Exogenous fibrolytic enzymes (EFE) and yeast are feed supplements that improve forage digestion in rumen, but their influences on physical reticulorumen parameters are not well studied. This study was designed to evaluate the effect of the EFE:endo-β-xylanase (37x104 U/cow/day), endocellulase (45x104 U/cow/day), endo-β-glucanase (12x104U/cow/day), and active yeast – Saccharomyces cerevisiae CNCM-1077 (10x109CFU/cow/day) supplements on reticulorumen pH (RpH) and temperature (RT) in dairy cows. Nine Lithuanian Red cows were allocated into three groups (3 cows/group): control group (C) – farm diet without supplementa- tion, enzyme group (E) – farm diet supplemented with EFE, enzyme and active yeast group (EY) – farm diet supplemented with EFE and active yeast. The feeding trial lasted for 60 d. All cows were equipped with reticuloruminal telemetric pH and temperature sensor device. Data provided by the device were used to calculate the mean RpH (RpH/24h), the mean minimal RpH ( RpH/24h min.) and mean of the time that RpH was below the threshold value of 6.0 (RpH<6.0/24h, min.). The highest RpH/24h (6.37±0.22) was observed in group EY and it was by 1.62% (p<0.05) and 1.27% (p<0.001) higher as compared with groups E and C, respectively. Also min RpH/24h (6.24±0.24) was highest in group EY and values were by 0.63% (p<0.001) and 0.65% (p<0.001) higher as compared with groups C and E, respectively.

The shortest duration of RpH<6.0/24h, was recorded in group EY, and it was by 57.76% (p<0.05) and 47.87% shorter as compared with groups C and E, respectively. In conclusion, feed supple- mentation with EFE and Saccharomyces cerevisiae CNCM-1077 had beneficial effect on RpH.

Effects of fermented extruded rye flour supplements with Lactobacillus sakei KTU05-6 or Pediococcus pentosaceus BaltBio02 on milk production and composition, as well as ruminal parameters, were determined in Lithuanian Black & White dairy cows. Also, determination of antimicrobial activities of tested lactic acid bacteria (LAB) against a variety of pathogenic and opportunistic bacterial strains previously isolated from diseased cattle was performed. The highest antimicrobial activity was demonstrated in L. sakei against S. aureus, and in P. pentosaceus against P. aeruginosa and S. aureus. The count of LAB in the supplements after 72 h of fermentation of extruded rye flour with L. sakei and P. pentosaceus was 9.6±0.4 log10 CFU/g and 9.5±0.3 log10 CFU/g, respectively. All cows (n=60) were fed the same basal diet. The treatment differences were achieved by individually incorporating (65 d.) one of the supplements: L. sakei KTU05-6 (group B; n=20) or P. pentosaceus BaltBio02 (group C; n=20). The control group A (n=20) was on the basal diet only. A supplement fermented with L. sakei does not have a significant influence on dairy cattle milk production and rumen fluid parameters. The type of LAB used has a significant influence (p<0.0001) on microbiological parameters of the rumen (TCM, TCL, TCE). The milk yield was increased (p≤0.05) using P. pentosaceus BaltBio02 supplement, and further research is needed to identify w hat is the main mechanism of the positive action.