Subclinical necrotic enteritis (NE) is an economically important enteric disease caused by a netB producing, Gram-positive, anaerobic bacterium, Clostridium perfringens. Massive intestinal proliferation of C. perfringens is promoted by increased availability of free amino acids. The Fusarium mycotoxin eoxynivalenol (DON) is a common feed contaminant with a maximum guidance level set at 5000 ?g/kg feed (2006/576/EC) and may damage intestinal epithelial cells and/or their intercellular junctions, subsequently inducing protein leakage (Girish and Smith, 2008) and may thus predispose to the development of NE.
A highly reproducible in vivo infection model mimicking subclinical NE was used
(Gholamiandehkordi et al., 2007). A total of 360 one-day-old Ross 308 broilers from a commercial hatchery were randomly divided into four groups of three replicates with 30 birds per replica. All birds were fed a starter diet during the first eight days of the experiment, subsequently a grower diet for eight days, followed by a finisher diet during the remaining days. Throughout the entire experiment, group 1 and 4 received a blank diet while group 2 and 3 received an experimentally contaminated diet with DON. All birds in group 1 and 2 were challenged orally with one ml of a culture of C. perfringens strain 56 containing approximately 4 x 108 cfu/ml for four consecutive days starting at day 17. The remaining groups received sterile medium orally. The contamination level of DON and other mycotoxins was assayed using a validated multi-mycotoxin LC-MS/MS method (Monbaliu et al., 2010).
The blank feed contained DON at 75 ± 22 ?g/kg (starter), 83 ± 24 ?g/kg (grower)
and 100 ± 29 ?g/kg (finisher). The contaminated feed contained DON at 3761 ± 1100 ?g/kg (starter), 4281 ± 1300 ?g/kg (grower) and 4384 ± 1300 ?g/kg (finisher). At 1, 2 or 3 days after the final challenge with C. perfringens, chickens were euthanized and scored macroscopically for intestinal NE lesions. Chickens that received DON and C. perfringens had significantly (alpha=0.05, P<0.001) more lesions than chickens that received only C. perfringens, with 46.6% and 19.5% of chickens positive for NE lesions, respectively. No NE lesions were seen in the groups receiving no C. perfringens inoculations.
Feeding DON contaminated feed in concentrations lower than the maximum guidance contamination level of 5000 ?g/kg to broilers is a predisposing factor for the development of NE.
|Publicatiestatus||Gepubliceerd - 28-mrt-2012|
|Evenement||First IHSIG International Symposium - Gent, België|
Duur: 28-mrt-2012 → 29-mrt-2012
|Symposium||First IHSIG International Symposium|
|Periode||28/03/12 → 29/03/12|