Effect Of Lactic Acid Bacteria Inoculants On Quality And The Content Of6Mycotoxins In Fermented Total Mixed Ration

In recent years, fermented total mixed ration (FTMR) gradually get people’s attention, and have begun to use by the dairy farms. However, FTMR inevitably cause the loss of nutrients during storage, cause secondary fermentation when feeding if handled improperly, even contaminated by mold during storage. Many studies show that the addition of lactic acid bacteria has a significant effect on silage preservation and prevention of mold contamination, although FTMR shares the same principle with silage, the fermentation of material vary widely. This study aimed to explore the effect of Lactic Acid Bacteria(LAB) on the Content of FTMR nutrients during storage, digestibility in vitro and content of mycotoxins at the end, for providing a scientific reference in the use of FTMR more efficiently of the dairy farm. Tests include the following three parts:1Effect of the Lactic Acid Bacteria Inoculants on storage of FTMR The effect of three LAB inoculants on FTMR was studied in this part. Four FTMR groups(control group, BM group, CL group and YX group) with different LAB were respectely put into fermentation bags, and were stored in the room temperature condition after being vacuumed. Sensory evaluation, routine nutrients and fermentation indicators were measured at0,2,4,8,16,32,64and96days after being fermented. The results showed that:four test groups have no mildew at96days, and the three test groups could improve the sensory evaluation of the FTMR. The Dry Matter(DM), Ash, Neutral Detergent Fiber(NDF) and Acid Detergent Fiber(ADF) showed no significant difference (P>0.05), and Crude Protein(CP) showed significant difference(P<0.05) with different LAB. The pH value of four groups reduced to4.2at96days, the content NH3-N of the three test groups higher than the control group, the LAB have significantly increased the content of Lactic Acid(LA), no Acetic Acid(AA) was found in the whole process. The conclusion is that LAB could improve the fermentation effect, with economic efficiency,64days is appropriate fermentation time.2Effect of the LABI on digestibility of FTMR in vitro The effect of three LAB inoculants on FTMR digestibility in vitro was studied in this part. The fermentation of FTMR of all groups(control group, BM group, CL group and YX group) last64days, and then gas production rate, cumulative gas production were tested by Reading Pressure Technique(RTP), and the routine indicators and fermentation indicators were tested too. The results showed that:The gas production rate and the cumulative gas production in the four groups had no significant difference(P>0.05). The pH, NH3-N and Volatile Fatty Acids(VFA) in the BM group and CL group had significant difference with other groups(P <0.05). The Dry Matter Digestibility(DMD) in the BM group and YX group had significant difference with other groups(P<0.05), and the Neutral Detergent Fiber Digestibility(NDFD) in the CL group and the YX group had significant difference with other groups(P<0.05). The conclusion is that the gas production rate and the cumulative gas production of the four groups had no significant difference(P<0.05), and the routine indicators and the fermentation indicators were effected by LAB inoculants to some extent. At last, YX is the best one of three LAB inoculants.3Effect of the LABI on content of6Mycotoxins of FTMR The effect of LAB on content of6mycotoxins were studied in this part. The fermentation of FTMR of all groups(control group, BM group, CL group and YX group) last64days, the Aflatoxin(AFT) was detected by Multi-column purification-electrochemical derivatives-high-performance liquid chromatography, and Zearelenone(ZEN) and Deoxynivalenol(DON) were also detected by Immunoaffinity column-high-performance liquid chromatography, external standard. The results showed that:the content of Aflatoxin B1(AFB1) were respectely1159.95μg/kg,665.71μg/kg,964.12μg/kg and851.74μg/kg, ZEN were respectely1159.95μg/kg,665.71μg/kg,964.12μg/kg and851.74μg/kg, DON were respectely140.34μg/kg,117.46μg/kg,130.89μg/kg and130.09μg/kg, and Aflatoxin G1(AFG1), Aflatoxin B2(AFB2) and Aflatoxin G2(AFG2) were not found in all four groups. These results suggested that LAB can significantly reduce content of mycotoxins in FTMR, and the BM was the best of all.