RESUMEN
Blood and milk samples were collected weekly, throughout a complete month, from five normal lactating cows kept in the farm of Fac. Vet. Med. [Beni-suef]. At the day of sample collection a blood sample was collected from each animal. At the normal time of milking in the morning, samples representing fore and striped milk were collected separately from each animal. Besides another sample from whole drown milk was taken from each cow. Urea, creatinine, alanine amine transferase [ALT] and asparate amine transferase [AST] activities as well as concentrations of total and direct bilirubin were determined in serum, fore milk, stripping and whole drown milk. The levels of urea, creatinine, ALT and AST activities were significantly higher [P< 0.01] in milk than in serum. Moreover, ALT and AST activities were significantly increasing [P<0.01] towards the last portions of drown milk. While, there is no difference in the concentrations of bilirubin in serum and milk