SUMMARY
The purpose of this study was to determine the macro minerals concentration in serum of repeat breeding (RB) Aceh cattle. In this study 16 Aceh cattle were examined; they consisted of 7 fertile Aceh cattle (P1) and 9 Aceh cattle with RB (P2), all of which were 3-8 years old with abody condition score (BCS) of 3-4. Serum collection was carried out for examining the level of serum minerals, including magnesium, phosphorus, sodium, potassium, chloride, and calcium. Data was analysed using T-test. The levels of magnesium, phosphorus, sodium,potassium, chloride, and calcium in P1 vs P2 were 2.18±0.60 vs. 2.20±0.34 mg/dL; 6.18±1.34 vs. 6.48±0.74 mg/dL; 142.71±5.09 vs.142.44±2.29 mmol/L; 4.81±0.76 vs. 4.76±0.51 mmol/L; 104.57±4.35 vs. 107.67±7.36 mmol/L; and 9.07±0.45 vs. 9.90 ± 0.60 mg/dL (P>0.05), respectively. It was concluded that the concentration of serum macro minerals do not affect the incidence of RB in Aceh cattle.