Effects of forage level and chromium-methionine chelate supplementation on performance, carcass characteristics and blood metabolites in Korean native (Hanwoo) steers

다국어 초록 (Multilingual Abstract)

A feeding trial was carried out to determine the effects of chromium methionine (Cr-Met) chelate and forage level over two years, $1^{st}$ fattening and $2^{nd}$ fattening period on growth parameters, carcass characteristics and blood metabolites of 46 Korean native (Hanwoo, Bos Taurus, $BW=183{\pm}44kg$) steers. Treatments were: 1) Steers in the low forage (LF) group were fed diets that consisted of 60% concentrate and 40% forage; 2) Steers in the high forage (HF) group were fed diets that consisted of 40% concentrate and 60% forage. Following the $1^{st}$ fattening period, steers ($BW=480{\pm}37.6kg$) were randomly assigned to four treatment groups: LF (40 F plus no Cr-Met supplementation in the $2^{nd}$ fattening period), LFCM (40LF plus added 400 ppb of Cr-Met during the $2^{nd}$ fattening period), HF (60 F plus no added Cr-Met during the $2^{nd}$ fattening period) and HFCM (60 F plus added 400 ppb of Cr-Met in the $2^{nd}$ fattening period). Dry matter intake of the treatment diets did not differ during the raising and $1^{th}$ fattening period (P > 0.05). The ADG in the raising period showed no difference between the 40 F and 60 F groups (P > 0.05). Carcass characteristics including rib-eye area and meat yield index were higher in HF than the other treatment groups (P < 0.05). The HF group tended to show a higher (P = 0.08) marbling score than the LF group whereas the HFCM group showed a higher marbling score than the LFCM group (P < 0.05). HDL was higher and LDL lower in groups fed with Cr-Met than in other groups whereas glucose showed the lowest value in HF group (P < 0.05). Triglyceride (TG), Cholesterol, PUN and total protein (TP) were the same among all treatment groups (P > 0.05). The Insulin concentration in the blood was significantly higher for the HFCM group than for the LF, LFCM and HF groups (P < 0.05). It is concluded that supplementation of chromium-methionine chelate could improve meat quality in beef steers.