The Survey of Particle Size of Total Mixed Ration in Korea

국내 TMR의 입자도에 관한 조사 연구

  • Ki, K.S. (National Livestock Research Institute) ;
  • Kim, H.S. (National Livestock Research Institute) ;
  • Jeong, H.Y. (National Livestock Research Institute) ;
  • Lee, H.J. (National Livestock Research Institute) ;
  • Ahn, B.S. (National Livestock Research Institute) ;
  • Kim, J.S. (National Livestock Research Institute) ;
  • Kwang, S.W. (National Livestock Research Institute) ;
  • Kim, Y.K. (Chungnam National University) ;
  • Ha, J.K. (Seoul National University)
  • Published : 2003.10.31


This study was carried out to survey operation system of self-making TMR and particle size of self-making and commercial TMR, then to compare TMR particle size recommended by Penn State Particle Size Separator. Daily mixing time in self-making TMR averaged 48.6${\pm}$28.0min., 2 augar type of mixer was most by 55.5% and daily 2 times of mixing in summer and other season was 44.4 and 22.2%, respectively. Percentage of residual feed in upper sieve(19mm diameter), middle sieve(8 to 18mm diameter) and lower pen was 21.5~25.6%, 16.0~25.8%, 52.8~61.4%, respectively, at self-making TMR mixer. Percentage of particle sizes of more than 19mm in self-making and commercial TMR was 24.9${\pm}$1.4 and 26.2${\pm}$1.7%, that of 8-10mm 22.8${\pm}$1.0 and 12.8${\pm}$1.2 and that of less than 8mm 52.3${\pm}$1.7 and 61.0${\pm}$1.5, respectively, which in particle length of 8~13mm in self-making and commercial TMR was lower by 82.6 and 100% compared to that recommended by Penn State particle separator, respectively. Especially there was not particle length of more than 19mm in commercial TMR at all. It is necessary to check the number of cows ruminating in a farm in order to estimate the particle size of TMR; it is recommended to change the TMR mixing time or the TMR formulae if the proportion of ruminating cows in a farm is less than 40 %.


TMR;Particle size;Survey;Mixer;Mixing time


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