The aim of this study was to characterize the metabolic status of specialized and dual-purpose dairy cows under lowland tropical dairy systems in Colombia, by evaluating body condition, serum concentrations of metabolites and hormones, in the transition period and up to 105 days post-partum, through multivariate analysis techniques. To understand the joint variation of hormones and metabolites evaluated during the experimental phase, the 21 variables under study (haemoglobin, haematocrit, NEFA, BHB, glucose, cholesterol, triglycerides, urea, protein, albumin, globulin, AST, ALT, GGT, body condition, T3, cortisol, insulin, leptin, prolactin, GH), were analysed from a multivariate approach. A cluster analysis and principal component analysis (PCA) were performed to reduce the dimensionality of the information, and to identify the representative variables to explain the variation in the dat...

The effect of energy and protein densities of diets on homeostasis, metabolic profile and productive performance during pre and postpartum periods of Romosinuano cows was evaluated. Thirty grazing cows were assigned to three nutritional supplementation groups: TC: 0.0, T1: 2.35 and T2: 2.8 kg/animal/day of energy-protein supplement. The experiment ran from 30 days before calving to 60 days postpartum. Body weight (BW), body condition (BCS) and serum concentrations of glucose, cholesterol, total protein, β-hydroxybutyrate, non-esterified fatty acids (NEFAs), urea, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were evaluated. The prepartum supplementation did not affect BW (p=0.4557) nor BCS (p=0.1893). In the postpartum period, there was a significant effect of supplementation on BW (p=0.0343) and BCS (p=0.029) in T1 and T2 and on glucose at prepartum in T2 (p=0.001...