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1.
饲料中黄曲霉毒素(AFB1)容易超标,检出率达80%~100%,毒性大,具强致癌性,可抑制生猪免疫机能,降低动物生产性能,引起动物继发感染,还会在动物产品中残留而威胁人类健康,给生猪养殖带来经济损失,降低猪肉食品安全性。本文通过使用先进固体发酵系统设备和益生菌发酵技术,采用单因素试验和响应面中试优化,获得发酵降解猪饲料AFB1的最佳工艺参数为硒浓度0.3 mg/kg,发酵时间12 h,量子波强度30 Hz,益生菌菌种组合CGMCC NO.17328混合CGMCC NO.15611。该工艺将猪饲料AFB1量从63.41μg/kg降解到2.98μg/kg,降解率达到95.30%,AFB1含量达到国家饲料安全标准。生产工艺适合养猪场低成本快速生产AFB1达标猪饲料。  相似文献   
2.
香菇新菌株宁香8号选育初报   总被引:7,自引:1,他引:6  
采用多孢分离技术产生多个新组合,经驯化筛选获得香菇新菌株宁香8号。宁香8号菌丝生长适温10-25℃,子实体生长适温10-23℃,菌丝生长期58-60d,室内栽培生物学效率达81.60%,室外栽培生物学效率达92.85%,宁香8号不仅适于阔叶木屑栽培,亦适公杉木屑袋栽。  相似文献   
3.
本试验是在PDA培养丛中,添加不同浓度的高美施微肥,通过两个供试菌株的对比试验,选出了适宜各菌抹的最佳高美施生长浓度,结果,不同苗株在不同浓反的高美施培养基中的在现不一致。因此.在制种工作中,要根据平菇不同品种的特征特性来确定其最佳生长的营养条件。高美施在平菇母种制种技术上的应用在国内属首次报道。  相似文献   
4.
Metalaxyl [methyl-N-(2′-methoxyacetyl)-N-(2,6-dimethylphenyl)-d,l- alaninate] is a potent phenylamide fungicide. The (−)-(R)-isomer accounts for most of the fungicidal activity. A possible stereo and/or enantioselective kinetics of metalaxyl in rabbits was investigated by intravenous injection. The concentrations of (−)-(R)- and (+)-(S)-metalaxyl in plasma, liver, and kidney tissue were determined by HPLC with a cellulose-Tris-(3,5-dimethylphenylcarbamate)-based chiral stationary phase and gas chromatography-mass spectroscopy. After intravenous administration of racemic metalaxyl (40 mg/kg), the (+)-(S)-enantiomer levels in plasma, liver, and kidney decreased more rapidly than the (−)-(R)-isomer. The area ratio of the (−)-(R)-/(+)-(S)-enantiomer under the concentration-time curve (AUC0 → ∞) in plasma after drug application was 1.62. The total plasma clearance value of the (+)-(S)-enantiomer was 1.53 and higher than that of the (−)-(R)-enantiomer. The [R]/[S] ratio in plasma was >1 for standard rac-metalaxyl at each time point. The other pharmacokinetic parameters of the enantiomers were also different. The results indicate substantial stereoselectivity in the degradation of metalaxyl enantiomers in rabbits.  相似文献   
5.
反刍动物过瘤胃淀粉研究进展   总被引:4,自引:0,他引:4  
过瘤胃淀粉是高产反刍动物葡萄糖的重要来源之一。本文阐述了过瘤胃淀粉在反刍动物营养中的作用,以及提高饲料过瘤胃淀粉比例的处理方法,并根据近年来的应用研究状况,提出了过瘤胃淀粉在应用中存在的问题及今后的研究方向。  相似文献   
6.
Isoxaflutole is a new pre‐emergence herbicide for use in maize and sugarcane. Its two main derivatives are a diketonitrile derivative, the 2‐cyano‐3‐cyclopropyl‐1‐(2‐methanesulfonyl‐4‐trifluoromethylphenyl)propan‐1,3‐dione, named DKN, and a benzoic acid derivative, the 2‐methanesulfonyl‐4‐trifluoromethylbenzoic acid, named BA. The adsorption/desorption processes have never been studied for isoxaflutole (IFT) at high concentrations nor for BA, and the present work aimed at completing the knowledge of the behaviour of these three molecules in conditions close to those encountered in the context of agricultural use. The adsorption/desorption study was conducted on seven soils of different physical and chemical properties, using the batch equilibrium technique. During the experiments, IFT was chemically converted into DKN in a continuous manner. This reaction appeared to be dependent on the pH of the soil and was taken into account in the calculations of the adsorbed and desorbed amounts. The adsorption isotherms obtained were predominantly C‐shaped for IFT and DKN and S‐shaped for BA, but some differences appeared on a few soils. They fitted well the Freundlich equation, and the values of the Freundlich coefficient Kfa showed that, whatever the soil, IFT was more adsorbed than its two derivatives. The main parameter influencing the adsorption of IFT appeared to be the organic matter content, whereas this effect was not evident for DKN and BA. No correlation was found between the extent of adsorption and either clay content or pH of the soil, for the three molecules.  相似文献   
7.
环境条件和微生物对灭线磷降解的影响   总被引:15,自引:2,他引:15  
环境条件和微生物影响灭线磷在土壤中的降解。随着土壤含水量和温度的增加,灭线磷的降解速度加快;微生物对灭线磷的降解有显著影响,30℃、含水量为40%条件下,未灭菌土中灭线磷的半衰期为16.6 d,灭菌土中灭线磷的半衰期为31.6 d;有机质对灭线磷的降解也有显著影响,有机质含量高,有利于灭线磷的降解;灭线磷在碱性土壤中的降解快于在酸性土壤中;30℃、含水量为40%条件下,灭线磷在3种土壤中的降解速度为:东北黑土>广东红土>山东砂壤土。  相似文献   
8.
干旱区绿洲荒漠交错带土地退化及生态重建   总被引:20,自引:15,他引:20  
由于经济的发展,土地资源受到越来越大的压力。当这种压力超过了土地资源的承载能力,就导致了土地退化的发生。作为陆地生态系统的基础,土地资源的退化表现为:土壤肥力降低,生物多样性降低,以及伴随的经济发展的落后。当前世界范围内对土地退化的治理,基本方法仍是基于生态学理论的生物方法。但对土地退化的恢复与生态系统的重建的研究,需要经过谨慎设计的长期实验。绿洲荒漠交错带的重要性,不仅表现为是绿洲的保护屏障,而且在绿洲经济的发展中也起到巨大的作用。通过对国内外大量研究的回顾,讨论了在不同地区进行的长期实验所采用的方法。有人为因素参与的退化土地恢复与生态重建,可以在短期内取得明显效果。产生土地退化的原因,不仅仅是土地资源特点与自然环境这样一些自然因素,还包括一些社会与经济因素。因此退化土地的恢复与生态重建的成功,需要一种考虑自然、社会和经济因素的综合的方法。  相似文献   
9.
苹果渣发酵料栽培糙皮侧耳优良菌株的选育   总被引:2,自引:0,他引:2  
新选育的糙皮侧耳菌株PL -A2 属于早熟型品种。该菌株菌丝在 5~ 37℃温度范围内均能生长 ,菌丝生长适温为 18~ 30℃ ,最适温度为 2 5~ 2 8℃。在苹果渣发酵料培养基上 ,菌丝粗壮、整齐、洁白 ,爬壁能力强 ,满袋天数为 2 2d± 1d。经推广栽培证明 ,PL -A2 是高产优质菌株  相似文献   
10.
Five soil samples were taken from each of five fields with different crop management histories. Three of the fields were in an arable rotation, the fourth field was temporary grassland, and the final field was under permanent grass. Of the three arable fields, two had been cropped with winter wheat in three of the preceding 6 years, and the third had last been cropped with winter wheat once only, 6 years previously. With one exception, the winter wheat had been sprayed with the herbicide isoproturon. The rate of isoproturon degradation in laboratory incubations was strongly related to the previous management practices. In the five soils from the field that had been treated most regularly with isoproturon in recent years, <2.5% of the initial dose remained after 14 days, indicating considerable enhancement of degradation. In the soils from the field with two applications of the herbicide in the past 6 years, residues after 27 days varied from 5% to 37% of the amount applied. In soils from the other three sites, residue levels were less variable, and were inversely related to microbial biomass. In studies with selected soils from the field that had received three applications of isoproturon in the previous 6 years, kinetics of degradation were not first‐order but were indicative of microbial adaptation, and the average time to 50% loss of the herbicide (DT50) was 7.5 days. In selected soils from the field that had received just one application of isoproturon, degradation followed first‐order kinetics, indicative of cometabolism. Pre‐incubation of isoproturon in soil from the five fields led to significant enhancement of degradation only in the samples from the two fields that had a recent history of isoproturon application.  相似文献   
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