The Impact of Feeding Organic Trace Minerals Using Advanced Chelate Technology on Reproductive Efficiency and Blood Parameters in Ghezel Ewes

BACKGROUND: The bioavailability of trace minerals (TM) in a diet is important for improving reproductive performance and fertility parameters. OBJECTIVE: This study evaluated the effects of replacing inorganic trace minerals (ITM) with organic trace minerals (OTM), formulated using advanced chelate technology, on the reproductive performance and blood attributes of ewes. METHODS: Forty ewes were subjected to a five-week intervention in four dietary groups (n = 10): (1) OTM: flushed with organic trace minerals (Bonzaplex-7); (2) ITM: flushed with inorganic trace minerals; (3) NTM: flushed without adding trace minerals; and (4) CON: grazed only on pasture. Oestrus synchronization was performed based on two doses of 75 µg cloprostenol with 12 days interval + 400 IU eCG injection. The number of follicles and pregnancy were determined by ultrasound. Blood samples were collected at predetermined time points during the experimental period (Days 0, 11, 14 and 34). RESULTS: OTM (80%) and ITM (90%) groups exhibited higher first-cycle pregnancy rates, as well as improved lambing and twinning rates. OTM demonstrated the greatest efficiency across all reproductive indices. However, follicle number was not affected by the treatments. Also, T3 and T4, as well as triglycerides, were higher in the OTM group as compared with other groups (p < 0.05). Serum estradiol, progesterone and antioxidant enzymes were not affected by treatments (p > 0.05). CONCLUSIONS: Overall, supplementing advanced chelate technology-based OTM in the flushing diet improved the reproductive performance of ewes.