Producción CyT

Guidelines for use of sulphur hexafluoride (SF 6) tracer technique to measure enteric methane emissions from ruminants.

Libro

Autoría:

Berndt A. ; Boland T. ; Deighton M. ; GERE, JOSE IGNACIO ; Grainger C. ; Hegarty R. ; Iwaasa A. ; Koolaard J. P. ; Lassey K. ; Luo D. ; Martin R. ; Martin C. ; Moate P. ; Molano G. ; Pinares-Patiño C. ; Ribaux R. ; Swainson N. ; Waghorn G. ; Williams S.

Fecha:

2014

Editorial y Lugar de Edición:

Ministry for Primary Industries

ISBN:

978-0-478-43210-7

Resumen *

The SF6 tracer technique relies on a known source of a synthetic inert tracer ? sulphur hexafluoride (SF6) inserted in the rumen, where at least 90% of CH4 is sourced. Breath, characterised as respired plus eructed gases, is sampled and analysed (Chapter 2). This technique can be used with untethered, freely-grazing animals. Moreover, the equipment cost per anim al under test is much lower than for chamberexperiments, enabling dozens or even hundreds of animals to be breath-tested in a single experiment (e.g. (McNaughton et al., 2005). Several experimenters have compared enclosure and SF6 tracer techniques ((Boadi et al., 2002, Grainger et al., 2007, McGinn et al., 2006, Muñoz et al., 2012, Pinares-Patiño et al., 2008, Pinares-Patiño et al., 2011), and those comparisons are generally favourable. However, emission estimates by the SF6 tracer technique appear subject to greater variability than those from enclosure techniques. On the one hand this may suggest that the SF6 tracer technique superimposes its own inherent variability on natural biological variability, or that the technique is not always applied with sufficient attention to detail. On the other hand, the SF6 tracer technique may be capturing real variability of animal intake and behaviour that is masked in chambers, where intake and behaviour is more controlled. The SF6 tracer technique enjoys wide acceptance, but with a variety of implementations. This variety arises from different equipment and hardware designs, and variations in innovative hardware developments, as well as differences in experimental protocols and data analysis. These guidelines are the culmination of a project to bring experienced SF6 practitioners together, and to pool those experiences into a composite guide. The first stage of that project was a workshop ? held in Palmerston North, New Zealand, in March 2011 and chaired by Keith Lassey, then of NIWA ? featuring international practitioners skilled in a range of SF6 applications. An outline of these guidelines and an allocation of authorships are outputs from that workshop. Información suministrada por el agente en SIGEVA

Palabras Clave

GUIDELINESTRACER TECHNIQUEMETHANE EMISSION