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1.
Six chicks (3–6 weeks of age) were taken randomly from each of 200 broiler farms in northern Jordan, these chicks were submitted for post-mortem and parasitological examinations. Seven Eimeria spp. were identified: E. acervulina, E. brunetti, E. maxima, E. necatrix, E. mivati, E. mitis, and E. tenella. Half (50%) of the farms surveyed had all six chicks infected, 23% of the farms were free of the infection. E. tenella was the most prevalent species (39%) followed by E. necatrix (12%), E. brunitti (12%), and E. maxima (10%). Prevalences did not vary by flock size. Also, neither the use of coccidiostat nor previous coccidiosis clinical outbreaks was associated with the prevalence of coccidiosis.  相似文献   

2.
A study was performed in 1997 to estimate the prevalence and to investigate the etiology of subclinical mastitis in Swiss dairy herds managed under guidelines of controlled organic farming. It was planned as a longitudinal study over a period of 1 year and included a stratified random sample of 152 certified organic farms and 1907 cows. Two farm visits (the first from June to October when cows were on pasture, the second from January to March when cows were confined to barns) were performed on each farm. At each visit, farm management and individual-cow data (with emphasis on milking procedures and udder sanitation) were recorded. California mastitis tests (CMTs) were performed on each udder quarter of all cows in lactation. Milk samples with CMT >1+ were submitted for somatic cell counting (SCC), bacteriological examination and to test for antibiotic susceptibility. The SCC and germ-cell counts of monthly bulk-tank milk samples were available through Dairy Inspection and Advisory Services and milk production data of 567 herd-book cows were available from breeding associations. Possible individual and environmental predictors of subclinical mastitis were identified using logistic models adjusted for clustering of the data at herd and cow levels. Data were analyzed separately for cows from 7 to 100 and from 101 to 305 days post partum. Prevalences of subclinical mastitis at the quarter level were 21.2% for lactation period 7–100 days and 34.5% for 101–305 days post partum. The geometric mean SCC in bulk-tank milk samples was 85.6×103 cells/ml. Samples at 7–100 and 101–305 days post partum were positive for Staphylococcus aureus in 16.0 and 7.4%, for coagulase-negative Staphylococci in 51.5 and 50.6%, for Streptococcus agalactiae in 0.0 and 0.8%, for other Streptococci in 19.4 and 15.6%, for E. coli in 1.0 and 0.4%, and for Corynebacterium bovis in 25.7 and 45.1%, respectively. Risks of subclinical mastitis increased significantly with increasing days post partum and advancing age of cow. Cows that were sampled when staying in alpine dairies had considerably higher risks of subclinical mastitis than cows staying in home barns. Significantly lower risks of subclinical mastitis were observed in farms where CMT was performed regularly as a control measure. Bacteria in milk from cows with mastitis exhibited antibiotic resistance at a comparable frequency as found previously in conventional farms.  相似文献   

3.
A study to estimate the prevalence of vancomycin-resistant Enterococcus faecium in faecal samples from pigs at slaughterhouses in Spain was carried out between November 1998 and January 1999 with 900 samples taken from four abattoirs representing 9.7% of all pig slaughtered in 1998. Using a selective enrichment broth with vancomycin (8 μg/ml), 64 samples (7.1%; 95% CI: 5.5, 9.0%) had E. faecium vancomycin-resistant strains that showed minimal inhibitory concentrations of 256 μg/ml (62 strains) and 512 μg/ml (two strains). Results by farm showed that 43 of the 240 pig farms represented in the sampling had at least one faecal sample with vancomycin-resistant E. faecium.  相似文献   

4.
旨在调查和分析广东省养禽场肠球菌的亚型屎肠球菌和粪肠球菌耐药性及其毒力因子流行分布特征,为控制禽源肠球菌耐药性传播、保障公共卫生安全提供理论依据。作者于2018年从广东省4个养禽场采集肠道样品493份,进行屎肠球菌和粪肠球菌的分离鉴定;采用琼脂二倍稀释法测定肠球菌的最小抑菌浓度（MIC）;PCR方法检测肠球菌的耐药基因和毒力基因。结果显示：1）共分离到125株肠球菌,其中粪肠球菌84株（鸡源66株,鸭源18株）;屎肠球菌41株,均来自鸡肠道样本。2）菌株对四环素、多西环素、红霉素几乎全部耐药,对氟苯尼考和氯霉素的耐药率高达89.60%和74.40%。屎肠球菌耐药率普遍高于粪肠球菌,而粪肠球菌对环丙沙星和利奈唑胺的耐药率高于屎肠球菌;鸭源粪肠球菌对利奈唑胺的耐药率（94%）显著高于鸡源粪肠球菌（39.4%）,屎肠球菌对利奈唑胺均敏感。从鸡分离的1株粪肠球菌对万古霉素耐药。3）耐药基因在屎肠球菌中的检出率高于粪肠球菌,鸭源分离株检出率高于鸡源。耐药基因tetL、fexA、ermB最为流行,检出率均高于90%。其次是optrA基因,检出率为73.60%,poxtA和fexB的检出率均低于20%。在3株鸭源粪肠球菌中检测出cfr基因。4）已检测的毒力基因中efaA的携带率最高,为63.04%（58/92）,其他依次为gelE（54.35%,50/92）、ace（47.83%,44/92）、asa1（44.57%,41/92）。对环丙沙星及高浓度氨基糖苷类耐药的菌株及携带cfr基因的菌株,大多携带agg、asal、gelE或ace。本研究显示养殖场禽源肠球菌耐药严重,鸭源肠球菌对利奈唑胺耐药率高,耐药基因和毒力基因流行且多样,且检测出人医临床重要抗生素耐药基因,应加强对养禽场肠球菌耐药性监测。  相似文献   

5.
Broiler chickens are often intestinal carriers of Campylobacter. During processing, Campylobacter may be spread over the carcass. Thus, undercooked chicken meat, or other foods contaminated by raw chicken can act as a source of infection to humans. This study was conducted to identify risk factors for chicken flocks being colonized with Campylobacter. Eighteen chicken farms with altogether 62 chicken compartments were studied for 1 year with visits during each growing period and sampling of chicken caecal contents at slaughter. Four to six subsequent flocks were raised in each compartment during the study. A detailed questionnaire was used to record farm parameters such as building materials, feed and water equipment, hygiene and management routines. Campylobacter prevalence varied between farms, between growing periods within the farms and also during the year, with lowest prevalence during the spring. Campylobacters were isolated from 27% out of 287 flocks. Only two farms were negative at all samplings. Often the flock following a positive flock in a compartment was negative, indicating that normal cleaning and disinfecting routines are sufficient for eliminating the bacteria from the house. Usually only one serotype was found in each positive flock. Campylobacter occurrence increased with the age of the chickens at slaughter, and also with flock size.

Univariable chi-square tests were done of the association between possible risk factors and Campylobacter prevalence. Factors associated with higher Campylobacter prevalence in flocks were lack of or diffuse hygiene barriers, increasing flock size, increasing age at slaughter, short vs. long empty periods, wet litter beds, other poultry nearby or staff handling other poultry, flocks divided before slaughter, staff loading to slaughter at several farms and occurrence of mice. Under Swedish conditions, water does not seem to be a source of infection for chickens. Origin and handling of day-old chickens, feed additives, houses and litter were not associated with higher Campylobacter prevalence.  相似文献   


6.
To determine the drug resistance of E.coli strains from swine and chicken in organic farm,collection of stool specimens was conducted in one organic farm in Conghua city,Guangdong province in 2014,in which 118 E.coli strains were separated,including 55 from chicken and 63 from swine.The sensitivity of the E.coli strains from swine and chicken to 18 kinds of drugs was detected through agar dilution method.Similar properties in drug resistance were observed both in E.coli strains from swine and chicken in the same organic farm.In consideration of the resistance rate,samples were relatively sensitive to ceftazidime,cefquinome,cefoxitin,amikacin,apramycin,gentamicin,neomycin,florfenicol,chloramphenicol,imipenem,ciprofloxacin and olaquindox (chicken 0 to 21.8%;swine 0 to 14.3%).These isolates showed moderate resistance to ampicillin and streptomycin (chicken 29.1% to 38.2%;swine 23.8% to 27.0%).About 56.4% chicken isolates and 47.6% swine isolates showed resistant to more than 3 kinds of drugs.However,severe resistance was observed in trimethoprim-sulphamethoxazole,tetracyclineand and doxycycline (chicken 45.5%,76.4% and 72.7%;swine 50.8%,81.0% and 68.3%).The results also indicated that under organic farming mode,the drug resistance rates of E.coli strains from swine and chicken were relatively low in general.Multi-drug resistance existed but was relatively slight.Although the drug resistance rate to several specific antimicrobials was high,it was still lower than that in conventional farms.Since most studies focused on the drug resistance of the bacteria under conventional farming model,this study filled the blank of the research of drug resistance under organic farming model.  相似文献   

7.
有机农场鸡、猪源大肠杆菌耐药性研究   总被引：1，自引：0，他引：1  
为了解有机养殖模式下鸡、猪源大肠杆菌的耐药情况,2014年从广东从化某有机农场鸡、猪粪便中采集并分离出118株大肠杆菌,包括55株鸡源大肠杆菌和63株猪源大肠杆菌,采用琼脂稀释法测定大肠杆菌对18种抗菌药的敏感性。结果发现,同一有机农场中,鸡源大肠杆菌与猪源大肠杆菌在耐药种类及耐药率上均呈现相似规律,对头孢他啶、头孢喹肟、头孢噻肟、头孢西丁、阿米卡星、安普霉素、庆大霉素、新霉素、氟苯尼考、氯霉素、亚胺培南、环丙沙星、喹乙醇等较敏感(鸡0~21.8%,猪0~14.3%),对氨苄西林、链霉素呈现轻度耐药(鸡29.1%~38.2%,猪23.8%~27.0%),对复方新诺明、四环素、多西环素呈现较严重耐药(鸡45.5%、76.4%和72.7%,猪50.8%、81.0%和68.3%)。鸡源大肠杆菌中3耐及3耐以上的菌株占56.4%,猪源大肠杆菌占47.6%。结果表明有机养殖模式下鸡、猪源大肠杆菌耐药率相对较低,多重耐药现象存在但相对轻微,对个别临床常用抗菌药耐药率虽较严重但比常规养殖场低。由于目前国内大部分学者致力于研究常规养殖方式下细菌耐药情况,本研究很好地填补了有机养殖模式下畜禽大肠杆菌耐药性研究的空白。  相似文献   

8.
This investigation aimed to examine coccidia infection in diary cattle in Yuzhong,Gansu province.An investigation was carried out on the Holstein calves less than one year old in six large-scale dairy farms.A total of 234 fecal samples were examined,and oocysts were identified to the species level on the basis of morphological features after positive samples were mixed thoroughly with 2.5% potassium dichromate solution.The results showed that the prevalence rate of coccidia in Holstein calves reached 46.15%.The average prevalence rate of the calves under 3 months old was 52.43%,the 4 to 6 months old calves was 37.50% and the 7 to 12 months old calves was 43.37%.Seven species of Eimeria coccidians and one species Isospora sp.including Eimeria bovis,Eimeria auburnensis,Eimeria zuernii,Eimeria alabamensis,Eimeria subspherica,Eimeria ellipsoidalli,Eimeria canadensisi,were identified in the investigation,and Eimeria bovis,Eimeria auburnensis,Eimeria zuernii were the dominant species.In conclusion,the prevalence rate of coccidiosis in dairy cattles in Yuzhong,Gansu province was high.Therefore,appropriate strategies and measures should be taken to control coccidiosis prevalence in dairy cows in this region.  相似文献   

9.
奶牛球虫病呈世界性分布,中国部分省市也有报道,但是甘肃省至今尚未有关于奶牛球虫病的相关调查。甘肃省榆中县是甘肃省奶牛主产区之一,为了解甘肃省榆中县奶牛球虫感染情况,对当地6个规模化奶牛养殖场1岁以内荷斯坦奶牛犊牛球虫感染情况进行了调查。试验采用显微镜下观察的方法检测了该地区的234份奶牛粪便样品,并对球虫阳性粪便进行重铬酸钾法孵化来鉴定球虫种类。结果发现,犊牛球虫总感染率达到46.15%,其中1~3月龄犊牛平均感染率为52.43%,4~6月龄犊牛平均感染率为37.50%,7~12月龄犊牛平均感染率为43.37%。经虫种鉴定,共发现7种艾美尔属球虫和1种等孢属球虫,7种艾美尔属球虫分别是牛艾美尔球虫(Eimeria bovis)、奥博艾美尔球虫(Eimeria auburnensis)、邱氏艾美尔球虫(Eimeria zuernii)、阿拉巴艾美尔球虫(Eimeria alabamensis)、亚球形艾美尔球虫(Eimeria subspherica)、椭圆艾美尔球虫(Eimeria ellipsoidalli)、加拿大艾美尔球虫(Eimeria canadensis),其中牛艾美尔球虫、奥博艾美尔球虫、邱氏艾美尔球虫为优势种。本次调查结果表明,甘肃省榆中县奶牛球虫感染情况严重,应引起相关部门重视。  相似文献   

10.
In order to investigate coccidium infection of a Rex rabbit farm in Fujian province, 494 fecal samples were collected from different ages of Rex rabbits and examined by McMaster's method and the method of saturated saline flotation.The results showed that the total prevalence was 87.45% and the mean oocysts per gram (OPG) value was 2.56×104.The prevalences of coccidia among each rabbit age were different, and it was highest at the age of about 40 d (98.61%) and about 65 d (98.95%) rabbits.The prevalence and OPG values at the age under 30 d (19.23% and 331) were significantly lower, and the distribution pattern of OPG values was negative binomial distribution in rabbits by using fitting of distributions.In total, 11 species of Eimeria were identified from oocyst-positive samples.The infection of Eimeria was mixed infection with more than two Eimeria species, and mostly of which were infected by 3 to 7 Eimeria species.The dominant species of Eimeria were E.perforans, E.media, E.exigua and E.magna, and their prevalences were 20.15%, 16.79%, 13.94% and 13.48%, respectively.  相似文献   

11.
为掌握福建某规模化獭兔场兔球虫病的流行情况,采用麦克马斯特计数法(McMaster's method)和饱和氯化钠溶液漂浮法,对采集的494份獭兔粪便样品中兔球虫感染情况和卵囊种类进行调查分析。结果显示,该獭兔场兔球虫总感染率和平均每克粪便卵囊数(OPG值)分别为87.45%和2.56×104,各日龄段均有感染,其中以40日龄左右兔和65日龄左右兔感染率最高,分别达98.61%和98.95%;30日龄以下哺乳仔兔感染率和OPG值均最低,分别为19.23%和331,且该场兔球虫卵囊的OPG值分布符合负二项分布。本次调查共检出11种兔艾美耳球虫,均为混合感染,感染球虫种类多为3~7种;其中感染比例最高的4种兔球虫依次为穿孔艾美耳球虫(20.15%)、中型艾美耳球虫(16.79%)、小型艾美耳球虫(13.94%)和大型艾美耳球虫(13.48%)。  相似文献   

12.
为揭示广东地区鹅场动物和环境源大肠杆菌的耐药情况及超广谱β-内酰胺酶CTX-M的流行与传播特征,本研究从广东省江门及阳江市共10处鹅场采集鹅及环境样品199份,采用MALDI-TOF-MS法分离鉴定大肠杆菌。采用琼脂稀释法对菌株进行耐药性分析,采用PCR法检测头孢噻肟耐药菌中blaCTX-M基因及其基因环境,采用脉冲场凝胶电泳（PFGE）、接合转移和质粒复制子分型等方法探究blaCTX-M基因的传播特征。结果显示,共获得196株大肠杆菌,对氨苄西林、多西环素、氟苯尼考和链霉素耐药率均超过50%,第三代头孢菌素耐药率为10%~25%,其中头孢噻肟耐药菌有49株（24.6%）。阳江地区大肠杆菌对受试药物的耐药率高于江门,且动物源高于环境源,尤其是头孢噻肟和头孢噻呋均存在显著差异（P<0.05）。头孢噻肟耐药菌中共检出19株携带blaCTX-M基因,包括blaCTX-M-55（n=17）、blaCTX-M-27（n=1）和blaCTX-M-65（n=1）,且blaCTX-M基因阳性菌均可对5~11种药物耐药,呈现多重耐药的表型。blaCTX-M-55基因环境均为ISEcp1-blaCTX-M-55-orf477,且在ISEcp1与blaCTX-M基因之间有3种长度的间隔序列;而blaCTX-M-27和blaCTX-M-65的基因环境均为ISEcp1-blaCTX-M-27/65-IS903。19株blaCTX-M基因阳性菌呈现10种PFGE谱型,存在一种主要流行的谱型（47.4%）,其包括多种来源菌株,暗示存在克隆传播现象。12株（63.2%）blaCTX-M基因阳性大肠杆菌中blaCTX-M基因转移成功,blaCTX-M基因阳性接合子携带的复制子型为IncFⅡ（n=10）和IncHⅠ2（n=2）,且存在多西环素和氟苯尼考耐药表型与blaCTX-M基因共转移现象。研究发现,阳江鹅场大肠杆菌耐药情况较为严重,blaCTX-M基因存在一定的流行性且以blaCTX-M-55亚型为主,blaCTX-M基因阳性菌的克隆传播和质粒及插入序列ISEcp1介导的水平传播是导致该基因在鹅场大肠杆菌中扩散的主要原因,应引起高度重视。  相似文献   

13.
To investigate the aerotransmission of Escherichia coli (E.coli) carrying the plasmid-mediated quinolone resistance (PMQR) genes,airborne E.coli were isolated from indoor air,upwind air and downwind air samples in five swine farms.Fecal samples from swine houses were randomly collected to isolate the E.coli.The sensitivities of the E.coli strains against 14 antibiotics were tested.The E.coli carrying the PMQR genes (qnr,aac(6')-Ib-cr,qepA) were identified by ERIC-PCR,and then the genetic fingerprints of E.coli were established to analyze its origins and spread toward the outside surroundings.The results showed that E.coli isolated from five swine farms showed high resistance against 12 antibiotics,such as gentamicin,kanamycin,tetracycline,streptomycin,nalidixic acid and sulfamethoxazole,and presented multi-drug resistant.Results of ERIC-PCR showed that 46.34% (19/41) of strains isolated from indoor air samples had the same origin with fecal-obtained strains,and 73.68% (14/19) of them shared the same PMQR genes with fecal-obtained strains.68.42% (26/38) of strains isolated from downwind air samples had the same origin with fecal-obtained or indoor air-obtained strains,and 65.38% (17/26) of them shared the same PMQR genes with fecal-obtained or indoor air-obtained strains.This indicated that E.coli carrying PMQR genes and originating from feces in swine houses could form aerosols to pollute the indoor air and then spread to the downwind air through air exchange (≥400 m),which could be a potential threaten to public environment and human health.  相似文献   

14.
为了调查养猪场携带质粒介导喹诺酮类耐药基因大肠杆菌的气源性传播情况,本试验分别在5个猪场舍内及舍外上风向和下风向不同距离收集空气样品,并在舍内随机采集粪便样品,分离大肠杆菌。药敏试验检测其对14种抗生素的耐药性。以质粒介导喹诺酮类耐药基因(qnr、aac(6')-Ib-cr、qepA)为指示基因,利用肠杆菌基因间重复一致序列聚合酶链式反应(ERIC-PCR)鉴定技术,分别对5个猪场不同样品中大肠杆菌的遗传相似性进行分析,评估其向舍外空气的传播情况。结果显示,5个猪场中的大肠杆菌对庆大霉素、卡那霉素、四环素、链霉素、萘啶酸、复方新诺明等12种常用抗生素耐药率较高,且呈现多重耐药。ERIC-PCR结果显示,46.34% (19/41)的舍内空气分离株与粪便分离株来源相同,其中73.68% (14/19)的分离株携带的耐药基因也相同;68.42% (26/38)的舍外空气分离株与舍内空气或粪便分离株来源相同,其中65.38% (17/26)的菌株携带相同的耐药基因。结果表明,起源于舍内粪便的携带质粒介导喹诺酮类耐药基因的大肠杆菌能形成气溶胶污染舍内空气,并借助舍内外气体交换,传播到舍外不同距离空气中(≥400 m),对养殖场周围的环境卫生及社区居民的健康形成威胁。  相似文献   

15.
We conducted an observational study to estimate prevalence and risk factors for Salmonella spp. and Campylobacter spp. caecal colonization in poultry. Eighty-one broiler chicken and 59 turkey flocks selected among flocks slaughtered in the province of Quebec, Canada, were included in the study. Flock status was evaluated by culturing pooled caecal contents from about 30 birds per flock. Exposure to potential risk factors was evaluated with a questionnaire. Odds ratios were computed using multivariable logistic regression.

The prevalence of Salmonella-positive flocks was 50% (95% CI: 37, 64) for chickens and 54% (95% CI: 39, 70) for turkeys, respectively. Odds of Salmonella colonization were 2.6 times greater for chicken flocks which failed to lock the chicken house permanently. In turkeys, odds of Salmonella colonization were 4.8–7.7 times greater for flocks which failed to be raised by ≤2 producers with no other visitors allowed onto the premises, or origin from a hatchery.

The prevalence of Campylobacter-positive flocks was 35% (95% CI: 22, 49) for chickens and 46% (95% CI: 30, 62) for turkeys. Odds of colonization were 4.1 times higher for chicken flocks raised on farms with professional rodent control and 5.2 times higher for flocks with manure heap >200 m from the poultry house, and also increased with the number of birds raised per year on the farm and with the age at slaughter. For turkeys, odds of Campylobacter flock colonization were 3.2 times greater in flocks having a manure heap at ≤200 m from poultry house and 4.2 times greater in flocks drinking unchlorinated water.  相似文献   


16.
A prospective cohort study was conducted in the Brittany region to identify the risk factors related to foot-pad dermatitis (considered an indicator of animal well-being) in chicken and turkey broilers reared under commercial conditions. Factors related to the shed, equipment, litter management and stocking density were recorded; the dependent variable was the prevalence of lesions observed on the slaughterhouse chain. Lesions were scored from 0 (no lesion) to 3 (severe lesion). Our survey lasted from May 1999 to October 2000. Fifty flocks of chicken broilers (15 farms), 27 flocks of female turkey broilers (21 farms) and 41 flocks of male turkey broilers (27 farms) were surveyed. In chicken broilers, 10% of flocks were of high quality (80% of birds with score 0) and this was related to the use of concrete floors with a thin layer of wood shavings. In turkey broilers, 48% of female and 46% of male flocks were of bad quality (>10% of birds with score 3). A poor fan ventilation system (<150 m3/h/kg) was a significant risk factor. Turkey flocks of high quality were not observed. Stocking density had no influence on the prevalence of foot-pad dermatitis. We concluded that it is possible under high commercial stocking densities to have flocks with a low prevalence of foot-pad dermatitis in chicken broilers, whereas it is not in turkey broilers. Hence in chicken broilers, implementing a monitoring system based on the observation of foot-pad dermatitis prevalence at slaughter appears to be more appropriate than to legislate stocking density. In turkey broilers, it would probably be necessary either to reduce the stocking density drastically or to investigate new systems of floor drainage.  相似文献   

17.
This experiment was designed to study the complex of Lactobacillus rhamnosus fermented herbal and Bacillus subtilis on White Feather broiler immunity performance and impact of Escherichia coli infection.360 one-day-old broiler chickens were randomly divided into 3 groups with 4 replicates in each group and 30 chickens per replicate.The pretrial period lasted for 7 d,and the experiment lasted for 35 d.The chickens in the group Ⅰ(positive control group) and group Ⅱ(negative control group)were all only fed a basal diet,group Ⅲ was test group,by additive 1% fermented herbal preparations,groups Ⅱ and Ⅲ were intraperitoneal injection of 1 mL E.coli at 35 d,broiler mortality,immune organ index,cecalmicroflora content,immunoglobulin levels,IL-2 and IL-6 content were tested.The results showed that injection of E.coli caused massive death of chickens,group Ⅱtook up to 75.00%,it was significantly higher than groups Ⅰ and Ⅲ (P < 0.05),the mortality in group Ⅲ was significantly lower than group Ⅱ(P < 0.05),was only 23.33%.Injection of E.coli maked spleen index and thymus index of group Ⅱincreased significantly (P < 0.05),the spleen index and thymus index of groups Ⅰ and Ⅲ were no significant difference (P > 0.05).E.coli counts was significantly decreased after injectionin group Ⅲ (P < 0.05),but the number of intestinal Lactobacilli of group Ⅲ was significantly increased (P < 0.05),and inhibited the propagation of E.coli,the counts of E.coli in groups Ⅰ and Ⅲ were no significant difference (P > 0.05).At 42 d,the sIgA of the intestinal fluid in group Ⅲ were higher than that of groups Ⅰ and Ⅱ with 11.99% and 36.56%,respectively(P < 0.05).The serum IgG concentrations of group Ⅲ was higher than that of groupsⅠand Ⅱwith 14.68% and 28.15%,respectively(P < 0.05).At 42 d,the IL-2 content of group Ⅱ was the lowest,it was significantly lower than group Ⅲ(P < 0.05),the IL-6 of group Ⅲ was significantly lower than group Ⅱ(P < 0.05).  相似文献   

18.
旨在了解奶牛养殖场环境中大肠杆菌流行情况及遗传多样性，探究不同样品分离菌株的遗传关系及系统进化分群情况，收集2017—2019年新疆某大型奶牛场养殖环境中的209份样品进行大肠杆菌分离和16S rRNA鉴定，对非重复菌株进行ERIC-PCR分型和系统进化分群试验。结果显示，共分离到338株大肠杆菌，分离率为67.46%。ERIC-PCR将其分为Ⅰ~ⅩⅣ共14型。Ⅳ（196株）型为优势型；其次为Ⅰ型（59株）、Ⅴ（31株）、Ⅹ（11株）；剩余41株分布于其他10种型。除2株未分群外，其他被分为6个群，B1群（75.45%）分布最多，其次是A群（18.34%）、C群（2.96%）、D或E群（1.18%）、F群（0.30%）。综上表明，奶牛养殖场环境中大肠杆菌存在广泛的DNA多样性，且不同时间及来源菌株间存在较近的亲缘关系；系统进化分群以B1群为主。  相似文献   

19.
Molecular cloning and characterization of chicken NK-lysin   总被引：1，自引：0，他引：1  
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20.
试验旨在研究鼠李糖乳杆菌发酵中草药复合枯草芽孢杆菌对白羽肉鸡生长后期免疫性能及大肠杆菌感染的影响。选取体重相似、健康状况基本相同的360只1日龄肉鸡随机分成3个组,每组4个重复,每个重复30只。试验预试期7 d,正试期35 d。试验Ⅰ组为阳性对照组,试验Ⅱ组为阴性对照组,均饲喂基础日粮,试验Ⅲ组在基础饲料中添加1%发酵中草药制剂,且试验Ⅱ、Ⅲ组在肉鸡35日龄时腹腔注射大肠杆菌菌悬液1 mL,连续攻毒2 d,测定肉鸡死亡率、免疫器官指数、盲肠菌群含量、免疫球蛋白水平和白介素含量。结果表明,腹腔注射大肠杆菌造成鸡大量死亡,试验Ⅱ组高达75.00%,显著高于试验Ⅰ、Ⅲ组(P < 0.05),使用发酵中草药微生态制剂后鸡死亡率显著下降(P < 0.05),仅有23.33%;注射大肠杆菌后试验Ⅲ组脾脏指数和法氏囊指数显著升高(P < 0.05),但使用发酵中草药微生态制剂后脾脏指数接近于试验Ⅰ组,而法氏囊指数稍高于试验Ⅰ组,说明发酵中草药微生态制剂可以抵抗大肠杆菌感染,脾脏和法氏囊发育不受影响;注射大肠杆菌后试验Ⅲ组大肠杆菌数量显著下降(P < 0.05),但试验Ⅲ组由于饲喂发酵中草药复合芽孢杆菌制剂,肠道乳杆菌数量显著增加,抑制大肠杆菌的繁殖,从而大肠杆菌数量与正常饲喂状态下的试验Ⅰ组趋于一致;42日龄时,盲肠内容物sIgA含量试验Ⅲ组分别高出试验Ⅰ、Ⅱ组11.99%和36.56%(P < 0.05),血清IgG含量试验Ⅲ组分别高出试验Ⅰ、Ⅱ组14.68%和28.15%(P < 0.05);42日龄时,试验Ⅱ组IL-2含量最低,显著低于试验Ⅲ组(P < 0.05),试验Ⅲ组IL-6含量显著低于试验Ⅱ组(P < 0.05)。  相似文献   

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