Thirty healthy Friesian cows that were chosen in the late pregnancy period for this study. Three groups of ten cows each were formed from the experimental cows. Cows in 1st without L-carnitine supplement served as a control group (G1), and supplemented with L-carnitine supplementation 2 and 4g/cow/day in the 2nd (G2) and 3rd group (G3), respectively from 20 days pre-calving until 3 days post-calving. A significant improvement of L-carnitine supplemented diets on counts of red (RBC's) and white blood cells (WBC's) and concentration of hemoglobin (Hb) in cows. The haematological values of treated cows were greater than those of the control group. The immunological response of the treated cows was greatly enhanced by the L-carnitine treatment. Treated cows were significantly highest lymphocytes in G3 and reduced monocytes than in G1. The levels of total proteins, triglyceride and HDL (high-density lipoprotein) in blood plasma were higher in G3 than in G2 and G1. However, cholesterol, lipoprotein, and LDL (low-density lipoprotein) concentrations were significantly decreased in G3 and G2 than in G1. Immunoglobulins IgG, IgA and IgM concentrations on different days of cows were significantly higher in G2 and G3 than in G1 in newborn calves.
Treatment with L-carnitine level of 4g/head/day improved the immune response of treated cows. As well as L-carnitine improved the IgG and IgA, IgM and total Ig concentrations in plasma of newborn calves with high levels of L-carnitine.