A field trial on the effect of propylene glycol on milk yield and resolution of ketosis in fresh cows diagnosed with subclinical ketosis

作者：Jessica A. A. McArt, D.V. Nydam, Paula A. Ospina, Garrett R. Oetzel · 发表于：Journal of Dairy Science · 年份：2011 · DOI：10.3168/jds.2011-4463 · 被引用次数：163 · 研究领域：Reproductive Physiology in Livestock、Genetic and phenotypic traits in livestock、Ruminant Nutrition and Digestive Physiology

The purpose of this study was to determine the effect of oral propylene glycol (PG) administration on ketosis resolution and milk yield in cows diagnosed with subclinical ketosis (SCK). Cows from 4 freestall dairy herds (2 in New York and 2 in Wisconsin) were each tested 6 times for SCK from 3 to 16 d in milk on Mondays, Wednesdays, and Fridays. Subclinical ketosis was defined as a β-hydroxybutyrate (BHBA) concentration of 1.2 to 2.9 mmol/L, [corrected] and clinical ketosis was defined as ≥ 3.0 mmol/L. [corrected]. Cows with SCK were randomized to the treatment group (oral PG) or control group (no PG); treatment cows were drenched with 300 mL of PG once daily from the day they tested 1.2 to 2.9 mmol/L [corrected] until the day they tested <1.2 mmol/L. [corrected]. Outcomes evaluated for all farms included time from SCK until BHBA test <1.2 mmol/L [corrected] or until BHBA test ≥ 3.0 mmol/L. [corrected]. Individual milk weights for the first 30 d of lactation were evaluated for the 3 farms monitoring daily milk. Semiparametric proportional hazards models were used to evaluate time to event outcomes; repeated-measures ANOVA was used to assess milk weights. A total of 741 of 1,717 (43.2%) eligible enrolled cows had at least one BHBA test of 1.2 to 2.9 mmol/L. [corrected]. Of these, 372 were assigned to the treatment group and 369 to the control group. Based on hazard ratios, PG-treated cows were 1.50 times more likely (95% confidence interval=1.26 to 1.79) to resolve their SCK a...