Twenty clinically healthy goats were divided into two equal groups based on two different diets. Goats in group A were fed with 25 % barley, 12 % oat, 15 % faba bean, 10 % pea, 20 % sugar beet pulps, 5 % molasses and 3 % mineral. Goats in group B were fed with 25 % corn, 15 % soybean hulls, 12 % soybean meal, 10 % sunflower meal, 20 % sugar beet pulps, 5 % molasses and 3 % mineral. To establish the effect of diet composition on haematological and biochemical concentrations, blood samples were collected from the external jugular vein once a week, for 1 month (T0-T4), twice daily (0700 and 1800 hours). Multivariate analysis of variance (MANOVA) showed a significant effect of different diets (P < 0.01) and periods (P < 0.001) on serum total protein and urea concentrations. Also, a significant effect of time of day (P < 0.001) was observed on urea serum concentration. In conclusion, different diet composition had an influence on serum total protein and urea concentrations. A diet with 25 % corn induce an increase of serum total protein concentration and a decrease of serum urea concentration compared with a diet with 25 % barley.