The effect of cattle manure cultivation on moisture content and survival of Escherichia coli.

A new practice whereby wet slurry is added daily to the cattle manure bedding at the barn and cultivated has been developed in Israel. The objective of the present study was to examine the effect of manure cultivation on the persistence of Escherichia coli in a model system. A cow manure-derived E. coli strain was tagged with green fluorescence protein (GFP) and antibiotic resistance markers and was used to inoculate cow manure in 10-L buckets. After 3 successive cycles of inoculation and cultivation, wet slurry was added during an additional 2 cycles. After 32 d, the cultivated and noncultivated manure contained 677 ± 14 and 505 ± 2 g·kg(-1) DM, respectively. The cultivated manure remained drier compared with the noncultivated manure after the addition of wet slurry, and its texture remained lumpy compared with the compact, cohesive, and sticky texture of the noncultivated manure. Throughout the experiment, the counts of the tagged E. coli were less (P < 0.05) and disappeared faster in the cultivated than in the noncultivated manure. These results support the hypothesis that daily cultivation of manure may result in reduced incidence of mastitis and improves the welfare and performance of dairy cows.

Antibacterial activity of lactic acid bacteria included in inoculants for silage and in silages treated with these inoculants.

AIMS: To determine antibacterial activity in lactic acid bacteria (LAB) silage inoculants and in wheat and corn silages which were treated with these inoculants. METHODS AND RESULTS: Wheat and two corn silages were prepared in 0.25 l sealed glass jars. Inoculant treatments were prepared for each type of silage with each of 10 LAB silage inoculants at inoculation rate of 10(6) CFU g(-1). Untreated silages served as controls. Antibacterial activity was determined in the inoculants and in their respective silages with Micrococcus luteus and Pseudomonas aeruginosa. Antibacterial activity was detected in nine of the 10 inoculants whereas such activity in the silages varied. Control silages did not have antibacterial activity. CONCLUSIONS: Many LAB silage inoculants have antibacterial activity and in some cases this activity is imparted on inoculated silages. SIGNIFICANCE AND IMPACT OF THE STUDY: This study was conducted as part of a broader research objective, which is to find out how LAB silage inoculants enhance ruminant performance. The results of this study indicate that LAB silage inoculants produce antibacterial activity, and therefore, have a potential to inhibit detrimental micro-organisms in the silage or in the rumen.