This study was carried out on 270 calves (199 heifers and 71 bulls) that were crosses of Black-and-White and Holstein-Friesian (HF) cattle, with the HF gene pool of 25.0–97.8%. At the age of 2 days blood samples were collected, and assayed for the concentrations of immunoglobulins, total protein, albumins, glucose, urea, total cholesterol and hemoglobin. The hematocrite number was also determined. Crossing with HF decreased the concentration of albumins, glucose and cholesterol, and increased the concentration of urea (P ≤ 0.01). Heritability coefficients, estimated using mother-calf regression were very low for immunoglobulins (0.056) and protein (0.006), and slightly higher for some metabolites (0.148 for albumins and 0.204 for cholesterol). The results indicate that in the genetic improvement of crosses with HF or purebred HF cattle aimed at increasing of calf vigor, the potential for colostrum intake should be a primary selection trait.

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