Dietary organic trace mineral supplement affects steroid hormone, antioxidant enzyme concentrations, and reproductive performances in dairy cows

Supplementation of organic trace mineral (OTM) may affect reproductive functions in several aspects and has been studied, but very rare is reported dairy cows. To determine the effects dietary OTM supplement during pre- postpartum with timed artificial insemination (TAI) protocol on steroid hormones, antioxidant enzymes, performances Prepartum Holstein cows (n = 60) were randomly assigned to received either a control diet or supplemented for 42 days. Both groups fed same total mixed ration, 5 g/head/d (Bioplex®) treatment group. Blood follicular fluid samples collected progesterone (P4), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), estradiol (E2) concentrations. Cows had better placental expulsion period, milk yield, performance parameters (day first ovulation estrus, percentage estrus size preovulatory follicle) than (P < 0.05). affected 0.05) serum concentration P4 days 12, 15, 18, 21, after TAI. Follicular concentrations E2 large follicle greater (336.3 376.9 ng/mL; P SOD GSH-Px activities (15.5 vs. 10.6 U/mL 12.1 9.9 U/mL; In conclusion, supplements improved uterine health, hormones concentrations, enzyme did not improve conception rate