July 4, 2007

 

Seeking a sustainable "Trace element footprint" for livestock production systems

 

Press release
 

 

"Trace element footprint" is a phrase set to enter the lexicon of animal micro-nutrition following its introduction at the inaugural Organic Trace Elements for Animal Nutrition and the Environment (OTEANE 2007) symposium. Sponsored by Pancosma, the two-day, 20-speaker, 200-delegate event took place in Geneva from Jun 14-15, 2007.

 

Up on the agenda were environmental issues arising from trace element supplementation, copper and zinc in particular, in animal production.

 

European Commission guidelines for the authorisation of feed additives are currently under revision, with spring 2008 set as the target period for introduction.

 

Specific requirements for environmental risk assessments would require concentrations of heavy metals, dioxins and PCBs in trace element supplements to be measured. The Commission's broad intention was to reduce maximum permitted levels of legitimate trace elements as well as contaminants.

 

The environmental rationale for this was clear, according to soil scientist Dr Jeffrey Novak from the United States Department of Agriculture. "Copper and zinc are cations, and when they are applied to soils in slurry or manure, they look for anions with which to bind," he said.

 

Over a 10-year period of pig manure application, plant-available copper levels in soil analysed by Dr Novak increased from 0.48 to 3.37 ppm. The total copper content rose from 1.25 to 8.52 ppm. For zinc, the plant-available proportion changed from 1.69 to 7.42 ppm and the total zinc content, from 8.10 to 20.09 ppm. For soybean crops, phytotoxicity was reached in the range of 12 to 20 ppm of copper.

 

Dr Novak commented that animal production faced the issue of having most copper and zinc supplementation to pigs coming "back out of the tail-pipe." Such an effect was more acute in areas of confined animal feeding operations, especially for pigs and poultry. 

 

OTEANE seeks to provide a sustainable trace element footprint for animal production systems, while promoting good animal health, welfare and performance through appropriate use of organic trace elements, according to Pancosma.

 

Wageningen Academic Publishers will publish full proceedings from OTEANE later this year. Meanwhile, an abstracts booklet is available from: www.pancosma.com

 

 

For further information, e-mail: oteane@vtx.ch