Effect of dietary administration of Mentha piperita alone and in combination with Artemisia abrotanum on growth performance, body composition, physicochemical properties and amino acid composition of meat in Eimeria-challenged broilers

This study aimed to evaluate the effects of dietary administration of peppermint (Mentha piperita) alone and in combination with southernwood (Artemisia abrotanum) on performance, body and carcass composition, physicochemical characteristics, and amino acid composition of breast meat in broilers under Eimeria challenge. A total of 160 14-day-old male broilers (Ross 308) were randomly assigned to four dietary groups: the control (C) group was fed a basal diet; the CC group received a grower diet containing the coccidiostat robenidine; the M group was fed the diets with the addition of 20 g peppermint/kg of diet; the MS group was fed the diets with the addition of 10 g peppermint + 10 g of southernwood/kg of diet. The addition of peppermint to the diet increased final live weight compared to the CC group (P < 0.05). The highest value of dressing percentage was found in the M group as compared to the CC group (P < 0.01) and C group (P < 0.05). Compared with the C group, a higher intramuscular fat content was found in the breast meat of broilers in both the M and MS groups (P < 0.01; P < 0.05, resp.). Concerning the colour of meat, lower values for yellowness b* and chroma C* characteristics were observed in the C group compared to the MS group (P < 0.05) and mainly to the M group (P < 0.01). In spite of the lower crude protein content (P < 0.05) in the meat of the MS group, the highest content of all essential amino acids (P < 0.05) as well as the total content of all assessed amino acids (P < 0.01) were found in the meat of the MS group, resulting in a considerable increase in the nutritional value of the breast meat proteins of these broilers.