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 toevaluate the effects ofdietary administration ofpeppermint (Mentha piperita) alone and incombination with southernwood (Artemisia abrotanum) onperformance, body and carcass composition, physicochemical characteristics, and amino acid composition ofbreast meat inbroilers under Eimeria challenge. Atotal of160 14-day-old male broilers (Ross 308) were randomly assigned tofour dietary groups: the control (C) group was fed abasal diet; the CCgroup received agrower diet containing the coccidiostat robenidine; theMgroup was fed the diets with the addition of20g peppermint/kg ofdiet; the MSgroup was fed the diets with the addition of10g peppermint+ 10g ofsouthernwood/kg ofdiet. The addition ofpeppermint tothe diet increased final live weight compared tothe CCgroup (P<0.05). The highest value ofdressing percentage was found intheMgroup ascompared tothe CCgroup (P<0.01) and Cgroup (P<0.05). Compared with the Cgroup, ahigher intramuscular fat content was found inthe breast meat ofbroilers inboth the M and MSgroups (P<0.01; P<0.05, resp.). Concerning the colour ofmeat, lower values for yellowness b* and chroma C* characteristics were observed intheCgroup compared tothe MSgroup (P<0.05) and mainly tothe Mgroup (P<0.01). Inspite ofthe lower crude protein content (P<0.05) inthe meat ofthe MSgroup, the highest content ofall essential amino acids (P<0.05) aswell asthe total content ofall 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.