Background and Aim: Milk yield (MY) is one of the main factors that affect the economic profitability of dairy farms.
Thus, increasing the MY per animal and decreasing the feed cost can lead to economic gains, so the objective of this study
was to evaluate the effect of dry period length (DPL), days open (DO), and days in milk (DIM) on the productivity and
profitability of dairy cow farms.
Materials and Methods: Data used in this study were taken from 3095 lactation records of Friesian dairy cows of private and
governmental sectors. The data were classified into 4 DPL categories: DPL1 75 days, 3 DO categories: DO1 ≤90 days; DO2 91-110 days and DO3 >111 days, and 8 DIM categories: DIM1
180-210 days; DIM2 211-240 days; DIM3 241-270 days; DIM4 271-300 days; DIM5 301-330 days; DIM6 331-360 days;
DIM7 361-447 days; and DIM8 >447 days.
Results: The average net profit (NP) was significantly different (p |
