The effectiveness of fibrolytic enzymes and active yeast on improving reticulorumen pH in dairy cows

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 supplementation, 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 (minRpH/24h) 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 minRpH/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 supplementation with EFE and Saccharomyces cerevisiae CNCM-1077 had beneficial effect on RpH.

Changes in saliva proteins in cows with mastitis: A proteomic approach

This study aimed to evaluate the possible saliva proteome changes in cows with mastitis using a Tandem Mass Tags (TMT) proteomics approach. For this purpose, the salivary proteomes from healthy cows and cows with mastitis were analysed, and their serum proteomes were also studied for comparative purposes. A total of eight saliva and serum paired samples for each group were used for the proteomic study, and eight additional samples for each group were analysed in the analytical and overlap performance studies. In saliva samples, 2192 proteins were identified, being sixty-three differentially modulated in mastitis. In serum, 1299 proteins were identified, being twenty-nine differentially modulated in mastitis. Gamma glutamyl transferase (γGT) in saliva and serum amyloid A (SAA) were validated by commercially available automated assays. In conclusion, there are changes in protein expression and metabolic pathways in saliva and serum proteomes of cows with mastitis, showing different response patterns but complementary information.

Concentration of lactoferrin and immunoglobulin G in cows’ milk in relation to health status of the udder, lactation and season

The aim of this study was to analyze an effect of udder health status, somatic cell count (SCC), stage and number of lactations, and different seasons on the concentration of lactoferrin (LF) and immunoglobulin G (IgG) in quarter milk samples (n=120) from crossbreed (Lithuanian Black-and-White & Holstein) dairy cows. Quarter health status was based on SCC and microbiological analysis. The highest mean value of LF and IgG were observed in quarters with subclinical mastitis 0.1 ± 0.02 mg/ml and 0.41 ± 0.06 mg/ml, respectively. Grouping the data according to SCC revealed increased LF (0.07 ± 0.01 mg/ml as against 0.06 ± 0.01 mg/ml) and IgG values (0.27 ± 0.05 mg/ml as against 0.23 ± 0.02 mg/ml) in DQ (SCC from 201,000 ≥ 401,000 cells/ml) compared to HQ (SCC up to 200,000 cells/ml). The milk LF and IgG levels were effected by stage of lactation (p<0.01 and p<0.05, respectively) and season of the year (p<0.001 and p<0.001, respectively). Nevertheless, SCC and subsequent lactation (p>0.05) had no effect on these immunity components.