Fecha/hora: 12/06/2024 09:18:38

Biblioteca(s): | INIA Treinta y Tres.
Fecha corriente: | 24/11/2015
Fecha de la última actualización: | 19/09/2018
Autoria: | VELAZCO, J.I.; MAYER, D.G.; ZIMMERMAN, S.; HEGARTY, S.
Afiliación: | JOSÉ IGNACIO VELAZCO DE LOS REYES, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay.
Título: | Use of short-term breath measures to estimate daily methane production by cattle.
Año de publicación: | 2015
Fuente/Imprenta: | Animal, 2015, v. 10 (1) p. 25-33.
ISBN: | 10.1017/s1751731115001603
Idioma: | Inglés
Notas: | Article history: Received 30 September 2014; Accepted 29 June 2015.

Contenido:

Methods to measure enteric methane (CH4) emissions from individual ruminants in their production environment are required to validate emission inventories and verify mitigation claims. Estimates of daily methane production (DMP) based on consolidated short-term emission measurements are developing, but method verification is required. Two cattle experiments were undertaken to test the hypothesis that DMP estimated by averaging multiple short-term breath measures of methane emission rate did not differ from DMP measured in respiration chambers (RC). Short-term emission rates were obtained from a GreenFeed Emissions Monitoring (GEM) unit, which measured emission rate while cattle consumed a dispensed supplement. In experiment 1 (Expt. 1), four non-lactating cattle (LW = 518 kg) were adapted for 18 days then measured for six consecutive periods. Each period consisted of 2 days of ad libitum intake and GEM emission measurement followed by 1 day in the RC. A prototype GEM unit releasing water as an attractant (GEM water) was also evaluated in Expt. 1. Experiment 2 (Expt. 2) was a larger study based on similar design with 10 cattle (LW = 365 kg), adapted for 21 days and GEM measurement was extended to 3 days in each of the six periods. In Expt. 1, there was no difference in DMP estimated by the GEM unit relative to the RC (209.7 v. 215.1 g CH4/day) and no difference between these methods in methane yield (MY, 22.7 v. 23.7 g CH4/kg of dry matter intake, DMI). In Expt. 2, the correlation between GEM and RC measures of DMP and MY were assessed using 95% confidence intervals, with no difference in DMP or MY between
methods and high correlations between GEM and RC measures for DMP ( r = 0.85; 215 v. 198 g CH4/day SEM = 3.0) and for MY ( r = 0.60; 23.8 v. 22.1 g CH4/kg DMI SEM = 0.42). When data from both experiments was combined neither DMP nor MY differed between GEM- and RC-based measures ( P >0.05). GEM water-based estimates of DMP and MY were lower than RC and GEM ( P <0.05). Cattle accessed the GEM water unit with similar frequency to the GEM unit (2.8 v. 3.5 times/day, respectively) but eructation frequency was reduced from 1.31 times/min (GEM) to once every 2.6 min (GEM water). These studies confirm the hypothesis that DMP estimated by averaging multiple short-term breath measures of methane emission rate using GEM does not differ from measures of DMP obtained from RCs. Further, combining many short-term measures of methane production rate during supplement consumption provides an estimate of DMP, which can be usefully applied in estimating MY.

Palabras-Clave: | CATTLE; GAS METANO; GREENHOUSE GASES; MEASUREMENT; METHANE.
Thesagro: | GANADO; GASES DE EFECTO INVERNADERO; MEDIDAS.
Categoría del tema: | T01 Polución
Registro original: | INIA Treinta y Tres (TT)
Ejemplares: | TT - (101079-1) - PXI - AP - DD - PP/ANIMAL/2015/VELAZCO/2 -  -  - DIS