PSXIV-12 Effect of the addition of canola oil on digestibility, rumen fermentation and methane emissions in beef cattle in the Mexican tropic

• Published in: Journal of animal science 2019-12, Vol.97 (Supplement_3), p.440-441
• Main Authors: Aviles-Nieto, Jonathan, Marquez-Mota, Claudia, Romero-Pérez, Atmir, Talamantes-Gómez, José, Castillo-Gallegos, Epigmenio, Jarillo, Jesus, Corona, Luis
• Format: Article
• Language: English
• Subjects: POSTER PRESENTATIONS
• ISSN: 0021-8812; 1525-3163
• DOI: 10.1093/jas/skz258.872

Abstract An experiment was performed to evaluate the effect of canola oil (CO) supplementation at 4 inclusion rates [CO0=0%, CO2=2%, CO4=4%, and CO6=6% of dry matter intake (DMI)] on digestibility, volatile fat acids (VFA), a mmonia nitrogen (NH3-N), protozoa and methane (CH4) emissions, in cows grazing a tropical grass (Brachiaria sp.). Four cows (Bos taurus × Bos indicus) with rumen cannula (658 ± 92 kg) were randomly assigned to a Latin Square design with 4 treatments and 4 periods (19-d each). Treatments were offered daily at 0600 h and 1500 h together with a commercial concentrate (1% of EBW). Fecal output was measured using an external marker (Cr2O3) dosed once per day for 9 days. Fecal output along with digestibility data were used to estimate DMI. Methane production was monitored twice a day, for 5 consecutive-days, using infrared gas analyzers (Guardian Plus) at the time of CO supplementation. Rumen contents were collected at 0300 h and every 4-h during the last 2-d of each period. Data of digestibility were analyzed as a Latin Square using a mixed model procedure (SAS Inst. Inc., Cary, NC). For ruminal fermentation parameters, collection time was considered a repeated measure. Orthogonal polynomials were performed to evaluate linear and quadratic effects. No effect was observed on fiber digestibility, or any nutrient evaluated with up to 6% CO inclusion. Total protozoa (x104cells/mL), methane emission and acetate molar proportion decreased (P < 0.01) while propionate increased (P < 0.01) with consequent reduction on the acetate:propionate ratio (CO0=3.2, CO2=2.8, CO4=2.6, CO6=2.4; P < 0.01) as the level of CO increased. In conclusion, supplementing CO to animals consuming a tropical forage-based diet, may represent a viable option to reduce CH4 emissions without having a negative effect on the digestibility of the NDF.