Student Case Presentation
Investigating the Impact of Propylene Glycol Administration on Hyperketonemia, Considering Metabolite Concentrations
| Date/Time: |
9/12/2024 2:30 pm
|
| Presenter: |
Alyssa Gathje |
| Veterinary School: |
MN |
Abstract:
The study aimed to evaluate the effects of oral propylene glycol (PG) administration to lactating cows that tested positive for hyperketonemia (HYK) within the first 9 days in milk (DIM), considering liver health index (LHI) and non-esterified fatty acid (NEFA) levels at the time of HYK diagnosis. The study was performed on a commercial dairy farm in central Minnesota between May-October 2023. Multiparous cows diagnosed with HYK at 3±1 or 7±1 DIM (beta-hydroxybutyrate >1.2) were randomly assigned to a treatment (PG; 300g of PG daily for 3 consecutive days; n = 90) or control group (NoPG; no PG administered; n = 82). Non-esterified fatty acids and LHI - calculated based on blood albumin, cholesterol, and bilirubin concentrations - served as a proxy for successful transition into lactation. For statistical analysis, NEFA and LHI were dichotomized as low or high based on set thresholds (NEFA: 0.7 mmol/L; LHI: 0.08). The outcome of interest was milk yield in the first 12 weeks in lactation. Linear mixed effects models were used in all analyses and included treatment, NEFA or LHI, treatment-by-metabolite interaction, relevant covariates, and the repeated measure of week. While non-significant (P > 0.05), PG cows produced less than NoPG cows in both models. NEFA status significantly affected milk yield, with high NEFA cows producing 15.4 lb/d less (95%CI: -27.6, -3.2; P = 0.01) than low NEFA cows. Only PG high NEFA and NoPG low NEFA differed significantly (-21.6 lb/d; 95%CI: -42.9, -0.3; P < 0.05). PG and NoPG cows with high LHI had similar milk production (95.6 vs 96.2 lb/d, respectively), with greater disparities between PG and NoPG with low LHI (81.2 lb/d vs 91.6 lb/d, respectively). Surprisingly, PG administration resulted in lower milk yields. LHI and NEFA numerically impacted the effect of PG on milk production in early lactation.
