Impact de l’incorporation des feuilles de patate douce dans l’alimentation sur les performances zootechniques des poulettes et la qualité sanitaire de la viande

Abstract

Poultry feed accounts for a significant portion of production costs and competes with human food for conventional raw materials, affecting profitability and food security. The use of local resources, such as sweet potato leaves, is a sustainable alternative. This study aimed to evaluate the effect of incorporating sweet potato leaf meal on the zootechnical performance and carcass quality of pullets. The experiment was carried out from July to October 2024 at the FABI teaching farm, University of Burundi, in Gitega. It involved 80 three-week-old chicks, randomly divided into four groups of 20 subjects each. The control group received a conventional diet, while the experimental groups received a diet with partial protein replacement with sweet potato leaf meal at 5%, 10%, and 15%. The zootechnical results showed that the average individual feed intake was similar between the groups, with 81.6 ± 0.6 g/day for the control group, 81.6 ± 0.9 g/day for group 2, 81.6 ± 0.4 g/day for group 3, and 81.6 ± 0.8 g/day for group 4. However, the overall average live weight decreased progressively from one group to the next, from 1535.6 ± 10.6 g for group 1 to 1485 ± 41.7 g for group 2, then to 1442.9 ± 32.7 g for batch 3 and 1400.9 ± 39.8 g for batch 4. This trend was also observed for average daily gain, which decreased from 16.6 ± 0.2 (batch 1) to 15.7 ± 0.2 g (batch 2), then to 14.8 ± 0.5 g (batch 3) and 14.0 ± 1.5 g (batch 4). The overall consumption index increased gradually with the incorporation rate, from 3.1 ± 0.1 in the control batch to 3.1 ± 0.1 in batch 2 (5%), then to 3.4 ± 0.2 in batch 3 (10%) and 4.7 ± 0.1 in batch 4 (15%), reflecting a decrease in efficiency at the highest incorporation levels. No mortality was recorded in any of the batches throughout the entire period. In terms of health, the meat did not contain Escherichia coli or Salmonella, and the total mesophilic aerobic flora was well below regulatory limits. Cadmium levels were <0.5 mg/kg, while lead ranged from 1.51 to 1.86 mg/kg, exceeding the regulatory limit. In conclusion, the incorporation of sweet potato leaf meals at up to 5% did not significantly affect growth performance or the microbiological quality of the meat and is an interesting local alternative in poultry feed.