Structure Design of Large-scale Fattening Pig House with Fermentation Bed

The fattening pig house with fermentation bed had an area of 2 100 m2, and the area of fermentation bed was 1 900 m2 with a utilization rate of 91.4%, which was 45% higher than that of conventional pig house with surrounding barrier. There was feeding trough around the house. The water troughs were set in the middle of the fermentation bed and of the feeding trough on the short sides of the house, separating feed and water. There were electric aluminum alloy shutters in both long sides of the house for ventilation, cooling and heat preservation. On both short sides, there were fans and wet curtains. The spray cooling devices were in- stalled outside the roof for cooling. The environmental control in the piggery, includ- ing light, temperature, water, humidity, carbon dioxide and ammonia, was realized to run by computer automatically. The coconut chaff and chaff configuration were used as mattress material, realizing the advantages of fermentation bed, such as no smell, zero emission, high-quality meat, saving labor, controlling disease, no drug residue, producing fertilizer, intelligent control, mechanized operation, etc.

Porcine Breeding Management in a Large-scale Piggery with Microbial Fermentation Bed

[Objective] The behavior of eating, drinking, defecating and peeing of 1 500 pigs in a large-scale microbial fermentation bed-equipped piggery was observed. We hoped to find some simple indicators that could reflect the health status of swinery and to provide experience for the swinery performance management in large-scale microbial fermentation bed-equipped piggery. [Method] The body weight （BW）, daily BW gain, feed intake and other indicators of different-day-old pigs were recorded in details. Based on the recorded data, the models between BW, BW gain, average daily feed intake and feed/gain ratio and growth days （d） were established. In addition, the incidences of pox-like macula （dermatitis）, diarrhea （gastrointestinal disease）, cough （respiratory disease）, stiff pig （malnutrition）, conjunctivitis （eye disease） and foot inflection （trauma） among fattening pigs were also investigated. [Result] The BW range, average BW, daily BW gain, breeding days, daily feed intake range, average daily feed intake, staged feed intake, accumulated feed intake, feed/gain ratio and accumulated feed/gain ratio of different-day-old pigs were studied, respectively. Four dynamic models were established for the growth of pigs： （1） the BW （y）-age （x） mod- el： y=0.758 9x-19.883 （3=0.993 7）; （2） the BW gain （y）-age （x） model： y=1.039 5x05051 （F=0.885 4）; （3） the average daily feed intake （y）-age （x） model： y=0.023 5x-0.334 3 （F=0.991 7）; （4） the feed/gain ratio （y）-age （x） model： y=0.022x＋0.427 8 （P=0.988 5）. Based on these models, the corresponding theoretical growth value of pigs at different growth stage could be predicted. The main diseases occurred among the swinery in the large-scale microbial fermentation bed piggery included pox-like macula （dermatitis）, diarrhea （gastrointestinal disease）, cough （respiratory disease）, stiff pig （mal- nutrition）, conjunctivitis （eye disease） and foot inflection （trauma）. The deadly infec- tious diseases had been not found among the pigs. [Conclusion] When the actual BW, BW gain, average daily feed intake and feed/gain ratio were all lower than the theoretical values predicted by the models, the management should be enhanced. The average daily feed intake of 60 to 65-day-old pigs was lower than the theoretic value, indicating that the pigs could not adapt nicely to the fermentation bed at the very early stage. When the pigs grew up to 70 to 75 d old, the average daily feed intake was higher than the theoretical value, indicating that the pigs had adapted to the fermentation bed. In particularly, average daily feed intake of 75-day-old pigs was higher than the theoretical value by 21%. It was suggested the fermentation bed was conducive to the growth of pigs. Considering the occurrence of diseases among pigs, the overall incidence was relatively low. The incidence of each disease was all lower than 10% with little difficulty in treating. If the management of mattress was strength- ened, such as paying attention to feeding and keeping water clean, many diseases could heal by themselves.

Barrier Structure Design for Fattening Pigs in Large-scale Pig House with Fermentation Bed

[Objective] The large-scale single-column fattening pig house with fermen- tation bed could hold 1 500 heads of fattening pigs. Since the number of pigs in piggery is too large, the management is difficult. The behavior of feeding, drinking, movement, sleeping, fighting of pigs is difficult to handle. The pigs cannot be man- aged well, resulting in the enhanced weakness of piglets, enhanced illness of weak pigs and missing treatment of ill pigs. The management for the pig populations is not satisfactory, and thus, it is needed to improve timely. [Method] The barriers for the fattening pigs in the large-scale pig house with fermentation bed were designed. The single management for single fattening pig was proposed. The large-scale fat- tening pig house was divided into 8 regions. Among them, 4 regions were located in both sides of the fermentation bed. Their main function was to separate ill, weak, small and bad pigs. In addition, the main column was divided into 4 gradual barri- ers. They were used to separate different-size fattening pigs. In view of manage- ment, the different-type pigs were managed dividedly with the gradual barriers. The equally-sized pigs were concentrated into one column. The ill, weak, small and bad pigs were isolated into barriers. Thus, the dynamic management was adopted. Until the fattening pigs grew up to 75 kg and their health was stable, the barriers among the columns were canceled to mix the pigs again and guarantee the pigs more gymnastic space. [Result] This design would improve the disease resistance of ill pigs, health status of weak pigs and management level of pig populations. This study would also provide a basis for the healthy running of large-scale fattening pig house with fermentation bed. [Conclusion] The pig-raising model with fermentation bed would improve the environment of pig house and the welfare of pigs. In addi- tion, the performance of pigs and quality of pork were also improved. The fermen- tation bed had an obvious advantage in safety and economics, and it had a broad application prospect.

Design of Environmental Monitoring and Control System for Large-scale Pig House with Fermentation Bed

The design and assembly of environmental monitoring and control system for large-scale pig house with fermentation bed helped to solve the problem of environmental automatic control in piggery.The sensors would monitor the temperature,humidity,light,wind direction,wind speed,CO2,NH3and other parameters.On-line real-time data collection was achieved.The expert system was constructed to control the temperature in piggery below 30℃,to control the air and mattress humidities higher than 65%.Under the conditions of different season or different wind speed,even in day and night,the control actuators were different.The actuators included fanning wet curtain,lighting,micro spraying,spraying,propeller fan,electric aluminum alloy shutter and spraying systems on the roof.The actuators were integrated,and they control the piggery environment simultaneously.The system also designed the remote video monitor interface,parameter-monitoring curved interface and operation interface,which provided a good man-machine interface.

Piglets Behavior Characteristics under Breeding Mode of Microbial Fermentation Bed

[Objective] This experiment aimed to compare piglets behavior under microbial fermentation bed breeding mode and traditional rearing mode. [Method] Pig behavior＇s statistical analysis under both microbial fermentation bed pig breeding mode and traditional rearing mode was se lected to study the effect of different breeding environment on pig＇s growth [ Result] The results showed that the duration of piglets lying and sleeping behavior accounted for the highest proportion of tested behavior, up to more than 70% ,followed by feeding and drinking which reached 15.96% （under microbial fermentation bed breeding mode） and 9.33% （under traditional rearing mode） respectively. Compared with traditional intensive rearing mode, piglet exploratory behavior＇s occurrence probability and duration increased significantly, by 28.62% and 12.21% respectively. Fighting behavior＇s occurrence probability and duration decreased significantly, by 49.83% and 91.26% respectively. Nutrient index and health index were introduced to evaluate piglet＇s general heath condition under microbial fermentation bed breeding mode, and results indicated that the health index of piglets under microbial fermentation bed breeding mode had slight difference from that under traditional mode, namely 10.83 and 10.03 respectively. But health index of piglets under microbial fermentation bed breeding mode was 245.12, much higher than 21.96 under traditional mode. [ Conclusion] Piglets would be healthier under microbial fermentation bed breeding mode.

Effects of Spent Mushroom Substrate of Pleurotus eryngii as Fermentation Bed Padding on Growth Performance, Intestinal Microflora and Immunity of Weaning Piglets

[Objective] The paper was to examine the effects of spent mushroom substrate of Pleurotus eryngii as fermentation bed padding on growth performance, intestinal microflora and immunity of weaning pigs. [Method] A total of 120 weaning piglets （DurocxLandracexYorkshire） with the average initial body weight of （8.0±0.5） kg were allocated to five dietary treatments in a randomized complete block design for 42 d, each of which was replicated three times with eight piglets per replicate （ half male and half female）. The padding for control group was 50% sawdust ＋50% rice husk; experimental group I, 100% spent mushroom substrate; experimental group II, 15% sawdust ＋15% rice husk ＋70% spent mushroom sub- strate; experimental group III, 25% sawdust ＋25% rice husk ＋50% spent mushroom substrate; and experimental group IV, 35% sawdust ＋35% rice husk ＋30% spent substrate. [Result] Except for experimental group IV, the other three experimental groups had higher average daily gain compared to the control group （P〈0.05）. The average daily feed intake in experimental group I increased obviously compared to the control group（P〈0.05）. Except for experimental group I, the diarrhea rate of weaning piglets in experimental groups II, III and IV significantly decreased compared to the control group（P〈0.05）. The number of lactobacilli and bifidobacteria in colon and cecum in experimental groups I, II and III increased distinctly （P〈 0.05）, while the number of Escherichia coli and Salmonella decreased remarkably compared to the control group （P〈0.05）. The positive rates of T and B lymphocytes in peripheral blood of weaning piglets in four experimental groups were significantly higher than that in control group at 21 and 42 d post weaning （P〈0.05）. The IgA content of intestinal mucous in piglets was significantly improved in experimental groups II and III （P〈0.05）. [Conclusion] It enhances the production performance when improving immunity and reducing diarrhea rate of piglets by using spent mushroom substrate of P. eryngii as the fermentation bed padding. Experimental group III （25% sawdust ＋25% rice husk ＋50% spent mushroom substrate） is the optimal proportion of spent mushroom substrate.

Effects of Compound Microbial Inoculants on Fermentation Bed of Swine

[Objective] The aim was to study the effects of compound microbial inoculants on fermentation bed.[Method] With fermentation simulated in lab,analysis was conducted on changes of temperature,pH,nitrate nitrogen,ammonium nitrogen,urease activity and protease activity in fermentation by microorganism and natural fermentation respectively,to explore effects of compound microbial inoculants on fermentation bed of swine.[Result] Compared with control group,the added microbial inoculants in test group promoted temperature rising during fermentation and prolonged lasting period of high temperature,for example,high temperature at 60 ℃ maintained 10 d in the test.Furthermore,the inoculants reduced pH of packaging material environment,for example,pH finally was 7.05,lower than that of control group.Microbial inoculants accelerated transformation of ammonium nitrogen into nitrate nitrogen and reduced nitrogen loss.In addition,activities of urease and protease enhanced in packaging materials and excrements degraded rapidly.[Conclusion] The research provides technical references for strain development,selection and evaluation of fermentation bed of swine.

Effects of Fermentation Bed Padding on Intestinal Flora,Serum Biochemical Indexes and Immune Function of Growing-finishing Pigs

[Objective]The paper was to study the effects of fermentation bed padding on intestinal flora,serum biochemical indexes and immune function of growing-finishing pigs.[Method]A total of 90 growing-finishing pigs(Duroc × Landrace × Yorkshire)with the body weight of(30.5±0.8)kg were randomly divided into five groups,three replicates each group,six pigs each replicate.The padding of five groups were:50%rice husk+50%sawdust(control group),100%spent mushroom substrate of Pleurotus eryngii(100%spent mushroom substrate group),15%rice husk+15%sawdust+70%spent mushroom substrate(70%spent mushroom substrate group),25%rice husk+25%sawdust+50%spent mushroom substrate(50%spent mushroom substrate group),35%rice husk+35%sawdust+30%spent mushroom substrate(30%spent mushroom substrate group).The pre-trial lasted 7 d,and the formal trial lasted 90 d.[Result]Compared with the control group,the number of Escherichia col in 100%,70%and 50%spent mushroom substrate groups decreased by 35.4%,24.0%and 20.8%,respectively(P<0.05);the number of salmonella successively decreased by 29.4%,19.3%and 15.2%,respectively(P<0.05);the number of lactobacillus successively increased by 21.7%,15.9%and 12.2%,respectively(P<0.05);and the number of bifidobacteria successively increased by 20.2%,16.7%and 11.8%,respectively(P<0.05).Compared with the control group,the total serum protein content in 100%,70%,50%and 30%spent mushroom substrate groups increased by 30.6%,33.0%,28.0%and 18.4%,respectively(P<0.05);and the serum urea nitrogen content decreased by 32.4%,34.5%,33.9%and 22.0%,respectively(P<0.05).There was no significant difference in serum albumin,aspartate aminotransferase(AST)and alanine aminotransferase(ALT)between treatment groups and control group.The IgA,IgG,IgM and IL-6 levels in serum of each treatment group were significantly different from those of the control group(P<0.05).There was no significant difference in IgA,IgG,IgM and IL-6 levels among 100%,70%and 50%spent mushroom substrate groups.[Conclusion]It improves the balance of intestinal microecological flora of growing-finishing pigs and enhances the immune performance of pigs by using spent mushroom substrate of P.eryngii as the fermentation bed padding.15%rice husk+15%sawdust+70%spent mushroom substrate is the optimal proportion of spent mushroom substrate for growing-finishing pigs.

Effects of Fermentation Bed Cultivation Model on the Expression Amount of MSTN in Swine Gluteus and Its Correlation with Pork Quality

[ Objective] The research aimed to discuss the differences of the expression amount of the related gene that regulated the development of muscles under different feeding environments. [ Method ] Using fluorescence quantitative PCR, the effects of fermentation bed cultivation model on the expression mount of MSTN in pig gluteus were studied and the correlation between its expression amount and the carcass quality of pig was analyzed. [ Result] The relative expression amount of MSTN mRNA of swine gluteus under fermentation bed cultivation model decreased 8.6% by that under conventional cement ground feeding model, but there was no significant difference（P 〉0.05）. The expression amount of MSTN mRNA in pig gluteus undo＂ conventional cement ground feeding model showed a significant negative correlation with shear force （ P 〈 0.05）. The expression amount of MSTN mRNA in pig gluteus under fermentation bed cultivation model showed significant negative correlations with water content and muscle fiber diameter（P 〈 0.05 ）. The expression amount of MSTN mRNA in pig gluteus under two cultivation models had no significant correlation with other meat quality indices（P 〉 0.05）. [ Conclusion] The research could provide test materials for the studies on the regulation of pork quality.

Effect of Fermentation Bed with Spent Mushroom Substrate of Pleurotus eryngii on Weaning Piglets

[Objective] The paper was to investigate effects on fermentation bed temperature,growth performance,diarrhea rate and digestive en-zyme activity of weaning piglets by using spent mushroom substrate of Pleurotus eryngii as padding.[Method] A total of 120 weaning piglets（Duroc × Landrace ×Yorkshire） with average initial body weight of（8.0 ±0.5）kg were allocated to five dietary treatments in a randomized complete block design for 42 d,each of which was replicated three times with eight piglets per replicate（half male,half female）.The padding for control group was（50% sawdust ＋50% rice husk）;experimental group Ⅰ 100% spent mushroom substrate;experimental group Ⅱ（15% sawdust ＋15% rice husk ＋70% spent mushroom substrate）;experimental group Ⅲ（25% sawdust ＋25% rice husk ＋50% spent mushroom substrate）;experimental group Ⅳ（35% sawdust ＋35% rice husk ＋30% spent substrate）.[Result] There was no significant difference in surface temperature of fermentation bed between experimental groups and control group（P〉0.05）.Compared with the control group,the temperature under 20 cm of fermentation bed in ex-perimental groups I,Ⅱ and Ⅲ increased significantly（P〈0.05）.Except for experimental group Ⅳ,other three experimental groups had higher aver-age daily gain（P〈0.05） and experimental group Ⅰ had higher average daily feed intake（P〈0.05） compared to the control group.The diarrhea rate and mortality of weaning piglets in experimental groups Ⅱ,Ⅲ and Ⅳ were significantly decreased compared with the control group（P〈0.05）.Compared with the control group,other three experimental groups had higher digestive enzyme activity in duodenal contents except for experimental group Ⅳ（P〈0.05）.[Conclusion] Spent mushroom substrate of P.eryngii can be used as fermentation bed padding,and the optimal proportion was experimental group Ⅲ.

Structure Design of Large-scale Sow House with Fermentation Bed

ln this research, the whole contact-type large-scale sow house with fer-mentation bed was designed. The planning area of the entire piggery was 5 700 m2 with workplace and green belts. The sow house was 93 m long and 33 m wide, a total of 3 069 m2, including office area of 60 m2 and aisle area of 107 m2. The fer-mentation bed had an area of 2 902 m2 with length of 88.7 m and width of 27.7 m. lts area accounted for 95% of the total area of sow house. The fermentation mattress had a depth of 80 cm, and had a volume of 2 321 m3, equivalent to 733 t of coconut chaff and rice chaff. On a large fermentation bed, the areas for boars, replacement gilts, pregnant sows, obstetric tables, nursery pigs, etc. were designed. The large-scale sow house with fermentation bed was equipped with the automatic feeding system, automatic sprinkler system, automatic positioning column for preg-nant sows, sows＇ obstetric table system, fanning wet curtain cooling system, video monitoring system, environmental monitoring （light, temperature, water, humidity, CO2, NH3） and automatic control system. Every farming area was equipped with feeding trough and water trough. The water though was fixed with overflow pipe for removing the extra water. The house could hold 500-head sows. Each sow occu-pied 4.9 m2 of the fermentation bed in average. The designed sow house had a maximum annual output of 10 000 piglets.

Study on Temperature Gradients and Protein Enrichment by <i>Aspergillus oryzae</i>in Solid-State Fermentation on Packed Bed Bioreactor Using Jowar (Sorghum) Straw as Substrate

The packed bed solid state bioreactor designated as PBSSB is constructed in the present study. The experiments are carried out in packed bed bioreactor with jowar straw and inoculated with Aspergillus oryzae. Temperature gradient has been measured at different axial positions. It is found that the organisms grew rapidly during the period from 20 to 30 h during which heat generation is more. These results are in agreement with other researchers. The fermented jowar straw shows threefold increase in protein content. This can be utilized as high value nutritional feed to animals.

Succession of bacteria communities during production and application of dairy bedding by membrane-covered aerobic fermentation

The cost of dairy manure treatment and bedding material purchase increases the operating cost of the dairy farm.Membrane-covered aerobic fermentation system has been widely used for dealing with dairy manure and recycling the final product as bedding material.However,the microbial safety in each processing step is still uncertain.To better understand the bacterial community dynamics during the whole bedding conversion process,a full-chain and large-scale experiment including 16-day membrane-covered aerobic fermentation and 11-day bedding material application was conducted.The results showed that the pile temperatures in the fermentation stage rapidly increased to 80°C and maintained>50°C for more than 11 days and the use of fermentation product as bedding material provided cows with a stable and comfortable bedding environment.The Chao1 and Shannon index decreased at the end of the fermentation stage and remained stable in the application stage,indicating that membrane-covered aerobic fermentation effectively killed some pathogenic bacteria and guaranteed both the maturity and stability of the final product.The dominant bacteria in the fermentation stage were Acinetobacter,Thermus,and Rhodothermus at genus level.Seven common potential pathogens of mastitis(Staphylococcus,Enterococcus,Serratia,Pseudomonas,Corynebacterium,Mycobacterium,and Bacillus)were found at the end of fermentation stage but the relative abundance was low(0.0025%-0.2727%).The dominant bacteria in the application stage mainly included Acinetobacter,Pseudomonas,and Flavobacterium at the genus level.The relative abundance of Pseudomonas increased in the application stage,which was a reminder to the dairy farm to pay attention to the disinfection and timely replacement of bedding material to prevent the occurrence of dairy mastitis.The results of this study contributed deep understanding of the microorganism-driven bedding conversion process and provide practical guidance and cautions for the bedding materials application.

微生物发酵床养猪垫料研制番茄育苗基质的效果分析

为了实现废弃资源的资源化利用,使用微生物发酵床养猪垫料研制番茄育苗基质,选取使用1年的微生物发酵床养猪垫料,提取其浸提液并稀释成不同浓度,以番茄种子萌发情况为指标,筛选基质中垫料适宜添加量,并通过穴盘育苗试验确定基础基质配方,进一步优化N、P、K用量,最终确定番茄育苗基质配方。结果表明:利用微生物发酵床养猪垫料研制番茄育苗基质的配方为垫料︰椰糠=3︰7(体积比),N用量0.3 kg·m^(−3)、P用量0.2 kg·m^(−3)、K用量0.1 kg·m^(−3);用该基质进行番茄育苗,出苗率达98%,幼苗的株高、茎粗、根长均显著优于市售草炭基质(对照);所繁育的幼苗移栽田间种植,其田间番茄苗的株高和挂果数均显著优于对照。番茄育苗基质的研制可实现微生物发酵床养猪垫料的资源化利用。

发酵床对哺乳期湖羔羊生长、消化以及血液理化特性的影响

针对目前养羊业中羔羊哺乳期腹泻和死亡高发的瓶颈难题,本试验将素土地面改造成发酵床,通过检测不同季节(冷季、温季和热季)发酵床的温度以及哺乳期羔羊腹泻率、生长、消化、血液理化等指标,研究羔羊哺乳初期采用发酵床饲养的效果。每个季节选择连续3批新产双羔的湖母羊(30只·批^(-1))及随母哺乳的羔羊,随机分到两栋建筑结构完全相同的羔羊舍,其中一栋舍采用发酵床(锯末∶稻壳=7∶3),另一栋舍为传统的素土地面,单栏饲养,饲养7 d后将所有羊转入半开放舍(素土地面)继续饲养至断奶(60 d)。结果表明:1)各季节发酵床表层温度均显著高于素土地面(P<0.05),尤其冷季,各时段分别较素土地面提高1.80(早)、0.97(午)和1.09℃(晚)。2)冷季和温季的各试验期(60 d)发酵床组羔羊的腹泻率均显著低于素土地面组(P<0.05),分别降低19.99%和28.09%,且羔羊日增重(ADG)分别提高15.04%和7.88%,但热季期两组羔羊的腹泻率和ADG差异均不显著(P>0.05)。3)冷季期羔羊出生7 d内采用发酵床饲养显著提高了羔羊断奶期的干物质、粗蛋白、粗脂肪和钙表观消化率(P<0.05),而热季期各种养分的表观消化率两组间均未达到显著差异(P>0.05)。4)从血液理化指标上,冷季期发酵床组羔羊的血清葡萄糖(GLU)、白蛋白、球蛋白含量以及全血中淋巴细胞百分比均显著高于素土地面组(P<0.05),温季期发酵床组的GLU含量也显著高于素土地面组(P<0.05),而热季期各项理想指标两组均未表现出显著性差异(P>0.05)。可见,出生一周内的哺乳羔羊在冷季和温季采用发酵床饲养模式可有效改善羔羊的生长和消化性能。

奶牛场厌氧发酵牛粪生产垫料工艺中菌群变化的研究

【目的】探究奶牛场粪污厌氧发酵生产垫料工艺过程中菌群的变化,为奶牛场牛粪垫料标准化生产和合理安全使用提供理论参考。【方法】采集4个规模化奶牛场中粪污厌氧发酵前牛粪、厌氧发酵固液分离后的牛粪及牛卧床上的牛粪垫料,提取菌体DNA进行16S rRNA高通量测序,对于不同阶段的微生物多样性、菌群组成及显著差异的特征菌群进行分析。【结果】与发酵前牛粪相比,经过厌氧发酵固液分离后的牛粪中菌群多样性和丰富度均降低,但与牛粪垫料菌群多样性和丰度相似。发酵前牛粪中丰度最高的菌门和菌属分别为厚壁菌门(Firmicutes,55.15%)和瘤胃菌科UCG-005菌属(UCG-005,16.68%),厌氧发酵固液分离后牛粪中丰度最高的菌门和菌属分别为厚壁菌门(48.12%)和芽孢杆菌属(Bacillus,12.16%),牛粪垫料中丰度最高的菌门和菌属分别为放线菌门(Actinobacteriota,37.02%)和谷氨酸杆菌(Glutamicibacter,11.65%)。通过LEfSe分析发现,发酵前牛粪、厌氧发酵固液分离后牛粪及垫料3组间存在显著差异的菌属共有14种。【结论】通过对奶牛场厌氧发酵牛粪生产垫料过程中菌群组成的研究,发现优势菌门和菌属均发生了较大改变,发酵处理后菌群多样性和丰富度均降低,该种生产工艺完全满足奶牛场对牛粪垫料安全性的需要。

熟化垫料部分替代化肥对水稻–多花黑麦草轮作生产力、土壤肥力和重金属含量的影响

探讨熟化垫料部分替代化肥对长江中下游地区水稻–多花黑麦草轮作系统生产力、土壤肥力和重金属含量的影响,为长江中下游地区有机肥合理施用及其风险评估提供科学依据。采用连续2年的大田小区试验,以猪发酵床熟化垫料不同比例替代化肥:不施肥对照(CK)、单施化肥(T1)、熟化垫料替代25%化肥氮(T2)、熟化垫料替代50%化肥氮(T3)、熟化垫料替代75%化肥氮(T4)、单施熟化垫料(T5),分析在相等施氮量条件下熟化垫料替代化肥对水稻–多花黑麦草轮作系统作物地上生物量、氮素利用率、土壤理化性质以及重金属含量的影响。研究结果表明,与对照相比,各施肥处理均能不同程度地提高水稻籽粒、水稻秸秆、多花黑麦草产量及地上部周年总产量。在不同比例熟化垫料替代处理中,随着熟化垫料替代比例的增加,作物产量表现为降低的趋势。相对于T1处理,T2处理的水稻–多花黑麦草轮作系统地上部周年生物产量连续两年分别提高5.88%和6.40%,T3处理差异不显著,T4和T5处理显著降低。随着熟化垫料施用比例的增加,水稻–多花黑麦草轮作系统作物年总产量呈先增加后降低趋势,其中T4和T5处理的周年地上部总产量第2年比第1年分别增加11.49%和20.34%。施肥显著影响轮作系统作物的氮素吸收量、利用率和偏生产力。相比于T1处理,T2处理第1年和第2年轮作系统地上部氮素吸收量分别增加9.387%和7.59%,氮素利用率分别提高14.66%和10.14%,偏生产力分别提高7.58%和5.94%;T3处理与T1处理差异不显著;但T4和T5处理3个指标均显著降低。相比于T1处理,耕层0~20 cm土壤p H、有机质、速效钾和有效磷含量随着熟化垫料替代比例的增加表现为升高的趋势。相比于T1处理,T3、T4和T5处理的土壤有机质含量,分别增加33.98%、46.23%和47.09%,有效磷含量分别增加49.11%、67.15%和73.87%,速效钾含量分别增加23.36%、36.77%和55.24%(2年均值)。熟化垫料施用造成了土壤Cu和Zn的富集,但对土壤Cd含量影响不显著,同一施肥处理土壤中的Cu、Zn和Cd含量,第1轮作年低于第2轮作年,但含量均在土壤环境质量农用地土壤污染风险管控标准(GB15618—2018)范围内。2年4季定位试验表明,熟化垫料替代25%~50%化肥为长江中下游地区水稻–多花黑麦草轮作生产值得推荐的化肥减量增效模式。

畜禽粪污异位发酵床处理残渣组成特征研究

异位发酵床是处理畜禽粪污的常用技术,目前针对异位发酵床的研究基本是在半年以内的短期跟踪,对于一年以上异位发酵床处理后残渣的组成特征及利用潜力仍不清楚,限制了发酵后残渣的处理和资源化利用。本研究选择浙江省3个典型养猪场,采集了畜禽粪污经异位发酵床处理半年(S1组)、1年(S2组)及2年(S3组)剩下的残渣,采用微生物高通量测序、色谱分离结合常规理化指标测试,对异位发酵床发酵剩余残渣中的微生物、无机物、重金属及有机物组成和含量进行测定,并据此评估了残渣的土地利用潜力。结果表明:长期运行下异位发酵床物料微生物趋于一致,S2组和S3组具有相似的微生物群落组成。发酵过程每日的翻抛有利于粪污中氮的转化,三组样品中溶解态NH_(4)^(+)含量均显著低于NO_(3)^(-)和NO_(2)^(-)含量;经长时间发酵,有机物降解后,无机物累积,残渣中无机盐含量增加,但其总电导率均低于3000μS/cm,处于植株安全生长范围;畜禽粪污的长期投加,有机物降解为可挥发的二氧化碳和水,重金属却只能被保留在发酵床中,不断富集和累积,但残渣中重金属含量仍低于《有机肥料》(NY/T525-2021)浓度限值,满足有机肥制作标准。三维荧光光谱及色谱分析显示,S1组和S2组残渣中腐殖质组分种类多,且含有多种小分子有机组分,而发酵2年的S3组残渣中腐殖质种类少、分子量大、结构更加单一稳定。本研究揭示了畜禽粪污长期异位发酵床处理后残渣组成特征及土地利用潜力,即经异位发酵床长期处理的畜禽粪污部分指标无法满足《畜禽粪污还田技术规范》(GB/T 25246-2010),因此无法直接还田施用,但能满足《有机肥料》(NY/T 525-2021),可制成有机肥料后还田,这为长期异位发酵床残渣的后续处理和资源化利用提供了参考。

异位发酵床垫料水分蒸发试验

【目的】探究异位发酵床发酵温度、初始含水率、空气温度和湿度等对异位发酵床垫料水分蒸发的影响。【方法】选择谷壳、使用1个月的异位发酵床垫料以及使用半年的异位发酵床垫料3种试样,利用水浴锅给垫料持续加热来模拟垫料发酵产热,通过恒温恒湿箱控制空气温、湿度,采用单因素试验和响应面试验对垫料水分蒸发的影响因素进行分析。采用多元线性回归方法,得到3种垫料的水分蒸发量与发酵温度、初始含水率、空气温度和湿度的回归模型,在相应条件下预测发酵床的水分蒸发量。【结果】(1)发酵温度、初始含水率、空气温度和湿度对发酵床运行过程中垫料水分蒸发量的影响均显著;(2)当发酵温度一定时,随着空气温度的升高,异位发酵床垫料的水分蒸发量呈先增多后减少的变化趋势;(3)在发酵温度70℃、初始含水率75%、空气温度25℃、空气湿度70%的条件下3种垫料的水分蒸发量均达到最大值。【结论】当试样为谷壳和使用1个月的异位发酵床垫料时,发酵温度、初始含水率、空气温度和湿度对发酵床运行过程中水分蒸发量的影响达到极显著水平(P<0.01);当试样为使用半年的异位发酵床垫料时,发酵温度、初始含水率、空气温度对水分蒸发量的影响达到极显著水平(P<0.01),空气湿度对水分蒸发量的影响达到显著水平(P<0.05)。

漏缝地板发酵床对育肥羊养殖气体排放的影响及微生物学机理

为明确漏缝地板发酵床对育肥羊养殖过程氨(NH_(3))和温室气体排放特征的影响机制,本研究设置地面和漏缝地板发酵床两个试验处理,测定分析了育肥羊养殖过程NH_(3)、氧化亚氮(N2O)、二氧化碳(CO_(2))和甲烷(CH4)的排放特征,并采用宏基因组学解析了影响上述气体排放的微生物学机理。试验结果表明,与地面相比,漏缝地板发酵床能够显著降低育肥羊养殖过程的NH_(3)排放(P<0.05),其NH_(3)排放速率为21.64~58.92 mg·m^(-2)·h^(-1),NH_(3)累积排放量为86.36±1.06 g·m^(-2),减排率达58.60%。漏缝地板发酵床同样也能显著降低育肥羊养殖过程的CH4排放速率(P<0.05),其CH4累积排放量为26.66 g·m^(-2),减排率可达64.42%。然而,漏缝地板发酵床会使得育肥羊养殖过程的N2O和CO_(2)排放显著升高(P<0.05),尤其是发酵床组的N2O累积排放量高达994.30 mg·m^(-2),为地面的190.84倍。宏基因组学分析结果表明,发酵床粪便中Salinicoccus、Corynebacterium、Brachybacterium和Nocardiopsis等具有耐盐特性并参与硝化、反硝化的有益微生物相对丰度显著升高(P<0.05),hcp、narG、nirK、norB、nosZ等氮转化关键基因相对丰度显著升高(P<0.05),这使得发酵床的NH_(3)排放降低,但会造成较高的N2O排放。发酵床中的Atopostipes和Anaerococcus等厌氧微生物相对丰度显著降低(P<0.05),导致了其较低的CH4排放。此外,发酵床较高的CO_(2)排放主要与微生物的丙酮酸代谢、三羧酸循环等密切相关。