摘要:An experiment was conducted in four villges from two tehsils, namely Roorkee and Laksar of Haridwar district of Uttarakhand. Two villages from each tehsil were indentified from where minimum 10-15 farmers of different categores in each village were selected. Blood samples from cattle and buffaloes of different physiological status viz., lactating, dry, heifer, pregnant and other reproductive health were collected from jugular vein in sterilized and vacuumized test tube. During analysis the serum samples with equal volume of concentrated HNO3 were kept for overnight in a digestion tube followed by low heat (70-800C) digestion with diacid mixture. The final content was filtered through Whatman’s filter paper No. 1 (Kolmer et al., 1951). Minerals such as Ca, Mg, Zn, Fe, Cu and Mn were estimated by using AAS (Atomic Absorption Spectrophotometry). Phosphorus in blood serum (Fiske and Subbarow, 1925) using Autozyme Phosphorus kit, (ACCUREX Biomedical Pvt. Ltd.) was estimated colorimetrically. The overall blood serum mineral concentration for Ca (10.43±022 mg/dl), Mg (1.65±0.14 mg/dl), Zn (1.54±0.11 ppm), Fe (1.97±0.19 ppm) and Mn (0.54±0.02 ppm) in cattle and buffaloes of different physiological status were found above their respective critical levels whereas, Ps (3.79 ± 0.21 mg/dl) and Cu (0.46 ± 0.07 ppm) concentrations in blood serum of animals were below the respective critical levels. The average serum Ca, Mg, Zn and Fe differ significantly (P