| Having broad and stable presence characteristics aflatoxin is highly toxic mycotoxins,which can cause contamination of feeds and seriously influenced on the health of animal health,food,feed industry and agriculture.The research finds that lactic acid bacteria for aflatoxin has certain antagonism,which can influence aflatoxin metabolism and reduce toxin;organic selenium can effectively inhibit the mutagenicity of aflatoxin and reduce the cancer risk,Se-enriched lactobacillus is a kind of new organic selenium preparation,playing a dual role of lactic acid bacteria and organic selenium.Therefore,Se-enriched lactobacillus,in theory,can effectively reduce the damage of body caused by aflatoxin.The experiment mainly study the toxic effects of anti aflatoxin Se-enriched Lactobacillus in vitro and in vivo in broilers.The main contents are as followings:Test one: research on lactic acid bacteria in vitro against AFB1 toxicity of selenium.1.This paper studied the influence of se-enriched lactobacillus in different concentration on growth of aspergillus flavus,germination of colony and output of toxin.The results show that the increasing of the content of selenium in se-enriched lactobacillus make inhibition rate of lactobacillus,aspergillus niger and AFB1 production increase and time is the promotion and the inhibition reached the maximum,when selenium concentration reachs 25μg/m L.2.Effect of active components of Se enriched Lactobacillus on LDH activity of antioxidant enzymes,CYP450 and adding the AFB1 in cultured chicken liver cell culture medium.In situ two-step irrigation flow method of broiler hepatocyte separation preparation,it is added to the selenium content of 0.5μmol/L,1.5μmol/L and 5μmol/L selenium(Se content)bacterial liquid and continuous culture is at 12 h after adding AFB1 and AFB1 concentration reached 50 μg/L,the determination of the supernatant after determination of the content of LDH,liver cell lysis solution of CYP450 activity determination,antioxidant index.The final results show that the different doses of Se-enriched lactobacillus can be increased significantly induced by AFB1CYP450 activity decreased and gradually increased with increase of the dose Se-enriched lactobacillus,the activity of CYP450;dose of Lactobacillus Rich in selenium can significantly reduce when the AFB1 induced LDH activity increased.Different doses of Se-enriched lactobacillus can significantly improve when the AFB1 induced GSH-Px and T-AOC activity decreased.Different doses of Se-enriched lactobacillus could significantly reduce when the AFB1 was induced by MDA content increased.Test two: the chromatographic detection of aflatoxin in method of high performance liquid chromatography was established by adopting high performance liquid chromatographic method,which was developed for the determination of AFB1 content in animal liver and muscle tissue.The method has a good linear relationship in the range of 0.5～50.0μg/L,the correlation coefficient is larger than 0.999 detection limit is 0.1μg/kg,signal to noise ratio(S/N)=3:1.Under the 0.5μg/kg,1.0μg/kg and 2.0μg/kg,the average recovery rate is91.0%-107.0% and muscle tissue average recovery rate is 94.0%-105.4%,relative standard deviation(RSD)are respectively 0.8%-1.7%,1.2%-2.0%.Test three: Se-enriched Lactobacillus on broiler tissue AFB1 content,dietary supplementation of AFB1 GST,the research activity and the expression of GSTa3 m RNA GSH-Px.250 feather male broilers,randomly divided into five groups,they are blank control group(fed with basal diet),challenged group(fed with 0.1 mg/kg AFB1 basal diet),group AFB1-Se1,AFB1-Se2 group and AFB1-Se3 group(fed in the school of toxic diets in adding0.3 mg/kg,0.5 mg/kg and 1.0 mg/kg(Se content)of Lactobacillus Rich in selenium diet,the test time was 30 days.After the finishing date,the content of AFB1 in liver,muscle,serum GST,GSH-Px activity and liver GSTa3 m RNA are determined.The results show that the different doses of Se-enriched lactobacillus can significantly reduce the AFB1 induced by chicken liver,muscle tissue of AFB1 and increase the serum GST;different doses of Se-enriched lactobacillus can significantly increase AFB1 when induced Broiler Serum GSH-Px content is reduced.AFB1 guide broiler liver tissue GSTa3 m RNA was significantly elevated,different concentration of Se-enriched Lactobacillus on AFB1 induced broiler liver tissue GSTa3 m RNA increase demonstrates a decreasing trend,but there is no significant difference among them.Test four: Se-enriched lactobacillus have effect on broiler weight,ND antibody levels and the content of aflatoxin in blood and liver.In a farm of Jinghai County,we selected 1000 broilers in 1 day,randomly divided them into lactic acid bacteria group and basic diet group,which were fed a basal diet group and add 2% of Se-enriched Lactobacillus trial period for 42 days.During the experiment,the weight gain of broilers and the antibody level of Newcastle disease were recorded and the content of aflatoxin in whole blood and liver were measured after the test.The results show that selenium enriched lactic acid bacteria group broilers weight increased significantly comparing with the control group(P<0.05).14 d,28d,42 d broilers in test group of Newcastle disease antibody titers were higher than those of the control group,but they do not reach significant level.At 28 d Se-enriched Lactobacillus group broiler blood AFB1 residues was significantly higher than that of the control group(P<0.05).At 42 d Se-enriched Lactobacillus group broiler blood AFB1 residues are significantly higher than that of control group(P<0.01).At 14 d after Se-enriched lactobacillus group broiler liver tissue AFB1 residues is significantly higher than that in the control group(P<0.05),when at28 d and 42 d,Se-enriched Lactobacillus group broiler liver tissue AFB1 residues is significantly higher than that of control group(P<0.01).Conclusion: Se-enriched lactobacillus can not only effectively reduce the residues of AFB1 in all tissues of the body,but also improve the weight gain and the production function. |
