The phenyl and methyl phenyl free radicals,formed in the oxidation-hydrolysis process of N’-acyl-N-phenylhydrazine, have been studied by ESR spectrometry.It was found that the free radical is the chief cause which pr...The phenyl and methyl phenyl free radicals,formed in the oxidation-hydrolysis process of N’-acyl-N-phenylhydrazine, have been studied by ESR spectrometry.It was found that the free radical is the chief cause which produces the feed-back inhibition effect in the hydrazine-promoted infectious development of silver halide.展开更多
Traditional Chinese medicine Pseudostellaria heterophylla fibrous roots have been widely studied and applied in non-antibiotic clinical breeding of livestock and poultry. In vitro probiotic effect of P. heterophylla f...Traditional Chinese medicine Pseudostellaria heterophylla fibrous roots have been widely studied and applied in non-antibiotic clinical breeding of livestock and poultry. In vitro probiotic effect of P. heterophylla fibrous roots extract on feed probiotics Bacillus subtilis BD-K010 was studied, and the feasibility of solid fermentation of P. heterophylla fibrous roots was preliminarily evaluated. For in vitro probiotic effect, the increased concentration of P. heterophylla fibrous roots extract dependently increased the total biomass of B. subtilis BD-K010;1.0% P. heterophylla fibrous roots extract received the best effect, and the final p H of 1.0% experimental group was closer to neutral. Meantime, B. subtilis BD-K010 with optimum concentration of P. heterophylla fibrous roots showed significantly higher in vitro antibacterial effect than the control group(P<0.01),and the antibacterial effects on Escherichia coli and Staphylococcus aureus were improved by 51.99% and 63.16%, but it was ineffective to Salmonella. For solid fermentation, the profile of substrate complex and appendage flocculent structure on substrate surface at the end of fermenta-tion in experimental groups added with B. subtilis BD-K010 and cellulase plus BD-K010 were more complex;the live bacteria number, polysaccharide content and saponin content at fermentation end-point in two experimental groups were extremely higher than those in the control group(P<0.01).P. heterophylla fibrous roots extract had good in vitro probiotic effect on B. subtilis BD-K010 and promoted its antibacterial effect, and it is feasible to use probiotics for solid fermentation of P. heterophylla fibrous roots and to improve effective components. It is of great significance to further de-velop and utilize P. heterophylla fibrous roots resources in modern animal husbandry.展开更多
This paper investigates the thermal-coupled effect across the wall and the optimal heat transfer region of the wall for enhancing the energy saving effect of dividing wall column (DWC), and also studies the effects of...This paper investigates the thermal-coupled effect across the wall and the optimal heat transfer region of the wall for enhancing the energy saving effect of dividing wall column (DWC), and also studies the effects of feed thermal condition (q) and middle component composition of feed (cB) on the heat transfer process, the optimal heat transfer region, and the maximum heat transfer quantity across the wall. The simulation results show that the maximum heat transfer quantity across the wall and the potential for energy saving increase with the increase of q, while with the limitation of temperature difference across the wall, the beneficial heat transfer effect between certain range of stages, which are involved in the optimal heat transfer region, cannot be realized completely for a specific value of q. Besides, compared with q, a changing cB does not change the degree of realizing the beneficial heat transfer effect, but can bring about the variation of liquid split ratio (RL) and vapor split ratio (Rv). Thus, for achieving a maximum energy-saving effect of DWC, different q and cB need to find its own corresponding suitable heat transfer process across the wall.展开更多
Feed intolerance in the setting of critical illness is associated with higher morbidity and mortality,and thusrequires promptly and effective treatment. Prokineticagents are currently considered as the first-line ther...Feed intolerance in the setting of critical illness is associated with higher morbidity and mortality,and thusrequires promptly and effective treatment. Prokineticagents are currently considered as the first-line therapygiven issues relating to parenteral nutrition and post-pyloric placement. Currently,the agents of choice areerythromycin and metoclopramide,either alone or incombination,which are highly effective with relativelylow incidence of cardiac,hemodynamic or neurologicaladverse effects. Diarrhea,however,can occur in up to 49% of patients who are treated with the dual prokinetic therapy,which is not associated with Clostridiumdifficile infection and settled soon after the cessation ofthe drugs. Hence,the use of prokinetic therapy over along period or for prophylactic purpose must be avoided,and the indication for ongoing use of the drug(s)must be reviewed frequently. Second line therapy,suchas total parenteral nutrition and post-pyloric feeding,must be considered once adverse effects relating theprokinetic therapy develop.展开更多
The preliminary results of this laboratory (unpublished) indicate that the nutritional value of whole wheat hay (wheat hay, for short) is very high, and the milk stage is the best period of wheat hay harvest. In this ...The preliminary results of this laboratory (unpublished) indicate that the nutritional value of whole wheat hay (wheat hay, for short) is very high, and the milk stage is the best period of wheat hay harvest. In this study, we investigated the feeding effect and economic benefits using wheat hay instead of alfalfa diet for dairy cows under the condition of the same energy and crude protein levels. Three types of diets were used: alfalfa diet, wheat hay diet and alfalfa + wheat hay diet. The results showed that the dry matter digestibility of alfalfa diet and alfalfa + wheat hay diet did not differ significantly (P > 0.1), but was significantly higher than that of wheat hay diet (P < 0.05). The wheat hay diet could produce more propionic acid and ammonia nitrogen (P < 0.05) in the rumen, and reduce the ratio of acetic/propionic and nitrogen utilization. There was no significant difference in milk production among the three diets (P > 0.1). There was no significant difference in milk somatic cell count and body condition score among the three groups (P > 0.1). The wheat hay diet could significantly increase milk protein and lactose (P contents of interleukin-6 in cows fed alfalfa diet and alfalfa + wheat diet were significantly higher than that in cows fed wheat hay diet (P < 0.05). There was no significant difference in interleukinm-6 between in cows fed alfalfa diet and alfalfa + wheat diet (P > 0.05). The use of wheat hay to replace imported alfalfa in whole or in part could save feed costs. Full substitution of alfalfa with wheat hay could have a daily economic benefit of 13.74 yuan.展开更多
The establishment of drug-free feeding systems has been required for secure and healthy livestock production. Although functional feed materials containing microorganisms as alternatives to enhance intestinal immunity...The establishment of drug-free feeding systems has been required for secure and healthy livestock production. Although functional feed materials containing microorganisms as alternatives to enhance intestinal immunity are expected to be beneficial for reducing diarrhoea caused by pathogens in weaned piglets, the effects of such materials on porcine intestinal cells have not been investigated in detail. Therefore, this work evaluated the immunoregulatory functions of microbial feed materials in porcine intestinal immune and epithelial cells. Porcine immune cells isolated from Peyer’s patches and mesenteric lymph nodes were stimulated with six different feed materials containing microorganisms, and evaluated for lymphocyte mitogenicity and cytokine inductions. In addition, porcine intestinal epithelial cells were stimulated with the materials before treatment with heat-killed enterotoxigenic Escherichia coli (ETEC), and analyzed for the proinflammatory cytokine expressions. The material containing Bifidobacterium thermophilum significantly augmented lymphocytes’ mitogenicity and also induced a high expression of IL-2, IL-6 and IFN-γ in immune cells, and inhibited ETEC-induced overexpression of IL-6 and IL-8 via regulation of Toll-like receptor signaling. These results suggest that this feed material stimulates intestinal epithelial and immune cells to exert immunoregulation, suggesting that this feed is expected to contribute to promoting the health of piglets without using antimicrobial feed materials.展开更多
Searching alternative feed antibiotics is always a study hotspot in the field of animal production. In this study, the antipathogenic activities and probiotics stimulatory effects of 30 kinds of herbs were screened th...Searching alternative feed antibiotics is always a study hotspot in the field of animal production. In this study, the antipathogenic activities and probiotics stimulatory effects of 30 kinds of herbs were screened through Oxford cup method and Hungate roll method. 15 herbs showed significantly antibacterial activities（P〈0.05） against Escherichia coli, Salmonella enteritidis, Salmonella typhimurium and Staphylococcus aureus. Seven herbs showed greatly stimulatory promoting effects on Lactobacillus acidophilus and Bifidobacterium longum. Finally, five herbs were combined for the developed formulation with selective antibacterial properties and they were Mume Fructus（35%）, Isatidis Folium（25%）, Moslae Herba（20%）, Chrysanthemi Indici Flos（13%） and Bupleuri Radix（7%）. The herbal formulation showed significantly antibacterial abilities against four pathogens and stimulatory promoting abilities on two probiotics in vitro and the equivalent activities in broiler chickens in vivo against E. coli and L. acidophilus. The toxicity study showed it had no toxicity, which indicated that it would be a kind of preferred candidate for an alternative antibiotic in future animal production.展开更多
Mammalian feeding behavior is often acquired or improved by learning. Social learners are thought to attain novel information or skills faster and at lower cost than asocial learners. In this study, we examined what t...Mammalian feeding behavior is often acquired or improved by learning. Social learners are thought to attain novel information or skills faster and at lower cost than asocial learners. In this study, we examined what types of learning affect the acquisition of efficient feeding behavior by the wood mouse Apodemus speciosus when feeding on large, hard-shelled walnuts. In house cages, na?ve mice acquired an efficient feeding manner during the 14-day conditioning to walnuts, suggesting individual trial-and-error learning contributes to their feeding skills. Social factors such as learning from walnuts that have been opened by other individuals or by observing walnut consumption by proficient conspecifics did not affect the rate of acquisition of efficient feeding. However, weaned offspring could eat walnuts more efficiently and frequently if the mother had been given walnuts during her rearing period. Thus, the skill is likely transmitted between the mother and offspring in addition to individual self-learning.展开更多
[Objectives] This study was conducted to expand the insect resistance spectrum of tea saponin, and its control effect on Cylas formicarius and the potential as an insecticide for pest control were explored. [Methods] ...[Objectives] This study was conducted to expand the insect resistance spectrum of tea saponin, and its control effect on Cylas formicarius and the potential as an insecticide for pest control were explored. [Methods] The olfactory avoidance rate of C. formicarius to tea saponin aqueous solution was determined by Y-type olfactometer;the feeding avoidance rate of C. formicarius to tea saponin was determined by the selective method;the antifeedant rate of C. formicarius to tea saponin was determined by non-selective method;and the development duration and mortality of C. formicarius under the influence of tea saponin were determined by artificial feeding method. [Results] C. formicarius had no significant olfactory tendency to every concentration of tea saponin, and the olfactory avoidance rate of 20.0% tea saponin aqueous solution was only 9.14%. Tea saponin had a feeding avoidance effect on C. formicarius, and the avoidance rate increased with the increase of tea saponin concentration. At 6 h, the feeding avoidance rates of 0.5%, 1.0%, 5.0%, 10.0% and 20.0% tea saponin on C. formicarius were 58.14%, 77.77%, 88.23%, 95.00% and 97.65 %, respectively;and the feeding avoidance effect at 6 h was significant, and the feeding avoidance rate was higher than that of 1 h. Tea saponin had a significant antifeedant effect on C. formicarius, and the longer the feeding time, the higher the antifeedant rate. At 72 h, the antifeedant rates of 0.5%, 1.0%, 5.0%, 10.0 % and 20.0% tea saponin to C. formicarius were 63.01%, 67.54%, 97.14 %, 96.42% and 98.57%, respectively. The larval development duration of C. formicarius was shortened with the increase of tea saponin concentration, and the larval death occurred. The development duration of larvae under the influence of 1.0% tea saponin was the shortest, which was 4.01 d shorter than that of the control, and the mortality was the highest, which was 26.65%. [Conclusions] Tea saponin had neither olfactory avoidance effect nor olfactory attracting effect to C. formicarius, but had obvious feeding avoidance effect and strong antifeedant effect. Tea saponin can shorten the development duration of the larvae of C. formicarius and cause the death of the larvae.展开更多
Stribeck effect is regarded as the most important feed-axis friction characteristics. According to the relationship between friction and lubrication,a rapid technology for feed-axis lubrication condition evaluation of...Stribeck effect is regarded as the most important feed-axis friction characteristics. According to the relationship between friction and lubrication,a rapid technology for feed-axis lubrication condition evaluation of computer numerical control( CNC) machine tools based on soft sensor is proposed. To obtain its state information,the static friction force,Coulomb friction force,and viscous coefficient are used as the key parameters of the soft sensor for tread analysis. Then the various amplitude and velocity triangular wave test curve, and a precise nonlinear model identification method are presented. The results of the experiments analysis show that this method is feasible and reliable for evaluating feed-axis lubrication condition,which lays the foundation for on-line condition monitoring and reliability evaluation for feed-axis lubrication of machine tools.展开更多
文摘The phenyl and methyl phenyl free radicals,formed in the oxidation-hydrolysis process of N’-acyl-N-phenylhydrazine, have been studied by ESR spectrometry.It was found that the free radical is the chief cause which produces the feed-back inhibition effect in the hydrazine-promoted infectious development of silver halide.
基金Supported by Innovation Fund Project of Fujian Provincial Department of Science and Technology(2018C0041)Soft Science Project of Fujian Provincial Intellectual Property Office(2018ER019)
文摘Traditional Chinese medicine Pseudostellaria heterophylla fibrous roots have been widely studied and applied in non-antibiotic clinical breeding of livestock and poultry. In vitro probiotic effect of P. heterophylla fibrous roots extract on feed probiotics Bacillus subtilis BD-K010 was studied, and the feasibility of solid fermentation of P. heterophylla fibrous roots was preliminarily evaluated. For in vitro probiotic effect, the increased concentration of P. heterophylla fibrous roots extract dependently increased the total biomass of B. subtilis BD-K010;1.0% P. heterophylla fibrous roots extract received the best effect, and the final p H of 1.0% experimental group was closer to neutral. Meantime, B. subtilis BD-K010 with optimum concentration of P. heterophylla fibrous roots showed significantly higher in vitro antibacterial effect than the control group(P<0.01),and the antibacterial effects on Escherichia coli and Staphylococcus aureus were improved by 51.99% and 63.16%, but it was ineffective to Salmonella. For solid fermentation, the profile of substrate complex and appendage flocculent structure on substrate surface at the end of fermenta-tion in experimental groups added with B. subtilis BD-K010 and cellulase plus BD-K010 were more complex;the live bacteria number, polysaccharide content and saponin content at fermentation end-point in two experimental groups were extremely higher than those in the control group(P<0.01).P. heterophylla fibrous roots extract had good in vitro probiotic effect on B. subtilis BD-K010 and promoted its antibacterial effect, and it is feasible to use probiotics for solid fermentation of P. heterophylla fibrous roots and to improve effective components. It is of great significance to further de-velop and utilize P. heterophylla fibrous roots resources in modern animal husbandry.
基金supported by the Natural Science Research Youth Foundation of Hebei Higher Education of China [QN2016084]the National Natural Science Foundation of China[21878066]
文摘This paper investigates the thermal-coupled effect across the wall and the optimal heat transfer region of the wall for enhancing the energy saving effect of dividing wall column (DWC), and also studies the effects of feed thermal condition (q) and middle component composition of feed (cB) on the heat transfer process, the optimal heat transfer region, and the maximum heat transfer quantity across the wall. The simulation results show that the maximum heat transfer quantity across the wall and the potential for energy saving increase with the increase of q, while with the limitation of temperature difference across the wall, the beneficial heat transfer effect between certain range of stages, which are involved in the optimal heat transfer region, cannot be realized completely for a specific value of q. Besides, compared with q, a changing cB does not change the degree of realizing the beneficial heat transfer effect, but can bring about the variation of liquid split ratio (RL) and vapor split ratio (Rv). Thus, for achieving a maximum energy-saving effect of DWC, different q and cB need to find its own corresponding suitable heat transfer process across the wall.
文摘Feed intolerance in the setting of critical illness is associated with higher morbidity and mortality,and thusrequires promptly and effective treatment. Prokineticagents are currently considered as the first-line therapygiven issues relating to parenteral nutrition and post-pyloric placement. Currently,the agents of choice areerythromycin and metoclopramide,either alone or incombination,which are highly effective with relativelylow incidence of cardiac,hemodynamic or neurologicaladverse effects. Diarrhea,however,can occur in up to 49% of patients who are treated with the dual prokinetic therapy,which is not associated with Clostridiumdifficile infection and settled soon after the cessation ofthe drugs. Hence,the use of prokinetic therapy over along period or for prophylactic purpose must be avoided,and the indication for ongoing use of the drug(s)must be reviewed frequently. Second line therapy,suchas total parenteral nutrition and post-pyloric feeding,must be considered once adverse effects relating theprokinetic therapy develop.
文摘The preliminary results of this laboratory (unpublished) indicate that the nutritional value of whole wheat hay (wheat hay, for short) is very high, and the milk stage is the best period of wheat hay harvest. In this study, we investigated the feeding effect and economic benefits using wheat hay instead of alfalfa diet for dairy cows under the condition of the same energy and crude protein levels. Three types of diets were used: alfalfa diet, wheat hay diet and alfalfa + wheat hay diet. The results showed that the dry matter digestibility of alfalfa diet and alfalfa + wheat hay diet did not differ significantly (P > 0.1), but was significantly higher than that of wheat hay diet (P < 0.05). The wheat hay diet could produce more propionic acid and ammonia nitrogen (P < 0.05) in the rumen, and reduce the ratio of acetic/propionic and nitrogen utilization. There was no significant difference in milk production among the three diets (P > 0.1). There was no significant difference in milk somatic cell count and body condition score among the three groups (P > 0.1). The wheat hay diet could significantly increase milk protein and lactose (P contents of interleukin-6 in cows fed alfalfa diet and alfalfa + wheat diet were significantly higher than that in cows fed wheat hay diet (P < 0.05). There was no significant difference in interleukinm-6 between in cows fed alfalfa diet and alfalfa + wheat diet (P > 0.05). The use of wheat hay to replace imported alfalfa in whole or in part could save feed costs. Full substitution of alfalfa with wheat hay could have a daily economic benefit of 13.74 yuan.
文摘The establishment of drug-free feeding systems has been required for secure and healthy livestock production. Although functional feed materials containing microorganisms as alternatives to enhance intestinal immunity are expected to be beneficial for reducing diarrhoea caused by pathogens in weaned piglets, the effects of such materials on porcine intestinal cells have not been investigated in detail. Therefore, this work evaluated the immunoregulatory functions of microbial feed materials in porcine intestinal immune and epithelial cells. Porcine immune cells isolated from Peyer’s patches and mesenteric lymph nodes were stimulated with six different feed materials containing microorganisms, and evaluated for lymphocyte mitogenicity and cytokine inductions. In addition, porcine intestinal epithelial cells were stimulated with the materials before treatment with heat-killed enterotoxigenic Escherichia coli (ETEC), and analyzed for the proinflammatory cytokine expressions. The material containing Bifidobacterium thermophilum significantly augmented lymphocytes’ mitogenicity and also induced a high expression of IL-2, IL-6 and IFN-γ in immune cells, and inhibited ETEC-induced overexpression of IL-6 and IL-8 via regulation of Toll-like receptor signaling. These results suggest that this feed material stimulates intestinal epithelial and immune cells to exert immunoregulation, suggesting that this feed is expected to contribute to promoting the health of piglets without using antimicrobial feed materials.
基金supported by Hebei Science and Technology Support Program of China (13226602D)
文摘Searching alternative feed antibiotics is always a study hotspot in the field of animal production. In this study, the antipathogenic activities and probiotics stimulatory effects of 30 kinds of herbs were screened through Oxford cup method and Hungate roll method. 15 herbs showed significantly antibacterial activities（P〈0.05） against Escherichia coli, Salmonella enteritidis, Salmonella typhimurium and Staphylococcus aureus. Seven herbs showed greatly stimulatory promoting effects on Lactobacillus acidophilus and Bifidobacterium longum. Finally, five herbs were combined for the developed formulation with selective antibacterial properties and they were Mume Fructus（35%）, Isatidis Folium（25%）, Moslae Herba（20%）, Chrysanthemi Indici Flos（13%） and Bupleuri Radix（7%）. The herbal formulation showed significantly antibacterial abilities against four pathogens and stimulatory promoting abilities on two probiotics in vitro and the equivalent activities in broiler chickens in vivo against E. coli and L. acidophilus. The toxicity study showed it had no toxicity, which indicated that it would be a kind of preferred candidate for an alternative antibiotic in future animal production.
文摘Mammalian feeding behavior is often acquired or improved by learning. Social learners are thought to attain novel information or skills faster and at lower cost than asocial learners. In this study, we examined what types of learning affect the acquisition of efficient feeding behavior by the wood mouse Apodemus speciosus when feeding on large, hard-shelled walnuts. In house cages, na?ve mice acquired an efficient feeding manner during the 14-day conditioning to walnuts, suggesting individual trial-and-error learning contributes to their feeding skills. Social factors such as learning from walnuts that have been opened by other individuals or by observing walnut consumption by proficient conspecifics did not affect the rate of acquisition of efficient feeding. However, weaned offspring could eat walnuts more efficiently and frequently if the mother had been given walnuts during her rearing period. Thus, the skill is likely transmitted between the mother and offspring in addition to individual self-learning.
基金Supported by National Modern Agricultural Industry Technology System Guangxi Industry Potato Innovation Team(nycytxgxcxtd-11-01)Guangxi Science and Technology Planning Project(GK AB16380046,GK AB18221101)
文摘[Objectives] This study was conducted to expand the insect resistance spectrum of tea saponin, and its control effect on Cylas formicarius and the potential as an insecticide for pest control were explored. [Methods] The olfactory avoidance rate of C. formicarius to tea saponin aqueous solution was determined by Y-type olfactometer;the feeding avoidance rate of C. formicarius to tea saponin was determined by the selective method;the antifeedant rate of C. formicarius to tea saponin was determined by non-selective method;and the development duration and mortality of C. formicarius under the influence of tea saponin were determined by artificial feeding method. [Results] C. formicarius had no significant olfactory tendency to every concentration of tea saponin, and the olfactory avoidance rate of 20.0% tea saponin aqueous solution was only 9.14%. Tea saponin had a feeding avoidance effect on C. formicarius, and the avoidance rate increased with the increase of tea saponin concentration. At 6 h, the feeding avoidance rates of 0.5%, 1.0%, 5.0%, 10.0% and 20.0% tea saponin on C. formicarius were 58.14%, 77.77%, 88.23%, 95.00% and 97.65 %, respectively;and the feeding avoidance effect at 6 h was significant, and the feeding avoidance rate was higher than that of 1 h. Tea saponin had a significant antifeedant effect on C. formicarius, and the longer the feeding time, the higher the antifeedant rate. At 72 h, the antifeedant rates of 0.5%, 1.0%, 5.0%, 10.0 % and 20.0% tea saponin to C. formicarius were 63.01%, 67.54%, 97.14 %, 96.42% and 98.57%, respectively. The larval development duration of C. formicarius was shortened with the increase of tea saponin concentration, and the larval death occurred. The development duration of larvae under the influence of 1.0% tea saponin was the shortest, which was 4.01 d shorter than that of the control, and the mortality was the highest, which was 26.65%. [Conclusions] Tea saponin had neither olfactory avoidance effect nor olfactory attracting effect to C. formicarius, but had obvious feeding avoidance effect and strong antifeedant effect. Tea saponin can shorten the development duration of the larvae of C. formicarius and cause the death of the larvae.
基金National Natural Science Foundation of China(No.51305324)
文摘Stribeck effect is regarded as the most important feed-axis friction characteristics. According to the relationship between friction and lubrication,a rapid technology for feed-axis lubrication condition evaluation of computer numerical control( CNC) machine tools based on soft sensor is proposed. To obtain its state information,the static friction force,Coulomb friction force,and viscous coefficient are used as the key parameters of the soft sensor for tread analysis. Then the various amplitude and velocity triangular wave test curve, and a precise nonlinear model identification method are presented. The results of the experiments analysis show that this method is feasible and reliable for evaluating feed-axis lubrication condition,which lays the foundation for on-line condition monitoring and reliability evaluation for feed-axis lubrication of machine tools.
