A study assigning 1021 lactations of 313 Bulgarian Murrah buffalo cows with milk yield recorded on the farm of Agricultural Institute – Shumen during the period 1967-2001 was initiated with the objective to estimate the effect of days open on the milk yield and the duration of the con

The effect of pregnancy on milk yield in Bulgarian Murrah buffalo cows P. Penchev, Y. Ilieva, Tz. Peeva