Abstract #W323

# W323
Effect of supplemental OmniGen AF and either a negative or positive DCAD prepartum on intake and blood and urine metabolites from dry off though 10 week postpartum.
J. K. Bernard*1, Z. Wu4, D. J. Hurley2, A. L. Jones3, K. P. Zanzalari4, J. D. Chapman4, D. J. McLean4, 1Animal and Dairy Science, University of Georgia, Tifton, GA, 2College of Veterinary Medicine,University of Georgia, Athens, GA,, 3College of Veterinary Medicine, University of Georgia,Tifton, GA,, 4Philbro Animal Health Corp, Quincy, IL.

Multiparous Holsteins (80) were enrolled 60 d before expected parturition through 70 DIM to evaluate the effects of feeding OmniGen AF (OG) and Animate (AN, Phibro Animal Health Corp., Quincy, IL) on DMI, blood and urine metabolites, and milk yield and composition. Cows were blocked by expected calving date and assigned randomly within block to one of 8 treatment combinations arranged as a 2 × 2 x 2 factorial to provide: 0 (OG-) or 57 g OM (OG+) beginning at dry off through parturition; 0 (POS) or 0.59 kg/d AN (NEG) beginning 28 d before predicted calving; and OG- or OG+ postpartum. Three cows were dropped from the trial due to reasons unrelated to treatments. During the far-off period, no differences were observed in DMI: 13.7 and 14.8 kg/d for OG- and OG+, respectively. Cows fed OG+ had higher (P < 0.05) BUN and urinary pH and K concentrations compared with OG-. During the close up period, cows fed NEG had lower (P < 0.05) DMI compared with POS; 13.9 and 15.7 kg/d for NEG and POS, respectively. Concentrations of K, Cl, ionized Ca, and ionized Mg were higher (P < 0.05) for NEG (4.59, 104.05, 1.28, and 0.68) compared with POS (4.46 mEq/mL, 102.06 mEq/mL, 1.26 mmol/mL, and 0.66 mmol/mL, respectively). Immediately postcalving (0 - 2 DIM), cows fed NEG had lower concentrations of globulin, and urinary pH and Na concentrations but higher Cl (P < 0.05): 2.93, 7.59, 31.51, and 55.99 compared with 3.17 g/dl, 7.95, 53.69 mEq/L, and 37.7 mEq/L for NEG and POS, respectively. Aspartate aminotransferase was greater (P < 0.05) for OG- compared with OG+: 127.16 and 106.21 U/L, respectively. No differences were observed in DMI or milk yield postpartum but cows fed OG+ had lower (P < 0.05) SCC compared with OG-. Milk fat percentage was higher for cows fed OG+ postpartum compared with those fed OG+ prepartum only. No interactions were observed among OG and AN. Carryover effects of NEG fed prepartum on blood mineral concentrations were observed 0–2 DIM. Supplemental OG did not affect postpartum milk yield but decreased SCC consistent with previous research.

Key Words: Animate, blood metabolite, DCAD