Background
- Trace minerals play an important role in cattle immunity, health and performance.
- Copper, selenium, zinc and manganese deficiencies are known to negatively influence beef cattle reproduction.
- Delivery of supplemental trace minerals using an injectable solution has been demonstrated to be a reliable means of achieving adequate trace-mineral status.
The aim of the study was to summarise fertility results obtained in Brazilian beef cattle injected with a combination trace mineral solution before fixed-time artificial insemination (FTAI), compared with non-treated control animals.
Materials and methods
- 7 farms in Brazil: 6 in Goiás and 1 in Mato Grosso do Sul.
- 1,643 Nelore cattle: 350 nulliparous, 206 primiparous and 1,087 multiparous cows.
- Randomised treatment: MM (n = 816) versus control (CON, n = 827).
- Period: December 2022 to April 2023.
- Parity and body condition score (BCS) did not differ among treatment groups.
- Treatment: Zn 60 mg/ml, Mn 10 mg/ml, Cu 15 mg/ml, Se 5 mg/ml (Multimin 90®, Axiota Animal Health).
- Protocol: treatment on day 0, synchronisation using estradiol and a progesterone-releasing intravaginal device, FTAI on day 11, pregnancy diagnosis on day 41.
Results
Pregnancy at day 41 was 51% in the MM group versus 44% in controls.
| Farm | MM | Control |
|---|---|---|
| Farm 1 | 48% | 42% |
| Farm 2 | 43% | 30% |
| Farm 3 | 47% | 40% |
| Farm 4 | 54% | 48% |
| Farm 5 | 54% | 47% |
| Farm 6 | 64% | 60% |
| Farm 7 | 39% | 34% |
Accounting for farm, parity and BCS, MM animals had 1.29 greater odds of pregnancy compared with controls (OR 1.29; 95% CI 1.05–1.59). Treatment-by-parity and treatment-by-farm interactions were not significant.
| Subgroup | Odds ratio | 95% CI |
|---|---|---|
| BCS < 3 | 1.19 | 0.93–1.53 |
| BCS ≥ 3 | 1.49 | 1.02–2.17 |
The benefit was larger in animals with adequate body condition. In the BCS < 3 subgroup the confidence interval crosses 1, so a difference cannot be established for those animals.
Conclusions
A combination trace mineral injection applied at the beginning of the synchronisation protocol can be beneficial for fertility in beef cows. The magnitude of the benefit can be amplified in cows with adequate BCS, where energy might not be a limiting factor for reproduction.
This page is a transcription of the poster above, prepared so that the full results — including the subgroup where no difference could be established — are readable, searchable and accessible without opening the PDF.
Study funded by Axiota Animal Health, manufacturer of Multimin® 90. Four of the authors are employees of the company.
Multimin® is available by prescription only through licensed veterinarians. Consult the approved label for complete directions, warnings and pre-slaughter withdrawal.