Use of extruded rye wholemeal for selected lactobacilli multiplication and its influence on dairy cows rumen fluid parameters, milk yield and composition
The use of live bacterial cultures in the animal industry, whether to improve resistance to specific pathogens or to non-specifically enhance animal health, improves production parameters (Kenny et al., 2011). Different lactic acid bacteria (LAB) strains belonging to similar species have different properties and so effects/benefits can be different from one strain to another within the same species (Fukushima et al., 2011). The aim of this study was to investigate the influence of Lactobacillus sakei multiplied in extruded rye substrate on dairy cows rumen fluid parameters, milk yield and milk composition. Extruded rye wholemeal (moisture content 8.6%) produced by a single-screw extruder (Ustukiu malunas Ltd, Lithuania) was used as the fermentation medium for LAB multiplication. The fermented extruded rye (65% moisture content) has been prepared by using 30 kg of extruded rye whole meal fluor and 45 L of water. LAB cell suspension (600 mL) containing about 1011cfu/mL was added, followed by fermentation for 24 h at 30ŗC temperature. The final cfu/g in the fermented product was on average 109 cfu/g. The experiment was performed in the winter at the farm of Black & White Holstein dairy cattle. Trial and control groups received identical diets, however the trial group received also 100 g of fermented rye flour (containing 109 cfu/g of LAB) per head of the supplement (daily, during 65 days). Results showed, that ruminant pH, total and individual FFA, total N and NH₃-N, D(-) lactate, reduction activity of bacteria, glucose fermentation reaction, protozoa number, TLC and TCE in trial group had no significant difference (P>0.05) from those characteristics in control group and in trial group at the beginning of the experiment, but L(+) lactate and TCM were different. At the end of the experiment L(+) lactate in trial group decreased by 0.28 mmol/L (P0.05)
