NADP negatively correlates with insulin resistance indices, the glucose to insulin ratio (GLU:INS) and RQUICKI and positively with TBIL, GGT, ALB and LFI values in cows receiving niacin, while in the control group cows showed a negative correlation with GGT and a positive correlation with urea (Table 3, Figure 4). This evidence concerns the gene INS and Insulin resistance.