Influence of Dietary Addition of Dried Wormwood (Artemisia sp.) on the Performance and Carcass Characteristics of Hanwoo Steers and the Nutrient Digestibility of Sheep

Two experiments were conducted to study the performance and carcass characteristics of Hanwoo (Korean native beef cattle) steers (Experiment 1) and the nutrient digestibility of sheep (Experiment 2) when the animals fed diets containing four levels of dried wormwood (Artemisia sp.). For both experiments the animals were given a basal diet consisting of rice straw and concentrate mixed at 3:7 ratio (on DM basis). In Experiment 1, the treatments were designed as a completely randomized design with two feeding periods. Steers were allotted in one of four dietary treatments, which were designed to progressively substitute dried wormwood for 0, 3, 5 and 10% of the rice straw in the basal diet. Bodyweight gain and average daily gain (ADG) of Hanwoo steers fed diets containing the 5 and 10% wormwood inclusion were greater (p<0.05) than the 3% wormwood-feeding group. Total and daily intakes of roughage and concentrate were not altered by all levels of dried wormwood inclusion. However, the 10% dried wormwood inclusion led to increased total feed intake (p<0.05) compared with that of the 0 and 3% of dried wormwood inclusion. Carcass weight, carcass yield and backfat thickness were not altered by dried wormwood inclusion. The highest level of dried wormwood inclusion resulted in significantly increased (p<0.05) loin-eye area compared with the 0 and 5% levels of dried wormwood inclusion. Experiment 2 was designed by a $4{\times}4$ Latin square with four periods. Sheep were allocated in one of four dietary treatments as same as in Experiment 1. Digestibilities of DM and TDN were significantly increased (p<0.05) in sheep fed the diet containing all three levels of dried wormwood inclusion compared with the control treatment. Digestibilities of CP and crude fiber in the 5% dried wormwood inclusion highly increased (p<0.05) up to 8.2 and 5.5% respectively relative to the control treatment. The palatability was significantly improved (p<0.05) by the 5% dried wormwood inclusion compared with the control treatment. It is concluded that feeding diets containing dried wormwood substituted for equal weights of rice straw at 5 and 10% levels would be anticipated to provide better quality roughage for beef cattle production and higher income for beef cattle producers.