禁抗后仔猪细菌性腹泻的临床诊断与防治     

陈维  谭涛 《猪业科学》2021,38(8):42-45

为了促进食品安全和养猪业的健康发展，禁止在饲料中使用促生长抗生素势在必行。随着我国的饲料禁抗相关法规的推行，饲料企业被严格禁止在饲料生产过程中加入抗生素，这也导致了猪场疾病尤其是肠道疾病的高发，而仔猪肠道发育未完全，免疫系统未发育成熟，更容易发生严重的腹泻甚至死亡。文章对几种常见的仔猪细菌性腹泻疾病进行了回顾，病原包括大肠杆菌、沙门氏菌、魏氏梭菌，讨论了它们的临床症状与防控措施，为猪场在防控这些细菌性腹泻提供参考。  相似文献   

牦牛瘤胃微生物抗生素抗性基因对3种外源性刺激因子的响应     

赵佳琦  文勇立  安雅静  李子谦  齐沛森  李强  候定超 《畜牧兽医学报》2020,51(5):1126-1137

通过给牦牛投喂硫酸头孢喹肟(CEF)、盐酸二氟沙星(DIF)和黄曲霉毒素B1(AFB1),并进行瘤胃微生物宏基因组测序,旨在揭示这3种外源性刺激因子对抗生素抗性基因(ARGs)种类、抗性类型、抗性机制等的影响,对于深入研究微生物抗性组特征和抗性机制具有重要价值。选取15头牦牛,随机分5组。Cef组和Dif组分别根据说明书推荐剂量按体重计算、灌服CEF 1 mg·kg^-1和DIF 1 mL·kg^-1;E1组和E2组分别按采食量投喂AFB120、60μg·kg^-1;C组为对照组。处理7 d后,采集瘤胃液,提取DNA,Illumina HiSeq测序,对reads counts进行标准化得到TPM值,并进行方差分析。结果显示,对照组共获得132种ARGs,分属30种抗性类型,其中,四环素类tetQ和tetW基因丰度较高;Cef组tetW基因丰度增加(P<0.05),Dif组tetQ丰度增加(P<0.05);Cef组四环素类和头孢菌素类抗性基因丰度增加(P<0.05),Dif组四环素类和氨基香豆素类抗性基因丰度增加(P<0.05),E1组氨基香豆素和青霉烯类抗性基因丰度增加(P<0.05),E2组青霉烯类、头孢菌素类等9类抗性基因丰度均增多(P<0.05);Dif组Erm基因23S核糖体RNA甲基转移酶丰度增加(P<0.05),E2组中ATP结合盒超家族等3种抗性机制相关基因的丰度增加(P<0.05);3种因子均显著增加四环素类ARGs宿主的种类。结论:瘤胃是蕴含丰富ARGs的储藏库,其中,四环素类抗生素抗性基因tetQ和tetW是主要的ARGs。不仅CEF和DIF使部分ARGs的种类、抗性类型以及耐药机制相关酶等的丰度升高,增加瘤胃微生物的耐药性,而且AFB1也具有类似作用,且高剂量AFB1对抗性类型的影响范围较抗生素大。这3种因子还导致携带四环素类ARGs宿主微生物的种类数量增加,从而强化横向转移机制,加快ARGs传播,增强微生物对四环素类的耐药性。  相似文献   

食品中阪崎克罗诺杆菌的药物敏感性及分子分型研究     

张彩霞  陈颖  胡安妥  王娉  王宏勋 《中国农业科技导报》2020,22(6):123-129

克罗诺杆菌是一种革兰氏阴性菌，是配方粉中威胁婴幼儿健康的主要致病菌。近年来，乳制品及食品中常有克罗诺杆菌耐药株的报道，耐药株的出现给临床治疗带来巨大挑战。为探究PFGE型别与耐药表型之间的关联性，采用BD PhoenixTM-100全自动细菌鉴定及药敏系统对食品分离的68株阪崎克罗诺杆菌进行药敏检测，共选择19种抗生素，并采用PFGE对其进行分子分型。结果表明：4株阪崎克罗诺杆菌具有耐药性，耐药率为5.88%。其中，3株对头孢唑啉耐药，1株对四环素耐药。18株菌表现为中介，其中16株对头孢唑啉中介，2株对氯霉素中介。所有菌株对其余16种抗生素均敏感。68株阪崎克罗诺杆菌可分成58个PFGE带型，其中PT037、PT050、PT054、PT007、PT043及PT046带型分别含有4、3、3、2、2、2株菌，其余52个带型各含1株菌，带型较分散。3株头孢唑啉耐药菌株包含3个PFGE带型，18株中介菌株包含16个PFGE带型。检测的阪崎克罗诺杆菌食品分离株耐药率较低，未发现多重耐药菌株，且呈现出高度基因多态性，菌株PFGE带型与耐药性之间无明显相关性。  相似文献   

细菌生物被膜与抗生素耐药机制研究进展   总被引：7，自引：0，他引：7  

屈常林  高洪  赵宝洪  陈超 《动物医学进展》2008,29(3):86-90

细菌引发的感染已成为感染性疾病的主要原因之一,具有耐药性和难治性的特点,而且还可以对抗机体的免疫清除作用,对人类和动物的健康造成很大的危害,也给人们生活的其他方面带来了越来越严重的影响,引起了基础和临床研究的极大关注。但是细菌生物被膜对抗生素的耐药机制目前还不十分清楚,现对近年来细菌生物被膜对抗生素耐药形成的几种可能机制进行综述。  相似文献   

Salmonella enterica serovar Kentucky recovered from human clinical cases in Maryland,USA (2011–2015)     

Bradd J. Haley  Seon Woo Kim  Julie Haendiges  Eric Keller  David Torpey  Alexander Kim  Kia Crocker  Robert A. Myers  Jo Ann S. Van Kessel 《Zoonoses and public health》2019,66(4):382-392

Salmonella Kentucky is among the most frequently isolated S. enterica serovars from food animals in the United States. Recent research on isolates recovered from these animals suggests there may be geographic and host specificity signatures associated with S. Kentucky strains. However, the sources and genomic features of human clinical S. Kentucky isolated in the United States remain poorly described. To investigate the characteristics of clinical S. Kentucky and the possible sources of these infections, the genomes of all S. Kentucky isolates recovered from human clinical cases in the State of Maryland between 2011 and 2015 (n = 12) were sequenced and compared to a database of 525 previously sequenced S. Kentucky genomes representing 12 sequence types (ST) collected from multiple sources on several continents. Of the 12 human clinical S. Kentucky isolates from Maryland, nine were ST198, two were ST152, and one was ST314. Forty‐one per cent of isolates were recovered from patients reporting recent international travel and 58% of isolates encoded genomic characteristics similar to those originating outside of the United States. Of the five isolates not associated with international travel, three encoded antibiotic resistance genes conferring resistance to tetracycline or aminoglycosides, while two others only encoded the cryptic aac(6′)‐Iaa gene. Five isolates recovered from individuals with international travel histories (ST198) and two for which travel was not recorded (ST198) encoded genes conferring resistance to between 4 and 7 classes of antibiotics. Seven ST198 genomes encoded the Salmonella Genomic Island 1 and substitutions in the gyrA and parC genes known to confer resistance to ciprofloxacin. Case report data on food consumption and travel were, for the most part, consistent with the inferred S. Kentucky phylogeny. Results of this study indicate that the majority of S. Kentucky infections in Maryland are caused by ST198 which may originate outside of North America.  相似文献   

The Effects of a Natural Antibiotic Alternative and a Natural Growth Promoter Feed Additive on Broiler Performance and Carcass Quality     

《The Journal of Applied Poultry Research》2008,17(2):202-210

The use of subtherapeutic levels of antibiotics in poultry feed improves performance and morbidity in broiler chickens. However, consumer pressure related to the potential development of antibiotic-resistant bacteria has resulted in the development of nonantibiotic feed additives that may also improve broiler performance. Essential oils, organic acids, and phytogenic compounds enhance production of gastric secretions, stimulate blood circulation, and reduce levels of pathogenic bacteria. The objective of the current study was to assess the use of Biostrong 505+ and Biostrong 510 as natural growth promoters in broiler chickens. Assessment was based on the performance and carcass quality of broilers fed either a maximum-yield or a least-cost commercial broiler diet. The maximum-yield diet improved broiler performance and carcass quality. Biostrong 505+ can be used to improve feed conversion and breast yield when incorporated into diets devoid of antibiotics. This improvement in feed conversion and breast yield was accentuated when Biostrong 505+ was used in conjunction with a maximum-yield diet. Biostrong 510 improved feed conversion when used in poultry diets containing antibiotics.  相似文献   

复合乳酸菌制剂的耐受性和抑菌性研究     

辛娜  郭亮  邓露芳  郭上铭  孙林芳  张勇  王光晴 《中国饲料》2019,(9):63-67

本试验将四株饲用乳酸菌,制成复合乳酸菌制剂,通过单因素试验设计,以存活率为指标,研究复合微生态产品对高温、酸、胆盐的耐受性,采用琼脂稀释法、牛津杯法分别测定复合乳酸菌制剂对不同种类饲用抗生素的耐受性及对致病菌的抑制作用。结果表明:复合乳酸菌产品在温度65℃处理2.5、5、7.5 min以及85℃处理2.5 min对其存活率没有影响,但当85℃处理5 min,存活率下降至48%;p H为3时处理90 min存活率高达80.54%。对0.3%猪胆盐的耐受性较好,处理1 h存活率为73.52%;对抗生素(药物饲料添加剂)杆菌肽锌、亚甲基水杨酸杆菌肽耐受性最强,对吉他霉素的耐受性最差;可抑制致病菌株大肠埃希氏菌的生长。体外评价试验结果表明,复合乳酸菌制剂具有很好的益生特性,可进一步研究其在动物上的应用效果。  相似文献   

高温高湿条件下添加功能性油脂对奶牛生产性能、瘤胃发酵和生理状态的影响     

张凌洪  朱春梅  张涛 《中国饲料》2019,(14):61-65

文章旨在评估功能性油脂替代莫能菌素对高温高湿环境下奶牛生产性能、瘤胃发酵和生理状态的影响。试验选择产奶期(200±50)d,平均体重(600±75)kg的荷斯坦奶牛36头,将其随机分为3组,每组12个重复,每个重复1头牛,进行为期6周的试验(1周适应期,5周试验期),试验共设计3种日粮,对照组饲喂基础日粮,处理1组在基础日粮添加20mg/kg莫能菌素,处理2组在基础日粮添加0.05%功能性油脂。试验期间环境温度、湿度和温湿度指数分别是(25±0.55)℃、(82.0±1.20)%和74.5±0.30,表明奶牛处于高温高湿环境。结果:处理1组较对照组和处理2组显著降低了干物质和有机物的摄入量(P<0.05),较对照组显著降低了粗蛋白质摄入量(P<0.05)。试验时间显著影响有机物、蛋白质摄入量及养分表观消化率(P<0.05),同时显著影响瘤胃pH、氨氮和挥发性脂肪酸含量(P<0.05)。对照组较处理2组显著降低了血清尿素含量(P<0.05),处理和时间对血清尿素含量的影响具有显著交互效应(P<0.05)。处理1组较处理2组显著降低了脂肪产量和乳脂肪含量(P<0.05)。试验时间显著影响乳成分含量及产量(P<0.05)。结论:在本试验条件下,功能性油脂增加了乳脂产量,并且可以代替莫能菌素而不影响奶牛在高温高湿环境下的采食量、养分消化率、瘤胃发酵和生理状态。  相似文献   

Enterococcus faecium NCIMB 10415 supplementation improves the meat quality and antioxidant capacity of muscle of broilers     

Lihuai Yu  Zhong Peng  Li Dong  Hongrong Wang  Shourong Shi 《Journal of animal physiology and animal nutrition》2019,103(4):1099-1106

The present study was conducted to investigate the effects of Enterococcus faecium (E. faecium) on the meat quality and antioxidant capacity of muscle in broilers. A total of 600 Arbor Acre broiler chickens (1‐day‐old, male) were randomly divided into five treatments with six replicates (20 chickens per replicate) for each treatment. The five treatments were the control treatment (CON, basal diet), antibiotic treatment (ANT, basal diet supplemented with 0.1% chlortetracycline) and E. faecium‐supplemented treatments (LEF, MEF and HEF, basal diet supplemented with 50, 100 and 200 mg/kg of E. faecium respectively). The experiment lasted 42 days in two periods of 21 days. Results showed that there were no differences in breast meat quality among different treatments (p > 0.05). Compared with the CON and ANT treatments, the yellowness of thigh meat in E. faecium‐supplemented treatments was significantly increased (p < 0.05); the shear force of thigh meat in the LEF and MEF treatments was lower than that of the CON treatment (p < 0.05). In addition, the concentration of the inosine monophosphate (IMP) in the breast and thigh meat of the MEF treatment was significantly higher than that of the other treatments (p < 0.05). At 21 days, the total antioxidant capability (T‐AOC) level and glutathione peroxidase (GSH‐Px) activity of breast meat and superoxide dismutase (SOD) in the thigh meat of the MEF treatment were greatly increased (p < 0.05). At 42 days of age, the catalase (CAT), GSH‐Px and T‐AOC activities in the breast meat of the MEF treatment were increased (p < 0.05) and the CAT activity of thigh meat in the LEF and MEF treatments was increased (p < 0.05). In conclusion, E. faecium supplementation increased the meat quality of the thigh muscle, increased the IMP content and the activities of CAT, SOD, T‐AOC, and GSH‐Px of muscle in broilers. Supplementation with 100 mg/kg E. faecium had the greatest effects.  相似文献   

Effect of chicken egg yolk immunoglobulins on serum biochemical profiles and intestinal bacterial populations in early‐weaned piglets     

Xian Tan  Jia Li  Yali Li  Jianzhong Li  Qingping Wang  Lin Fang  Xueqin Ding  Pengfei Huang  Huansheng Yang  Yulong Yin 《Journal of animal physiology and animal nutrition》2019,103(5):1503-1511

This study was conducted to test the hypothesis that dietary supplementation with anti‐E. coli, chicken egg yolk immunoglobulins (IgY), may affect early weaned piglet (EWP) intestinal functions and enteric micro‐organisms. One hundred and forty‐eight ([Landrace × Yorkshire] × Duroc) piglets, weaned at age day 21, were randomly assigned to receive one of three diets for 14 days. Treatment group one (control group) was fed the base diet. Treatment group two (antibiotics group) was fed the base diet which was supplemented with 100 ppm colistin sulphate and 15 ppm enramycin; treatment group three (IgY group) was fed the base diet which was supplemented with 500 mg/kg anti‐E. coli IgY. The study evaluated the effects on EWPs of IgY on growth, serum biochemical, inflammatory profiles and also digestion content intestinal bacterial populations. Results showed no significant difference in diarrhoea rates between IgY‐fed EWPs and antibiotic‐treated EWPs. Serum biochemical analysis showed that EWPs fed an IgY‐containing diet had both lower (p < 0.05) cholesterol and low‐density lipoprotein compared to antibiotic‐treated EWPs. Escherichia coli populations measured in IgY‐fed EWP ileal contents, compared to the control group, were significantly reduced (p < 0.05). Enterococcus, Lactobacillus, Clostridium and Bifidobacterium populations were unaffected by the IgY treatment. Larger (p < 0.05) Enterococcus populations and lower (p < 0.05) expression levels of heat‐stable enterotoxin b (STb) were observed in IgY‐fed EWP caecal digesta compared to the control group. Enteric Lactobacillus significantly decreased (p < 0.05) in EWPs fed antibiotics while it was unaffected by IgY treatment. Dietary supplementation with anti‐E. coli IgY has the potential to suppress enteric E. coli growth, but not Lactobacillus, Clostridium and Bifidobacterium. This promotes and maintains a healthy EWP intestinal environment. These findings suggest that IgY may be used as an alternative to antibiotics in EWP diets.  相似文献