Characterization of ketolactia in dairy cows during early lactation

Fourier transform infrared spectroscopy (FTIR) allows for the determination of milk acetone (mACE) and β-hydroxybutyrate (mBHB) concentrations, providing a potential herd monitoring tool hyperketolactia, defined as elevated ketone bodies. The study aim was to characterize mACE mBHB concentration dynamics during early lactation in Polish Holstein-Friesian cows. Milk samples (n = 3,867,390) were collected within 6 60 days (DIM) over 4-yr period (April 1, 2013 March 31, 2017) from approximately 21,300 dairy herds (average 38.7 cows/herd). Fixed effects parity, DIM, their interaction on concentrations determined using mixed model with herd-year-season fixed effect random cow effect. Published hyperketolactic (≥0.15 mmol/L) (≥0.10 threshold used classify into ketolactia groups normal (mACE <0.15 mmol/L <0.10 (HYKL; either ≥0.15 or ≥0.10 mmol/L). Additionally, HYKL categorized subpopulations having (HYKLACEBHB, mmol/L), only (HYKLBHB; (HYKLACE; Effects group subpopulation, interactions also that included subpopulation an independent variable. Across all data, influenced by well interactions. For samples, decreased increasing declining more rapidly compared mBHB. In data set, 68% 32% HYKL, respectively. Among soon after calving declined time. contrast, started lower increased reaching peak around 30 then decreased. Within 50.8, 41.3, 7.9% HYKLACEBHB, HYKLBHB, HYKLACE Between 21 11.3% classified HYKLACE. Primiparous cows had greater (14.8%) this time period. conclusion, has characterized interaction. Using published criteria interpreting it intriguing identify unique population without lactation, especially primiparous Further research is needed determine if sample represents unhealthy metabolic status adversely affects health performance.