Metabolic parameters and their relationship to energy balance in multiparous Simmental, Brown Swiss and Holstein cows in the periparturient period as influenced by energy supply pre- and post-calving.

Summary A study was conducted to evaluate the effects of three energy supply (E) levels [low (L), medium (M), high (H)], both pre-partum (PRE) and post-partum (POST), and their interactions on metabolic parameters and energy balance (EB) in dairy cows of three breeds. In both phases, E levels applied to a total of 81 multiparous cows of breeds Simmental (SI), Brown Swiss (BS) and Holstein–Friesian (HF; n = 27 for each breed) were 75%, 100% and 125% of recommendations of the German Society of Nutrition Physiology, using a 3 × 3 factorial arrangement of treatments. During the pre-calving period, serum concentrations of non-esterified fatty acids (NEFA) were higher for LPRE cows, and glucose concentrations were elevated for HPRE cows. During the lactation period, NEFA concentrations were greatest for treatment LPOST. Mean concentrations of β-hydroxybutyrate (BHB) were highest for cows of the LPOST treatment, intermediate for MPOST and lowest for HPOST. Glucose concentrations were lower for LPOST cows. SI cows had lower BHB concentrations both pre- and post-calving and higher glucose concentrations during early lactation than the other breeds. BHB concentration POST was highest for BS cows. Restricted feeding PRE resulted in a better energy status of cows fed above energy requirements POST (EPRE × EPOST interaction). HF cows had a higher EB pre-calving, whereas SI cows had a less negative EB during early lactation, compared with the other breeds respectively. Correlations of serum NEFA, BHB and glucose concentrations with EB were strongest during the transition period. Results suggest that controlling energy intake during the dry period might be advantageous for the energy status of dairy cows after calving, whereas energy restriction in early lactation leads to metabolic stress. Evidence is provided of a clear relationship between EB and the blood metabolites NEFA and BHB, especially in the transition period.