近30年来中国农作物秸秆资源量的时空分布

【目的】分析1978-2009年中国农作物秸秆产量的变化,并估算2009年中国农作物秸秆资源的数量和地理分布。【方法】在已有研究的基础上,筛选出合适的秸秆系数,对中国田间秸秆产量进行全面、系统的估算,同时结合地理信息软件ArcView,对其时空分布进行分析。【结果】随着农业综合生产能力的提高,中国田间秸秆总量总体上呈不断增长的趋势;2009年全国作物秸秆总量达69 841.92万t;从种植结构的角度进行分析发现,稻谷、小麦和玉米秸秆依然是中国主要的农作物秸秆类型;中国农作物秸秆的分布基本上以400 mm等降水量线为界,其产量由西北向东南呈逐渐增加的趋势。【结论】中国的农作物秸秆分布具有一定的地域特征,且产量较大,具有可观的新能源开发利用前景。     

破解优质农副土特产品产销对接难题--以河南省为例

流通费用高企、产销脱节、品牌意识不强以及外销滞后等问题严重影响河南省优质农副土特产品的产销对接。为顺利实现产销对接,河南省各级政府应加强政策引导、加大财政投入,加快专业信息平台以及农村专业合作社建设;相关企业应开展差异化经营,树立名牌意识,积极开拓各种销售渠道;消费者应树立健康消费观念。     

Performance and Egg Characteristics of Laying Hens Fed Diets Incorporated with Poultry By-Product and Feather Meals

The effects of poultry by-product meal (PBPM) and feather meal (FM) incorporated separately and in combination in the diet on laying hen performance and egg characteristics during postpeak production were determined. Bovans White strain laying hens, 42 wk of age, were fed diets with 0% PBPM and FM, 5% FM, 5% PBPM, or 4% FM + 4% PBPM. Egg production, feed intake, and egg mass were not significantly affected by dietary treatments, whereas egg weight and feed conversion ratio (FCR) were significantly affected. Egg weights of hens receiving 4% FM + 4% PBPM were significantly lower than those fed the control diet, whereas those fed 5% FM or 5% PBPM were intermediate. FCR was significantly improved by the diets containing 5% FM or 5% PBPM compared with the diet containing 4% FM + 4% PBPM. Dietary PBPM decreased Haugh units, but FM did not. Egg breaking strength, shell weight, and weights of albumen and yolk were not affected by treatments. The results suggested that FM or PBPM could be incorporated up to 5% singly or up to 8% in combination in layer diets but with possible detrimental effects on Haugh units, egg weight, and FCR.     

农业科研副产品处置的困境及对策探讨

文章阐述了农业科研单位对科研副产品管理的现状及面临的问题,分析了农业科研副产品投入与产出的关系,并提出了以绩效考评为依据的科研副产品处置收入分配方式,从而达到优化科研人员收入分配机制的目的。     

Apparent digestibility of rendered animal protein ingredients for rainbow trout (Oncorhynchus mykiss)

The apparent digestibility of 20 rendered animal protein ingredients from various origins was determined in three digestibility trials. The ingredients consisted of eight blood meals, four feather meals, six meat and bone meals and two poultry by-product meals. Within each type of ingredient, a relatively large range of raw materials, processing conditions and equipment were represented. In each of three trials, a reference diet was mixed with test ingredients in a 70:30 ratio to produce a series of test diets. The reference and test diets were fed to rainbow trout reared at 15°C and fecal samples were collected using the “Guelph system”. Apparent digestibility coefficients (ADC) for protein and energy of the four feather meals varied between 81 and 87% and 76 and 80%. Significant differences in the ADC for protein of feather meal were observed and may be related to the drying equipment. The ADC for protein of the two poultry by-product meals was 87 and 91% and that of energy 77 and 87%. The ADC for protein and energy of the six meat and bone meals varied between 83 and 89% and 68 and 83%, respectively. Treatment of one of the meat and bone meals by air-classification to reduce its ash content resulted in a significant increase in the ADC for protein and lipid. ADC for protein of the blood meals varied between 82 and 99% whereas ADC for energy varied between 79 and 99%. Spray-dried blood products (whole blood, blood cells, blood plasma) were highly digestible (ADC protein=96-99%). Rotoplate-, steam-tube- and ring-dried blood meals had significantly lower ADC for protein and energy than spray-dried blood products.     

Properties of Edible Films Made From Anchovy By-Product Proteins and Determination of Optimum Protein and Glycerol Concentration by the TOPSIS Method

In the present study, the physicochemical and mechanical properties of films made from anchovy (Engraulis encrasicholus) by-product proteins (ABPs) were characterized as a function of protein (3, 4, and 5%) and glycerol (30, 40, 50, and 60%) concentration. In particular, the thickness, color, transparency, water vapor permeability (WVP), solubility, oxygen permeability (OP), and mechanical properties of the films were measured, and generally, these properties were affected by both protein and glycerol concentration. The thickness, redness, WVP and solubility values of films increased, while their lightness and yellowness values decreased as protein concentration increased. Furthermore, lightness, yellowness, and elongation at break (EAB) values were found to increase at higher glycerol concentrations within ABP films, whereas tensile strength (TS) and elastic modulus (EM) values decreased. ABP films became more transparent with increase of glycerol concentration and decrease of protein concentration. The OP values of all films decreased depending on protein and glycerol concentration. The techniques for order performance by similarity to ideal solution (TOPSIS) method was used to determine optimum protein and glycerol concentrations. According to this method, an edible film containing 4% protein and 40% glycerol was the best film with a C value of 0.6665.     

Dietary Protein Hydrolysates from Animal By-Products: Digestibility and Enzymatic Activity for Dourado Salminus brasiliensis

Fishmeal (FM) is a high-cost and scarce feedstuff. Notwithstanding, the formulation and processing of diets for carnivorous fish strongly rely on FM as a protein source, given its palatability and biological value. Animal by-product hydrolysates are high-quality feedstuff and can substitute FM in aquafeeds. This study evaluated the digestibility of hydrolysates from tilapia residue (TR), tuna head (TH), swine liver (SL), and poultry liver (PL), and the profile of digestive enzymes in juvenile dourado, Salminus brasiliensis, a carnivorous Characin, fed diets containing graded levels of the hydrolysates. Inclusion of hydrolysates in diet formulations lowered the pH of feed but did not alter feed intake by fish. Higher apparent digestibility coefficients (ADCs) of diets were recorded for fish fed diets containing TR and SL, and lower ADCs were recorded for fish fed diets containing TH. Protease and lipase activities in the animal’s stomach were higher, especially for those fed with diets containing SL. Amylase activity was higher in pyloric caeca, whereas in the intestines, the higher activity was seen in fish fed control and TR diets. Animal by-product hydrolysates were highly digestible for dourado, and the enzymatic profile of fish was influenced by the nutrient contents of diets.     

Fat Quality Assessments of Feed-Grade and Pet Food-Grade Poultry By-Product Meals

Ether extract composition of poultry by-product meal (PBM) varies among feed-grade and pet food-grade sources. Because feed-grade PBM contains a wider variety of processing residues than pet food-grade PBM, it is presumed to be of lower fat quality (i.e., stability). This potential difference in fat quality, or stability, between PBM sources can be accentuated by high environmental temperatures. A total of 46 PBM samples (25 feed-grade and 21 pet food-grade) were collected from commercial feed mills located in the southeastern US within 60-d intervals during the winter and summer months.For samples from winter collection, feed-grade PBM had lower fat stability than pet food-grade PBM. Conversely, pet food-grade PBM samples received in the summer were characterized as having poor stability, and the amount of analyzed residual antioxidant concentration in pet food-grade PBM was half that found in the feed-grade PBM samples. Seasonal effects appeared to be related to the extent of fat oxidation. In general, samples obtained in the summer had poor stability when compared with those collected during the winter, regardless of source. These results confirmed that fat in PBM requires an adequate amount of antioxidant protection, even when meals are derived from prime offal components.     

加氯消毒中细菌物质生成卤代乙腈研究

[目的]为研究加氯消毒过程中细菌物质生成卤代乙腈的情况。[方法]对水体中常见的5种细菌,按照UFC方法,测定了其生成N-DBPs和HANs的量,同时考察了溴离子对细菌加氯形成HANs的影响。[结果]细菌B1的单位耗氯量最大（1．96mgCl3／mgC）,B5最低（0．45mgCl2／mgC）;5种细菌加氯处理后有微量的TCAN生成,生成的DCAN随细菌TOC浓度呈近似线性关系;氯代HANs生成量占总HANs比例减少,溴代HANs随溴离子浓度的增加而在一定程度上增加。[结论]5种细菌均能生成HANs,以DCAN为主;溴离子对细菌物质生成HANs的影响较大。     

Optimal Conditions to Remove Chemical Hazards in Fish Protein Isolates from Tilapia Frame Using Response Surface Methodology

Response surface methodology (RSM) was employed to maximize the removal of phospholipids (PLs) and other chemical hazards in tilapia protein isolates made from tilapia frame (TF). CaCl₂ and the ratio of water to minced tilapia frame (W:TF) were the significant variables affecting PLs reduction. The optimum condition for maximal PLs reduction (90.0%) was: 10.25 mM CaCl₂ and a W:TF of 7.8:1, while other variables were fixed at 5 mM citric acid, 60 min incubation, pH 11, and centrifugal speed of 8,000 × g. At these conditions, the great reduction of lipids (93.9%), Hg (97.6%), and As (95.5%), as well as 86.1% of protein recovery, were obtained. Protein isolates with significantly reduced chemical hazards and lipids were successfully prepared from tilapia frames using the alkaline extraction assisted with CaCl₂ and citric acid.