Premium
Evaluation of the single pulse dose method for estimating herbage intake by cattle in a large scale free‐ranging system
Author(s) -
Nakano Miwa,
Yayota Masato,
Ohtani Shigeru
Publication year - 2008
Publication title -
grassland science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.388
H-Index - 19
eISSN - 1744-697X
pISSN - 1744-6961
DOI - 10.1111/j.1744-697x.2008.00107.x
Subject(s) - grazing , feces , zoology , chromic oxide , pasture , pulse (music) , mathematics , biology , agronomy , ecology , physics , optics , detector
The single pulse dose method may be one of the few practical techniques for estimating fecal output and herbage intake in animals in large scale free‐ranging systems because the method reduces labor and time involved in capturing animals and collecting feces. This study aimed to evaluate the single pulse dose method using rare earth marker‐labeled herbage for estimating fecal output and herbage intake by cattle, in comparison with the actual values and the continuous dose method using chromium oxide. In experiment 1, the fecal output and herbage intake estimated by the single pulse dose method (FO S and HI S ) and by the continuous dose method (FO C and HI C ) were compared with the actual values in the zero grazing condition. Six Japanese Black cows were kept in individual pens and fed fresh herbage ad libitum . Average FO S and HI S were 104% and 108% of the actual values, respectively, and were closer to the actual values than FO C and HI C (85% and 89%). However, the animal‐to‐animal variation represented by the standard deviation in the single pulse dose method was greater than that in the continuous dose method. In experiment 2, the single pulse dose and the continuous dose methods were compared in the grazing condition, using six Japanese Black cows grazing a 77‐ha pasture. Although the differences of the mean fecal output and herbage intake between the two methods were greater than those in the zero grazing condition, the same tendency as that under the zero grazing condition was observed. The results suggest that the single pulse dose method slightly overestimates the herbage intake compared with the actual value and produces slightly less stable estimates than the continuous dose method. However, the method can be useful for estimating herbage intake by animals in large scale free‐ranging systems where the use of other estimation methods is difficult.