The objective of this study was to evaluate the nutritional composition (fat, total protein, casein, defatted dry extract, total solids and vitamin A), refractometry and pH of Jersey cow colostrum and correlations between Brix degree and colostrum constituents. Colostrum samples were collected from Jersey cow in the fifth milking after calving. Samples were identified and refrigerated until analysis. Data were subjected to analysis of variance and a descriptive analysis, while differences between milk were compared by the Duncan’s test (P < 0.05) using the SAS version 9.0 software program. Pearson correlations were then performed between Brix grade and bovine colostrum constituents. The fat, total protein, casein, total solid and Brix percentage of the colostrum gradually decreased from the first to the fifth milking, while the lactose content increased. Positive correlations were observed between Brix values and protein, casein, total solids and defatted dry extract contents, while lactose was negatively correlated. The rapid reduction in Brix means and protein concentrations after delivery demonstrates the importance of administer colostrum in the shortest period after birth. © 2021 Friends Science Publishers