Removing Trace Minerals and Vitamins in Late Finishing can Save $1 Per Pig

As feed costs remain high, the search for ways to save every penny continues.Recent research has focussed on removing vitamins and trace minerals in late finishing as a means of decreasing cost without compromising performance.

In three separate experiments, vitamins and trace minerals were removed between three and five weeks prior to market. Results conclusively showed that there was no effect on animal performance or carcass characteristics.

One experiment, carried out at Prairie Swine Centre with 525 pigs, concentrated on testing an appropriate timeframe for removing the premix from the ration. They found that it did not matter if vitamins and trace minerals were removed at 3 or 5 weeks prior to market, there was no effect on performance or carcass quality in either case.

The other two studies, completed at Kansas State University with 128 and 160 pigs respectively, examined the effect of taking out different components of the ration. In the first study the vitamins, trace minerals, or both were removed from the ration. In the second study the vitamins and trace minerals, 66% of the inorganic phosphorus, or all three components were removed from the ration. They found no significant difference between treatments in performance or carcass characteristics in both cases.

Dr. Ron Ball, a professor in Animal and Poultry Science at the University of Guelph was "really surprised that they did not see an effect" of removing trace minerals and vitamins. He suspected that removing vitamins and minerals from the ration would contribute to a "lack of nutrients to metabolize protein and energy". Dr. Kees de Lange, also a professor in Animal and Poultry Science at the University of Guelph, admits that "the facts are pretty clear" but he also has some major concerns.

Dr. de Lange is concerned that by removing trace minerals and vitamins "we may be compromising welfare of the animals". Dr. Ball echoes this concern and notes that there is a lot of evidence that marginal nutrient deficiencies affect the immune system. Dr. Ball suggests that pigs fed rations deficient in vitamins and trace minerals could be "at greater risk of disease outbreaks just before market when they have a great deal of value" and may be less resistant to other kinds of stresses, like environmental stress or transport stress.

Kansas State University reports that "many poultry producers are drastically reducing, and sometimes completely omitting, vitamins and trace mineral premixes just prior to slaughter to reduce cost of gain". They suggest that a short period exists where removing vitamins and minerals would have no effect on performance and carcass characteristics, because body stores would be sufficient to last until slaughter.

As pigs grow, their requirements as a percentage of the ration decrease. Minimum standards set by the National Research Council sometimes do provide generous safety margins. As a result, dietary excesses in late finishing are common. Researchers at Kansas State University suggest that since these excesses are excreted as waste, reducing trace minerals and vitamins will make livestock operations more environmentally friendly.

| Top of Page |

Dr. de Lange points out that it is illegal to remove premixes because the mineral and vitamin levels in the ration would drop below the legal minima which have been set out by Agriculture and Agri-Food Canada. He stresses that a commercial feed company could not tell their customers to stop using premix one month prior to market, but admitted that it is unclear what would happen if an individual producer tried it on his own.

Dr. de Lange is adamant that "we have to be concerned with the wholesomeness of the meat" and if the minerals and vitamins are withdrawn from the feed it's quite clear to him that "the level of nutrients in the product we are trying to sell would also be reduced". In their report, Prairie Swine Centre does admit that the picture is not yet complete. The impact of removing these nutrients on pork products has not yet been determined but they have a project underway to look at that issue.

While they represent a smaller portion of the total feed bill than expensive protein and energy sources, minerals and vitamins still represent a significant expense. Prairie Swine Centre estimated that removing the vitamin and trace minerals from the ration would reduce the cost of feed by $6-12 per tonne, depending on the level of inclusion.

Prairie Swine Centre suggests that removal of trace minerals and vitamins "may be an effective way to reduce the cost of production without affecting animal performance or well-being", estimating a typical savings of approximately $1/pig sold. Prairie Swine Centre does caution that they would not recommend removing premixes for animals that are kept for breeding purposes.

Dr. de Lange suggests that "the fact that pigs do not reduce performance when we withdraw vitamins and minerals from the last month's diet... might be... a reflection that we overfeed earlier in life, so we might be much better off just feeding less overall and coming up with the same savings". If he were looking for ways to save costs, he would focus more closely on phosphorus requirements of the finishing pig approaching market weight because "that's where the bang for the buck is". That is also where you can get around many of his concerns while at the same time dealing with many environmental issues that we may face in the future.

In terms of the applicability of these results in Ontario, Dr. de Lange is "skeptical about the results of Prairie Swine Centre because they are based on western diets which are more barley-based". He believes that since corn-soy diets create more concerns about vitamin E and meat quality, we should pay more attention to the results from Kansas State University, where the rations used are more representative of our situation.

| Top of Page |