In order to understand the incidence reasons in a scaled pig farm of Guizhou Province, the infected pigs were diagnosed with epidemiological investigation, clinical observation, pathological diagnosis, enzyme-linked i...In order to understand the incidence reasons in a scaled pig farm of Guizhou Province, the infected pigs were diagnosed with epidemiological investigation, clinical observation, pathological diagnosis, enzyme-linked immunosorbent assay (ELISA), PCR/RT-PCR and bacterial isolation and identification. The results showed that the pigs were infected mixedly with classical swine fever virus (CSFV), pseudorabies virus (PRV) and E. coli. Therefore, some measures should be adopted to control the incidence of CSF, PR and colibacillosis in the pig farm.展开更多
The application model of epidemic disease assessment technology for Web-based large-scale pig farm was expounded from the identification of epidemic disease risk factors, construction of risk assessment model and deve...The application model of epidemic disease assessment technology for Web-based large-scale pig farm was expounded from the identification of epidemic disease risk factors, construction of risk assessment model and development of risk assessment system. The assessed pig farm uploaded the epidemic disease risk data information through on-line answering evaluating questionnaire to get the immediate evaluation report. The model could enhance the risk communication between pig farm veterinarian, manager and veterinary experts to help farm system understand and find disease risk factors, assess and report the potential high risk items of the pig farm in the three systems of engineering epidemic disease prevention technology, biological safety and immune monitoring, and promote the improvement and perfection of epidemic disease prevention and control measures.展开更多
Emergence of Chinese economy together with the current Livestock Revolution in Asia have led to an increase of meat demands, specially pork that is reflected in the growth of commercial pig farms in peri-urban areas o...Emergence of Chinese economy together with the current Livestock Revolution in Asia have led to an increase of meat demands, specially pork that is reflected in the growth of commercial pig farms in peri-urban areas of Beijing, capital of People's Republic of China. In the framework of the International Research Training Group and of the Sino-Project Recycling of Organic Residues from Agricultural and Municipal Origin in China, the status quo of a large pig farm is researched. The first phase of the project was focused on a detailed description of the nutrients and trace elements contained in the main inputs (water, feed) and outputs (manure, wastewater) of the pig farm. The compliance with the Chinese national standards or often referred to as GB standards (in Chinese "GuoBiao") and, current German recommendations were included. The analysis of nutrients and trace minerals followed the natural structure of the pig life cycle, i.e., gestation, farrowing, weaning and fattening. The main results showed that the pig drinking water met the recommendations for livestock drinking water, ground water and human drinking water. Concentrations of Zn, Cu, Mn and As in the pig feeds samples displayed higher values compared to the Chinese and German recommendations. Average values of trace elements in the pig manure did not surpass the Chinese and German recommendations of biowastes, however, some manure samples showed excessive concentrations of Cd, Cu and Zn. Likewise, Pb, Cd, Cr, Cu and Zn concentrations in the wastewater surpassed the recommendations for irrigation water.展开更多
Foot-and-mouth disease(FMD)is an acute,highly infectious and pathogenic animal disease.In recent years,with the rapid development of the swine breeding industry in China,pig farms have shown a trend of larger-scale de...Foot-and-mouth disease(FMD)is an acute,highly infectious and pathogenic animal disease.In recent years,with the rapid development of the swine breeding industry in China,pig farms have shown a trend of larger-scale development.Large-scale pig farms employ standardized management,a high level of automation,and a strict_system.However,these farms have a large trading volume,and increased transmission intensity of FMD is noted inside the farm.At present,the main control measure against FMD is pig vaccination.However,a standard for immunization procedures is not available,and currently adopted immunization procedures have not been effectively and systematically evaluated.Taking a typical large-scale pig farm in China as the research subject and considering the breeding pattern,piggery structure,age structure and immunization procedures,an individual-based state probability model is established to evaluate the effectiveness of the immune procedure.Based on numerical simulation,it is concluded that the optimal immunization program involves primary immunization at 40 days of age and secondary immunization at 80 days of age for commercial pigs.Breeding boars and breeding sows are immunized 4 times a year,and reserve pigs are immunized at 169 and 259 days of age.According to the theoretical analysis,the average control reproduction number of individuals under the optimal immunization procedure in the farm is 0.4927.In the absence of immunization,the average is 1.7498,indicating that the epidemic cannot be controlled without immunization procedures.展开更多
Pig farming is becoming a key industry of China’s rural economy in recent years. The current pig farming is still relatively manual, lack of latest Information and Communication Technology (ICT) and scientific manage...Pig farming is becoming a key industry of China’s rural economy in recent years. The current pig farming is still relatively manual, lack of latest Information and Communication Technology (ICT) and scientific management methods. This paper proposes an industrial internet platform for massive pig farming, namely, IIP4MPF, which aims to leverage intelligent pig breeding, production rate and labor productivity with the use of artificial intelligence, the Internet of Things, and big data intelligence. We conducted requirement analysis for IIP4MPF using software engineering methods, designed the IIP4MPF system for an integrated solution to digital, interconnected, intelligent pig farming. The practice demonstrates that the IIP4MPF platform significantly improves pig farming industry in pig breeding and productivity.展开更多
This paper presents an economic viability analysis of two investment alternatives for a pig farming located in the city of Jatai, Goias State, Brazil. The first investment alternative consists of the implementation of...This paper presents an economic viability analysis of two investment alternatives for a pig farming located in the city of Jatai, Goias State, Brazil. The first investment alternative consists of the implementation of a biodigester, being the biogas burned in a flare. The second alternative also consists of a biodigester, nevertheless the produced biogas is used to generate electricity. The methodologies to estimate the methane production in anaerobic reactors are presented, as well as those for the quantification of the baseline and project emissions and of the electricity that can be generated. The results showed that the use of biogas for the electricity generation is the alternative more economically viable.展开更多
The management mode, economic benefits and technology integration of large-scale pig breeding are superior to those of traditional pig breeding by scattered peasant households, and it has a significant agglomeration e...The management mode, economic benefits and technology integration of large-scale pig breeding are superior to those of traditional pig breeding by scattered peasant households, and it has a significant agglomeration effect. However, the waste from large-scale pig farms are discharged in a concentrated manner, which aggravates environmental pollution and increases treatment difficulty, and improper disposal can lead to serious environmental problems. The main pollutants in the waste from large-scale pig farms are high-concentration organic pollutants, nitrogen and phosphorus. Meanwhile, they are also the main nutrients needed for the growth of plants, animals and microorganisms. By a series of key techniques, the waste from large-scale pig farms can be recycled as fertilizer, feed and energy.展开更多
China's extensive development model of pig industry gives rise to serious resource and environment bottleneck restriction,it is urgent to transform the existing development model into ecological farming model. In ...China's extensive development model of pig industry gives rise to serious resource and environment bottleneck restriction,it is urgent to transform the existing development model into ecological farming model. In this process,farmers' behavior will play a key role. On the basis of summarizing development connotation and characteristics of ecological agriculture,using survey data of 323 pig farmers in 6 provinces,based on the Theory of Planned Behavior( TPB) it introduced individual characteristics and external environment constraint variables,and made an empirical analysis on factors influencing intention and behavior of pig farmers' ecological farming using the Structural Equation Model( SEM). Results indicate:( i) ecological farming intention of pig farmers has the largest direct effect on their ecological farming behavior;( ii)ecological farming cognition of pig farmers has significant positive effect on their ecological farming behavior;( iii) external environment has the largest indirect effect on their ecological farming behavior,followed by the overall effect,and external environment has significant positive effect on ecological farming attitude and cognition of pig farmers;( iv) individual characteristics( educational level and income level) of pig farmers influence ecological farming behavior of pig farmers through their ecological farming attitude and intention,but the degree of influence is limited.展开更多
This study investigated antibiotics in pig feed and drinking water and their excretion together with manure and wastewater at a typical pig farm in Thailand.Among the 21 antibiotics analyzed,tetracyclines,macrolides,b...This study investigated antibiotics in pig feed and drinking water and their excretion together with manure and wastewater at a typical pig farm in Thailand.Among the 21 antibiotics analyzed,tetracyclines,macrolides,b-lactams,aminoglycosides,quinolones,sulfonamides,pleuromutilin,and florfenicol classes,were found as active ingredients in feed and drinking water and excreted together with pig wastes.Among them,doxycycline,tilmicosin,and amoxicillin were detected higher concentrations in wastewater(12.9e459.1 mg L^(-1)),sediment(0.074e0.62 mg kg^(-1)),and pig manure(0.45e4.1 mg kg^(-1)).During wastewater treatment,those major antibiotics were remaining in pond water and settled sludge up to 79.5 mg L-1 and 24.2 mg kg^(-1),respectively.The normalized excretion mass of total antibiotics was determined as 11.2 mg head-1 day-1,contributed mainly from doxycycline(5.9 mg head-1 day-1),tilmicosin(2.8 mg head-1 day-1),and amoxicillin(2.2 mg head-1 day-1).Based on total pig production in Thailand,the excreted mass of antibiotics was estimated at 79.3 tons year-1.展开更多
The study was carried out to evaluate the airborne gases and suspended particulate matter concentrations in the pig barns of a commercial pig farm situated in the peri-urban area of Beijing,China.The measurements foll...The study was carried out to evaluate the airborne gases and suspended particulate matter concentrations in the pig barns of a commercial pig farm situated in the peri-urban area of Beijing,China.The measurements followed the natural pig life-stages namely:gestation,farrowing,weaning,and fattening.In order to accomplish these objectives,three different measurement devices were employed:(i)color diffusion tubes,(ii)a portable gas measuring device,and(iii)a dust measuring instrument.Due to the rotation of the devices in the different sampling places,the measurements were performed at different time periods during the months of the summer and winter season in Beijing.The pig farm had a capacity of 15000 pigs per year and the manurial system was identified as“gan qing fen”or dry cleaning of the manure.The main by-products generated by the farm were irrigation water and small-scale biogas production.High dust concentrations were identified in the pig barns,especially during the feeding and manure cleaning events inside the farrowing and weaning barns with slatted floors.Inhalable dust ranged from 0 mg/m3 to 12.45 mg/m3,while the allowable dust ranged from 0 mg/m3 to 9.62 mg/m3.Ammonia concentration ranged from 0 ppm to 20 ppm(1 ppm=1 cm3/m3),and the carbon dioxide concentration ranged from 300 ppm to 8000 ppm.The highest ammonia concentration was recorded in the fattening barn during the summer season,while the highest carbon dioxide concentration was reported in the weaning barn during the summer season.The results of this study were similar to the results of studies performed on pig farms under natural and mechanical ventilation systems.On the other hand,the problems encountered during the gas measurements on the pig farm were directly related to the inadequate housing layout due to the obstruction of windows,fans and air channels for indoor ventilation,and thus the measurement devices faced harsh working conditions.Therefore,it is recommended that the housing system should be improved with repaired windows and curtains especially for the winter season;similarly,the repair of the fans should be attempted in order to improve the ventilation,especially in the gestation barns.展开更多
Small RNAs(sRNAs)are key players in the regulation of bacterial gene expression.However,the distribution and regulatory functions of sRNA in pig farm wastewater treatment plants(WWTPs)remains unknown.In this study,the...Small RNAs(sRNAs)are key players in the regulation of bacterial gene expression.However,the distribution and regulatory functions of sRNA in pig farm wastewater treatment plants(WWTPs)remains unknown.In this study,the wastewaters in anoxic and oxic tanks of the WWTPs were collected.The profiles of the community structure,mRNA expression,and sRNA expression of bacteria in pig farm wastewater were investigated using transcriptome sequencing and qPCR.This study demonstrated that there was a higher abundance of sRNA in the pig farm WWTPs and 52 sRNAs were detected.The sRNAs were mainly present in Proteobacteria and Firmicutes,including the potential human pathogenic bacteria(HPB)(Escherichia,Shigella,Bordetella and Morganella),crop pathogen(Pectobacterium)and denitrifying bacteria(Zobellella).And the sRNAs were involved in the bacterial functional activities such as translation,transcription,drug resistance,membrane transport and amino acid metabolism.In addition,most sRNAs had a higher abundance in anoxic tanks which contained a higher abundance of the genes associated with infectious diseases and drug resistance than that in oxic tanks.The results presented here show that in pig farm WWTPs,sRNA played an important role in bacterial function activities,especially the infectious diseases,drug resistance and denitrification,which can provide a new point of penetration for improving the pig farm WWTPs.展开更多
Covering the slurry pit has been shown to be one of the best ways to reduce ammonia emissions (NH<sub>3</sub>) during manure management. Yet, few studies have been conducted at farm scale. We studied the f...Covering the slurry pit has been shown to be one of the best ways to reduce ammonia emissions (NH<sub>3</sub>) during manure management. Yet, few studies have been conducted at farm scale. We studied the feasibility of three cover materials (peat, polystyrene balls and synthetic sheet roof) to reduce ammonia (NH<sub>3</sub>) emissions during on-farm storage of pig slurry. The impact on greenhouse gas emissions, methane (CH<sub>4</sub>), nitrous oxide (N<sub>2</sub>O) and carbon dioxide (CO<sub>2</sub>) of covering the slurry pit was also evaluated. Simultaneous field experiments were carried out using two similar pits at a farm with peat and polystyrene ball covers, which allowed direct comparison of the feasibility of the two covers to reduce gas emissions (measured using the dynamic chamber technique). Emissions from the third option (using a synthetic sheet roof) were estimated by measuring the concentrations in the headspace under the cover and the air leakage from the cover with a tracer gas (CO<sub>2</sub>). Results showed that the polystyrene balls cover reduced emissions of NH<sub>3</sub> during storage by up to 80% whatever the season, but increased potential greenhouse gas emissions by 20% in summer. No consistent reduction was achieved with the peat cover even though some individual results seemed to indicate up to 25% reduction in ammonia emissions;moreover, there was a 30% increase in CH<sub>4</sub> and CO<sub>2</sub> emissions during the storage period. The use of a synthetic sheet roof enabled up to 90% reduction in NH<sub>3</sub>, CH<sub>4</sub> and CO<sub>2</sub> emissions whatever the season.展开更多
文摘In order to understand the incidence reasons in a scaled pig farm of Guizhou Province, the infected pigs were diagnosed with epidemiological investigation, clinical observation, pathological diagnosis, enzyme-linked immunosorbent assay (ELISA), PCR/RT-PCR and bacterial isolation and identification. The results showed that the pigs were infected mixedly with classical swine fever virus (CSFV), pseudorabies virus (PRV) and E. coli. Therefore, some measures should be adopted to control the incidence of CSF, PR and colibacillosis in the pig farm.
基金Supported by the Fund Program of Jiangsu Academy of Agricultural Sciences(6111689)the Planning Program of"the Twelfth Five-year-plan"in National Science and Technology for the Rural Developme+nt in China(2015BAD12B04-1.2)the Fund for Independent Innovation of Agricultural Science and Technology of Jiangsu Province[CX(16)1006]~~
文摘The application model of epidemic disease assessment technology for Web-based large-scale pig farm was expounded from the identification of epidemic disease risk factors, construction of risk assessment model and development of risk assessment system. The assessed pig farm uploaded the epidemic disease risk data information through on-line answering evaluating questionnaire to get the immediate evaluation report. The model could enhance the risk communication between pig farm veterinarian, manager and veterinary experts to help farm system understand and find disease risk factors, assess and report the potential high risk items of the pig farm in the three systems of engineering epidemic disease prevention technology, biological safety and immune monitoring, and promote the improvement and perfection of epidemic disease prevention and control measures.
文摘Emergence of Chinese economy together with the current Livestock Revolution in Asia have led to an increase of meat demands, specially pork that is reflected in the growth of commercial pig farms in peri-urban areas of Beijing, capital of People's Republic of China. In the framework of the International Research Training Group and of the Sino-Project Recycling of Organic Residues from Agricultural and Municipal Origin in China, the status quo of a large pig farm is researched. The first phase of the project was focused on a detailed description of the nutrients and trace elements contained in the main inputs (water, feed) and outputs (manure, wastewater) of the pig farm. The compliance with the Chinese national standards or often referred to as GB standards (in Chinese "GuoBiao") and, current German recommendations were included. The analysis of nutrients and trace minerals followed the natural structure of the pig life cycle, i.e., gestation, farrowing, weaning and fattening. The main results showed that the pig drinking water met the recommendations for livestock drinking water, ground water and human drinking water. Concentrations of Zn, Cu, Mn and As in the pig feeds samples displayed higher values compared to the Chinese and German recommendations. Average values of trace elements in the pig manure did not surpass the Chinese and German recommendations of biowastes, however, some manure samples showed excessive concentrations of Cd, Cu and Zn. Likewise, Pb, Cd, Cr, Cu and Zn concentrations in the wastewater surpassed the recommendations for irrigation water.
基金supported by the National Key Research and Development Program of China(2016YFD0501501)the National Natural Science Foundation of China under Grant(11601292,61873154,11801398)+4 种基金Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province(20210009)General Youth Fund project in Shanxi Province(201901D211158)the 1331 Engineering Project of Shanxi Province,Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi Province(2019L0114)Key Projects of Health Commission of Shanxi Province(No.2020XM18)the Key Research and Development Project in Shanxi Province(202003D31011/GZ).
文摘Foot-and-mouth disease(FMD)is an acute,highly infectious and pathogenic animal disease.In recent years,with the rapid development of the swine breeding industry in China,pig farms have shown a trend of larger-scale development.Large-scale pig farms employ standardized management,a high level of automation,and a strict_system.However,these farms have a large trading volume,and increased transmission intensity of FMD is noted inside the farm.At present,the main control measure against FMD is pig vaccination.However,a standard for immunization procedures is not available,and currently adopted immunization procedures have not been effectively and systematically evaluated.Taking a typical large-scale pig farm in China as the research subject and considering the breeding pattern,piggery structure,age structure and immunization procedures,an individual-based state probability model is established to evaluate the effectiveness of the immune procedure.Based on numerical simulation,it is concluded that the optimal immunization program involves primary immunization at 40 days of age and secondary immunization at 80 days of age for commercial pigs.Breeding boars and breeding sows are immunized 4 times a year,and reserve pigs are immunized at 169 and 259 days of age.According to the theoretical analysis,the average control reproduction number of individuals under the optimal immunization procedure in the farm is 0.4927.In the absence of immunization,the average is 1.7498,indicating that the epidemic cannot be controlled without immunization procedures.
文摘Pig farming is becoming a key industry of China’s rural economy in recent years. The current pig farming is still relatively manual, lack of latest Information and Communication Technology (ICT) and scientific management methods. This paper proposes an industrial internet platform for massive pig farming, namely, IIP4MPF, which aims to leverage intelligent pig breeding, production rate and labor productivity with the use of artificial intelligence, the Internet of Things, and big data intelligence. We conducted requirement analysis for IIP4MPF using software engineering methods, designed the IIP4MPF system for an integrated solution to digital, interconnected, intelligent pig farming. The practice demonstrates that the IIP4MPF platform significantly improves pig farming industry in pig breeding and productivity.
文摘This paper presents an economic viability analysis of two investment alternatives for a pig farming located in the city of Jatai, Goias State, Brazil. The first investment alternative consists of the implementation of a biodigester, being the biogas burned in a flare. The second alternative also consists of a biodigester, nevertheless the produced biogas is used to generate electricity. The methodologies to estimate the methane production in anaerobic reactors are presented, as well as those for the quantification of the baseline and project emissions and of the electricity that can be generated. The results showed that the use of biogas for the electricity generation is the alternative more economically viable.
基金Supported by National Natural Science Foundation of China(41263006,2014BAC04B00)Program of Jiangxi Provincial Department of Science and Technology(20124ACB01200,20122BBG70086,20142BCB24009)Program of Jiangxi Academy of Sciences(JAS(2013)No.19-06,2016-YCXY-04,2013-XTPH1-14,2013H003)
文摘The management mode, economic benefits and technology integration of large-scale pig breeding are superior to those of traditional pig breeding by scattered peasant households, and it has a significant agglomeration effect. However, the waste from large-scale pig farms are discharged in a concentrated manner, which aggravates environmental pollution and increases treatment difficulty, and improper disposal can lead to serious environmental problems. The main pollutants in the waste from large-scale pig farms are high-concentration organic pollutants, nitrogen and phosphorus. Meanwhile, they are also the main nutrients needed for the growth of plants, animals and microorganisms. By a series of key techniques, the waste from large-scale pig farms can be recycled as fertilizer, feed and energy.
基金Supported by Project of National Natural Science Foundation(41171436)Key Project of National Social Science Foundation(14AZD002)
文摘China's extensive development model of pig industry gives rise to serious resource and environment bottleneck restriction,it is urgent to transform the existing development model into ecological farming model. In this process,farmers' behavior will play a key role. On the basis of summarizing development connotation and characteristics of ecological agriculture,using survey data of 323 pig farmers in 6 provinces,based on the Theory of Planned Behavior( TPB) it introduced individual characteristics and external environment constraint variables,and made an empirical analysis on factors influencing intention and behavior of pig farmers' ecological farming using the Structural Equation Model( SEM). Results indicate:( i) ecological farming intention of pig farmers has the largest direct effect on their ecological farming behavior;( ii)ecological farming cognition of pig farmers has significant positive effect on their ecological farming behavior;( iii) external environment has the largest indirect effect on their ecological farming behavior,followed by the overall effect,and external environment has significant positive effect on ecological farming attitude and cognition of pig farmers;( iv) individual characteristics( educational level and income level) of pig farmers influence ecological farming behavior of pig farmers through their ecological farming attitude and intention,but the degree of influence is limited.
基金the Office of National Higher Education Science Research and Innovation Policy Council via the Program Management Unit for Human Resource&Institutional Development,Research and Innovation(PMU-B),grant number B16F630088.
文摘This study investigated antibiotics in pig feed and drinking water and their excretion together with manure and wastewater at a typical pig farm in Thailand.Among the 21 antibiotics analyzed,tetracyclines,macrolides,b-lactams,aminoglycosides,quinolones,sulfonamides,pleuromutilin,and florfenicol classes,were found as active ingredients in feed and drinking water and excreted together with pig wastes.Among them,doxycycline,tilmicosin,and amoxicillin were detected higher concentrations in wastewater(12.9e459.1 mg L^(-1)),sediment(0.074e0.62 mg kg^(-1)),and pig manure(0.45e4.1 mg kg^(-1)).During wastewater treatment,those major antibiotics were remaining in pond water and settled sludge up to 79.5 mg L-1 and 24.2 mg kg^(-1),respectively.The normalized excretion mass of total antibiotics was determined as 11.2 mg head-1 day-1,contributed mainly from doxycycline(5.9 mg head-1 day-1),tilmicosin(2.8 mg head-1 day-1),and amoxicillin(2.2 mg head-1 day-1).Based on total pig production in Thailand,the excreted mass of antibiotics was estimated at 79.3 tons year-1.
基金The authors would like to thank the International Research Training Group of the University of Hohenheim and the China Agricultural University for their supportsThis study is part of the Sub Project 1.4“Evaluation of nutrient and pollutant cycles of livestock production systems and manure management systems in the North China Plain”+2 种基金The project is funded by the German Research Foundation(GRK 1070)the Ministry of Education(MOE)of the People’s Republic of ChinaThe authors also thank the fruitful cooperation with the Sino German Project:“Recycling of Organic Residues from Agricultural and Municipal Origin in China”,Sub Project 1:“Farm gate balance for animal production,”granted by the BMBF(FKZ 0330847A-H).
文摘The study was carried out to evaluate the airborne gases and suspended particulate matter concentrations in the pig barns of a commercial pig farm situated in the peri-urban area of Beijing,China.The measurements followed the natural pig life-stages namely:gestation,farrowing,weaning,and fattening.In order to accomplish these objectives,three different measurement devices were employed:(i)color diffusion tubes,(ii)a portable gas measuring device,and(iii)a dust measuring instrument.Due to the rotation of the devices in the different sampling places,the measurements were performed at different time periods during the months of the summer and winter season in Beijing.The pig farm had a capacity of 15000 pigs per year and the manurial system was identified as“gan qing fen”or dry cleaning of the manure.The main by-products generated by the farm were irrigation water and small-scale biogas production.High dust concentrations were identified in the pig barns,especially during the feeding and manure cleaning events inside the farrowing and weaning barns with slatted floors.Inhalable dust ranged from 0 mg/m3 to 12.45 mg/m3,while the allowable dust ranged from 0 mg/m3 to 9.62 mg/m3.Ammonia concentration ranged from 0 ppm to 20 ppm(1 ppm=1 cm3/m3),and the carbon dioxide concentration ranged from 300 ppm to 8000 ppm.The highest ammonia concentration was recorded in the fattening barn during the summer season,while the highest carbon dioxide concentration was reported in the weaning barn during the summer season.The results of this study were similar to the results of studies performed on pig farms under natural and mechanical ventilation systems.On the other hand,the problems encountered during the gas measurements on the pig farm were directly related to the inadequate housing layout due to the obstruction of windows,fans and air channels for indoor ventilation,and thus the measurement devices faced harsh working conditions.Therefore,it is recommended that the housing system should be improved with repaired windows and curtains especially for the winter season;similarly,the repair of the fans should be attempted in order to improve the ventilation,especially in the gestation barns.
基金financially supported by the Guangdong Technological Innovation Strategy of Special Funds(Key Areas of Research and Development Program,No.2018B020205003)
文摘Small RNAs(sRNAs)are key players in the regulation of bacterial gene expression.However,the distribution and regulatory functions of sRNA in pig farm wastewater treatment plants(WWTPs)remains unknown.In this study,the wastewaters in anoxic and oxic tanks of the WWTPs were collected.The profiles of the community structure,mRNA expression,and sRNA expression of bacteria in pig farm wastewater were investigated using transcriptome sequencing and qPCR.This study demonstrated that there was a higher abundance of sRNA in the pig farm WWTPs and 52 sRNAs were detected.The sRNAs were mainly present in Proteobacteria and Firmicutes,including the potential human pathogenic bacteria(HPB)(Escherichia,Shigella,Bordetella and Morganella),crop pathogen(Pectobacterium)and denitrifying bacteria(Zobellella).And the sRNAs were involved in the bacterial functional activities such as translation,transcription,drug resistance,membrane transport and amino acid metabolism.In addition,most sRNAs had a higher abundance in anoxic tanks which contained a higher abundance of the genes associated with infectious diseases and drug resistance than that in oxic tanks.The results presented here show that in pig farm WWTPs,sRNA played an important role in bacterial function activities,especially the infectious diseases,drug resistance and denitrification,which can provide a new point of penetration for improving the pig farm WWTPs.
文摘Covering the slurry pit has been shown to be one of the best ways to reduce ammonia emissions (NH<sub>3</sub>) during manure management. Yet, few studies have been conducted at farm scale. We studied the feasibility of three cover materials (peat, polystyrene balls and synthetic sheet roof) to reduce ammonia (NH<sub>3</sub>) emissions during on-farm storage of pig slurry. The impact on greenhouse gas emissions, methane (CH<sub>4</sub>), nitrous oxide (N<sub>2</sub>O) and carbon dioxide (CO<sub>2</sub>) of covering the slurry pit was also evaluated. Simultaneous field experiments were carried out using two similar pits at a farm with peat and polystyrene ball covers, which allowed direct comparison of the feasibility of the two covers to reduce gas emissions (measured using the dynamic chamber technique). Emissions from the third option (using a synthetic sheet roof) were estimated by measuring the concentrations in the headspace under the cover and the air leakage from the cover with a tracer gas (CO<sub>2</sub>). Results showed that the polystyrene balls cover reduced emissions of NH<sub>3</sub> during storage by up to 80% whatever the season, but increased potential greenhouse gas emissions by 20% in summer. No consistent reduction was achieved with the peat cover even though some individual results seemed to indicate up to 25% reduction in ammonia emissions;moreover, there was a 30% increase in CH<sub>4</sub> and CO<sub>2</sub> emissions during the storage period. The use of a synthetic sheet roof enabled up to 90% reduction in NH<sub>3</sub>, CH<sub>4</sub> and CO<sub>2</sub> emissions whatever the season.