Comparison of trace mineral repletion strategies in feedlot steers to overcome diets containing high concentrations of sulfur and molybdenum

Trace mineral concentrations in Canadian beef calves at weaning

Objective

To describe the copper and selenium statuses of beef calves at weaning.

Animal

Calves (n = 1998) were sampled from 106 Canadian cow-calf herds in the fall of 2021.

Procedure

Serum samples from calves were tested for copper, selenium, and molybdenum concentrations.

Results

Although the percentages of calves classified as selenium deficient (< 0.025 ppm) were relatively low (0.5% western Canada, 3% eastern Canada), 53% of calves from western Canada and 77% of calves from eastern Canada were classified as having less than adequate selenium concentrations (< 0.08 ppm). Copper deficiency (< 0.5 ppm) was common in calves from both western (17%) and eastern (14%) Canada. High molybdenum concentrations (> 0.10 ppm) were identified in 6% of calves from western Canada and 7% of calves from eastern Canada.

Conclusion

Selenium concentrations were higher in calves from western Canada than from those in eastern Canada (P < 0.001). Copper and molybdenum concentrations were not significantly different between western and eastern Canada. Less-than-adequate serum copper was the most common deficiency identified in Canadian beef calves at weaning.

Clinical relevance

Trace minerals are important for immune system function in calves at weaning. Selenium concentrations in calves at weaning were lower than in cows from the same herds collected at pregnancy testing 2 y earlier. Copper deficiency was also identified, though less frequently than for mature cows. Supplementation programs for calves should be customized based on testing and recognize both regional and age differences in risk.

The combined effect of ultrafine particles of cobalt and manganese oxides and Origanum vulgare herb extract on ruminal digestion in vitro

Background and Aim

At present, detailed studies are being conducted to confirm the safety of the use of metal-containing ultrafine particles (UFP) in animal feeding, preventing the possibility of negative effects on productive qualities and physiological state, as well as on the environment and final consumer, that is, humans. Thus, the purpose of this research was to study the safety of cobalt- and manganese-containing UFP (UFP Co3O4, Mn2O3 UFP) together with Origanum vulgare (PB) herb extract in a bioluminescence inhibition test, as well as the effect of this composition on ruminal digestion in vitro.

Materials and Methods

The safety of the studied samples was determined using a multifunctional microplate analyzer TECAN Infinite F200 (Tecan Austria GmbH, Austria), recording the luminescence value of the bacterial strain Escherichia coli K12 TG11 (Ecolum, JSC NVO Immunotech, Russia). Dry matter (DM) digestibility studies were performed using the in vitro method on an "artificial rumen" model using an ANKOM Daisy II incubator unit (AD II; USA). The number of protozoa in ruminal fluid was counted in a Goryaev chamber. The bacterial mass was assessed by differential centrifugation followed by drying. This method is based on differences in the sedimentation rate of particles that differ in size and density.

Results

UFP Co3O4 and Mn2O3 at concentrations above 1.5 × 10-5 and 1.9 × 10-3 mol/L, respectively, have a pronounced bactericidal effect, suppressing more than 50% of the luminescence of E. coli K12 TG1. The combined use of UFP metals and plant extract increases the luminescence of the test object, indicating its safety. The combined use of UFP and PB increases the digestibility of feed DM in vitro and the number of protozoa in 1 mL of ruminal fluid; however, the combination of UFP Mn2O3 + PB (13.8%) yielded the best result, which is recommended for further in vivo research.

Conclusion

Origanum vulgare extract reduces the toxicity of UFP Co3O4 and Mn2O3 in vitro, indicating that their combined use is safer.

A Trace Mineral Injection before Joining and Lambing Increases Marking Percentages and Lamb Weights on Diverse Farms in Victoria, Australia

This study was conducted on five commercial farms across Victoria, Australia, between September 2018 and November 2019, where the TM status of ewes was within normal ranges before joining. Mix breed ewes (n = 1484) were randomly allocated to receive either nil treatment (Control) or two injections of an ITM product containing zinc (40 mg/mL), manganese (10 mg/mL), selenium (3 mg/mL), and copper (10 mg/mL); 0.2 mL per 10 kg BW (Multimin® plus Copper for Sheep, Virbac (Australia) Pty Ltd., Milperra, NSW, Australia) 30 days before the start of joining and 30 days before the start of lambing. Approximately 90 days after joining, pregnancy status and conception rate were determined by ultrasound. The marking rate was determined approximately four weeks after the end of lambing, and lamb weights were determined at weaning (12 weeks after the end of lambing). In all farms, ITM treatment did not affect the conception rate. The average conception rate was 156 ± 11.0% (p > 0.05). The marking rate of ITM ewes was 9% higher than control ewes (95% Confidence Interval 3−21%). Lambs born to ITM ewes were 2.31 kg heavier at weaning than lambs born to control ewes (p < 0.001). Although not significant, ewe mortality across farms was 1.3% lower in the ITM group than in the control group. On average, ewes treated with ITM pre-joining and pre-lambing produced more and heavier lambs that represent an extra AU$ 2338 per 100 ewes net benefit for the producer. These results help to understand strategic TM supplementation for animal health, performance and farm profitability beyond the treatment of clinical deficiencies.

Trace Elements in Beef Cattle: A Review of the Scientific Approach from One Health Perspective

The objective was to investigate the context, approach and research topics present in the papers that analysed trace elements in beef cattle to identify gaps and scientific perspectives for the sustainable management of trace elements in livestock. The main research groups came from the United States, Spain, Japan, Brazil, India and Slovakia, which represented 31% of the papers produced. Only 37% of studies addressed aspects that integrated animal, environmental and human health. The reviewed papers concerned 56 elements and 15 bovine tissues (Cu, Zn, Pb, liver, muscle and kidney highlighted). The main gaps were (1) lack of research in developing countries, (2) the need to understand the impact of different environmental issues and their relationship to the conditions in which animals are raised, and (3) the need to understand the role of many trace elements in animal nutrition and their relationship to environmental and human health. Finally, we highlight possible ways to expand knowledge and provide innovations for broad emerging issues, primarily through expanding collaborative research networks. In this context, we suggest the adoption of the One Health approach for planning further research on trace elements in livestock. Moreover, the One Health approach should also be considered for managers and politicians for a sustainable environmental care and food safety.

Effects of a single trace mineral injection at beginning of fixed-time AI treatment regimen on reproductive function and antioxidant response of grazing Nellore cows

Two experiments evaluated the effects of injectable trace minerals (ITM) administered 11 d before artificial insemination (AI) on body weight (BW), body condition score (BCS), ovarian structures, pregnancy rate, and antioxidant response of Nellore cows. In Experiment 1, 20 multiparous cows were assigned to one of two treatments: subcutaneous injection (6 mL/cow; 11 d before AI) of saline solution or ITM (60, 10, 5, and 15 mg/mL of Zn, Mn, Se and Cu, respectively) and BW, BCS, ovarian structures and blood were evaluated. In Experiment 2, 1,144 multiparous cows were assigned to same treatments described in Experiment 1 and pregnancy rate on d 30 was evaluated. In Experiment 1, ITM did not affect (P ≥  0.23) BW, dominant follicle size, ovulation rate, and plasma concentrations of haptoglobin, ceruloplasmin and progesterone (P4). The ITM treatment tended to increase (P =  0.06) cow BCS and reduce (P ≤  0.06) corpus luteum (CL) diameter and volume. Furthermore, ITM treatment tended to increase (P =  0.06) plasma concentrations of SOD and increased (P =  0.007) GSH-Px compared with saline injection. In Experiment 2, ITM treatment tended (P =  0.06) to increase pregnancy rate of cows with BCS ≤ 5.0 but not cows with BCS > 5.0 (P =  0.99). The ITM treatment did not alter BW, plasma P4, and acute phase response, but enhanced plasma concentrations of antioxidant enzymes, and tended to enhance BCS and pregnancy rates to AI of cows with BCS ≤ 5.0, even though there was a smaller corpus luteum size.