Poultry producers are working to reduce antibiotic use and maintain performance. Intestinal health is important for overall animal health, especially as antibiotics are removed. Because there may be multiple reasons for improved performance when antibiotics are used a feed additive with multiple modes-of-action may help maintain intestinal health and animal performance as antibiotics are removed.
By Amlan International
Poultry producers are working to reduce antibiotic use while sustaining poultry performance. They are turning to feed additives to help offset decreased feed efficiency and increased mortality caused by removing antibiotics. Over the years several things have been suggested as reasons for improved performance when antibiotics were fed: decreased clinician and subclinical disease; less overall intestinal bacteria load; decreased inflammation in the intestine and the body as a whole; as well as others. The true reason for the positive effect of antibiotics on animal performance is unknown and it is probably a combination of any or all of the reasons suggested. So looking at feed additives with multiple modes-of-action may be a way to sustain performance as antibiotics are removed.
A lot of the benefits that feeding antibiotics have provided probably start in the intestine. The intestine has two major functions. It lets good things (i.e. nutrients) into the body while at the same time keeping damaging things (i.e. toxins, bacteria) out of the body. Any damage to the absorptive function will have a direct negative impact on feeding performance. Second, the mucus layer, the enterocytes (cells lining the intestine) and the sub endothelial immune tissue (the GALT) form an intestinal barrier that is responsible for maintaining the health of the animal and development of the immune system. The intestinal barrier is under constant assault from bacteria, viruses, parasites, and toxins of all types. In the case of many diseases that decrease animal performance, toxins either enter the body after being ingested in the feed (i.e. mycotoxicosis) or damage the intestine directly (i.e. alpha or NetB toxins produced by Clostridium perfringens). In many cases the damage caused is due to these toxins. Toxins can enter the intestine through the feed or water, or they can be exotoxins or endotoxins produced by resident bacteria. Overall, these toxins can be called biotoxins. If there is interaction of a toxin or toxins with an endothelial cell, reduced nutrient absorption function or death of the cell and subsequent loss of intestinal integrity may be the result. Therefore, a feed additive based on controlling biotoxins but with added benefits to the intestine might help sustain poultry and livestock production even as producers are working to limit antibiotics that have had beneficial results since first introduced to animal agriculture in the 1940’s.
Several controlled trials have successfully shown that a commercial product based on controlling biotoxins can have equivalent performance to antibiotics with or without a planned bacterial challenge. Because of this a poultry producer in southern Brazil conducted is large-scale study to determine the benefits of this product at the commercial level. The study used approximately 180,000 broilers from three farms. Each farm fed one house a control diet with their standard feed, which contained a mycotoxin binder and enramycin. A second house on each farm was fed a diet where the antibiotic and the mycotoxin binder were removed, and a feed additive was included. The feed additive was developed to control biotoxins, both fungal and bacterial, but also to provide energy to the epithelial cells lining the gastro-intestinal tract and prepare the immune system for future challenges.
The chicks that were supplied to the farms for evaluation were from breeders of the same age. Every week a sample of approximately 1% of the birds were weighed in each barn and the mortalities in each barn were tabulated. Birds were harvested at 47.29 days for the control birds and 47.17 days for the birds fed the feed additive. Daily weight gain was similar between the two treatments with 69.60 g for the control birds and 70.62 g for the additive fed birds.
Overall feed conversion was 1.717 for the control birds and 1.671 for the birds fed the additive; an advantage for birds fed the additive of 4.6 points (Figure 1).
Weekly mortality, cumulative mortality, and transport mortality were all lower when birds were fed the additive compared to those fed the antibiotic (Figure 2).Because weight gain was maintained when compared to the standard diet and replacing the antibiotic and binder showed improvements in feed efficiency and morality there was also an economic improvement to the producer when the additive was used. This commercial study shows that feeding the additive with multiple modes-of-action can improve efficiencies and performance, which are critical to increasing profits. In this case, the added annual profit for a producer processing 1 million birds per week would equate to approximately USD 6 million. Using an estimated price for the control diet of USD 375 and USD 380 for the additive diet, the return on the cost of the additive vs the antibiotic control diet is approximately 4 to 1.
The results from this commercial trial confirm the previous research. The commercial trial showed that feeding an additive with multiple-modes-of action can help sustain performance when an antibiotic is removed from the diet.
