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...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.展开更多
Pelleting is the most popular thermal processing technique in poultry industry. Birds fed pelleted diets have greater feed intake and weight gain, and better feed conversion ratio. However, this better performance can...Pelleting is the most popular thermal processing technique in poultry industry. Birds fed pelleted diets have greater feed intake and weight gain, and better feed conversion ratio. However, this better performance can only be achieved, if the pellets remain intact until they are ingested by the birds. Many factors may affect pellet physical quality, such as feed nutritional composition, ingredient particle size, conditioning temperature and time, feed moisture, etc.. Despite their importance, sometimes these factors are not managed properly, therefore, pelleted feed may not contain a high amount of intact pellets. In addition, the possible interactions among these variables may yield different responses in comparison with those expected when individual factors are considered. Very few experiments have been conducted to evaluate the impact of combined factors on pellet quality. This may be explained by the presence of many qualitative and quantitative factors in the manufacturing process. Research indicates that heat processing and feed formulation, especially fat inclusion level, are the factors which have the biggest influence on pellet quality. Strategies, such as the expansion process and fat inclusion restriction or post pellet liquid fat application could be implemented to produce high physical quality pellets. More research is needed to identify which factors have a positive or negative effect on pelleting process and to find new strategies to improve pellet physical quality.展开更多
A series of poly(vinyl acetate-co-acrylamide)copolymers with different mole ratios of vinyl acetate to acrylamide units were synthesized by emulsion polymerization for investigating the influences of copolymer composi...A series of poly(vinyl acetate-co-acrylamide)copolymers with different mole ratios of vinyl acetate to acrylamide units were synthesized by emulsion polymerization for investigating the influences of copolymer composition upon the performance such as apparent viscosity,film behaviors,and adhesion capacity to fibers for warp sizing operation.The mole ratios of vinyl acetate to acrylamide were varied from 0 to 4.By using an impregnated roving method,the adhesion was evaluated in terms of the maximal strength and work to break of a slightly sized roving.The film behaviors included breaking strength,breaking elongation,solution time and hygroscopic capacity.It was found that the viscosity,adhesion capability,glass transition temperature and film behaviors of the copolymeric sizing agent strongly depended on the mole ratio.Excessively increasing the amounts of vinyl acetate or acrylamide units incorporated into the copolymeric chains damages much of the performance.A favorable mole ratio of vinyl acetate or acrylamide was found to be 45∶55.Based on this mole ratio,the adhesion capability and film behaviors of the sizing agent reach their maximal values simultaneously.This demonstrates that the sizing agent should be synthesized under this copolymer composition from the viewpoint of adhesion and film behaviors.展开更多
A twelve week experiment was conducted to compare the effects of diets with plant-based and animal-based ingredients on growth and gonad development of Clarias gariepinus. One hundred and 12 sub-adult C. gariepinus wi...A twelve week experiment was conducted to compare the effects of diets with plant-based and animal-based ingredients on growth and gonad development of Clarias gariepinus. One hundred and 12 sub-adult C. gariepinus with an average weight of 205 ×5.09 g, were stocked in six concrete tanks （9 × 4 × 2 m3） containing 20 fish each. Experiment had 3 replicates and animals fed daily at 5% body weights. There was no significant difference （P 〈 0.05） in proximate compositions of the two experimental feeds and controls. Fecundity, gonad weight and gonasomatic index were higher in fish fed diet 13 than A and C. Similarly, growth indices were higher in fish fed diet B than in A and C. Histology of gonads showed a faster development of oocytes of eggs in fish fed animal-based ingredients than plant-based and combined plant and animal diets. Although there were slight differences in growth parameters and gonad development in favor of feed with animal-based ingredients, plant-based feed compared favorably in the growth and gonad development of C. gariepinus. Plant-based ingredients are recommended on the basis of affordability and availability as substitute for animal-based ingredients in C. gariepinus feed.展开更多
Among fertilizer ingredients nitrogen is the one noted for biggest losses because its susceptibility to volatilize to the atmosphere and to be leached away from the soil. These losses depend on the level and mode of f...Among fertilizer ingredients nitrogen is the one noted for biggest losses because its susceptibility to volatilize to the atmosphere and to be leached away from the soil. These losses depend on the level and mode of fertilization. It appears that every year in Poland river waters transport to the Baltic Sea from the whole area about 180 thousand tons of the nutrient. The largest portion of this load is ascribed to agriculture. This study focused on the highland areas, which are commonly seen as a water supplying region owing to the fact that they cover about 35% of water need in the authors＇ country. Specificity of grassland fertilization in these lands is high contribution of natural fertilizers including dunging with fresh manure left by penned animals, particularly by sheep. Authors decided to assess the influence of dunging by folded sheep on meadow nitrogen balance and on its concentration in percolating water. It was demonstrated that a nitrogen balance was highly negative for each object, so the grassland plants supplied their needs in large part with nitrogen from mineralization of soil organic matter. Relatively high loads of nitrogen leached out of the folded objects indicate that nitrogen from mineral fertilizers is better utilized by grassland herbage and thus is much safer for soil and water environment.展开更多
文摘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.
文摘Pelleting is the most popular thermal processing technique in poultry industry. Birds fed pelleted diets have greater feed intake and weight gain, and better feed conversion ratio. However, this better performance can only be achieved, if the pellets remain intact until they are ingested by the birds. Many factors may affect pellet physical quality, such as feed nutritional composition, ingredient particle size, conditioning temperature and time, feed moisture, etc.. Despite their importance, sometimes these factors are not managed properly, therefore, pelleted feed may not contain a high amount of intact pellets. In addition, the possible interactions among these variables may yield different responses in comparison with those expected when individual factors are considered. Very few experiments have been conducted to evaluate the impact of combined factors on pellet quality. This may be explained by the presence of many qualitative and quantitative factors in the manufacturing process. Research indicates that heat processing and feed formulation, especially fat inclusion level, are the factors which have the biggest influence on pellet quality. Strategies, such as the expansion process and fat inclusion restriction or post pellet liquid fat application could be implemented to produce high physical quality pellets. More research is needed to identify which factors have a positive or negative effect on pelleting process and to find new strategies to improve pellet physical quality.
基金The Foundation of Talented Persons in Anhui Province(No.2002Z036)
文摘A series of poly(vinyl acetate-co-acrylamide)copolymers with different mole ratios of vinyl acetate to acrylamide units were synthesized by emulsion polymerization for investigating the influences of copolymer composition upon the performance such as apparent viscosity,film behaviors,and adhesion capacity to fibers for warp sizing operation.The mole ratios of vinyl acetate to acrylamide were varied from 0 to 4.By using an impregnated roving method,the adhesion was evaluated in terms of the maximal strength and work to break of a slightly sized roving.The film behaviors included breaking strength,breaking elongation,solution time and hygroscopic capacity.It was found that the viscosity,adhesion capability,glass transition temperature and film behaviors of the copolymeric sizing agent strongly depended on the mole ratio.Excessively increasing the amounts of vinyl acetate or acrylamide units incorporated into the copolymeric chains damages much of the performance.A favorable mole ratio of vinyl acetate or acrylamide was found to be 45∶55.Based on this mole ratio,the adhesion capability and film behaviors of the sizing agent reach their maximal values simultaneously.This demonstrates that the sizing agent should be synthesized under this copolymer composition from the viewpoint of adhesion and film behaviors.
文摘A twelve week experiment was conducted to compare the effects of diets with plant-based and animal-based ingredients on growth and gonad development of Clarias gariepinus. One hundred and 12 sub-adult C. gariepinus with an average weight of 205 ×5.09 g, were stocked in six concrete tanks （9 × 4 × 2 m3） containing 20 fish each. Experiment had 3 replicates and animals fed daily at 5% body weights. There was no significant difference （P 〈 0.05） in proximate compositions of the two experimental feeds and controls. Fecundity, gonad weight and gonasomatic index were higher in fish fed diet 13 than A and C. Similarly, growth indices were higher in fish fed diet B than in A and C. Histology of gonads showed a faster development of oocytes of eggs in fish fed animal-based ingredients than plant-based and combined plant and animal diets. Although there were slight differences in growth parameters and gonad development in favor of feed with animal-based ingredients, plant-based feed compared favorably in the growth and gonad development of C. gariepinus. Plant-based ingredients are recommended on the basis of affordability and availability as substitute for animal-based ingredients in C. gariepinus feed.
文摘Among fertilizer ingredients nitrogen is the one noted for biggest losses because its susceptibility to volatilize to the atmosphere and to be leached away from the soil. These losses depend on the level and mode of fertilization. It appears that every year in Poland river waters transport to the Baltic Sea from the whole area about 180 thousand tons of the nutrient. The largest portion of this load is ascribed to agriculture. This study focused on the highland areas, which are commonly seen as a water supplying region owing to the fact that they cover about 35% of water need in the authors＇ country. Specificity of grassland fertilization in these lands is high contribution of natural fertilizers including dunging with fresh manure left by penned animals, particularly by sheep. Authors decided to assess the influence of dunging by folded sheep on meadow nitrogen balance and on its concentration in percolating water. It was demonstrated that a nitrogen balance was highly negative for each object, so the grassland plants supplied their needs in large part with nitrogen from mineralization of soil organic matter. Relatively high loads of nitrogen leached out of the folded objects indicate that nitrogen from mineral fertilizers is better utilized by grassland herbage and thus is much safer for soil and water environment.
