Construction of Risk Assessment Application Model of Epidemic Disease in Large-scale Pig Farms

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.

Construction and Environmental Protection of Large-scale Livestock and Poultry Farms

Large-scale breeding of livestock and poultry is the main way of modern animal husbandry development.This breeding method is widely used by the majority of owners because of its easy technical promotion,low breeding cost and good economic benefits.But with the development of large-scale livestock and poultry breeding,the pollution and damage to the environment caused by fecal pollution from large-scale livestock and poultry breeding has been criticized by many environmentalists.In this paper,through visit and investigation of large-scale livestock and poultry farms,the methods and measures of environmental protection in the construction of large-scale livestock and poultry farms are proposed.

Occurrence of Multi-Drug Resistant <i>Listeria species</i>in Faecal Samples of Poultry Chickens in Rural Farms in Lagos State, Nigeria

Background: Listeriosis is a common zoonotic disease caused by a foodborne pathogen, Listeria monocytogenes. Poultry meat and products have been established as vehicles of transmission of pathogenic Listeria strains to humans. This study evaluates the occurrence of Listeria species in faeces of poultry chicken in Lagos. Methods: One hundred and fourteen pooled fresh faecal samples from cage-reared broiler chickens were collected from 12 farms in three rural areas in Lagos State from May to August 2019. All samples were analysed for Listeria species detection according to ISO11290-1 standard and confirmed using PCR assay. Susceptibility testing was performed using the Kirby-Bauer disc diffusion technique. Results: Twenty-eight (24.6%) Listeria species were detected from 114 faecal samples. The isolated Listeria species were L. monocytogenes 8 (7.0%), L. ivanovii 9 (7.9%), L. grayi 7 (6.1%) and L. innocua 4 (3.5%). There was no significant difference in the frequency of occurrence of Listeria species across the different locations (X2 = 4.98, p = 0.08). The listeria species were susceptible to Augmentin (96.4%), vancomycin (85.7%) and co-trimoxazole (82.1%), but resistant to ceftazidime (100%), tetracycline (75.0%) and ciprofloxacin (71.4%). Conclusion: This study reveals high occurrence of multi-drug resistant Listeria species in faecal samples of poultry chickens in Lagos state which may be an important vector in the contamination of the environment and transmission of antibiotic resistant Listeria species to consumers.

Multiple Antimicrobial Resistance of Extended Spectrum Beta-Lactamase-Producing Escherichia coli from Small-Scaled Poultry Farms and Retail Chicken

Antibiotics used for agricultural purpose has contributed to the increased prevalence of antibiotic-resistant bacteria. The goal of this study was to investigate the prevalence and antimicrobial resistance of ESBL-producing E. coli in small-scaled poultry farms and retail chicken. The cultured E. coli isolates were subjected to phenotypic tests, susceptibility tests, and the polymerase chain reaction for detection of blacTX-M, blasHv, and blaTEM genes. From 120 samples each of chicken feces, retail chicken, soil and chicken feed, ESBL-producing E. coli isolates were detected in 75.9%, 63.6%, 39.2%, and 13.3% of the samples, respectively. Minimum inhibitory concentration （MICs） values indicated that ESBL-producing E. coli were resistance to ampicillin （MIC 〉 32 μg/mL）, gentamicin （M1C ≥ 16 μg/mL）, cefotaxime （MIC 〉 4 μg/mL） and cefhiaxone （MIC 〉 4 gg/mL）, respectively. The total resistance for imipenem was also observed at 1.0% （MIC ≥ 4 gg/mL） and none of the isolates were resistant to ceftazidime （MIC 〉 16 μg/mL）. ESBL-producing E. coli from chicken feces and retail chicken carried blasHv gene at a rate of 6.8% and 5.7%, respectively and blaCTX-M gene was also revealed at 2.9% in retail chicken. Moreover, ESBL-producing E. coli isolated from soil harbored blasnv and blaCTX-M genes at 5%. None of the feed samples yielded ESBLs genes. Twenty three resistance patterns were observed for multi-resistant ESBL-producing E. coli. This study highlights the prevalence of multi-antimicrobial resistant ESBL-producing E. coli in small-scaledpoultry farms and retail chicken, hence the need to review poultry management practices to minimize the occurrence.

Comparative Analysis of Slaughter Performance and Meat Flavor Traits of Quality Chicken under Cage Rearing and Free-range Farming Conditions

[Objective]The paper was to compare the slaughter performance and meat flavor of quality chicken under cage rearing and free-range farming conditions.[Method]A total of 4001-day-old cocks,S07 line cultivated by Sichuan Dahen Poultry Breeding Co.,Ltd.(bred for 4 succes-sive generations),were kept in cages until the end of 5 weeks of age,which were then divided into cage rearing and free-range farming groups.All cocks were fed with the same diet,and slaughter tests and meat quality analysis were carried out at the end of 10 and 22 weeks of age,respectively.[Result]The live weight,carcass weight and abdominal fat percentage in cage rearing group were significantly higher than those in free-range farming group(P<0.01),and the percentage of half-eviscerated yield and percentage of eviscerated yield in cage rearing group were significantly higher than those in free-range farming group(P<0.05),but there were no significant differences in dressing percentage,percentage of leg muscle and per-centage of breast muscle.The intramuscular fat(IMF)content and muscle fiber density of chicken in cage rearing group were significantly higher than those in free-range farming group(P<0.01),but there was no significant difference in inosinic acid(IMP)content.The content of IMF and IMF increased with the increase of feeding age,but the deposition rate of intramuscular fat was higher than that of IMF in late feeding period.[Conclusion]The study will provide reliable guidance for production and market consumption of high quality chicken.

安徽部分地区鸡场鸡毒支原体与鸡滑液囊支原体感染与垂直传播调查

为了解安徽部分地区规模鸡场鸡毒支原体(Mycoplasma gallisepticum,MG)和鸡滑液囊支原体(Mycoplasma synoviae,MS)流行感染情况,试验采集21家鸡场鸡血液样品进行血清学调查,并对3家种鸡场的种鸡群及其后代雏鸡进行MG和MS的病原检测,分析种鸡及其后代雏鸡的感染情况。结果显示,MG和MS的鸡场血清阳性率分别为95.24%和90.48%,鸡群平均血清阳性率分别为75.08%和77.01%;商品蛋鸡和种鸡的MG和MS血清阳性率高于育雏育成鸡;鸡群日龄越大,MG和MS的血清阳性率越高,其中300日龄以上鸡群的血清阳性率均为100%。病原检测发现,种鸡场存在不同程度的MG和MS感染,其中MS感染率高于MG;种鸡感染率与其后代雏鸡的垂直感染存在显著正相关,并且在垂直感染的雏鸡关节组织检测出MS病原。结果表明,MG和MS在安徽鸡场中的感染较为严重,垂直传播是雏鸡早期感染的重要途径,并且MS在雏鸡垂直感染的早期即可侵入关节组织。

2013-2020年广西重点种鸡场禽白血病净化效果分析

按照检测-淘汰-分群-再检测-再淘汰的原则,建立“生物安全+病原监测+淘汰”模式对2013—2020年广西11家重点种鸡场的种公鸡、种母鸡、育成鸡和雏鸡采集精液、蛋清、泄殖腔拭子、胎粪等样品进行禽白血病病原检测;公鸡和母鸡同时采集血浆蛋白进行禽白血病病毒(ALV)分离。通过多方式联合净化禽白血病,ALV阳性率逐年下降,净化效果非常显著。其中公鸡精液中ALV阳性率由2013年的7.45%下降到2020年的0.14%,母鸡蛋清样本ALV阳性率由2013年12.32%下降到2020年0.23%,雏鸡胎粪ALV阳性率由2018年3.60%下降到2020年0.47%。公鸡血浆蛋白病毒检出率由2013年的3.46%下降到2020年的0.78%,母鸡血浆蛋白病毒检出率由2013年的2.22%下降到2020年的0.20%。可以看出ALV净化效果非常显著,说明所建立的禽白血病净化方法在广西行之有效。

伊犁河谷林下散养鸡疫病防控措施

林下散养蛋鸡属于绿色生态循环的养殖模式,利润空间大,但该模式是一种开放式的饲养模式,养殖管理难度大,一旦发生疫病,未以及时救治,损失严重,需要养殖人员给予高度的重视,采取科学的方法策略合理防控。结合伊犁河谷林下散养鸡现状,探讨了林下散养蛋鸡常见病的预防和治疗方法。

规模蛋鸡场环境监测数智化养殖技术方案

针对蛋鸡养殖过程中环境监测智能化程度低等问题,结合养殖经验,提供了一套规模化蛋鸡场数智环境控技术方案与运行维护方案。该方案通过安全可靠的设施设备,能够及时获取鸡舍环境参数,并在权限范围内控制执行系统完成相应的调控指令,同时具备故障自检、预警、自我保护等功能,实现节约养殖成本、提升生产效率、提高鸡蛋品质、促进增收。

Detection of Toxoplasma gondii in chicken and soil of chicken farms in Nanjing region,China

Background:Soil is increasingly recognized as an important source in the transmission of Toxoplasma gondii(T.gondii).The aim of this study was to investigate the presence of T.gondii in the soil and to grasp the relationships between the contamination of soil and chicken infections.Methods:PCR method based on T.gondii-conserved gene internal transcribed spacer 1(ITS-1)as target gene and ELISA method(sGRA8-ELISA)using the recombinant protein of shortened GRA8 gene of T.gondii as antigen were developed and applied.From April 2013 to March 2014,a total of 700 soil samples were collected at various sites located in thirty farms categorized as free range farm and scale farm in Nanjing,Jiangsu,China,in different seasons.Additionally,a total of 350 sera of chickens were collected from free range farms to determine the presence of antibodies against T.gondii using sGRA8-ELISA.Results:The serological results showed that,antibodies were found in 194 of 250(67.14%)samples from farms with T.gondii positive in soil and 41 of 100 samples from farms with T.gondii negative in soil(41.00%)(P<0.01).The PCR detection of soil samples showed that,7(2.0%)of 350 samples collected from feeding zone in free range farms were found positive of T.gondii,whereas no sample was positive in scale farms.In the seasonal detections,T.gondii was found in 6(3.33%)samples collected in autumn and 1(0.56%)collected in winter.Conclusions:The results indicated that the contamination of T.gondii in soil in the free range farms was higher than that in the scale farms and seroprevalence of T.gondii in chickens in the farm with soil contamination was higher than that with no soil contamination.The soil contamination might be an effective indicator of T.gondii infection in chickens.

What are the Determinants of Large-scale Farming in China？

The Chinese Government has increased its focus on expanding farm scale to promote agricultural development since 2010. A series of favorable polices has been adopted to support large-scale farming. Using a multivariate probit model and 2015 and 2016 rural household survey data, the present paper examines the factors that influence small farmers＂ decision to become large-scale farmers. The empirical regression results suggest that the decision to become a large-scale farmer is significantly influenced by household human capital cooperative membership, marketing channels, land-transfer contracts and government policies. However, the influence of these factors differs with respect to becoming large-scale grain and non-grain farmers. These results imply that policy tools should target these factors and the appropriate group of small-scale farmers. Generally, both central and local governments should promote large-scale farming by enhancing rural households＇ human capital improving marketing channels and providing agricultural social services, as well as encouraging returning migrant workers to engage in large-scale farming,

LARGE-SCALE FARMING BENEFITS SOIL ACIDIFICATION ALLEVIATION THROUGH IMPROVED FIELD MANAGEMENT IN BANANA PLANTATIONS

Large-scale farming by agricultural land transfers has been increasingly promoted in recent years,but the possible impacts on crop production,especially cash crops,and soil acidification remain unclear.This study obtained data for 110 banana plantations in Long’an County,China,and categorized them into small(<0.67 ha),medium(0.67−6.7 ha),and large(>6.7 ha)to determine banana cultivation,nutrient management,and soil acidification rates on farms of the three sizes.Banana yield per unit area significantly increased with increased farm size,and large farms had the highest average yield(48.9 t·ha^(−1))with the least variation.Despite a significant increase in organic fertilizer and base cation inputs,nitrogen(N)surplus did not differ significantly with increasing farm size.With large farms,actual soil acidification rate was significantly lower by 19.1 to 24.0 keq·ha^(−1)·yr^(−1);however,potential soil acidification rate increased with increased overuse of phosphorus.Overall,larger banana plantations used fewer mineral N fertilizers reducing the rate of soil acidification and increasing the H+buffering provided by organic fertilizers.It is concluded that larger farms deliver the dual benefits of higher,less variable banana yield and mitigation of soil acidification by substituting organic N for mineral N fertilizers,supporting sustainable soil management and food production.

癸甲溴铵溶液在鸡场不同应用场景的消毒效果研究

为了验证癸甲溴铵溶液在鸡场不同场景的消毒效果,依据《兽用消毒剂鉴定技术规范(试行)》(1992年版),试验考察了癸甲溴铵溶液对种蛋、鸡舍空气与鸡舍物体表面的消毒效果。结果显示:癸甲溴铵溶液与鸡蛋表面特定菌作用30 min后,对其杀菌率在99%以上,可有效杀灭鸡蛋表面特定菌;癸甲溴铵溶液对鸡舍前半部分的空气自然菌的杀菌率为90.13%~96.67%,对物体表面自然菌的杀菌率为90.16%~92.70%,可有效杀灭鸡舍自然菌。研究表明,癸甲溴铵溶液对鸡蛋表面特定菌、鸡舍空气中自然菌及鸡舍物体表面自然菌均具有较好的杀灭作用,消毒效果良好。

贵州省蛋鸡养殖机械化水平发展研究

农业机械化是农业现代化的基础工程和重要标志。本文以蛋鸡养殖为例,对养殖分环节(饲料收获、饲喂、粪污处理、环境控制、集蛋)提出了蛋鸡养殖机械化水平指标体系,给出了计算方法。以贵州省426个蛋鸡养殖场采样的数据对机械化水平进行计算,对蛋鸡养殖各环节的机械化生产短板进行剖析,提出了提升薄弱环节机械化水平的建议。

禽畜养殖粪便中多重抗生素抗性细菌研究

通过对新乡地区8家养猪场和11家养鸡场饲喂抗生素情况的调研,发现头孢氨苄、阿莫西林、卡那霉素、庆大霉素等4种抗生素是该地区被普遍使用的兽药抗生素。通过多点取样法和微生物培养技术对3家养鸡场和3家养猪场不同养殖时期的粪便进行单一抗生素和多重抗生素抗性细菌的检测,结果表明养鸡场堆置1周的粪便中抗头孢氨苄的细菌比例最高,达到65.90%,对所研究的3种和4种抗生素同时抗性的比例高达8.60%—12.51%和9.73%,明显高于饲喂中药的对照养鸡场样本检测结果(0.02%—2.73%和0.12%)。养猪场堆置1周的粪便中检测到抗头孢氨苄的细菌比例也是最高,达到49.12%上,但养猪场粪便中多重抗生素抗性细菌的比例明显低于养鸡场。同时研究发现,在两种养殖场中,幼龄期粪便中检测到的多重抗性细菌比例明显高于成熟期粪便,这可能与养殖过程中鸡、猪在幼龄期由于防病和促生长等因素而同时大剂量使用多种抗生素有关。

规模化鸡场消毒剂的筛选与消毒效果评价

为评价消毒剂对规模化鸡场的消毒效果,采用有限稀释法和菌悬混合液定量杀菌试验分别测定50g/L苯扎溴铵(A)、20mL/L戊二醛溶液(B)、100g/L聚维酮碘(C)、100g/L癸甲溴铵(D)和过硫酸氢钾复合物粉(E)5种消毒剂对大肠埃希菌最小杀菌浓度(MBC)和杀灭对数值;采用带鸡消毒试验对5种消毒剂进行现场消毒效果评价。结果显示,消毒剂E对鸡舍中分离的大肠埃希菌MBC最小,杀菌作用最强,消毒剂D次之,消毒剂C、B、A杀菌作用较弱;消毒剂E、D对大肠埃希菌的杀灭对数值均极显著高于C、B、A(P<0.01),但二者差异不显著(P>0.05);消毒剂E、D带鸡消毒后30min对空气中的细菌总数和大肠埃希菌的杀灭率分别为65.07%、88.80%和43.23%、45.03%,消毒剂E对细菌的杀灭效果显著高于消毒剂D(P<0.05);消毒剂E对3栋鸡舍设施消毒后1h,设施表面细菌总数和大肠埃希菌平均下降45.76%和78.51%;消毒剂E带鸡消毒,试验组鸡群的死亡率比对照组鸡群平均下降了2.86%(P<0.05)。综合分析表明,过硫酸氢钾复合物粉适于规模化鸡场带鸡喷雾消毒。

鸡粪水厌氧处理实验研究

本文报道的实验利用两级厌氧处理技术,为中小型养鸡场的鸡粪水处理提出了一种处理工艺与新的装置。实验在HRT3 01d,有机负荷7 85kgCOD·m-3d-1的条件下,COD去除率达到了75 77%,COD产气率0.381m3·kgCOD-1d-1,出水卫生指标符合国标要求。

疫病净化对动物后代繁育的影响研究——基于全国297个规模化养鸡场的实证分析

2012年,国务院提出了《国家中长期动物疫病防治规划(2012—2020年)》,要求对16种动物疫病逐步进行控制、净化和消除。基于此,本文利用全国297个规模养鸡场的调查数据,采用随机效应模型,分析疫病净化对养鸡场动物后代繁育的影响。结果表明,已净化养鸡场的日最高产蛋率、种蛋合格率、种蛋受精率、受精蛋孵化率分别比未净化养鸡场高1.091%、1.090%、0.892%、0.528%。相比已净化养鸡场与未净化养鸡场之间后代繁育指标的差异,净化不同病种带来的差异较小。增加疫苗投入、减少兽药使用、合理设置技术人员数量可有效提升鸡群的后代繁育能力,采用封闭式的栏舍、非笼养的饲养方式、非自繁自养的引种方式以及整批的出栏方式可在某种程度上提高养鸡场动物的后代繁育能力。全国7个区域中,华北地区养鸡场的后代繁育能力最强。建议国家加强对疫病净化的宣传,积极组织疫病净化方面的培训和交流。养鸡场在开展疫病净化的同时,重视疫苗免疫工作,尽可能减少兽药的使用,有效地聘用技术人员。

我国部分地区祖代鸡群鸡传染性贫血的血清学调查与分析

为了解祖代鸡群中鸡传染性贫血病毒(CIAV)的感染情况,研究采集18个省(市)未免疫CIAV疫苗的44个祖代种鸡场4847份血清样品,采用ELISA方法对CIAV抗体进行检测,通过比较群间、空间、阳性场的抗体滴度,解析祖代鸡群CIAV感染状况。结果显示:祖代鸡群中CIAV感染较普遍,场阳性率为97.7%,个体阳性率为66.0%;不同生产用途、来源的种鸡群均有感染,且分布范围广泛;43个抗体阳性场中,有1个种鸡场抗体滴度高且变异系数小,42个种鸡场抗体滴度低或抗体滴度较高但离散程度大,有发生垂直传播的风险。结果表明,我国祖代鸡群中CIAV抗体阳性率较高,存在向父母代场垂直传播CIAV的风险。

洛阳地区规模化鸡场隐孢子虫流行病学分析

为了掌握洛阳地区鸡隐孢子虫病的流行状况,自2011年5月至2011年7月,利用饱和蔗糖溶液漂浮法和改良抗酸染色法对伊川县、孟津县、偃师市、老城区、涧西区等5个县区6个规模化鸡场的238份粪便样品进行隐孢子虫卵囊检查。检查结果显示:洛阳地区鸡场隐孢子虫总阳性率为13%(31/238),主要集中在10～50日龄的雏鸡。发现两种不同形态的卵囊,根据卵囊形态结构、大小及寄生部位,初步鉴定一种为贝氏隐孢子虫;另一种为火鸡隐孢子虫,对人具有感染性。研究结果表明:正确处理鸡场粪便,是预防周边居民和其他动物感染隐孢子虫病的必要措施。