<p><b>Context.</b> Genotype by environment interaction or sire re-ranking between measurements of
methane emission in different environments or from using different measurement protocols can
affect the efficiency of selection strategies to abate methane emission. <b>Aim.</b> This study tested
the hypothesis that measurements of methane emission from grazing sheep under field
conditions, where the feed intake is unknown, are genetically correlated to measurements in a
controlled environment where feed intake is known. <b>Methods.</b> Data on emission of methane
and carbon dioxide and uptake of oxygen were measured using portable accumulation chambers
from 499 animals in a controlled environment in New South Wales and 1382 animals in a
grazing environment in Western Australia were analysed. Genetic linkage between both
environments was provided by 140 sires with progeny in both environments. Multi-variate
animal models were used to estimate genetic parameters for the three gas traits corrected for
liveweight. Genetic groups were fitted in the models to account for breed differences. Genetic
correlations between the field and controlled environments for the three traits were estimated
using bivariate models. <b>Key results.</b> Animals in the controlled environment had higher methane
emission compared to the animals in the field environment (37.0 ± s.d 9.3 and 35.3 ± s.d 9.4
for two protocols vs 12.9 ± s.d 5.1 and 14.6 ± s.d 4.8 mL/min for lambs and ewes (±s.d);
P < 0.05) but carbon dioxide emission and oxygen uptake did not significantly differ. The
heritability estimates for methane emission, carbon dioxide emission and oxygen uptake were
0.15, 0.06 and 0.11 for the controlled environment and 0.17, 0.27 and 0.35 for the field
environment. The repeatability for the traits in the controlled environment ranged from 0.51 to
0.59 and from 0.24 to 0.38 in the field environment. Genetic correlations were high (0.85–0.99)
but with high standard errors. <b>Conclusion.</b> Methane emission phenotypes measured
using portable accumulation chambers in grazing sheep can be used in genetic evaluation to
estimate breeding values for genetic improvement of emission related traits. The combined
measurement protocol-environment did not lead to re-ranking of sires. <b>Implication.</b> These
results suggest that both phenotypes could be used in selection for reduced methane emission
in grazing sheep. However, this needs to be consolidated using a larger number of animals and
sires with larger progeny groups in different environments.</p>