Organic zinc is key to improved environment

Supplementing commercial broiler birds with organic zinc rather than inorganic zinc can lead to far better outcomes, especially in terms of environmental impact, delegates at the conference were told.

According to James Pierce, associate director of research for Alltech in the USA, there has been a dearth of research into the subject of mineral supplementation.

While the genetic progress for poultry has increased massively over the last 30 years in terms of production, reproduction and health, much of the understanding of trace mineral requirements remains stuck in the 1950s and 1960s, based on the limited research of that era, he said.

But Dr Pierce has recently studied inorganic versus organic zinc and, by using the latter, discovered that the traditional recommended doses are far in excess of what is actually needed today.

Research at the University of Kentucky, Lexington, with 500 Cobb males over 42 days, fed on a corn-soya diet, found that birds require 9.8ppm of organic zinc (Bioplex zinc) compared to the industry standard of 40ppm of inorganic zinc (zinc sulphate).

This was good news in today’s environmentally sensitive era as birds that are fed less organic minerals excrete less, he explained.

These findings were backed by further research at the University of Guelph, Canada, on 288 Ross X males, again fed on a corn-soya diet with up to 80% less organic minerals than inorganic.

At the lowest level of organic mineral supplementation, they excreted 38% less zinc, 52% less manganese and 21% less copper. Yet this and other studies showed no significant change in the performance of the birds.

Broiler producers and nutritionists in regions where ground water pollution is a problem could utilise organic minerals in poultry diets, rather than inorganic, to reduce the risk of contamination, without compromising performance, said Dr Pierce.

Egg production

Similar benefits have been observed in egg production. Research using 768 Shaver white pullets looked at the effects of using full dosage of inorganic trace minerals, a 15% dosage of inorganic minerals and a 15% dosage of organic (Bioplex) minerals.

There was a significant reduction in the excretion of minerals using the organic minerals, but no difference in terms of bodyweight, feed intake, egg numbers or egg mass.

Egg size was reduced late in lay when low levels of inorganic minerals were fed. However when low levels of organic minerals (Bioplex) were fed, egg size was not reduced, said Dr Pierce.

His overall conclusion was that using organic minerals at up to 80% less than would be used with inorganic minerals maintains bird performance, with no increase in mortality and with much reduced mineral excretion.

“With current technologies in trace mineral supplementation, we can now feed trace minerals in amounts far less than ever deemed possible because we’re feeding them in the form nature intended,” he told the conference.

“By doing that, we also reduce the oxidative stress on the animal, improve feed efficiency, and most importantly we have a lower environmental impact.”

Dr Pierce encouraged producers to check with feed suppliers about changing from inorganic to organic trace minerals in smaller concentration. The use of a “step-down” programme, with higher levels in starter diets going down to lower levels at the end of the production, had also proved to be cost effective in trials.