常用精料干物质和脂肪在瘤胃中降解规律的研究

本试验用尼龙袋技术测定了肉牛常用精料玉米、芝麻饼、菜籽粕、豆粕、棉籽粕、油葵粕、棉籽饼、大豆和鸡杂的干物质和脂肪在瘤胃中的降解率。结果表明，４８小时的大豆干物质降解率最高，达９６．８％，其次是大豆粕、玉米和芝麻饼，分别为８９．３％，８９．０％、８８．４％，再次是菜籽粕、棉籽粕和棉籽饼，分别为７９．２％、７８．４％和７７．６％。鸡杂的干物质降解率为６６．５％，在所测定的样品中最低。４８小时的棉籽粕、菜籽粕、大豆和大豆粕的脂肪降解率最高，分别为９８．９％、９８．７％、９８．５％、９６．９％。其次是棉籽饼、芝麻饼、鸡杂、油葵饼和玉米，分别为９３．７％、８９．７％、８８．６％、８８．３％、８３．６％。尽管鸡杂是动物性饲料，但４８小时的脂肪降解率与其它植物性饲料的脂肪降解率差别并不大。

Cloning and Sequence Analysis of HN and F Protein Genes from a Strain of Goose Paramyxovirus

[ Objective] The study was to clone HN and F genes from GX1 strain of goose paramyxovirus and analyze their sequences. [ Method] According to the full nucleotide sequence of GPV-SF02 strain of goose paramyxovirus, two pairs of pdmers were designed to amplify the HN and F genes from GX1 strain of goose paramyxovirus isolated from diseased goose in Guangxi Zhuang Autonomous Region; the amplified products were ligated into pMD18-T vector and sequenced. [ Result ] HN and F genes of this strain tested were 1 716 and 1 662 bp in full nucleotide length, respectively; both showed the homologues of about 97.3% with GPV- SF02 strain, of 80.3% -97.5% with strains LaSota, F48E9 and JS, of just 84.8% with Miyadera strain. [ Conclusion] The results show that isolated strain BX1 matches to virulent APMV-1 strain, belonging to genotype Ⅶ of APMV-1 strain.

Rate Coefficients and Branching Ratio for Multi-Channel Hydrogen Abstractions from CH3OH by F

The hydrogen abstraction reaction F+CH3OH has two possible reaction pathways: HF+CH3O and HF+CH2OH. Despite the absence of intrinsic barriers for both channels, the former has a branching ratio comparable to the latter, which is far from the statistical limit of 0.25 (one out of four available H atoms). Furthermore, the measured branching ratio of the two abstraction channels spans a large range and is not quantitatively reproduced by previous theoretical predictions based on the transition-state theory with the stationary point information calculated at the levels of MФller-Plesset perturbation theory and G2. This work reports a theoretical investigation on the kinetics and the associated branching ratio of the two competing channels of the title reaction using a quasi-classical trajectory approach on an accurate full-dimensional potential energy surface (PES) fitted by the permutation invariant polynomial-neural network approach to ca. 1.21x10^5 points calculated at the explicitly correlated (F12a) version of coupled cluster singles doubles and perturbative triples (CCSD(T)) level with the aug-cc-pVDZ basis set. The calculated room temperature rate coeffcient and branching ratio of the HF+CH3O channel are in good agreement with the available experimental data. Furthermore, our theory predicts that rate coeffcients have a slightly negative temperature dependence, consistent with barrierless nature of the reaction.

Chemical Composition and Nutritive Value of Ramie Plant [Boehmeria nivea （L.） Gaud] and Its By-Products from the Textile Industry as Feed for Ruminants

In order to verify the possible use of ramie as feed for ruminants, a study was undertaken on the chemical and nutritional evaluation of different parts of this plant. Four stocks of samples picked up in two different periods （summer and autumn） were analyzed. The standard chemical composition was determined on the whole plant and on its parts, the study was particularly focused on leaves and tops, not used in fibre production and available as livestock feed. Organic matter enzymic digestibility （OMD） was determined on all the samples by a double step method based on cellnlolytic andproteolytic enzymes. The chemical analysis showed good crude proteins content in leaves, tops and whole plant： 17.00 ~ 1.52%, 15.25 ~ 0.77% and 11.79 ~ 3.32% on dry matter （DM） basis respectively and good acid （ADF） and neutral （NDF） detergent fibre fractions. Lignin and ash resulted high in all plant parts and organic matter （OM） was consequently low, ash analysis showed high calcium concentration, especially in leaves, with values exceeding 4% of din, whereas the other micro （except the lead） and macroelements were in a normal range. OMD and energy values resulted poor in leaves, tops and in the whole plant and lower than the other forages commonly used as feed for runninants, thus the utilisation of ramie plant and its by-products requests further investigations.

The Use of Coffee Pulp as a Potential Alternative Supplement in Ruminant Diets

The study was conducted to evaluate the use of dried industrial coffee pulp in diets as supplement for ruminants. Two diets were formulated： A and B with 30% coffee pulp content each and different concentrations of carbohydrates （milled corn, corn bran, molasses, alfalfa hay） and fibrous residues （corn stubble, sugar cane mash） as ingredients. The dried coffee pulp was subjected to proximate analyses, whilst the two diets were subjected to nutritional and microbiological analyses. The results of the proximate analyses showed that the dried coffee pulp has 18% crude protein （CP）, 33.6% crude fibre （CF） and total digestible nutrients （TDN） content of 63.8%. Diets A and B had the similar mean values for CP, CF and TDN （17%, 4.3% and 75.6%, respectively）. The microbiological results showed that the two diets had the same minimal values for Escherichia coli, Salmonella spp. and coliform bacteria, which were all within the normal allowed values. The results indicate that dry coffee pulp in diets could be supplemented to ruminants for supporting milk and meat production without any adverse effect on their health.

Pyrolysis Characteristics and Kinetics of Municipal Solid Waste

Based on a systemic survey, the pyrolysis characteristics and apparent kinetics of the municipal solid waste （ MSW） under different conditions were researched using a special pyrolysis reactor, which could overcome the disadvantage of thermo-gravimetric analyzer. The thermal decomposition behaviour of MSW was investigated using thermo-gravimetric （ TG ） analysis at rates of 4.8,6.6,8.4, 12.0 and 13. 2 K/min. The pyrolysis characteristics of MSW were also studied in different function districts. The pyrolysis of MSW is a complex reaction process and three main stages are found according to the results. The first stage represents the degradation of cellulose and hemicellulose, with the maximum degradation rate occuring at 150℃ -200 ℃： the second stage represents dehydrochlorination and depolymerization of intermediate products and the differential thermogravimetric （ DTG ） curves have shoulder peaks at about 300℃： the third stage is the decomposition of the residual big molecular organic substance and lignin at 400 ℃- 600 ℃. Within the range of given experimental conditions, the results of non-linear fitting algorithm and experiment are in agreement with each other and the correlation coefficients are over0. 99. The kinetic characteristics are concerned with the material component and heating rate. The activation energy of reaction decreases with the increase of heating rate.