Abstract
The objective of this review was to examine the application and relative efficiency of the proprietary hand-held Laser Methane
Detector (LMD) in livestock production, with a focus on opportunities and challenges in different production systems. The LMD is
based on IR absorption spectroscopy, uses a semiconductor laser as a collimated excitation source and uses the second harmonic
detection of wavelength modulation spectroscopy to establish a methane (CH4) concentration measurement. The use of the LMD
for CH4 detection in dairy cows is relatively recent. Although developed for entirely different purposes, the LMD provides an
opportunity for non-invasive and non-contact scan sampling of enteric CH4. With the possibility for real-time CH4 measurements,
the LMD offers a molecular-sensitive technique for enteric CH4 detection in ruminants. Initial studies have demonstrated a
relatively strong agreement between CH4 measurements from the LMD with those recorded in the indirect open-circuit respiration
calorimetric chamber (correlation coefficient, r50.8, P,0.001). The LMD has also demonstrated a strong ability to detect
periods of high-enteric CH4 concentration (sensitivity595%) and the ability to avoid misclassifying periods of low-enteric CH4
concentration (specificity579%). Being portable, the LMD enables spot sampling of methane in different locations and
production systems. Two challenges are discussed in the present review. First is on extracting a representation of a point
measurement from breath cycle concentrations. The other is on using the LMD in grazing environment. Work so far has shown
the need to integrate ambient condition statistics in the flux values. Despite the challenges that have been associated with the
use of the LMD, with further validation, the technique has the potential to be utilised as an alternative method in enteric CH4
measurements in ruminants.
Original language | English |
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Pages (from-to) | 394 - 400 |
Number of pages | 7 |
Journal | Animal |
Volume | 7 |
Issue number | s2 |
DOIs | |
Publication status | Print publication - Jun 2013 |
Bibliographical note
1023323Keywords
- Laser systems
- Methane
- Ruminants