Effects of Enriched Charcoal as Permanent 0.2% Feed-Additive in Standard and Low-Protein Diets of Male Fattening Turkeys: An On-Farm Study

SIMPLE SUMMARY: Improving animal welfare, animal health and environmental issues is important in modern animal farming. In fattening of male turkeys, footpad dermatitis is a very frequent problem. Reducing faecal moisture is one way of controlling one source of footpad dermatitis. Therefore, in the present study, conducted under on-farm conditions, we added 0.2% enriched charcoal (known as a household remedy in therapy of diarrhoea and microbial imbalances) to the diet. Additionally, in a second experiment, the protein content of the diet was reduced by 1% from weeks 6–13 of life to slow down the growth rate and to reduce nitrogen in the litter. Three farms were visited four times during the fattening period to collect data on the birds. The charcoal-supplemented diet showed no effects on the performance of the birds or the examined health parameters. The protein-reduced and charcoal-supplemented diet did not influence the final bodyweight or the footpad status but reduced the mortality during the fattening period by 0.5%. In conclusion, enriched charcoal as 0.2% feed additive does not improve animal health, welfare or performance. Hence, a diet with temporarily reduced protein shows beneficial effects on the mortality rate and has no negative influence on the final body weight. ABSTRACT: Wet litter is the most important cause of footpad dermatitis in poultry, this in turn being a highly relevant animal-related welfare indicator. This field study was subdivided into two experiments. In Experiment 1, the standard diet was supplemented by 0.2% enriched charcoal, being a non-specific absorber and therefore might be promising in reducing faecal moisture. In Experiment 2, the experimental group received a reduced crude protein diet during weeks 6–13, combined with a 0.2% enriched charcoal supplementation. The trials were each conducted with two batches on three farms under on-farm conditions. The animals were observed at 6, 10, 14 and 18 weeks of age to collect data on body weight and different health parameters. The mortality and litter samples were analysed after slaughtering. In Experiment 1, performance and health were not affected despite higher dry matter content of the litter. In Experiment 2, the weight of birds receiving the protein-reduced diet was decreased significantly throughout the experiment. However, the slaughter weight did not differ. The mortality was reduced by 0.5% in the experimental group. Therefore, it was concluded that 0.2% of enriched charcoal is not a valuable feed-additive regarding animal health, while temporary protein reduction might have positive effects.