Transition period in healthy and diseased dairy cows: evaluation of metabolic modifications
Riferimento:Large Animal Review 2018; 24: 107-111
Abstract:Introduction - The time from late pregnancy to early lactation is known as transition period and is characterized by a metabolic stress that leads to a high incidence of metabolic, infectious, and reproductive disorders associated with a severe negative energy balance (NEB). During the period of NEB there is an increase of lipolysis and a decrease of lipogenesis causing a striking increase of blood levels of βhydroxybutyrate (BHB) and non-esterified fatty acids (NEFA). Moreover, an alteration of several blood metabolites including urea, calcium, magnesium, glucose and insulin concentrations is typical during NEB in association with increased hepatic gluconeogenesis. Inflammatory conditions during the transition period may cause a shift in liver protein synthesis, including a marked reduction in albumin and cholesterol serum concentrations. Aim - The aim of this study was to evaluate the changes of Body Condition Score (BCS) and some haematochemical parameters in healthy and diseased high yielding dairy cows during the transition period. Moreover, the relationship between glucose, βhydroxybutyrate (BHB) and non-esterified fatty acids (NEFA) in healthy and diseased high yielding dairy cows was evaluated during the transition period. Materials and methods - Blood sampling and BCS values were collected from 24 dairy cows 15 ± 5 days prepartum (T0), 10 ± 2 days postpartum (T1), 30 ± 2 days postpartum (T2) and 50 ± 2 days postpartum (T3). On blood samples, serum glucose, BHB, NEFA, total proteins (TP), albumin, globulins and urea concentration was evaluated. Two way repeated measure analysis of variance (ANOVA) and Person’s correlation test were applied on obtained data. Results and discussion - A significant BCS loss during the postpartum in both groups was found. The decrease of glucose values and the increase of NEFA and BHB values were found suggesting the difficulty of dairy cows to cope with the energy demand. Serum TP, albumin and globulins values were higher during the lactation than prepartum. Serum urea values showed significant differences during the different physiological phases. Conclusions - Our data contributed to improve the knowledge on changes of some blood metabolite concentration during the transition period for a deeper interpretation of clinical data and an easier diseases diagnosis in high yielding dairy cows.