Source Matters: Manganese Supplementation Impacts Dairy Cow Performance
When it comes to trace mineral research, manganese oftentimes plays second fiddle to other essential trace minerals, such as zinc and copper. The truth is that manganese is a vital trace mineral and plays an important role in overall cattle nutrition.
Manganese is a cofactor for enzymes that are involved in fat metabolism, carbohydrate metabolism and energy production, and it is critical to cattle health as an antioxidant. Additionally, as a cofactor in the production of cholesterol, manganese is essential to reproductive performance.
Manganese is also responsible for the production of glycoproteins, which are precursors for connective tissue and bone formation. Therefore, a severe manganese deficiency in dry cows can result in their offspring having inadequate bone formation (weak, deformed legs).
Above and Beyond NRC Recommendations
The 2001 NRC recommendation for manganese in adult dairy cattle is approximately 14 to 20 ppm. The NRC recommendation considers body weight, milk production and manganese absorption rate (approximately 0.75%) as well as growth and pregnancy status. The recommendation does not consider the presence of antagonists such as iron, stressful conditions (like heat stress and the transition period), the presence of mycotoxins in the feedstuffs or any other factors that could reduce manganese absorption or increase a cow’s manganese requirements.
A study by Weiss and Socha in 2005 determined that the manganese requirements were 1.6 and 2.7 times greater than NRC recommendations for lactating and dry cows, respectively. Supplementation must be provided to prevent such shortfalls.
For optimal cattle performance, we recommend feeding 55 to 75 ppm of supplemental manganese as part of an effective nutrition program. A portion of the supplement should be from Zinpro Performance Minerals®. Feeding higher levels and more bioavailable sources of manganese can result in improvements in animal performance and health.
A recent research study revealed that feeding higher levels of manganese from performance trace minerals reduces the prevalence of milk fever in dairy cows, which can also lead to reductions in mortality.
The 2017 study, conducted on a large commercial dairy in Central Valley, California, evaluated how manganese from Availa®Mn can impact animal health and performance when supplementation was increased from 9 to 20 ppm in lactating dairy cattle diets. The study took place from 30 days pre-partum to 200 days in milk production and included 156 primiparous and 573 multiparous Holstein cows that were fed one of two diets:
9 ppm Supplementation: A total of 60 ppm of manganese was supplemented to each cow with 51 ppm of inorganic manganese from manganese sulfate (MnSO4) and 9 ppm of manganese from Availa-Mn (n=356). This supplementation rate of performance trace minerals has been our standard recommendation for many years.
20 ppm Supplementation: A total of 60 ppm of manganese was supplemented to each cow with 40 ppm coming from MnSO4 and 20 ppm from Availa-Mn (n=373).
All the cows were housed in free-stall facilities, with primiparous and multiparous cows housed in separate pens prior to calving. All cows received the same level of supplemental manganese in the total mix ration (TMR) trace mineral base mix, with the additional manganese from MnSO4 or Availa-Mn administered orally with 50 mL of molasses on an individual basis. Health assessments were performed daily, and milk tests included evaluations of milk fat yield, true protein and somatic cell count.
Performance Trace Minerals Reduce Milk Fever and Mortality
Milk yield, energy corrected milk, milk components, somatic cell count and reproduction parameters were similar between cows fed 20 ppm vs. 9 ppm of manganese from Availa-Mn. However, cows fed 20 ppm of manganese from Availa-Mn had a 50% reduction in the prevalence of milk fever compared to cows fed 9 ppm. Only 2.1% of cows fed 20 ppm of Availa-Mn were treated for milk fever, compared to 4.2% of cows receiving 9 ppm.
The culling risk did not significantly differ between the two groups, but cows fed 20 ppm of manganese from Availa-Mn had a 62% reduction in death risk compared to 9 ppm. The immune system, when activated, utilizes a lot of calcium. So as manganese improves immune function and reduces milk fever, a dairy producer may experience less death loss on their operation. Cows fed 9 ppm of manganese from performance trace minerals had a 6.1% death loss compared to only a 2.3% death loss for cows fed the higher amount.
We also saw that the impact of the manganese supplementation was immediate upon the onset of lactation. Of the cows that were fed 9 ppm of manganese from Availa-Mn, 85% of those that died, did so in the first 30 days in milk. Of the cows that were fed 20 ppm of Availa-Mn, 57% of the death loss was experienced in the first 30 days in milk.
A Healthy Return on Investment
Based on 2020 economics, feeding 20 ppm vs. 9 ppm of manganese from performance trace minerals resulted in a return on investment that exceeded 5-to-1 through lower replacement costs.
We can clearly see in the study the value of not only increasing your manganese supplementation level, but also ensuring a higher level of that supplementation is from a more bioavailable source like performance trace minerals.
To learn more about the value of including Availa-Mn in your dairy cow nutrition program, contact your Zinpro representative today.