This study was conducted to determine the effect of inclusion of fever tea (Lippia javanica) leaf meal in broiler diets on growth performance, carcass characteristics and fatty acid (FA) profiles over a 42-day feeding period. One hundred and eighty, one-day-old, broiler chicks were randomly allocated to the following four treatments: 1) negative control (commercial broiler diet only [Negcontrol]); 2) positive control (commercial broiler diet + prophylactic antibiotics [Poscontrol]); 3) commercial broiler diet without prophylactic antibiotics + 5 g of L. javanica per kg of feed (Ljav5) and 4) commercial broiler diet without prophylactic antibiotics + 12 g of L. javanica per kg of feed (Ljav12). Body weights (BW) and feed intake (FI) were recorded weekly and used to calculate feed conversion ratio (FCR) and average daily weight gain (ADG). At the end of the trial (day 42), all chickens were slaughtered at a local commercial abattoir for assessment of carcass characteristics and FA profiles of meat. The broilers fed L. javanica had significantly (P < 0.05) lower FI compared with the other two groups. However, the broilers in the Poscontrol and Ljav5 treatment groups had higher (P < 0.05) ADG, lower FCR and higher slaughter weights. L. javanica inclusion had no effect on the breast weight, thigh weight, carcass weight, and dressing percentage of the broilers. Most of the n-3 FA were not affected by diets except for the docosapentaenoic, which was found to be higher (P < 0.05) in the Ljav12 treatment group and the lowest in the Negcontrol. The broilers in the Negcontrol and Poscontrol groups had higher (P < 0.05) total saturated fatty acids (SFA). On the contrary, the L. javanica fed broilers had higher (P < 0.05) total polyunsaturated fatty acids (PUFA), total n-3 FA and PUFA:SFA ratio and also had significantly lower n-6:n-3 ratios compared with the other two treatment groups. No differences were observed with regards to total monounsaturated fatty acids (MUFA) and total n-6 FA. Overall, the findings from the study showed that inclusion of L. javanica in broiler diets at 5 g/kg feed has positive influences on growth performance, carcass characteristics and FA profiles of broiler meat.
Keywords: Average daily gain; Carcass weight; Fatty acids; Feed conversion ratio; Fever tea.