Pig Performance and the Economics of Long-Term Feeding of DON-Contaminated Diets
Feedstuffs used for swine diets are often contaminated with mycotoxins. This continues to be a problem as they affect pig performance and can have a negative impact on their health. Deoxynivalenol (DON), also known as vomitoxin, commonly contaminates wheat, corn, barley and other feed ingredients. In North America, 90% of finished feed samples contained DON. The fusarium mould that produces DON is increasing in incidence throughout Saskatchewan, with DON contamination downgrading 80-90% of wheat. Avoiding the use of this feed is no longer a viable option, so strategies are being researched to deactivate the mycotoxin. So far these strategies appear to be ineffective or only work for certain mycotoxins. Swine are the most susceptible livestock species to DON and there are currently no additives available in Canada to mitigate this problem. As most studies done have been completed on younger animals for a short period of time, long term effects on grower-finisher pigs were investigated. If fed over 1 ppm DON, average daily gain, body weight and feed intake all decreased, though finisher pigs had much less pronounced results. Over time, it seems that the pigs are able to adapt to DON intake between 1 to 5 ppm, though the reduction in body weight persists. When fed high levels of DON in complete diets, the pigs weigh 5 – 8 kg less by market weight and consume less total feed. In order to not change the margin over feed cost with this decreased weight, DON-contaminated feed should be discounted and introduced in the finisher period. Reduced feed intake is the main cause for the negative effects of DON consumption as health status, carcass quality and nutrient utilization are not effected negatively.