The role of minerals in rumen digestion

When working to maximize the effectiveness of rumen digestion within your herd, your selection of the right trace mineral program can have a positive impact on rumen digestion, while improving the availability of essential trace metals to the animal.

Optimizing rumen digestibility is a very high priority when working to maximize the productivity, efficiency, and sustainability of high performing dairy herds around the world. Work conducted by M. Oba and M.S. Allen, Michigan State University found that a one point increase in NDF digestibility (NDFd) was associated with a 0.17 Kg (0.37 lb.) increase in DMI and a 0.25 Kg (0.55. lb.) increase in 4% fat corrected milk. Translated into economics, this would indicate that a one point increase in NDFd within a 100 cow herd could represent an additional 9,125 Kgs of saleable milk per year with a gross value of €3,650 (@40 eurocents/Lt).

DIFFERENT FACTORS INFLUENCE NDFd
There are many factors impacting NDFd in the lactating cow, such as forage quality, ration formulation and quality, cow well-being, genetics, etc… But what about the source of trace minerals used in your herd’s trace mineral supplementation program? Multiple, independent research investigations have now shown that the source of trace minerals can play an important role in maintaining optimized NDFd within the herd. An initial study conducted by M.J. Faulkner & W.P. Weiss, the Ohio State University found a 2.9 point increase (p<.02) in NDFd (43.0 vs. 45.9) when they completely replaced the use of copper, zinc and manganese sulphate with hydroxy trace minerals (Selko^® IntelliBond^® Z, C and M) in a conventional, high forage, TMR. This finding has prompted many researchers from around the world to further investigate this outcome resulting in a significant number of studies being completed and published to date. In 2022 M. Ibraheem & B. Bradford, Michigan State University finalized a comprehensive meta-analysis of 11 similar comparisons (See Figure 1) designed to evaluate the replacement of sulphate trace minerals with Selko^® IntelliBond^® Z, C and M. Overall results indicated that the full replacement of the sulphate trace mineral supplement program provided an NDFd increase of 1.66 points (p<.02).

PICKING THE RIGHT TRACE MINERAL
Research shows, when selecting a trace mineral program for your herd, you should not assume that all sources of trace minerals are alike. A recent study completed by Fermentrics^® Technologies, Inc. compared multiple trace mineral sources of zinc and manganese. Results indicated that Selko^® IntelliBond^® M resulted in a significant improvement in apparent microbial biomass production (aMBP) compared with a methionine analog chelate, sulphate, oxide and amino acid complex sources of manganese. Results for Selko^® IntelliBond^® Z indicated a similar effect producing a significantly greater improvement (p<.04) in aMBP when compared with control, a methionine analog chelate, amino acid complex, OHTM and sulphate treatments. These results (see Figure 2) would support the assumption that Selko^® IntelliBond^® is able to better optimize the rumen environment relative to other trace mineral sources resulting in improved rumen digestibility and aMBP.

STABILITY IN EVERY MOLECULE
Above and beyond the impact of trace mineral source on rumen digestibility, a key consideration to keep in mind when selecting a source of trace mineral nutrition for your herd is the stability of your trace mineral source and its bioavailability within the cow. Issues like reoccurring stress (transition, environmental and metabolic) and peak performance require that top performing cows have consistent access to a highly available source of trace minerals that are capable of effectively delivering essential trace metals to the cow when she needs them most. Multiple studies (Spears et. al., etc.) have clearly shown the ability of Selko^® IntelliBond^® to deliver a higher level of bioavailability relative to the use of sulphate and or oxide trace minerals sources.

GOING BEYOND DIGESTIBILITY
Also important in today’s industry is the need for all ration ingredients, additives, and supplements to show they are working within the cow to lower her carbon footprint. Based on independent research results Selko was successful developing an independently verified LCA for use in dairy cows resulting in up to a 2% reduction in the cow’s carbon footprint per kg of energy corrected milk. Of greatest value is the fact that this benefit is free when using Selko^® IntelliBond^® to optimize rumen digestibility and trace metal availability within the cows. In addition to this important verification, Selko has recently achieved the verification of an additional LCA, which accurately identifies the carbon footprint for Selko^® IntelliBond^® C, Z and M (see Figure 3). This independent verification positions the Selko^® IntelliBond^® source of trace minerals as the first trace mineral source to offer nutritionists, formulators, and producers an accurate CO₂eq value to use when working to reduce the carbon footprint of premixes, feeds, and rations in use within your herds nutritional program.

In conclusion, when working to maximize the effectiveness of rumen digestion within your herd, your selection of the right trace mineral program can have a positive impact on rumen digestion, while improving the availability of essential trace metals to the animal. Based on the data reviewed from Michigan State a 1.66 point increase in NDFd gained from the replacement of sulphates could result in an additional 15,000 Kgs of 4% fat corrected milk per 100 cows.