Effect of method of diet delivery to dairy cows on enteric methane emissions

Citation

135. Benchaar, C., and F. Hassanat. 2019. Effect of method of diet delivery to dairy cows on enteric methane emissions. J. Dairy Sci. Vol. 102 (Suppl. 1.): 375.

Résumé en langage clair

This study investigated the effects of method of diet delivery (con-centrates and forages separately versus total mixed ration) on enteric methane emissions, digestion, and milk production. In a crossover design (35-d periods), 16 lactating multiparous Holstein cows (BW = 647 ± 84 kg; DIM = 78 ± 39.3 d; milk yield = 46 ± 6.3 kg) were fed (ad libitum; 5% orts on as-fed basis) a diet as concentrates and forages separately (CF), or as a total mixed ration (TMR). The diet was composed of 47% pelleted concentrates and 53% Forages (alfalfa silage, corn silage and timothy hay). Production of CH4 was determined (5 consecutive days) using air flow-controlled chambers, while DMI, milk performance and DM apparent-total-tract digestibility were determined over 7 consecu-tive days. Data were analyzed using the MIXED procedure of SAS and significance was declared at P ≤ 0.05. Method of diet delivery had no effect on DMI (26 kg/d), or yields of milk (45.5 kg/d), milk fat (1.41 kg/d) and milk protein (1.46 kg/d). Apparent-total-tract digestibility of DM was higher when cows were fed CF (69.9%) compared with when fed TMR (68.9%). Enteric CH4 emission expressed as g/d, g/kg DMI and as percentage of gross energy intake averaged 420 g/d, 16.2 g/kg and 4.9%, respectively and was not affected by diet delivery method. Results of this study show that offering the diet as concentrates and forages separately or as total mixed ration did not influence enteric CH4emissions or milk performance of dairy cows.

Résumé

This study investigated the effects of method of diet delivery (con-centrates and forages separately versus total mixed ration) on enteric methane emissions, digestion, and milk production. In a crossover design (35-d periods), 16 lactating multiparous Holstein cows (BW = 647 ± 84 kg; DIM = 78 ± 39.3 d; milk yield = 46 ± 6.3 kg) were fed (ad libitum; 5% orts on as-fed basis) a diet as concentrates and forages separately (CF), or as a total mixed ration (TMR). The diet was composed of 47% pelleted concentrates and 53% Forages (alfalfa silage, corn silage and timothy hay). Production of CH4 was determined (5 consecutive days) using air flow-controlled chambers, while DMI, milk performance and DM apparent-total-tract digestibility were determined over 7 consecu-tive days. Data were analyzed using the MIXED procedure of SAS and significance was declared at P ≤ 0.05. Method of diet delivery had no effect on DMI (26 kg/d), or yields of milk (45.5 kg/d), milk fat (1.41 kg/d) and milk protein (1.46 kg/d). Apparent-total-tract digestibility of DM was higher when cows were fed CF (69.9%) compared with when fed TMR (68.9%). Enteric CH4 emission expressed as g/d, g/kg DMI and as percentage of gross energy intake averaged 420 g/d, 16.2 g/kg and 4.9%, respectively and was not affected by diet delivery method. Results of this study show that offering the diet as concentrates and forages separately or as total mixed ration did not influence enteric CH4emissions or milk performance of dairy cows.

Date de publication

2019-06-23

Profils d'auteurs