Investigations on effects of different diet compositions on the quality of excreta in fattening turkeys with special emphasis on Clostridium perfringens prevalence

During this study, it was investigated whether a certain diet composition (i.e. higher digestible starch- and protein sources) beginning from the feeding phase 3, could influence the composition of excreta and counts of Cl. perfringens in the excreta. The counts of Cl. perfringens in excreta were determined weekly in clinically healthy animals. It should be clarified whether there are some relations between diet compositions, changes in excreta quality (found in visual analysis) and counts of Cl. perfringens. For this purpose a fattening trial (a total of 2,080 fattening turkeys) with one control and three experimental groups were carried out under field conditions in one research farm. After an identical 5-week rearing period in which the animals were fed with the same diet (conventional complete feed), the young turkeys were divided into four groups with different feeding concepts from fattening phase P3 to P6. The different diet compositions had no considerable effects on excreta parameters. Independent of diet composition, the age of the animals (resp. fattening phase) had a significant influence on dry matter contents in excreta: it increased from 160 (P3) to 202 (P6) g/kg fresh weight. The bacteriological investigations in combination with a visual appraisal of excreta quality show that foamy and liquid excreta in turkeys do not indicate a massive load with Cl. perfringens; in those samples even lower counts than in normal excreta were detected. The highest counts of Cl. perfringens were observed in excreta containing litter and undigested feed. Hence, a use of expensive ingredients in higher proportions in the diets for fattening turkeys is to be recommended only after an intensive costs/use analysis. Factors like the age of the animals or the general management are presumably more important than type and proportion of ingredients that should respect the upper limits of certain types of ingredients as shown in the control diet.