The aim of this study was to evaluate the effects of two different diets on fertility rate in 64 Mediterranean buffalo cows. The animals were divided in two groups: Group S (n=32) received a total mixed ration based on haysilage of Italian ryegrass (Lolium multiflorum), hay and concentrates, whereas group H (n=32) was fed only hay and concentrates. Both diets consisted of 50-55 % forages and 45-50 % concentrates and contained 0.91 MFU/kg dry matter (DM) and 16% crude protein/DM. From February until September the cows were located together with bulls and pregnancy diagnosis was performed monthly. Furthermore, blood and milk samples were monthly collected on 20 animals in each group. Statistical analysis was performed by χ2 and t Student test...