The data on Deoni dams and their HF × D halfbreds (F1) from CCBP and ACDF over a period of 21 years were considered for the investigation. In all 193 Deoni dams and 193 HF × D halfbreds were included in the study. The evaluation of AFC and MY and effect of farm, season and period on it was studied. The LSM for AFC arid MY for Deoni dams and HF × D halfbred were 1777.64 ± 50.24 days and 499.75 ± 9.02 kg and 1281.30 ± 42.98 days and 1623.32 ± 19.44 kg, respectively. The farm and period effects were non-significant on AFC in Deoni dams, whereas it was highly significant (P < 0.01) in HF × D halfbreds. The effect of season was non-significant in Deoni and HF × D halfbred. The farm and period had highly significant (P 0.01) effect on MY in Deoni, but the season had non-significant effect. In halfbreds, the farm, season and period significantly (P 0.01) affected the milk yield.