Effects of a Drinkable Drench in Primiparous Holstein Cows1

Primiparous Holstein cows (n = 30) were used in a completely randomized design with 3 drench treatments: 37.85 L of water (control), 37.85 L of water plus 355 mL of propylene glycol (PG), and 37.85 L of water plus 900 g of a commercial drinkable drench product (DDP). Both PG and DDP provided similar amounts of glucose precursors. A single drench was administered at 0900 to 1100 h within 24 h of parturition. All cows were fed the same diet from parturition until d 10. Blood was sampled at 0, 2, 4, 6, 8, and 10 h after drench administration to determine acute responses and once daily from d 1 until d 10 postpartum to determine chronic responses. Treatments did not affect DMI (18.4, 18.5, and 19.6 for the control, PG, and DDP, respectively). Treatment did not affect serum glucose concentrations during the acute response period; however, both PG and DDP tended to maintain greater serum glucose after treatment relative to the control (treatment x time, P = 0.10). Both PG and DDP significantly decreased acute serum nonesterified fatty acid (NEFA; P < 0.05) and BHBA (P < 0.01) concentrations compared with the control. Serum glucose, NEFA, and BHBA were not affected (P > 0.34) during the first 10 d after administration. Administration of DDP or PG after parturition was equally effective in decreasing serum NEFA and BHBA and increasing serum glucose concentrations within hours after drenching; however, the effects were not maintained during the first 10 d postpartum. Because of the greater incidence of metabolic disorders in multiparous cows, administration of a DDP might be expected to produce additional benefits beyond those reported here for primiparous cows.