[Objective] This study aimed to explore the presence of three causative genes Colv,Stxs and HlyE of the pathogenic E.coli from chickens,pigs and food.[Method] By using 44 E.coli strains from chickens,24 from pigs and ...[Objective] This study aimed to explore the presence of three causative genes Colv,Stxs and HlyE of the pathogenic E.coli from chickens,pigs and food.[Method] By using 44 E.coli strains from chickens,24 from pigs and 26 from food as the experimental materials,virulence genes Colv,Stxs（stx2,stx2e） and HlyE were detected with polymerase chain reaction（PCR） method.[Result] Among all the E.coli strains,the detection rate of Colv was 25% from chickens,4.2% from pigs,and 0 from food;the detection rate of Stx2（Stx2e） from all E.coli strains was 0;the detection rate of HlyE was 2.27% from chickens,0 from pigs,and 11.5% from food.[Conclusion] Virulence gene Colv shows relatively high carrying rate in E.coli from chickens and pigs;HlyE also shows a certain degree of presence in E.coli from chickens and food.展开更多
Background: The high doses of zinc oxide(Zn O) administered orally to piglets for the prevention of diarrhea and increase of growth rate can contaminate pig farms and the surrounding environment. Therefore, there is a...Background: The high doses of zinc oxide(Zn O) administered orally to piglets for the prevention of diarrhea and increase of growth rate can contaminate pig farms and the surrounding environment. Therefore, there is a need to find a replacement of high doses of dietary Zn O with an equally effective alternative. In the present study, the effect of two formulations of zinc phosphate-based nanoparticles(Zn A and Zn C NPs) on growth performance,intestinal microbiota, antioxidant status, and intestinal and liver morphology was evaluated. A total of 100 weaned piglets were randomly divided into 10 equal groups with the base diet(control) or the base diet supplemented with Zn A, Zn C, or Zn O at concentrations 500, 1000, and 2000 mg Zn per kilogram of diet. Supplements were given to animals for 10 days. Fecal samples were collected on day 0, 5, 10 and 20. At the end of the treatment(day 10),three piglets from each group were sacrificed and analyzed.Results: Comparing to that of control, the significantly higher piglet weight gain was observed in all piglet groups fed with Zn A(P < 0.05). Differences in the total aerobic bacteria and coliform counts in piglet feces after NPs supplementation compared to that of control and Zn O groups were also found(P < 0.05). The majority of aerobic culturable bacteria from the feces represented Escherichia(28.57–47.62%), Enterococcus(3.85–35.71%), and Streptococcus(3.70–42.31%) spp. A total of 542 Escherichia coli isolates were screened for the virulence genes STa,STb, Stx2, F4, and F18. The substantial occurrence of E. coli virulence factors was found on day 5, mainly in fimbrillary antigen and thermostable toxins, except for piglets fed by Zn C. Zn treatment decreased Zn blood levels in piglets fed with Zn O and Zn A(500 mg/kg) and increased in Zn C(2000 mg/kg) compared to that of control(P < 0.05). The antioxidant status of piglets was affected only by Zn A. While some changes in the liver and the intestinal morphology of piglets with NPs were observed, none were serious as r展开更多
基金Supported by Agricultural Achievement Transformation Project of the Ministry of Science and Technology(2012GB2A200045)China Postdoctoral Science Foundation(20100470565)+1 种基金Science and Technology Support Program of Hebei Province(10960408D)Science and Technology Development Project of Qinhuangdao City(201101A182)~~
文摘[Objective] This study aimed to explore the presence of three causative genes Colv,Stxs and HlyE of the pathogenic E.coli from chickens,pigs and food.[Method] By using 44 E.coli strains from chickens,24 from pigs and 26 from food as the experimental materials,virulence genes Colv,Stxs（stx2,stx2e） and HlyE were detected with polymerase chain reaction（PCR） method.[Result] Among all the E.coli strains,the detection rate of Colv was 25% from chickens,4.2% from pigs,and 0 from food;the detection rate of Stx2（Stx2e） from all E.coli strains was 0;the detection rate of HlyE was 2.27% from chickens,0 from pigs,and 11.5% from food.[Conclusion] Virulence gene Colv shows relatively high carrying rate in E.coli from chickens and pigs;HlyE also shows a certain degree of presence in E.coli from chickens and food.
基金Financial support from NAZV QK1720349 “Nanoparticles zinc as an alternative to antibiotics in pigs”ERDF “Multidisciplinary research to increase application potential of nanomaterials in agricultural practice”(No.CZ.02.1.01/0.0/0.0/16_025/0007314)+1 种基金also supported by Internal Grant Agency of Mendel University in Brno(AF-IGA2019-TP006)by CEITEC 2020 (LQ1601)。
文摘Background: The high doses of zinc oxide(Zn O) administered orally to piglets for the prevention of diarrhea and increase of growth rate can contaminate pig farms and the surrounding environment. Therefore, there is a need to find a replacement of high doses of dietary Zn O with an equally effective alternative. In the present study, the effect of two formulations of zinc phosphate-based nanoparticles(Zn A and Zn C NPs) on growth performance,intestinal microbiota, antioxidant status, and intestinal and liver morphology was evaluated. A total of 100 weaned piglets were randomly divided into 10 equal groups with the base diet(control) or the base diet supplemented with Zn A, Zn C, or Zn O at concentrations 500, 1000, and 2000 mg Zn per kilogram of diet. Supplements were given to animals for 10 days. Fecal samples were collected on day 0, 5, 10 and 20. At the end of the treatment(day 10),three piglets from each group were sacrificed and analyzed.Results: Comparing to that of control, the significantly higher piglet weight gain was observed in all piglet groups fed with Zn A(P < 0.05). Differences in the total aerobic bacteria and coliform counts in piglet feces after NPs supplementation compared to that of control and Zn O groups were also found(P < 0.05). The majority of aerobic culturable bacteria from the feces represented Escherichia(28.57–47.62%), Enterococcus(3.85–35.71%), and Streptococcus(3.70–42.31%) spp. A total of 542 Escherichia coli isolates were screened for the virulence genes STa,STb, Stx2, F4, and F18. The substantial occurrence of E. coli virulence factors was found on day 5, mainly in fimbrillary antigen and thermostable toxins, except for piglets fed by Zn C. Zn treatment decreased Zn blood levels in piglets fed with Zn O and Zn A(500 mg/kg) and increased in Zn C(2000 mg/kg) compared to that of control(P < 0.05). The antioxidant status of piglets was affected only by Zn A. While some changes in the liver and the intestinal morphology of piglets with NPs were observed, none were serious as r
