Comparison of Two Protocols for Propylene Glycol Administration in Periparturient Dairy Cows: Effects on Blood Metabolites, Milk Production and Reproduction

摘要

Comparison of two protocols for propylene glycol administration in periparturient dairy cows was studied in 25 cross-bred Holstein Friesian cows. All cows were drenched with 400 mL of propylene glycol for 7 days before expected calving date. After calving, 12 cows were drenched with propylene glycol for 14 days and 13 cows were drenched for 30 days. Results revealed that cows in both groups did not lose their body condition scores during the periparturient period. Average milk yields during 20 weeks of lactation did not differ between the two groups. All blood metabolites at 2 weeks prepartum and at 2 and 4 weeks postpartum did not differ between the two groups. Serum triacylglycerol and glucose concentrations were higher at 2 weeks prepartum and decreased at 2 weeks postpartum. Average days from calving to first estrus were 61±10.9 and 65.5±8.3 days for cows in 14-group and 30-group, respectively and did not differ between the two groups. Results suggested that drenching propylene glycol for either 14 or 30 days postpartum had similar effect on milk production, blood metabolites and days from calving to first estrus.