Advanced chelate compounds technology is a novel technology that introduces a new generation of chelates to deliver trace elements better by polymerization of organic acids. In the present study, the over-supplementation effect of Bonzaplex7 supplement, which is designed based on the aforementioned technology, was evaluated on milk yield of dairy Holstein cattle through two experiments. In the first experiment (exp. I), 24 primiparous dairy cows were randomly assigned to one of 3 groups: (1) without over-supplementation (control); (2) daily allowance of 7 g/cow Bonzaplex7 containing Co (12 mg), Cr (3.5 mg), Cu (126 mg), Fe (56 mg), Mn (196 mg), Se (2 mg), and Zn (357 mg) (Bonzaplex7); and (3) daily allowance of the same amounts of all of the trace minerals in amino acid complex form (AA). In the second experiment (exp. II), 170 multiparous dairy cows received either 7 g/day/cow Bonzaplex7 (85 cows, test) or no additional supplement (85 cows, NS). In exp. I, the milk yields in control, Bonzaplex7, and AA were 34.30, 36.46, and 35.83 kg/day, respectively (P = 0.528). No significant differences in milk composition were detected among the groups. In exp. II, however, higher milk fat and energy-corrected milk yield were observed in test compared with NS. Both Bonzeplex7 and AA elevated the plasma concentrations of Cu, Mn, and Se. The results provided evidence that supplementing dairy cows with a combination of trace minerals which produced using the advanced chelate compounds technology has a potential to improve milk fat and to decrease disease susceptibility under stressed conditions.
