Animal pathology is mainly a subject that studies the occurrence and development of animal diseases and the changes in metabolism,function and morphological structure of the body during the disease process.This article takes"Animal Pathology",the core course of animal husbandry and veterinary medicine in higher vocational colleges,as an example.We ana-lyzed the integration of theory with practice,the combination of form and function,the combination of macro and micro,and the unity of whole body and part in the teaching process,laying a solid theoretical foundation for the study of veterinary clinical professional courses.In the process of course explanation,on the one hand,by constantly exploring and innovating the basic i-deological and political concepts of the course,more attention is paid to the cultivation of students'family and country feelings,guiding students to take strengthening agriculture and promoting agriculture as their own responsibility,and cultivating"lov-ing,serving,and promoting agriculture""The builders and successors of socialism.We establish the awareness and belief of writing papers on the land of the motherland,enhance students'sense of mission and responsibility to serve the modernization of agriculture and rural areas,and the overall revitalization of the countryside,and cultivate innovative talents who know and love farmers;on the other hand,through innovative teaching methods,Explore the five-stage ideological and political teaching process of"feeling-understanding-doing-thinking-exploration",reflecting the basic concept of vocational education led by teach-ers and dominated by students.This can deeply internalize the ideological and political elements into the basic literacy of students,turn the empty elements into specific connotations,and make ideological and political education achieve the effect of moistening things silently.

本试验选用7～14日龄艾维茵肉鸡共计300只进行试验,评价枯草芽孢杆菌替代抗生素的治疗效果.试验设对照组和试验组两组,在相同饲养管理条件下,对照组雏鸡饲喂抗生素硫酸阿米卡星,试验组雏鸡饲喂枯草芽孢杆菌.试验进行7天后对枯草芽孢杆菌和抗生素治疗效果作比较.结果 显示,枯草芽孢杆菌能替代抗生素治疗鸡白痢,而且对雏鸡的生长发育没有明显影响.

研究采用多重PCR方法分别对5个猪舍及其环境中分离到的120株大肠杆菌进行了5种不同毒素基因(STa、STb、LTa、Stx1和Stx2/Stx2e)的多重PCR检测,不仅调查了猪舍内环境中大肠杆菌的5种主要毒素基因的携带情况,而且还通过对舍内、舍外环境中大肠杆菌的5种主要毒素基因的比较检测分析,研究舍内大肠杆菌5种主要毒素基因向舍外环境中的传播.结果表明,猪舍环境中大肠杆菌其携带的5种毒素基因型虽然不同,但是都有一定数量的大肠杆菌携带毒素基因,而且很多是携带2种或2种以上的毒素基因.这些致病性大肠杆菌可以通过舍内外气体的交换而传播到舍外环境.

Escherichia coli is a common bacterium in the air; it can affect the health of humans and animals. The carrying status of five primary virulence factor genes in E. coli (i.e., STa, STb, LTa, stx1, and stx2/stx2e) in various animal houses and their spread to the outside environment were investigated by comparing the air inside animal houses with that outside the houses. Multiplex polymerase chain reaction detection of the five genes was performed on samples from five chicken houses, and 117 E. coli isolates were obtained. From five swine houses, 120 were obtained, and from six cow houses, 143 were obtained. Results reveal that E. coli virulence genes derived from animal houses can be propagated via gas exchange from the inside to the outside and, depending on weather conditions, across some distance, resulting in biological pollution and the spread of pathogenic microorganisms. This study of the transmission of environmental microbial aerosols in animal houses has great significance in public health and epidemiology.

The concentration of airborne aerobic bacteria,airborne aerobic gram-negative bacteria and the species composition of the airborne gram-negative bacterial flora in 3 rabbitries were measured using 5% buck blood-blood agar and MacConkey agar No. 3(Oxoid)with Andersen-6 sampler. The results showed that the number of total airborne aerobic bacteria was between 780 to 20100 CFU/m3,the number of airborne aerobic gram-negative bacteria between 39 to 1030 CFU/m3,the species composition of the airborne gram-negative bacterial flora includedEnterobacteriaceae,Neisseriaceae,PasteurellaceaeandPseudomonadaceae. Most of gram-negativeEnterobacteriaceaeisolated wasE.coli. Besides,in two rabbit houses,Pasteurellamultocida,the most common respiratory pathogen of rabbits,was isolated.

Air samples indoor and outdoor of 6 cow houses were collected using six-stage Andersen microbial sampler for detecting the concentrations of microbiological aerosol and their distribution in each stage of Andersen sampler,and the possibly damage to animal and farm workers.The results showed that the concentrations of microbiological aerosol in cow houses were more higher,and the aerodynamic diameters of most particulate matter(PM)were very small(<2.5 μm).So,these PM could penetrate into the lower respiratory tract easily.The highest concentration of airborne aerobic bacteria was 4.19 × 105CFU/m3in cow house D;the lowest was 8.90 × 104CFU/m3in cow house E.In addition,there was no significant difference(P>0.05)in the airborne aerobic bacteria concentrations among the 6 cow houses.But,the concentrations of respirable airborne aerobic bacteria in cow house D and E were significantly higher than those of other cow houses(P<0.05).

动物舍环境中微生物气溶胶的污染是衡量动物舍空气环境卫生质量的重要指标之一。本实验的目的是通过检测猪舍环境中气载肠球菌和气载需氧菌含量的方法来衡量猪舍环境的卫生质量。通过对5个猪舍中气载肠球菌和气载需氧菌含量的测定,结果表明:5个猪舍中气载气载肠球菌和气载需氧菌的含量都较高,很可能对猪群及饲养人员构成潜在威胁,饲养环境的卫生质量有待进一步提高。

In order to observe and assess the formation and spread of Antibiotic-resistant bacteria aerosol,indoor and outside air(downwind 800 m away)samples were collected using six-stage Andersen microbial sampler,and meanwhile chicken fecal samples were also collected.The E.coli isolated from the samples were conducted on the antibiotics sensitivity testing.The results showed that E.coli isolated from various locations were completely resistant to Rifampicin and Penicillin,while they were sensitive to TOB and GEN.A different number of strains had different degrees of resistance against Norfloxacin,Streptomycin,Cefoperazone,Chloramphenicol,Sulfonamides and Tetracycline.By using Multiplex PCR,5 toxin genes:STa,STb,LTa,Stx1 and Stx2/Stx2e of 480 E.coli strains were detected,which were isolated from chicken,pig and cow houses(total 21)and its environment respectively.The results showed that all isolates carried a certain amount of toxin genes,many carrying 2 or more than 2.Altogether 426 strains of Enterococci isolated from indoor,outdoor air and fecal samples of 11 animals stables(chicken,pig,cattle,rabbit)were conducted on the antibiotics sensitivity testing.The results showed that 14.55% bacteria resistant against β-lactam antibiotics;the isolates have varying degrees of resistance to Tetracyclines;31 strains of Enterococci carried vanA and vanB resistance gene;and the majority of Enterococci carried one or several of Aminoglycoside modifying enzymes(AME)genes.

Evidence is mounting that microorganisms originating from livestock impact the air quality of the animal houses themselves and the public in the surrounding neighborhoods. The aim of this study was to develop efficient bacterial source tracking capabilities to identify sources of Escherichia coli aerosol pollution caused by pigs. Airborne E. coli were isolated from indoor air, upwind air (10 and 50 m away) and downwind air samples (10, 50, 100, 200 and 400 m away) for five swine houses using six-stage Andersen microbial samplers and Reuter-Centrifugal samplers (RCS). E. coli strains from pig fecal samples were also collected simultaneously. The enterobacterial repetitive intergenic consensus polymerize chain reaction (ERIC-PCR) and the repetitive extragenic palindromic (REP-PCR) approaches were used to study the genetic variability and to determine the strain relationships among E. coli isolated from different sites in each swine house. Results showed that 35.1% (20/57) of the bacterial DNA fingerprints from the fecal isolates matched with the corresponding strains isolated from indoor and downwind air samples (similarity ⩾90%). E. coli strains from the indoor and downwind air samples were closely related to the E. coli strains isolated from feces, while those isolated from upwind air samples (swine house C) had low similarity (61–69%). Our results suggest that some strains isolated from downwind and indoor air originated in the swine feces. Effective hygienic measures should be taken in animal farms to prevent or minimize the downwind spread of microorganism aerosol.

To study the isolation rate and toxin type of Clostridium perfringens from freshwarter fishes, 420 fresh intestinal content samples (not including intestinal tissues) of freshwater fishes (Hypophthalmichthys molitrix, Cyprinus carpio, Carassius auratus, Monopterus albus and Silurus asotus) caught from the same water reservoir were examined by bacteriological method for the occurrence of C. perfringens. Genes encoding alpha, beta, epsilon, iota, beta2 and enterotoxin from the isolates were examined by PCR for toxin type classification. These amplified toxin gene fragment were cloned and sequenced and compared with the corresponding genes in GenBank to reveal the homology. Then, alpha toxin gene detected from fish muscle (C. perfringens positive in intestinal content) was performed for food safety assessing. Results showed that C. perfringens could be isolated in 75 intestinal content samples (17.9%) from freshwater fish, 59 strains were toxin type C (alpha and beta toxin positive), 12 strains were toxin type A (alpha toxin positive) and 4 strains were toxin type B (alpha,beta and epsilon toxin positive). In addition, the gene encoding for beta2 and enterotoxin were found in type C and type A isolates, beta2 toxin was also detected from type B strains. But, toxin gene was negative in fish muscle. The homology between the detecting toxin genes and the corresponding reference exceeded 98%. This is the first report of C. perfringens alpha, beta, epsilon and beta2 toxins in freshwater fish, and beta and epsilon toxins in fish, and is the first discovery that the β2 toxin could be detected in strains of type B.

Concentration of airborne aerobic bacteria and airborne staphylococcus were measured by Andersen-6 stage sampler with the blood-glucose-agar culture medium in twelve stables of two different pig fields in Tai'an to externally evaluate the pollution and harm of airborne aerobic bacteria and airborne staphylococcus,and the component of staphylococcus were analyzed too.The result showed that the total number of airborne aerobic bacterial were 2.87×104 and 12.65×104CFU/m3,and airborne staphylococcus were 1.94×104 and 5.74×104CFU/m3 respectively in two pig fields.The component of airborne staphylococcus were staphylococcus aureus,staphylococcus epidermidis,staphylococcus saprophyicus,staphylococcus hyicus,staphylococcus xylosus,staphylococcus capitis,staphylococcus cohnii and staphylococcus equorum.Among them,the content of staphylococcus aureus was about 24 % and 27 % of the total number of staphylococcus,staphylococcus epidermidis and staphylococcus saprophyicus were the next in order.In addition,based on the distributing in the six layers of Andersen-6 stage sampler,airborne aerobic bacterial and airborne staphylococcus aureus distributed at B to E stage with aerodynamic diameters ranged from 2 to 6 μm,which could reach trachea and bronchia even bronchiole,make severe threatening for stockmen and animals respiratory tract.

The study was to evaluate inactivation of indicative bacteria or bacterial flora:Fecal Coliforms,C.perfringens(Clostridium perfringens),the total number of anaerobic and aerobic bacteria,by bioaugmenting anaerobic digestion of cow dung slurry with a commercial product containing selected strains of bacteria from genera Lactobacillus,Pseudomonas,Microzymes and Actinomycetes,along with ancillary organic compounds containing various micronutrients.Specifically,the effects of the bioaugment on the concentration of volatile fatty acids,NH4+-N,the value of pH,the number of Fecal Coliforms and C.perfringens during anaerobic digestion of dairy cattle dung slurry were studied.The results indicated that the bioaugmenting anaerobic digestion could reduce the number of Fecal Coliforms significantly(P0.05),as well as could be of advantage to form a better and more stable digestive system,however,no obvious effect on reduction of the number of C.perfringens,the total number of anaerobic and aerobic bacteria were observed.The bioaugmenting anaerobic digestion could not significantly affect the output of volatile fatty acids(VFA),NH4+-N and the value of pH(P0.05).In brief,the bioaugmenting anaerobic digestion could improve anaerobic digestive microecology and could be used for treatment of dairy cattle dung slurry before their land application.

In order to study the transmission of E.coli from chicken houses to their ambient air,the air samples,including indoor air,upwind air and downwind air of 5 chicken houses were collected using ANDERSEN-6 stages sampler and RCS.Chicken feces samples were collected according to the standard method.E.coli strains were isolated from these samples.The enterobacterial repetitive intergenic consensus(ERIC)-PCR method was applied to generate genomic amplification products of isolated E.coli.According to the concentration and genetic similarity of E.coli in every sampling site,the transmission of bioaerosol from animal houses to their ambient can be identified. The results showed that the culturable E.coli concentration in indoor air in 5 chicken houses were higher than that in upwind and downwind(P0.05 or P0.01),but there were no significant differences in E.coli concentration among different downwind site(P0.05).The fingerprints and the phylogenetic tree indicated that a part of the E.coli(34.1%) isolated from indoor air had the same ERIC-PCR fingerprints with those isolated from feces,the most of E.coli(54.5%) isolated from downwind 10 m,50 m,100 m even 200 m away from the houses had the same ERIC-PCR fingerprints with those isolated from indoor air or feces.But E.coli isolated from upwind air had the low similarity coefficients(73%-92%) with those isolated from indoor air or feces.So, it was concluded that the E.coli in chicken feces can be aerosolized and transmitted into the indoor and outdoor air,especially the downwind air.This study revealed the transmitting rule of airborne E.coli bioaerosol.Hygienic measures took in animal farms have the significance of public hygiene and epidemiology.

为了研究鸡舍环境中大肠杆菌气溶胶向舍外环境的传播,本实验采用Andersen-6级空气微生物样品收集器和RCS(reuter centrifugal sampler)-离心式采样器分别在5个鸡场舍内空气、舍外上风向10,50m和下风向10,50,100,200,400m不同距离收集气载大肠杆菌,计算每一个采样点的大肠杆菌的浓度(CFU-m3空气);并采集鸡的粪便,分离大肠杆菌.利用肠杆菌基因间重复一致序列的聚合酶链式反应(enterobacterial repetitive intergenic consensus-polymerase chain reaction,ERIC-PCR)鉴定技术,扩增不同测量点收集的大肠杆菌的DNA条带,形成聚类图谱.通过每一个采样点分离的大肠杆菌遗传相似性分析以及大肠杆菌浓度变化,确认动物舍微生物气溶胶向舍外环境的传播模式.结果显示,5个鸡场舍内空气中大肠杆菌的浓度(中间值)为9～63 CFU·m3,远远高于舍外上风和舍外下风处的大肠杆菌浓度(P<0.05),但是舍外下风不同距离间的大肠杆菌浓度差异并不显著(P>0.05).ERIC-PCR结果表明,从鸡的粪便中分离到的大肠杆菌与从舍内空气中分离到的部分大肠杆菌(34.1%)相似性可达100%,从鸡场舍外下风方向(10,50,100,200 m)分离到的多数大肠杆菌(54.5%)与舍内空气或粪便中分离的大肠杆菌相似性可达100%.而从鸡舍上风分离到的大肠杆菌与舍内空气或粪便中分离的大肠杆菌相似性仅在73%～92%之间.结果表明:从上风分离到的多数大肠杆菌并非来源于鸡的粪便或者舍内空气,而很多从舍内空气和舍外下风方向分离到的大肠杆菌来源于鸡的粪便,说明源于鸡舍的微生物气溶胶能够通过舍内外气体交换传播到舍外,依气象条件传播到舍外不同的距离,造成周边环境的生物污染以及病原微生物的扩散.对动物舍环境微生物气溶胶的发生与传播规律的研究,具有公共卫生及流行病学意义.

An AOZ method, based on high-performance liquid chromatography (HPLC), was optimized on HPLC condition such as mobile phase and wavelength to simultaneously quantify six kinds of mycotoxins [four aflatoxins (AFs), ochratoxin A (OTA) and zearalenone (ZEA)]. Conditions for immunoaffinity clean-up, HPLC and photo-derivatization were optimized in this study and successfully applied in assessment of airborne mycotoxins from a poultry house in Dalian, China. Fifty-two air samples were collected with AGI-30 air samplers using pure water as collection media. Twenty air samples (20/52, 38.46%) were positive for four toxins. Among the positive samples, airborne mycotoxin concentrations (mean±S.D.) for AFG2, AFB1, and ZEA were 0.189±0.024 (n=9), 0.080±0.003 (n=11) and 2.363±0.030 (n=5)ng/m3 air, while the concentration for OTA was 8.530 (n=1)ng/m3. No positive sample was found for either AFG1 or AFB2. A chicken may inhale 0.019–0.057ng AFG2, 0.013–0.019ng AFB1, 0.436–0.513ng ZEA, and 1.706ng OTA, respectively, in a day. A poultry worker may inhale 0.504–1.512ng AFB1, 0.752–2.28ng AFG2, 68.240ng OTA, and 17.432–20.512ng ZEA in a working day. This is the first report on airborne mycotoxins in poultry house. These data may have importance in animal and public health implications.

In order to study E. coli aerosol spreading from chicken houses to their surrounding air, air samples, including indoor and outdoor air (upwind 10 and 50 m as well as downwind 10, 50, 100, 200 and 400 m away) of 5 chicken houses were collected using six-stage Andersen microbial samplers and Reuter-Centrifugal samplers (RCS). E. coli concentrations (CFU/m3 air) collected from different sampling sites were calculated. E. coli strains from chicken feces samples were also isolated. Furthermore, the enterobacterial repetitive intergenic consensus (ERIC)-PCR method was applied to amplify the isolated E. coli strain DNA samples. Through the genetic similarity analyses of the E. coli obtained from different sampling sites, the spreading of bioaerosol from animal houses to the ambient air was characterized. The results showed that the isolated E. coli concentrations in indoor air (9–63 CFU/m3) in 5 chicken houses were higher than those in upwind and downwind air, but there were no significant differences between the indoor and downwind sites 10 m away from all the 5 houses (P>0.05). The phylogenetic tree indicated that a part of the E. coli (34.1%) isolated from indoor air had 100% similarity with those isolated from feces, and that most of E. coli isolated (54.5%) from downwind at 10, 50, 100 or even 200 m had 100% similarity with those isolated from indoor air or feces too. But those isolated from upwind air had a lower similarity (73%–92%) with corresponding strains isolated from indoor air or feces. Our results suggested that some strains isolated from downwind air and indoor air originated in the chicken feces, but most of isolates obtained from upwind air samples did not come from the chicken feces or indoor air. Effective hygienic measures should be taken in animal farms to prevent or minimize downwind spreading of microorganism aerosol.

In this study,the concentration of airborne endotoxin and airborne gram-negative bacteria were measured by the ANDERSEN six-stage sampler and AGI-30(AGI=All Glass Impinger) sampler in three different rabbit houses.At the same time,were the quantitative relationship between the concentration of airborne endotoxin and airborne gram-negative bacteria.Moreover,the sources of airborne endotoxin and airborne gram-negative bacteria were investigated by detecting rabbits' feeding stuff and feces.The result showed that the concentration of airborne indotoxin and airborne gram-negative bacteria were 22~774 EU/m~3(EU=endotoxin units) and 0.39~10.3×10~2 CFU/m~3(CFU=colony forming units) respectively.Obligate anaerobic airborne gram-negative bacteria were not detected in this experiment.Significant correlations were found between the concentration of airborne endotoxin and airborne gram-negative bacteria.However,these correlations were not very strong(r_A=0.23;r_B=0.29;r_C=0.24).So the total number of the airborne gram-negative bacteria should not be used for the estimation of the concentration of airborne endotoxin.Moreover,by analyzing the concentration of endotoxin and gram-negative bacteria in feeding stuff and feces,it is deduced that the main source of airborne endotoxin and airborne gram-negative bacteria were feeding stuff and feces.

For detection of C.perfringens toxin types four pairs of primers for alpha,beta,epsilon and jota toxin gene were succeeded in designing according to the published sequence.The multiplex PCR was applied for the i-dentification of toxin types of C.perfringens from domesticated pig,sheep and cattle faeces samples which were col-lected from earlier epidemic districts of Shandong province.The results showed that all isolated 31 samples(19.1%) were C.perfringens toxin type A,that was alpha toxin positive.This typing techniques showed that it could be used not only for identification of C.perfringens strain,but also its toxin types.The test result can guide the prevence and treatment.The detection method possesses latent application prospect.

Concentration of airborne endotoxins, airborne aerobic bacteria and airborne aerobic gram-negative bacteria were measured in 3 rabbit houses. Further, the species composition of the airborne gram-negative bacterial flora was investigated. The total amount of airborne endotoxin ranged from 22 to 774 EU/m3 (Endotoxin Units/m3). The number of total airborne aerobic bacteria varied between 780 and 20100 CFU/m3, the number of airborne aerobic gram-negative bacteria between 39 and 1030 CFU/m3. Most gram-negative bacterial isolates belonged to the family Enterobacteriaceae with E. coli as primary species. In two rabbit houses also airborne Pasteurella multocida spp. multocida, the most common respiratory pathogen of rabbits, was isolated.

For detection of C. Perfringens toxin types four pairs of primer for Alpha, Beta, Epsilon and Jota toxin gene were succeeded in designing and synthesizing according to the published sequence. The multiplex PCR was applied for the identification of toxin types of C. Perfringens from samples which were collected from earlier epidemic districts of Shandong province. The results showed that all isolated 62 samples (14. 8%) were C. Perfringens toxin type A, that was Alpha toxin positive which is different from abroad reports.