.9~1.3℃,秋冬季的地面平均温度略微增加0.1~0.5℃;年降水量增加了77~115mm;年蒸发量降低105~175mm。小流域小气候环境发生了较大的变化,小气候质量在不断的提高。 相似文献
946.
该调研对90 kg级大花白肥猪胴体作了切块分析。其大排切块中眼肌相对硕大,有瞬间彩虹折射,系水力强,肌肉组织的弹性良好,切块肥膘洁白无瑕,皮下脂肪肥厚而且饱满坚实,皮层洁白丰厚,无皮下疵瑕。其前肩切块、小排切块、五花肉切块、股二头肌切块肉色鲜艳亮丽,大理石纹丰富细致精美。其股四头肌的红度极高,值得一提。其胴体表现出相当程度的华中型流线型特点,而切块表现出明显的华南型肥满特点,从而表现出华中型与华南型猪肉品质的交混特点,该品种具备传统极品鲜肉和BBQ烧烤肉优势并具备竞争国际品牌猪肉的潜力。 相似文献
947.
DMRT基因家族是一个与性别决定相关的发育基因家族。以鸡、鹌鹑及其属间杂交种胚胎为试验对象,分别采集孵化72 h的鸡、鹌鹑和杂交种胚胎,以DMRT1b为目的基因进行扩增,对DMRT1b基因原序列、扩增序列分析,应用Ex PASy网站对序列编码蛋白进行蛋白质生物信息学分析,结果发现杂交种DMRT1b基因较其父母本发生部分碱基缺失,预测蛋白质功能存在差异,推测由于基因缺失导致蛋白质不同,这种现象可能与杂交种早期死亡、不育存在相关性。研究结果为鸡与鹌鹑属间杂交种雌性致死与雄性不育的研究奠定基础。 相似文献
948.
949.
This experiment was conducted to study the effects of different levels of compound Chinese medicine on growth performance,nutrients apparent digestibility,immune function and slaughter performance of weaning Rex rabbits.70 healthy Rex rabbits at age of 60 days were divided into 7 groups with 5 replicates per group and 2 rabbits per replicate.Group Ⅰ was fed with basic diet as control group,group Ⅱ was fed the basal diet supplemented with antibiotic (contains 50 mg/kg milligrams bacitracin zinc,10 mg/kg colistin sulfate).The other five groups (Ⅲ,Ⅳ,Ⅴ,Ⅵ and Ⅶ) were fed the basal diet supplemented with 1%,2%,3%,4%,5% compound Chinese medicine,respectively.The pre-test period lasted for 7 days and the trial period lasted for 45 days.The results showed as follows:①The ADG in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ and Ⅲ (P< 0.05),the F/G in group Ⅳ was significantly lower than that in other groups (P< 0.05).②The apparent digestibility of DM in group Ⅳ was significantly higher than that in groups Ⅰand Ⅱ (P< 0.05),the apparent digestibility of DM in group Ⅶ was significantly higher than that in group Ⅰ (P< 0.05).The apparent digestibility of CF in group Ⅳ was extremely significantly higher than that in group Ⅰ (P< 0.01),the apparent digestibility of CF in group Ⅶ was significantly higher than that in group Ⅰ (P< 0.05).The apparent digestibility of NDF in group Ⅳ was extremely significantly higher than that in group Ⅰ (P< 0.01),and significantly higher than that in groups Ⅱ,Ⅲ,Ⅴ and Ⅶ (P< 0.05).The apparent digestibility of ADF in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ,Ⅴ and Ⅶ (P< 0.05).The apparent digestibility of CP in group Ⅳ was significantly higher than that in groups Ⅰ and Ⅱ (P< 0.05).③ There were no significant differences in the contents of IgG,IgA and IgM of serum among all groups (P> 0.05),the spleen index in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ,Ⅲ and Ⅴ (P< 0.05).④There were no significant differences in the slaughter rate,half eviscerated slaughter rate and all eviscerated slaughter rate among all groups (P> 0.05).In summary,adding compound Chinese medicine and antibiotics in the feed both could improve the growth performance,nutrients apparent digestibility,immune function and slaughter performance of weaning Rex rabbits,and the appropriate compound Chinese medicine level in the diet of weaning Rex rabbits was 2%. 相似文献
950.
PENG Xiao-bing TIAN Dong-qing LI Xu-ni PENG Guo-rui WANG Meng JIANG Yu-wen 《中国畜牧兽医》2015,42(8):1950-1955
One pair of primers had been designed and synthesized based on the α-toxin gene of Clostridium perfringens.The complete α-toxin gene fragment was amplified by polymerase chain reaction (PCR), and then was cloned into pGEM-T Easy vector to construct pGEM-T-α.Digested with EcoRⅠ and Hind Ⅲ, a fragment of 1125 bp was cloned into the expression plasmid vector pET-28a(+).The recombinant plasmid was transformed into the BL21(DE3)plys and induced by 1.0 mmol/L IPTG at 37 ℃.The expression product was found to be 46.1 ku as expected one identified by SDS-PAGE, and confirmed by Western blotting with Clostridium perfringens type A antisera, indicating similar reactivity with native α-toxin.Recombinant α-toxin protein was simultaneously found in culture supernatant, postsonic supertanant and inclusion bodies, most protein was expressed in inclusion bodies, which indicated recombinant α-toxin protein was expressed in the extracellular, periplasm and cytoplasm.Recombinant α-toxin protein in postsonic supertanant could not make mice die, indicating its non-toxicity.Toxin-antitoxin neutralization test showed that antisera of recombinant α-toxin protein were specific to α-toxin.Upon immunization of rabbit with the recombinant α-toxin protein, antisera with high antibody titer neutralizing 100 MLD toxin per 1 mL were prepared. 相似文献