Micromanagement: Trace minerals in layers

Not all micronutrients are created equal when it comes to layer diets. The mineral source, inorganic or organic, impacts the availability of the nutrients to laying hens. Trouw Nutrition, that includes the Shur-Grain brand in Canada, has completed a new research study to evaluate the impact of adjusting mineral sources on layer performance.

“We wanted to see if we could move the needle a little on mineral nutrition in layers, and maybe egg shell quality, by adjusting the combination and sources of some of our micronutrients,” says Mark Malpass, director of technology application for poultry with Trouw.

Malpass points to the fact that research has already clearly demonstrated that the source of trace minerals impacts how “available” they are for layers to access from the diet. On a spectrum, inorganic sources of minerals like copper, zinc and manganese are the least bioavailable for birds. Minerals that are hydroxy based are midway and more bioavailable. And organic sources are the most bioavailable, and the most expensive.

“We have a good offering of micronutrients in our layer premixes that balance performance and producer returns, but we always want to challenge ourselves about how we can use these ingredients differently or combine them in slightly different ways to be more effective.”

Trouw recently completed a 40-week trial at its layer validation farm in Ontario to see if adjusting the mix of some of the trace minerals – and combinations of inorganic and organic sources – would improve layer performance. “Our validation farms provide a real-world commercial style setting where we can conduct scientific research,” Malpass says.

Higher return
Using 12,000 Dekalb layers, they compared their standard feeding program that already contains a mid-level of bioavailable copper and zinc, to a diet with more bioavailable, organic trace mineral sources of zinc and manganese.

“What we found is that the partial replacement of inorganic trace minerals with more bioavailable sources led to better productivity and a higher return on producer investment,” Malpass says. “And we’re now looking for opportunities to implement these micronutrient changes to commercial feeds across Canada.”

The partial replacement of zinc and manganese with more bioavailable sources, combined with a reduction in overall levels of levels of copper and manganese, resulted in: lower bird mortality; higher average daily egg production  and egg mass; higher revenue and profit; and no difference in feed costs per bird.

These productivity improvements were achieved without impacting feed efficiency, indicating that layers were more productive because they were able to use the micronutrients more efficiently.

So, more isn’t always better. “We are always trying to balance the use of micronutrients,” he says. “Adding more isn’t necessarily the goal, it’s about the optimum mix that improves bird performance and producer ROI.”

Shell quality unchanged
The research also evaluated the impact of micronutrient adjustments on shell quality – including shell thickness, breaking strength and egg yolk height. Surprisingly to Malpass, the switch to more organic, available nutrients didn’t alter shell quality.

“I think what this part of the research confirms for us is that we are already doing pretty well with providing premixes that optimize shell quality for layers that include a mid range of bioavailable minerals,” Malpass says.