A research project at the Auburn University in the United States has found a potential link between feeding distillers dried grains with solubles (DDGS) and necrotic enteritis in broilers.
DDGS is commonly being used by the poultry industry. The objective of the research, led by Dr Kenneth Macklin, was to determine the role, if any, of DDGS in necrotic enteritis development.
The research found that high levels of DDGS (15%) can amplify mild to moderate cases of necrotic enteritis into more severe cases. It also shows that even with a mild case of necrotic enteritis, bird live performance is more negatively impacted in those birds fed DDGS versus those that were not.
Two experiments were performed:
Birds were fed a standard corn soy diet that had either 7.5 or 15 % DDGS included in the diet. The birds were then challenged, first with a coccidia cocktail and then four days later with Clostridium perfringens over three consecutive days. Ten days after the coccidia cocktail was administered, the birds were necropsied. During the necropsy necrotic enteritis and coccidiosis lesions were scored, and samples were collected for C. perfringens recovery. In addition, feed conversion, body weight and mortality data were collected.
Using the results from the first study, a second experiment was performed using the most detrimental level of DDGS (15%) and three different challenge levels (low, medium and high) of C. perfringens. The goal of this experiment was to determine if DDGS influenced the severity or incidence of necrotic enteritis development with these three different levels of C. perfringens. The same experimental measurements were collected in this experiment as in the first.
The first experiment did not clearly define the relationship between feeding DDGS and necrotic enteritis development. What was obvious, though, was that the treatment group fed the 15% DDGS diet had a significantly worse 15-28 day adjusted feed conversion ratio (AFCR) than the group fed the diet that did not contain DDGS. Though not significant, the group fed the intermediate DDGS diet (7.5%) had six points higher AFCR than the group fed the control diet. This is important because the 15-28 day period is when the birds were challenged with coccidia and C. perfringens.
Based on these as well as previous results from the labs, it was concluded that 15% DDGS was more likely to have an effect on necrotic enteritis development. In the second experiment similar differences were seen in the 15-28 AFCR, with the groups fed the 15% DDGS diet having higher AFCR values than similarly challenged birds fed a diet containing no DDGS. Not surprisingly, the birds fed either diet (0 or 15% DDGS) that were not challenged had similar AFCR.
Also in that experiment birds that were fed the 15% DDGS diet and challenged with the low and medium dose of C. perfringens had more severe necrotic enteritis lesions then those that were not fed a diet with DDGS. Both groups given the high challenge doses had a similar number of cases of severe necrotic enteritis lesions. These results show that high levels of DDGS may lead to decreased bird performance. When the birds have a mild to moderate C. perfringens challenge, this can lead to more severe cases of necrotic enteritis as well as a decrease in bird live performance.
The project, funded by the USPoultry and the USPoultry Foundation, is part of the Association's comprehensive research programme encompassing all phases of poultry and egg production and processing.
A complete report may be obtained by going to USPOULTRY's website.