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91.
我国主要粮食品种供给与消费平衡分析   总被引:11,自引:1,他引:11  
论文基于城市和农村人口及其人均食物消费、粮食工业产品产量、肉蛋奶水产品产量、单位面积种子用量等估算了2013年我国主要粮食品种实际消费量和合理膳食结构下的理想消费量。研究结果显示:我国稻谷、玉米、小麦和薯类以国内生产为主,大豆主要依赖进口;我国稻谷和小麦以口粮消费为主,玉米和豆类以饲料用粮消费为主,薯类以工业用粮和饲料用粮消费为主;稻谷、小麦、玉米和薯类结余量较大,豆类结余量少;按照现有的饮食结构,只需要71%的稻谷生产量和52%的小麦生产量就能完全满足口粮需求。未来应关注稻谷和小麦口粮生产,实施全过程监管以及资金和技术支持,其他用途或品种的粮食生产应由市场主导。  相似文献   
92.
Feed security is a prerequisite for safe animal food products. In this study, 13 groups of feed and feed ingredients, totaling 2067 samples, were collected in the period of 2011 to 2014 from China. The highest mean level of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) was found in fish meals and shell powders, with a concentration of 60.35 ng/kg, followed by mineral origin materials. In terms of the toxicity equivalent concentration, the fish oil group showed the highest PCDD/F levels because of their bio-accumulation through the aquatic food chain, with an average concentration of 1.26 ng WHO-TEQ/kg, while the lowest level was observed in compound feed for chickens and pigs, with an average value of 0.16 ng WHO-TEQ/kg. OCDD and OCDF were the predominant congeners in all groups except fish oils, in which the primary congeners were 2,3,4,7,8-PeCDF and 2,3,7,8-TCDF. For zinc chloride samples, different from other zinc-based compound samples, the main congeners were 1,2,3,4,6,7,8-HpCDF (17%), 1,2,3,4,7,8,9-HpCDF (15%), 1,2,3,4,7,8-HxCDF (12%) and OCDF (30%). Considering toxicity equivalency factors, the dominant congeners were 2,3,4,7,8-PeCDF, 1, 2,3,4,7,8-HxCDF, 2,3,7,8-TCDF and 1,2,3,7,8-PeCDD, and the contribution to the total TEQ was 29%, 16%, 14% and 12%, respectively. Overall, 2.1% (43 out of 2067) of all the analyzed samples exceeded the different individual ''European Union maximum limited levels for PCDD/Fs. This study is beneficial for the determination of the status of contamination levels of feed and feed ingredients.  相似文献   
93.
Jatropha seed cake contains high amounts of protein and other nutrients, however it has a drawback due to toxic compounds. The aim of this study was to investigate the methods applied to detoxify the main toxin, phorbol esters in jatropha seed cake, to a safe and acceptable level by maintaining the nutritional values. Phorbol esters are tetracyclic diterpenoids-polycyclic compounds that are known as tumor promoters and hence exhibited the toxicity within a broad range of species. Mismanagement of the jatropha waste from jatropha oil industries would lead to contamination of the environment, affecting living organisms and human health through the food chain, so several methods were tested for reducing the toxicity of the seed cake. The results from this investigation showed that heat treatments at either 120°C or 220°C for 1 hour and then mixing with adsorbing bentonite (10%), nanoparticles of zinc oxide (100 μg/g) plus NaHCO3 at 4%, followed by a 4-week incubation period yielded the best final product. The remaining phorbol esters concentration (0.05–0.04 mg/g) from this treatment was less than that reported for the nontoxic jatropha varieties (0.11–0.27 mg/g). Nutritional values of the seed cake after treatment remained at the same levels found in the control group and these values were crude protein (20.47–21.40 + 0.17–0.25%), crude lipid (14.27–14.68 + 0.13–0.14%) and crude fiber (27.33–29.67 + 0.58%). A cytotoxicity test conducted using L929 and normal human dermal fibroblast cell lines confirmed that most of the toxic compounds, especially phorbol esters, were shown as completely eliminated. The results suggested that the detoxification of phorbol esters residues in the jatropha seed cake was possible while it also retained nutritional values. Therefore, the methods to detoxify phorbol esters are necessary to minimize the toxicity of jatropha seed cake. Further, it is essential to reduce the possible environmental impacts that may be generated throughout the jatropha waste-handling process. However additional tests such as digestibility as well as acceptability of the treated jatropha seed cake should be conducted using both in vivo and in vitro studies before recommending the jatropha seed cake as a source of renewable animal feed and other value-added products.  相似文献   
94.
Existing evidence indicated that dichlorodiphenyltrichloroethane (DDT)-containing antifouling paints were an important source of DDT residues to mariculture zones. However, the magnitude of the impact on aquafarming environment has remained largely unknown. In the present study, the concentrations of DDT and its metabolites (designated as DDXs) were determined in harbor sediment and antifouling paint samples collected from a typical mariculture zone in South China. Compositional and concentration correlation analyses implicated the DDT-containing antifouling paints for fishing boat maintenance as an important source of DDT in the mariculture zone. The annual emission of DDXs to the study region was estimated at 0.58 tons/yr. Furthermore, a comparison of the expected DDT loadings in pelagic fish and field measurements indicated that fish feed especially trash fish was a major source of DDTs in the fish body. Nevertheless, the use of DDT-containing antifouling paints should be limited to prevent further deterioration in aquafarming environment.  相似文献   
95.
铬革渣资源化处理研究Ⅷ--饲料胶原蛋白粉的毒理试验   总被引:1,自引:0,他引:1  
饲料胶原蛋白粉的LD50>10g/kg,属实际无毒级;蓄积系数K>5.28,属弱蓄积性;Ames不论加S-9混合液与否,致突变作用结果为阴性;微核试验剂量高达5g/kg仍为阴性;精子畸形试验剂量5g/kg亦呈阴性。  相似文献   
96.
在上海市郊区选取5个大型养殖场,分别采集地表水、饲料、土壤及蔬菜样品,对其进行总砷及无机砷含量调查,以了解目前上海市郊区养殖场砷含量水平特征,以及有机胂饲料添加剂的使用情况.结果表明,水样中总砷含量介于0.00~23.00μg·L-1之间,低于国家规定的地表水环境质量一级标准(50μg·L-1);饲料中总砷含量在0.40~12.13 mg·kg-1之间,其中无机砷占总砷的10.0%~80.0%;抽查饲料样品中总砷含量范围为0.16~21.39 mg·kg-1,无机砷含量在0.003~10.67mg·kg-1之间,其中超过饲料中砷的限量标准的占16.7%;土壤中总砷含量介于8.08~18.50 mg·kg-1,22.2%的土壤样品中总砷含量超过土壤环境质量一级标准,土壤中无机砷占总砷44.2%~78.9%;蔬菜中总砷含量在0.003~0.093 mg·kg-1之间,均低于国家规定的限量标准0.50 mg·kg-1;同种蔬菜不同部位砷含量存在一定差异:根部含砷量要高于地上部分,蔬菜中总砷富集系数与总砷含量呈明显的正相关,与根际土壤中砷含量呈一定的负相关.  相似文献   
97.
Abad E  Llerena JJ  Sauló J  Caixach J  Rivera J 《Chemosphere》2002,46(9-10):1417-1421
Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in some additives widely employed as binder and anti-caking agents in feedstuffs, such as kaolin, bentonite, zeolite, etc. with an special attention on sepiolite samples. Owing to their physico-chemical properties, the little information of these materials reported in the literature, the variability of PCDDs/PCDFs found in a preliminary evaluation and the absence of reference materials highlighted further research needed. Therefore, an extensive study on the analytical procedures based on the classical methods was performed with sepiolite samples. The study includes evaluation of reproducibility and repeatibility. To this end, a series of intra-day and nine inter-day analysis were made. The methodolgy was also assessed against the sample size and series of 12.5, 25, 37.5 and 50 g were analyzed. In all cases, the results confirmed good correlation with the parameters evaluated.  相似文献   
98.
The effect of either boron (B) or molybdenum (Mo) on survival, growth and feed intake of Indian major carp, Cirrhinus mrigala (Hamilton), advanced fry was studied in two separate experiments. Survival rates of C. mrigala fry (2.78±0.14 g) following 50 days’ exposure to B at 0.01 (control), 0.5, 1.0, 2.0, 4.0 and 8.0 mg·L ?1 were 100% at all concentrations except 8.0 mg·L ?1 where the survival rate 87.5±7.5%. We observed 100% survival of mrigala fry at all concentrations of Mo, 0.02 (control), 0.5, 1.0, 2.0, 4.0 and 8.0 mg·L ?1. Both B and Mo at 0.5 mg·L ?1 showed significantly (p<0.05) higher growth of the fish compared with control and other concentrations. B exposure at 1.0, 2.0 and 4.0 mg·L ?1 had no significant effect on growth rate, whereas at 8.0 mg B·L ?1 growth of the fish almost ceased. Mo exposure at 1.0, 2.0, 4.0 and 8.0 mg·L ?1 caused no significant effect on growth rate of the fish compared to control. Both B and Mo at all concentrations had no significant effect on feed intake of the fish compared with control, except at the highest concentration of boron (8.0 mg·L ?1).  相似文献   
99.
We applied pyrosequencing to determine bacterial communities in soil samples taken from test fields amended by manures of pigs fed with green feeds (GPMS), synthetic feeds (APMS), and the reference field without swine manure amendment (NPMS), respectively. For each sample, 7050 effective sequences were selected and utilized to do the bacterial diversity and abundance analysis, respectively. In total, 2986, 2873, and 1602 operational taxonomic units were obtained at a 3% distance cut-off in GPMS, APMS, and NPMS, respectively. Bacterial phylotype richness in GPMS was higher than the other samples. NPMS had the least richness. The most dominant class in both GPMS and APMS is Betaproteobacteria, whereas Alphaproteobacteria is dominant in NPMS. Circa 7.5% sequences in GPMS were found to be affiliated with Burkholderiales order. Bacterial diversity and abundance in the soil varied with swine manure amendment, due to nutrient elements as well as toxic metals in swine manures. Compared with the soil amendment by manures from pigs bred with synthetic feeds, more bacterial diversity but less potentially pathogenic bacterial genera in the soil amended by manures of pigs fed with green feeds were found, which indicated that these manures were better land-applied organic fertilizers.  相似文献   
100.
洞庭湖区芦苇和荻的饲用潜力及开发利用   总被引:11,自引:0,他引:11  
洞庭湖区拥有丰富的芦苇和荻资源。两者鲜嫩时的化学与营养成分接近优良牧草黑麦草,适于饲喂牛。若于拨节中期收获2~4次,则可年产干草4.5~7.5×105t,可为8.22~20.55×104个黄牛单位提供全年用优质饲草;若再与湖区丰富的农副产品相配合,发展集约化商品性的养牛业是切实可行的。收获的牧草可通过青饲、青贮、调制干草、加工成草粉或颗粒配方饲料的方式加以利用。为保障秋季其他用途的收获及第二年的正常生长发育,必须要采取一系列行之有效的措施,其中人工促进再生复壮和加强宏观调控是最关键的环节。  相似文献   
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