MANISHI MUKESHBRIJESH2024-08-162024-08-162023https://krishikosh.egranth.ac.in/handle/1/5810213301The present study was conducted with an aim to generate the baseline composition, to assess the antioxidant and mineral level and metabolic signatures of colostrum, transition and mature milk of Murrah buffalo (Bubalis bubalis). The composition data of fat, Protein, Lactose and SNF was generated in 48 samples at 0- day colostrum, 2-, 4-, and 6-day transition milk and 50- and 100- day mature milk of Murrah buffalo. The fat, SNF and protein (P<0.05) level were significantly higher in colostrum as compared to other lactation days. In contrary, lactose percentage was lowest in colostrum than transition and mature milk. To determine the antioxidant activity, Colostrum, transition and mature milk samples of Murrah buffaloes representing 0-day, 2-day, 4- day, 6-day and 100-day, were processed in duplicate for various antioxidant parameters such as DPPH, FRAP, Catalase and GSH. The analysis revealed that all the antioxidants studied in the present study have significantly (P<0.05) higher values in colostrum samples as compared to transition and mature milk. The analysis of major (Na, K and Mg) and trace (Fe, Cu, Zn and Mn) mineral elements through Atomic Absorption Spectroscopy has revealed that Na is present significantly (P<0.05) in higher concentration as compared to the other mineral elements included in the present study. For the metabolomics, total of 60 milk samples collected at 0, 2-, 4-, 6-, 50 and 100-days post calving representing colostrum, early transition and mature milk of Murrah buffaloes were collected. The samples were freeze dried and subjected to 1D 1H 800 MHz NMR spectrometer equipped with a Cryoprobe (at 300 K) for the metabolic profiling of colostrum, transition and mature milk. The NMR spectra revealed a total of 26 metabolites. The metabolites such as lactose, guanidoacetate, glycerophosphocholine, glycine, betaine, choline, NAG, O-PCh, UDP-Galactose, UDP-Glucose, Myo-Inositol, UDP-NAG, creatine, carnitine, creatine phosphate, creatinine, O- acetylcarnitine, fucose, glutamate, threonine, lactate, lactulose, leucine, malonate and maltose etc. could be identified with varying concentration in colostrum, transition and mature milk. Partial least square discriminate analysis (PLS-DA) showed distinct grouping of colostrum, transition and mature milk samples. The ranking of metabolites responsible for distinct separation of three sample types (colostrum, transition and mature milk) from each other was done based on variable importance in projection (VIP) score. The hierarchal clustering demonstrates that the metabolome signature of colostrum samples (0 day) is distinctly different from that of the rest of the samples. The analysis revealed that branched chain amino acids leucine, isoleucine, and valine were significantly (P<0.05) high in colostrum samples. Additionally, metabolic pathway analysis showed that the different metabolites were enriched underamino acid metabolism, citrate cycle (TCA cycle), aminoacyl-tRNA biosynthesis, valine, leucine and isoleucine biosynthesis. In summary, our study could successfully utilize NMR technique to establish the metabolome signature of colostrum and milk samples of Murrah buffaloes. Further, the study highlighted the higher abundance of metabolites in colostrum vis a vis mature milk sample. Such information could provide tangible information on type of metabolites available in colostrum and mature milk of Murrah buffaloes for further commercial application.EnglishThesis