Increasing feed efficiency means that more milk is being produced out of the same amount of feed. This will reduce the environmental footprint of the dairy farm because the amount of greenhouse gasses per liter of milk produced will go down. Next to reducing the environmental footprint, improving feed efficiency of dairy cows will also increase the income over feed costs, making dairy farming more profitable. Whereas in beef, swine and poultry farming, feed efficiency is the most commonly use performance indicator, dairy farmers often use milk production and the amount of milk solids produced to measure the performance of the farm. As a result, potential gains in feed efficiency often go unnoticed.

Feed efficiency in lactating dairy cows can vary from <1.3 to >2.0. As a result, the income over feed costs and the environmental footprint of dairy farming can vary enormously between dairy farms. There are several factors that have an impact on feed efficiency of dairy cows such as:

• Digestibility of feed
• Milk production
• Feed intake
• Days in milk
• Forage quality
• Forage quantity
• Age of the cows
• Protein level of the ration
• Somatic cell count
• Body weight change
• Fat percentage of the milk
• Rumen acidosis
• Environmental stress
• The amount of exercise and grazing
• Pregnancy
• The use of certain feed additives

Out of those factors, digestibility of the feed is one of the most important ones. In ruminants, a well-functioning rumen is key to ensure maximum digestibility of feed. Trace mineral management can have a serious impact on rumen function and thus on digestibility of the diet of dairy cows.

The negative impact of sulphate salts on the rumen microflora reduces their ability to digest fibre, in term resulting in a reduction of feed efficiency. Multiple studies carried out by different independent research groups[2,3,4,5,6,7,8,9] have proven that completely replacing sulphate trace minerals with IntelliBond will avoid high levels of metal ions being present in the rumen. This will result in a significant improvement of fibre digestibility (see Figure 2). A meta-analysis of all studies carried out with IntelliBond showed an average improvement of NDF digestibility of 1.7%[10]. University research in dairy cows has shown that each one point difference in NDF digestibility can represent an extra 0.25 to 0.3 kg of daily Energy Corrected Milk production[11].

In a trial carried out by Cornell University[13], milk production was increased in early lactation cows fed IntelliBond compared to cows fed sulphates. (see Figure 3). The IntelliBond group reached peak production sooner and produced 3.5 liters milk more at the peak of lactation. Dynamics of lactation persistency in dairy cows indicate that 1 kg of extra milk at peak lactation is equal to 200 kg of extra milk per lactation. A more recent study by Daniel et al[8] confirmed that dairy cows fed IntelliBond will have a significant increase in milk production.

1. Caldera, C.E, Weigel, B, Kucharczyk, V.N, Sellins, K.S, Archibeque, S.L, Wagner, J.J, Han, H, Spears, J.B. and T.E. Engle (2019). Trace mineral source influences ruminal distribution of copper and zinc and their binding strength to ruminal digesta. J. Anim. Sci., 97:1852-1864.
2. Faulkner, M.J. and W.P. Weiss (2017). Effect of source of trace minerals in either forage- or by-product-based diets fed to dairy cows: 1. Production and macronutrient digestibility, Journal of Dairy Science 100:5358-53-67.
3. Miller, M.D, Lanier, J.S, Kvidera, S.K, Dann, H.M, Ballard, C.S. and R.J. Grant (2020). Evaluation of source of corn silage and trace minerals on lactational performance and total-tract nutrient digestibility in Holstein cows. J. Dairy Sci., 103:3147-3160.
4. Guimaraes, O, Jalali, S, Wagner, T, Spears, J and T. Engle (2019). The influence of trace mineral source on fiber digestion, rumen fermentation characteristics, and mineral solubility in beef cattle fed a low-quality forage diet. J. An. Science. 97, Issue Supp. 3: 167.
5. Guimaraes, O, Wagner, T, Spears, J and T. Engle (2020). Influence of trace mineral source on digestion, ruminal volatile fatty acid and soluble mineral on steers fed a dairy type diet balanced to meet requirements for a high producing lactating dairy cow. J. An. Science. 98, Issue Supp. 3: 133–134.
6. Caldera, C.E, Weigel, B, Kucharczyk, V.N, Sellins, K.S, Archibeque, S.L, Wagner, J.J, Han, H, Spears, J.B. and T.E. Engle (2019). Trace mineral source influences ruminal distribution of copper and zinc and their binding strength to ruminal digesta. J. Anim. Sci., 97:1852-1864.
7. Genther, O.N. and S.L. Hansen (2015). The effect of trace mineral source and concentration on ruminal digestion and mineral solubility. J. Dairy Sci., 98: 566-573.
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9. Van Kuijk, S, Swiegers, P and Y. Han (2022), Hydroxychloride trace minerals improve apparent total tract nutrient digestibility in Bonsmara beef cattle. Livestock Science: 256(4):104820.
10. Ibraheem and Bradford, Michigan State University 2020, personal communication.
11. Oba, M. and M.S. Allen (1999). Evaluation of the Importance of the Digestibility of Neutral Detergent Fiber from Forage: Effects on Dry Matter Intake and Milk Yield of Dairy Cows. J. Dairy Sci., 99:589-596.
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13. Yasui, T, Ryan, C.M, Gilbert, R.O, Perryman, K.R. and T. R. Overton (2014). Effects of hydroxy trace minerals on oxidative metabolism, cytological endometritis, and performance of transition dairy cows. J. Dairy Sci. 97: 3728-3738.14)
14. Lee, C, Copelin, J.E. and M.T. Socha (2022). Effect of zinc sources and experimental conditions on zinc balance in growing wethers. Animal Science.